Emergency Department Triage (2024)

December 1, 2024December 1, 2024 ~ iEM Education Project Team ~ Leave a comment

by Priya Arumuganathan and Scott Findley

Introduction

Triage is the process of sorting patients by severity of illness to ensure care is administered in a timely fashion according to each patient’s need. When specifically applied to the emergency department, “Emergency Department (ED) Triage” is used to quickly assess, risk-stratify, and manage incoming patients before their complete evaluation. A triage process allows systems to safely operate an influx of multiple patients with varying acuity levels in situations when clinical demand exceeds capacity. Formal triage systems have been employed since as early as the 19th century in warfare settings to effectively handle the growing amounts of field casualties [1].

Today, emergency triage can be generally separated into three distinct phases: prehospital triage, triage at the scene, and emergency department triage. Many different types of triage systems have been developed and implemented worldwide [2]. In this section, we will focus on emergency department triage and some of the most well-known triage systems globally.

Performing a Rapid Triage Assessment

The “rapid triage assessment” is essential to any triage system. Those performing the rapid triage assessment should have some clinical experience and a keen eye to quickly identify patients who need to be seen urgently. The goal of triage is to determine which patients need immediate attention, which patients can wait to be seen, and to manage large patient volumes safely. To accomplish this, one must gather pertinent history and physical exam findings quickly and efficiently.

Performing a Focused History

Obtaining a quick and focused history is of utmost importance during the rapid triage assessment. To summarize, providers must be able to get symptoms pertinent to the patient’s presentation, any relevant events leading to their presentation, and pertinent past medical history and allergies. One mnemonic that is useful and used by many for history-gathering is SAMPLE (as below) [3]:

The SAMPLE mnemonic is a structured method for gathering key clinical information during an emergency assessment. It serves as a framework for emergency medical personnel to obtain essential details quickly and efficiently, allowing them to prioritize care and decide on the best course of action. Each component of the mnemonic corresponds to a specific area of focus in history-gathering, which is vital for rapid triage in the emergency department or pre-hospital setting. Below is a more detailed breakdown of each element:

S – Signs & Symptoms
The first and most immediate part of the assessment focuses on the patient’s presenting signs and symptoms. These may include both subjective (what the patient describes) and objective (what the healthcare provider observes) data. For example, a patient may report chest pain, difficulty breathing, or nausea, while a provider might note abnormal vital signs or physical findings. It’s crucial to obtain a clear description of the symptoms, including onset, duration, intensity, and any factors that may have worsened or alleviated them. Understanding the signs and symptoms will help determine the severity of the condition and direct the urgency of intervention.

A – Allergies
Gathering information about any known allergies is vital in guiding treatment decisions, especially in emergencies where medications or interventions are required quickly. For example, if a patient has a known allergy to penicillin, it is essential to avoid using antibiotics in that class. Allergies to food, medications, environmental triggers, and latex should all be considered. In addition, healthcare providers should be mindful of potential allergic reactions that could complicate the management of the patient’s condition.

M – Medications
A comprehensive medication history helps identify substances that may impact the patient’s current clinical situation. This includes prescribed medications, over-the-counter drugs, supplements, and any recent changes to a medication regimen. For example, a patient taking blood thinners such as warfarin may require careful monitoring for signs of bleeding, while those on insulin may need their blood sugar levels closely monitored. Knowledge of recent changes, doses, and the possibility of drug interactions is crucial in the emergency setting.

P – Past Pertinent History
Past medical history (PMH) can provide essential context for understanding the patient’s current presentation. This includes chronic conditions such as diabetes, hypertension, or asthma, as well as previous hospitalizations, surgeries, or significant illnesses. Understanding a patient’s medical history helps healthcare providers anticipate complications and tailor their approach. For instance, if a patient with a history of seizures presents with altered mental status, healthcare providers will prioritize ruling out or treating seizure activity or postictal states.

L – Last Oral Intake
Knowing the last oral intake—what the patient has eaten or drunk—can provide valuable information about the patient’s condition, especially in cases of poisoning, drug overdoses, or gastrointestinal distress. For example, the timing of food or drink ingestion could suggest an issue with digestion or absorption, which may influence the choice of interventions. In cases of poisoning, knowing whether the patient ingested a toxic substance recently can impact the decision to administer activated charcoal or other antidotes. Additionally, the last oral intake can be crucial if the patient is scheduled for surgery or other procedures, as it helps assess the risk of aspiration or anesthesia complications.

E – Events Leading to the Incident
Understanding the sequence of events that led to the current emergency is essential for diagnosing the cause and assessing the patient’s clinical needs. For example, was the patient involved in a motor vehicle accident, or did they experience a sudden onset of chest pain while exercising? Gathering this information helps to identify the mechanism of injury or the type of acute event, which could significantly alter the emergency management plan. It also provides insight into potential causes of the symptoms and any necessary preventive or therapeutic actions.

Purpose and Application of the SAMPLE Mnemonic in Rapid Triage

The SAMPLE mnemonic is a concise tool designed to quickly gather relevant historical information that can significantly impact clinical decision-making in the emergency department. This structured approach is particularly helpful in high-pressure environments where time is critical, such as during triage or when managing patients with complex or time-sensitive conditions.

The goal during history-gathering in an emergency is to obtain just enough, but not too much detail. Too much detail may delay treatment, while too little may result in missing critical information. For example, a lengthy review of a patient’s family history may be less pertinent in an acute situation compared to knowing their current medication list or the events leading to the emergency. The SAMPLE framework ensures that the provider gathers relevant information to make informed decisions about the next steps in care, whether that be immediate intervention, further diagnostics, or a more detailed secondary assessment.

The SAMPLE mnemonic is an effective tool for emergency practitioners to rapidly gather crucial information during triage and initial assessment. By focusing on the most important elements—signs and symptoms, allergies, medications, past medical history, last oral intake, and events leading up to the incident—providers can prioritize interventions, anticipate potential complications, and provide optimal care in emergency settings.

Performing a Focused Physical Exam

After performing a focused history, it is important to use the information gathered to guide your focused physical exam. For example, a patient presenting with the chief complaint of sore throat should receive an expedited examination of the head, ears, mouth, and neck. The rest of the physical exam should be deferred unless the patient has another complaint that is not covered by these sections. The purpose of the focused physical exam is to look for “red flag” exam findings that would warrant more immediate attention and intervention, such as the peritonitic abdomen in the patient presenting with abdominal pain, oropharyngeal swelling in the patient presenting with shortness of breath and rash, left-sided flaccidity in the patient presenting with sudden onset weakness and tingling, and other concerning findings [4].

Vital Signs and Objective Data

There are clues to key providers about how sick their patients are. One of the most important clues is a patient’s set of vitals; therefore, it is exceedingly important to obtain a full set of vitals for all patients arriving at the emergency department. Vitals at either extreme of the spectrum are equally important, and grossly abnormal vitals should prompt a more expedited triage and shorter waiting times. Other clues that help identify sick patients include the level of pain, duration of symptoms, level of consciousness, and mechanism of injury. Suppose someone is determined to be in distress at any point during the triage process. In that case, they must be brought to a designated patient care area for immediate ED provider attention. In the paragraphs below, we will discuss this further regarding adult populations.

Heart Rate

Bradycardia is a heart rate of less than 60 bpm, while tachycardia is a heart rate of more than 100 bpm [5]. If a patient is experiencing associated hypotension with an abnormal heart rate, then it is obvious that they are sick. However, there are other key questions that you may ask in the physical exam to elucidate further a patient’s severity of illness regarding an abnormal heart rate. For example, experiencing associated chest pain, palpitations, extreme fatigue or weakness, altered mental status, shortness of breath, or nausea can be signs that the abnormal heart rate is due to a concerning underlying pathology in the patient. Tachycardia can be indicative of infection, dysrhythmia, acute blood loss, and toxin exposure amongst other etiologies. It is also important to ask about medication use in these patients as this can be your first sign of an accidental (or intentional) chronotropic medication overdose – such as with beta-blockers, calcium channel blockers, and other medications that need to be seen by a medical provider quickly.

Blood Pressure

Hypotension is defined as a blood pressure less than 90/60 mmHg, while hypertension is defined as more than 140/90 mmHg [5]. With hypotension, it is important to first quickly assess if a patient is experiencing a decreased mental status and level of alertness in order to determine if any immediate interventions are needed – if so, this patient is definitely sick and cannot wait for care. Next, it is important to assess for possible causes of hypotension and severe illness, such as septic, hemorrhagic, neurogenic, and anaphylactic shock. For hypertension, it is important to assess for signs that could indicate end-organ failure, such as chest pain, shortness of breath, and focal neurologic deficits. Patients exhibiting the above symptoms should be evaluated sooner rather than later.

Respiratory Rate

Tachypnea is defined as a respiratory rate above 20 bpm, while bradypnea is defined as a respiratory rate below 12 bpm [5]. Apnea is the total absence of breathing. Bradypnea and apnea can be seen in many conditions, including traumatic brain injury and heroin overdose. Tachypnea is seen in many conditions, including asthma exacerbation and conditions causing metabolic derangement, such as diabetic ketoacidosis. If a patient is not breathing or experiencing decreased oxygen saturation along with abnormal respirations, then it is obvious they are sick. However, for those cases that are less obvious, it is important to observe the patient’s work of breathing with their respirations. Those who appear to have a significantly increased respiratory effort, are becoming tired, or are experiencing shallow respirations will need medical evaluation and care sooner rather than later. Their fatiguing respiratory effort will eventually lead to respiratory failure and hypoxia. Those with stories concerning an underlying process that could quickly compromise respiratory function should also be prioritized. For example, a patient who presents with a story suspicious of intracranial hemorrhage who appears sleepy and only moans in response to questions is at high risk for respiratory decompensation.

Oxygen Saturation

Hypoxia is defined as an oxygen saturation below 92% [5]. While different patients can tolerate various oxygen saturation levels depending on their smoking status, history of lung disease, and other past medical history, it is important to assess the work of breathing and level of alertness in patients with low readings. Patients who appear to have increased work of breathing, decreased respirations, or decreased level of alertness are at risk for respiratory decompensation. These patients should be evaluated and treated sooner rather than later.

Temperature

Hypothermia is defined as a temperature below 35 C. In contrast, hyperthermia is defined as a temperature above 38 C [5]. Hypothermic patients must be rewarmed depending on the degree of hypothermia (this will be discussed in later chapters). It is important to determine the reason for their hypothermia – such as sepsis, submersion injury, and prolonged cold exposure. There are many reasons for hyperthermia, including but not limited to infection, prolonged heat exposure, and certain types of medication overdose. The hyperthermic patient must be physically cooled and given antipyretics or other medications depending on the cause of their hyperthermia. These are all causes for concern and immediate interventions.

Pain

The severity and location of pain can also help identify patients who need prompt attention. Patients in severe pain will need immediate attention and medications to alleviate their pain. The location of pain can also be a clue to a patient’s severity of illness. For example, chest pain radiating to the back could represent an aortic dissection, right lower quadrant abdominal pain could represent appendicitis, and headache with neck stiffness could represent bacterial meningitis. Patients with concerning pain severity and location should be prioritized [6].

Duration and Mechanism

The duration of symptoms can also be a clue to a patient’s severity of illness. In general, acute complaints, or complaints that occur with a sudden or recent onset, should raise higher suspicion for serious etiologies than a chronic complaint that has been occurring without change for weeks to months [6]. A patient’s mechanism of injury is also important to consider; for example, a person who has fallen from a significant height or has been involved in a high-speed accident should be evaluated quickly as well.

Level of Consciousness

Level of consciousness exists on a spectrum, from those who are unresponsive to those who are completely awake and alert. Unresponsive patients should receive immediate attention and interventions, including chest compressions if they are without a pulse and intubation. Lethargic patients and those experiencing quickly decreasing levels of alertness should also be prioritized. Those sleepy or confused should be seen urgently, while those fully awake and alert may wait to be seen if they are without other concerning signs/symptoms [6].

Triage is a complex process involving several components, and it can be challenging. Triage providers play a crucial role in ensuring the efficiency and safety of the ED. They must quickly and accurately assess a patient’s severity of illness to determine how long different patients can safely wait for care. It is essential that they do not focus on diagnosing the patient’s condition during triage, as this can delay the process. Such delays can compromise care for all patients, allowing seriously ill individuals to go unnoticed for extended periods while their condition worsens. Remember that a comprehensive history, examination, diagnostic work-up, and treatment will occur once the patient is admitted to a care area.

Triage Systems

Triage is a complex process that needs to be done expediently, especially when facing large patient volumes. Fortunately, many triage systems have been developed to help guide providers in quickly and accurately risk-stratifying patients during the rapid triage assessment. We will discuss some of the most popular and widely used triage systems, such as the Manchester Triage System and the Emergency Severity Index.

Manchester Triage System

One of the most well-known and globally used triage systems is the Manchester Triage System (MTS). It was developed in the UK and is widely used worldwide. This triage system helps ensure patient safety by defining the maximum time each patient can wait before being seen and treated. The MTS contains flowcharts for various presenting complaints that help to distinguish the severity of illness based on key “discriminators” (signs and symptoms) [7]. Each level of severity is assigned a different color. Red indicates immediate evaluation, while blue indicates non-urgent evaluation (can wait up to 240 minutes). Flowcharts are available for various chief complaints in adult and pediatric patients. The MTS (Figure) for the adult chief complaint of “chest pain” is discussed below [8].

RED: Immediate/Life-Threatening

The red category signifies the highest level of urgency, where the situation is life-threatening and requires immediate medical intervention. The maximum waiting time is 0 minutes, indicating that the patient must receive attention without delay. Correlating examples for chest pain in this category include airway compromise, inadequate breathing, or shock. These conditions are critical as they can lead to rapid deterioration or death if not addressed promptly. Immediate treatment might involve airway management, advanced resuscitation, or stabilization of vital signs.

ORANGE: Emergent/Could Become Life-Threatening

The orange category represents conditions that are not immediately life-threatening but could escalate to critical levels if left untreated. The maximum waiting time in this category is 10 minutes, emphasizing the need for swift medical evaluation and intervention. Examples of chest pain scenarios in this category include severe pain, cardiac pain, acute shortness of breath, or abnormal pulse. These symptoms often indicate serious underlying issues such as myocardial infarction, severe arrhythmias, or pulmonary embolism, all of which require urgent diagnostic and therapeutic measures to prevent deterioration.

YELLOW: Urgent/Not Life-Threatening

In the yellow category, conditions are urgent but not immediately life-threatening. The maximum waiting time is 60 minutes, providing a moderate window for assessment and treatment. Correlating examples for chest pain include pleuritic pain, persistent vomiting, history of cardiac disease, or moderate pain. These symptoms may point to less severe causes, such as musculoskeletal issues, gastroesophageal reflux, or pleurisy. However, the history of cardiac disease suggests a need for careful evaluation to rule out more serious conditions.

GREEN: Semi-Urgent/Not Life-Threatening

The green category involves semi-urgent conditions where the likelihood of life-threatening complications is low. Patients in this category can wait up to 120 minutes for treatment. Examples include vomiting, mild pain, or recent problems. Chest pain in this category is typically associated with benign causes, such as anxiety, mild gastrointestinal issues, or a musculoskeletal strain. While these cases are not critical, timely assessment ensures patient comfort and prevents unnecessary progression of symptoms.

BLUE: Non-Urgent/Needs Treatment When Time Permits

The blue category is for non-urgent conditions that require treatment only when time permits. The maximum waiting time is 240 minutes, as these cases are unlikely to escalate to a critical level. Examples include other complaints that may not even directly relate to chest pain or are minor in nature. These could involve mild discomfort or non-specific symptoms that do not pose any immediate threat to the patient’s health. Such cases can be safely managed without priority over more urgent categories.

Emergency Severity Index

Much like the Manchester Triage System, the Emergency Severity Index triage system (developed in the USA) is also globally known and used. It stratifies patients into five levels: level 1, the most urgent, and level 5, the least urgent. It also helps to determine what resources are necessary to move a patient toward disposition. It is based on four key decision points: does the patient require life-saving interventions (Step A), are they in a high-risk situation (Step B), how many resources do they need (Step C), and what are their vitals (Step D)? The ESI Triage Algorithm, types of resources, and level of urgency, along with examples, are discussed below [9].

Step-by-Step ESI Triage Algorithm

Step A: The first question asks whether the patient requires immediate, life-saving interventions. If the answer is “Yes,” the patient is classified as Level 1, indicating the highest level of urgency. If “No,” the triage proceeds to Step B.
Step B: This step evaluates whether the patient is in a high-risk situation, is lethargic, confused, or in severe pain. A “Yes” response classifies the patient as Level 2, while a “No” response advances the process to Step C.
Step C: At this stage, the need for medical resources is assessed. If the patient requires only one resource, they are categorized as Level 4. If multiple resources are needed, they may qualify for a higher urgency level, prompting a review in Step D.
Step D: This step determines whether the patient exhibits “danger zone” vital signs, such as abnormal heart rate, respiratory rate, or oxygen saturation. A “Yes” response results in a Level 2 classification, while “No” leads to a Level 3 classification.

Types of Resources Defined by ESI

Resources play a critical role in the ESI system, as they help determine patient levels during Step C. Common resource types include:

Diagnostic Tools: Labs, EKG/ECG, X-rays, CT scans, MRI, or ultrasounds.
Treatment: IV fluids, IV/IM/nebulized medications, and specialist consultations.
Procedures: Simple procedures, such as laceration repair or Foley catheter insertion, are counted as one resource. Complex procedures, including conscious sedation, fracture reduction, and intubation, may require additional considerations.

Points according to required resources;

1 point for Labs (e.g., blood tests), EKG/ECG or X-rays, or Advanced Imaging (e.g., CT, MRI, or ultrasound).
1 point for IV fluids.
1 point for IV, IM, or nebulized medications.
1 point for a Specialist consultation.
1 point for a Simple procedure, such as laceration repair or Foley catheter placement.
2 points for a Complex procedure, such as conscious sedation, fracture reduction, or intubation.

These resource definitions allow triage staff to assess patient needs objectively. A higher number of resources often correlates with a more urgent ESI level.

ESI Levels and Their Corresponding Urgency

The ESI system categorizes patients into five levels of urgency based on their condition and resource needs:

Level 1 (Immediate): Patients need immediate attention due to life-threatening conditions like cardiac arrest.
Level 2 (Emergent): These patients are at high risk of rapid deterioration, such as those experiencing an asthma attack.
Level 3 (Urgent, Multiple Resources): Patients with conditions requiring multiple resources, like abdominal pain, fall into this category.
Level 4 (Stable, One Resource): These patients need only one resource, such as laceration repair.
Level 5 (Stable, No Resources): Patients with stable conditions requiring no resources, such as a prescription refill, are classified here.

Advanced Triage

Once you are comfortable with the above basic triage concepts, you can familiarize yourself with advanced triage considerations, such as ordering an initial diagnostic work-up and treatments.

Ordering an Initial Diagnostic Work-Up and Other Orders

As soon as a patient is determined to be sick or unstable, your priority should be to place them in a patient care area as quickly as possible for medical attention. You can then place initial orders, which should be directed toward stabilizing them. Placing IVs early and facilitating early medication/fluid administration can be life-saving measures. Be sure to ask these patients (or their loved ones) early in their evaluation regarding their wishes for cardiopulmonary resuscitation (CPR) and intubation. Once a patient is stable, or if they’re already stable, you can use their pertinent history and physical exam findings to guide your initial diagnostic imaging and labs. Consider your most likely diagnoses and “can’t miss diagnoses” when placing these initial orders [10].

Author

Priya Arumuganathan

Priya Arumuganathan, MD is a third year Emergency Medicine resident at West Virginia University. After residency, she will be completing a Global Emergency Medicine Fellowship at the University of Pennsylvania. During residency, Priya served as a Chief Resident and was very active in teaching core EM content, ultrasound skills, and procedural basics to medical students and new residents. Her rural background and training at several critical access hospitals have helped her build a foundation for working in low-resource environments, and she has been able to translate these skills to her global work. Her academic interests include EM education & training in low-resource environments, telemedicine, and rural health.

Scott Walker Findley

Dr. Findley is an associate professor with the WVU Department of Emergency Medicine. He splits time between the larger WVU academic centers and outlying rural emergency departments, spending most of his clinical time in single coverage facilities. After recognizing the challenges inherent in rural emergency medicine (EM), he designed and developed the WVU Division of Rural EM. Dr. Findley secured a federal telemedicine grant to expand telemedicine services in WV critical access hospitals, an institutional HOPE grant to assess per-birth needs in rural emergency departments, assisted with a rural specific response to COVID – 19, secured a position as medical director and advisor for Adventure WV, successfully launched a multisite rural EM rotation for residents, facilitated rural rotations for medical students, and oversaw the integration of rural EM lectures and simulated cases into the resident curriculum. In addition to remaining academically connected, Dr. Findley works closely with the WVU Emergency Department Divisions of ultrasound, EMS and Education to bring resources into the community sites and rural areas. Dr. Findley also sits on the national American College of Emergency Physicians (ACEP) Rural Emergency Medicine’s Task Force. He has taken an active role in research with local and national presentations as well as publishing in academic journals. Although these opportunities have been rewarding, Dr. Findley believes nothing teaches you more, maintains drive and sharpens focus better than pulling shifts and seeing patients and he plans to continue working the majority of his clinical hours in smaller departments.

Listen to the chapter

References

Robertson-Steel I. Evolution of triage systems. Emerg Med J. 2006;23(2):154-155. doi:10.1136/emj.2005.030270
Yancey CC, O’Rourke MC. Emergency Department Triage. In: StatPearls. Treasure Island (FL): StatPearls Publishing; August 31, 2022.
West Virginia Office of Emergency Medical Services. (2016, January 1). Assessment Mnemonics. Appendix D. Retrieved April 23, 2023, from https://www.wvoems.org/files/protocols/appendix/appendix-d-assessment-mnemonics
Society for Academic Emergency Medicine. (2008). Performing a complaint-directed history and Physical Examination. Clerkship Directors in Emergency Medicine. Retrieved April 23, 2023, from https://www.saem.org/about-saem/academies-interest-groups-affiliates2/cdem/for-students/online-education/m3-curriculum/group-focused-chief-complaint-history-physical-examination-and-differential-diagnosis/performing-a-complaint-directed-history-and-physical-examination
Balakumaran, J. (2020, June 30). Interpreting critical vital signs. Medical Concepts. Retrieved April 23, 2023, from https://canadiem.org/interpreting-critical-vital-signs/
Mackway-Jones, K., Marsden, J., & Windle, J. (2014). The Triage Method. In Emergency Triage (2nd ed., pp. 10–21). John Wiley & Sons.
Cicolo, E. A., Ayache Nishi, F., Ciqueto Peres, H. H., & Cruz, D. A. (2017). Effectiveness of the Manchester Triage System on time to treatment in the emergency department: a systematic review protocol. JBI database of systematic reviews and implementation reports, 15(4), 889–898. https://doi.org/10.11124/JBISRIR-2016-003119
Ganley, L., & Gloster, A. S. (2011). An overview of triage in the emergency department. Nursing standard (Royal College of Nursing (Great Britain) : 1987, 26(12), 49–58. https://doi.org/10.7748/ns2011.11.26.12.49.c8829
Gilboy N, Tanabe T, Travers D, Rosenau AM. (2011). Emergency Severity Index (ESI): A Triage Tool for Emergency Department Care, Version 4. Implementation Handbook 2012 Edition. AHRQ Publication No. 12-0014. Rockville, MD. Agency for Healthcare Research and Quality.
International Emergency Medicine Education Project. (2019, March 4). Core Senior EM Clerkship Topics. Emergency Medicine Clerkship – Approach to Chief Complaints. Retrieved April 23, 2023, from https://iem-student.org/em-clerkship-topics/

Reviewed and Edited By

Arif Alper Cevik, MD, FEMAT, FIFEM

Prof Cevik is an Emergency Medicine academician at United Arab Emirates University, interested in international emergency medicine, emergency medicine education, medical education, point of care ultrasound and trauma. He is the founder and director of the International Emergency Medicine Education Project – iem-student.org, chair of the International Federation for Emergency Medicine (IFEM) core curriculum and education committee and board member of the Asian Society for Emergency Medicine and Emirati Board of Emergency Medicine.

Clinical Decision Rules (2024)

November 24, 2024November 24, 2024 ~ iEM Education Project Team ~ Leave a comment

by Stacey Chamberlain

Definitions and Overview

Clinical Decision Rules (CDRs), also known as Decision “Instruments” or “Aids,” are evidence-based tools to assist the practitioner in decision-making for common complaints. In the Emergency Department (ED) setting, these decision aids are often used to help identify patients who might be at higher risk for serious conditions such as pulmonary embolism (PE) or intracranial hemorrhage (ICH), or they are used to prevent overuse of unnecessary testing, which is how many of the orthopedic rules are applied.

CDRs, despite being called “Rules,” are not meant to replace critical thinking from experienced practitioners. In fact, many CDRs have been directly compared against clinician gestalt or clinical practice, and they are not always better [1,2]. Additionally, some rules incorporate clinician gestalt, whereas the rule cannot even be applied unless the pre-test probability (based on the physician’s judgment of the likelihood of the disease) is below a pre-determined threshold [3]. Also, for a CDR to be useful to a practitioner, it must be practical. If a CDR is developed that has too many complicated variables, it is unlikely to be applied in a busy clinical environment [4].

Another caveat to the application of CDRs is that they must be applied appropriately. CDRs evolve through a process of derivation to validation to impact analysis of the tool. After the tool is derived (level 4 evidence), the tool is validated in a limited patient setting (level 3 evidence), then a broader validation setting (level 2 evidence), and finally, the impact of the tool is assessed (level 1 evidence) [5]. These levels are important to caution the novice learner against applying every CDR which has been derived and published automatically into their clinical practice. The tool must be validated in a patient population with similar characteristics to the practitioner’s patient population. For example, the tool may not perform the same (have the same sensitivity and specificity) if the prevalence of disease is different between the study and actual patient populations. Also, the practitioner must be familiar with a particular tool’s inclusion and exclusion criteria. If not, the tool could be misused. For example, if the tool was derived and validated for a patient population over the age of 18, it should not be inappropriately applied in a pediatric setting.

The practitioner must also understand the purpose of the CDR and whether it is a one-way or two-way rule. As noted by Green, for example, the Ottawa Ankle Rules are intended to be a two-way rule; if the patient meets the criteria, you do an X-ray; if they don’t meet the criteria, you do not do an X-ray [6]. There are two paths you can take after you apply your CDR. Alternatively, the pulmonary embolism rule-out criteria (PERC) demonstrate a one-way rule. This tool was developed to identify a subset of patients at very low risk for PE so that no further testing is needed. If the patient is “PERC positive,” this should not imply that further testing for PE, such as a D-dimer or CT angiogram of the chest, should be done. Whether or not additional testing should be done remains up to the practitioner and depends on many variables, including whether an alternate diagnosis is much more likely. PERC was designed to help “rule out” the diagnosis of PE, not “rule in.” This rule only guides you down one path: potentially, to do no testing; it makes no judgment as to what you should do if the patient is “PERC positive.”

In addition to CDRs, many risk stratification tools or scales have been used for serious conditions such as pulmonary embolism (PE) and acute coronary syndrome (ACS). Others have more recently been developed for use in the ED setting for common conditions such as congestive heart failure (CHF), chronic obstructive pulmonary disease (COPD), and transient ischemic attack (TIA) to identify patients at higher risk for acute severe complications [7]. From a practical perspective, the ED physician will often use these risk stratification devices to help determine which patients require admission. However, these tools are less prescriptive in that they are not rules that suggest what a practitioner should or should not do, but rather, they help the physician more objectively look at the risk for an individual patient. Then the practitioner must decide what level of risk they are comfortable with in regards to inpatient or outpatient management, which may greatly depend on the resources available in those environments. Most of the risk stratification tools encompass multiple variables with more complicated scoring systems; as they are not easily memorized, most of these would typically be used by ED physicians with real-time access to a computer or smartphone with appropriate apps.

Given the many pitfalls noted above of CDRs, the goals of using evidence-based medicine to reduce practice variability, maximize cost-effective use of resources, and help identify and diagnose high-risk conditions are important. It is equally important that the ED physician critically appraise these tools and selectively apply them in appropriate ways [8]. The remainder of this chapter will use case scenarios to review the most commonly used CDRs in the ED setting.

The useful FOAM reference MDCalc.com provides a summary of the most common tools that are being used with easy-to-use online calculators and additional information on inclusion and exclusion criteria, evidence basis for the tools, as well as pearls and pitfalls for each tool.

Orthopedic CDRs

Ottawa Knee, Ankle and Foot Rules

Case 1

A 28-year-old man presents to the ED with left ankle pain after twisting his ankle while playing basketball. He is able to bear weight and notes pain and swelling to the lateral aspect of the ankle (he points to just below the lateral malleolus). He denies weakness, numbness, or tingling and has no other injuries. On exam, he is neurovascularly intact. Edema and tenderness are noted slightly anterior and inferior to the lateral malleolus. There is no point tenderness to the distal posterior malleoli bilaterally.

Should you obtain an X-ray to check for a fracture?

Ottawa Ankle Rule

Pain in the malleolar zone and any one of the following:

Bone tenderness along the distal 6 cm of the posterior edge or tip of the tibia (medial malleolus), OR
Bone tenderness along the distal 6 cm of the posterior edge or tip of the fibula (lateral malleolus), OR
An inability to bear weight immediately and in the emergency department for four steps.

Ottawa Foot Rule

Pain in the midfoot zone and any one of the following:

Bone tenderness at the base of the fifth metatarsal, OR
Bone tenderness at the navicular bone, OR
An inability to bear weight immediately and in the emergency department for four steps.

Ottawa Knee Rule

Knee injury with any of the following:

Age 55 years or older
Tenderness at the head of the fibula
Isolated tenderness of the patella
Inability to flex to 90°
Inability to bear weight both immediately and in the emergency department (4 steps)

The Ottawa knee, ankle, and foot rules are some of the longest-standing and most widely accepted CDRs. These rules help practitioners identify patients with an extremely low risk of fracture such that X-rays do not need to be done, thus limiting the risks and costs of unnecessary testing. The sensitivity of these rules has been found to be 98.5-100% [9-11]. In impact study of the Ottawa knee rule, application of the rule decreased the use of knee radiography without patient dissatisfaction or missed fractures and was associated with reduced waiting times and costs. These rules have also been validated in pediatric populations with similar sensitivities (98.5-100%) [12-14].

Case 1 Discussion

Base on the Ottawa ankle rule, an X-ray is unnecessary. The patient can be treated supportively for an ankle sprain. When it comes to treating an ankle sprain, supportive care is typically the most effective approach. This involves several key strategies aimed at reducing pain and promoting healing. First and foremost, it’s important to follow the R.I.C.E. method:

Rest: Avoid putting weight on the injured ankle to prevent further damage. This might mean using crutches or a brace, especially in the initial days after the injury.
Ice: Applying ice packs to the ankle for 15-20 minutes every couple of hours can help reduce swelling and numb the pain. It’s crucial to wrap the ice pack in a cloth to protect the skin.
Compression: Using an elastic bandage or compression wrap around the ankle can help minimize swelling and provide support. It’s essential not to wrap it too tightly, as this could impede circulation.
Elevation: Keeping the ankle raised above the level of the heart can also help reduce swelling and improve blood flow to the area, speeding up the healing process.

In addition to the R.I.C.E. method, over-the-counter pain relievers like ibuprofen or acetaminophen can be used to manage pain and inflammation. Gradually reintroducing movement and gentle stretching exercises can aid in restoring strength and flexibility, but this should be done cautiously and ideally under the guidance of a healthcare professional. Physical therapy may also be beneficial in some cases, especially if the sprain was severe or if there are concerns about stability in the ankle after healing. A physical therapist can provide tailored exercises and techniques to regain strength and prevent future injuries. Overall, the goal of supportive treatment for an ankle sprain is to promote recovery while alleviating pain, allowing the patient to return to their normal activities as safely and quickly as possible.

Trauma CDRs

Canadian Cervical Spine and NEXUS Rules

Case 2

A 57-year-old man fell from a height of 12 feet while on a ladder. He did not pass out; he reports losing his footing. He fell onto a grassy area, hitting his head, and complains of neck pain. He did not lose consciousness and denies headache, blurry vision, vomiting, weakness, numbness or tingling in any extremities. He denies other injuries. He was able to get up and ambulate after the fall and came in by private vehicle. He has not had previous spine surgery and does not have known vertebral disease. On exam, he is neurologically intact with a GCS of 15, does not appear intoxicated, and has moderate midline cervical spine tenderness.

Should you obtain imaging to rule out a cervical spine fracture?

Canadian C-spine Rule

Age ≥ 65
Extremity paresthesias
Dangerous mechanism (fall from ≥ 3ft / 5 stairs, axial load injury, high-speed MVC/rollover/ejection, bicycle collision, motorized recreational vehicle)

NEXUS Criteria for C-spine Imaging

Focal neurologic deficit
Midline spinal tenderness
Altered level of consciousness
Intoxication
Distracting injury

Case 2 Discussion

Applying either criteria to this case would require C-spine imaging, as by CCR, the patient would meet the criteria for dangerous mechanism, and by NEXUS, the patient has midline tenderness to palpation.

Canadian CT Head Rule and NEXUS Head CT Instrument

Case 3

A 36-year-old woman slipped on ice and fell and hit her head. She reports loss of consciousness for a minute after the event, witnessed by a bystander. She denies having headaches. She denies weakness, numbness, or tingling in her extremities and no changes in vision or speech. She has not vomited. She remembers the event except for the transient loss of consciousness. She doesn’t use any blood thinners or have any known coagulopathy. On physical exam, she has a GCS of 15, no palpable skull fracture or scalp hematoma, no signs of a basilar skull fracture, normal mentation, and no neurologic deficits.

Should you obtain a CT head for this patient to rule out a clinically significant brain injury?

Canadian CT Head Rule

High Risk Criteria (rules out need for neurosurgical intervention)

GCS < 15 at two hours post-injury
Suspected open or depressed skull fracture
Any sign of basilar skull fracture (hemotypanum, Raccoon eyes, Battle’s sign, CSF oto or rhinorrhea)

Medium Risk Criteria (rules out clinically important brain injury)

Retrograde amnesia to event ≥ 30 minutes
Dangerous mechanism (pedestrian struck by motor vehicle, ejection from motor vehicle, fall from > 3 feet or > 5 stairs)

NEXUS Head CT Instrument

Evidence of significant skull fracture
Scalp hematoma
Neurologic deficit
Altered level of alertness
Abnormal behavior
Coagulopathy
Persistent vomiting
Age ≥65 years

The Canadian CT Head Rule (CCHR) only applies to patients with an initial GCS of 13-15, witnessed loss of consciousness (LOC), amnesia to the head injury event, or confusion [18]. The study was only for patients > 16 years of age. Patients were excluded from the study if they had “minor head injuries” that didn’t even meet these criteria. Patients were also excluded if they had signs or symptoms of moderate or severe head injury, including GCS < 13, post-traumatic seizure, focal neurologic deficits, or coagulopathy. The CCHR was designed to identify clinically important injuries and injuries requiring neurosurgical intervention. A potential limitation of its use could be if one works in a practice environment where the standard of care is to identify all intracranial injuries versus only those that require acute intervention.

The NEXUS Head CT Instrument was developed and validated more recently to address some of the limitations of rules, including the CCHR, where the inclusion and exclusion criteria may preclude its application in over one-third of blunt head injury cases, as well as other rules that focused only on pediatric populations such as PECARN [19-22]. The NEXUS Instrument is a one-way decision instrument for patients of all ages to identify low-risk patients who do not require CT imaging. The developers of the tool acknowledge that although its sensitivity is 100%, it is no better than the equal 100% sensitivity of clinical judgment [23]. Therefore, the benefit of its use is limited to “ruling out” significant intracranial injuries and reducing unnecessary testing. The developers also highlight that the use of CT imaging provides little information on concussions and post-concussive syndromes and that negative imaging does not preclude concussive injuries that can result in long-term brain injury and impairment.

Case 3 Discussion

By applying both rules to the above case, the patient does not require imaging despite her transient loss of consciousness after the injury.

PECARN Pediatric Head Trauma Algorithm

Case 4

A 20-month-old female was going up some wooden stairs, slipped and fell down four stairs, and hit the back of her head on the wooden landing at the bottom of the stairs. She did not lose consciousness and cried immediately. According to her parents, she was consolable after a few minutes and acted normally. She has not vomited. On exam, she is well-appearing, alert, and has a normal neurologic exam. She is noted to have a left parietal hematoma measuring approximately 4×4 cm.

Should you obtain CT imaging of this child to rule out clinically significant head injury?

PECARN Pediatric Head Trauma Algorithm

Age < 2

GCS < 15, palpable skull fracture, or signs of altered mental status
Occipital, parietal or temporal scalp hematoma; History of LOC≥5 sec; Not acting normally per parent or Severe Mechanism of Injury?

Age ≥ 2

GCS < 15, palpable skull fracture, or signs of altered mental status
History of LOC or history of vomiting or Severe headache or Severe Mechanism of Injury?

The PECARN (Pediatric Emergency Care Applied Research Network) Pediatric Head Trauma Algorithm was developed as a CDR to minimize unnecessary radiation exposure to young children. The estimated risk of lethal malignancy from a single head CT in a 1-year-old is 1 in 1000-1500 and decreases to 1 in 5000 in a 10-year-old [24]. Due to these risks, in addition to costs, length of stay and potential risks of procedural sedation, this CDR is widely employed given the frequency of pediatric head trauma ED visits. This CDR uses a prediction tree to assess risk, and unlike some other risk stratification tools, the PECARN group provides recommendations based on their definitions of acceptable risk levels. In the less than 2-year-old group, the rule was found to be 100% sensitive, with sensitivities ranging from 96.8%-100% sensitive in the greater than 2-year-old group [25,26].

This algorithm does have some complexity and ambiguity. It requires the practitioner to know what were considered signs of altered mental status and what were considered severe mechanisms of injury. In addition, certain paths of the decision tree lead to intermediate risk zones. In these cases, the recommendation is “observation versus CT,” allowing the ED physician to base their decision to image or not on numerous contributory factors, including physician experience, multiple versus isolated findings, and parental preference, among others.

Other pediatric head trauma CDRs have been derived and validated; however, in comparison trials, PECARN performed better than the other CDRs [1]. Of note, in this study, physician practice (without using a specific CDR) performed as well as PECARN with only slightly lower specificity.

Case 4 Discussion

The patient falls into an intermediate risk zone of clinically important brain injury. However, a sub-analysis of patients less than two years old with isolated scalp hematomas suggests that patients were at higher risk if they were < 3 months of age, had non-frontal scalp hematomas, large scalp hematomas (> 3cm), and had severe mechanism of injury [27]. Given the large hematoma in the case study patient and a severe mechanism of injury (a fall of > 3 feet in the under 2 yo age group), one should consider imaging due to these two additional higher risk factors.

PECARN Abdominal Trauma

Evidence of abdominal wall trauma/seatbelt sign or GCS < 14 with blunt abdominal trauma (if no, go to next point) – 5.4% risk of needing intra-abdominal injury intervention
Abdominal tenderness (if no, go to next point) – 1.4 % risk of intra-abdominal injury intervention
Thoracic wall trauma, complaints of abdominal pain, decreased breath sounds, vomiting – 0.7% risk of intra-abdominal injury intervention

The PECARN group has also developed a CDR, which was externally validated for pediatric blunt abdominal trauma [28,29]. This CDR uses a seven-point decision rule. If the patient does not have any of these findings, the patient would be considered “very low risk,” with a 0.1% risk of intra-abdominal injury intervention required. A study compared the PECARN CDR versus clinical suspicion and found that the CDR had significantly higher sensitivity (97.0% vs. 82.8% but lower specificity (42.5% vs. 78.7%) [30]. However, abdominal CTs were done in 33% of patients with clinical suspicion < 1%, meaning that even though clinical suspicion had higher specificity, this often did not translate into clinical practice. A recent external validation study supported the use of the CDR in decreasing CT use in pediatric patients at very low risk for clinically important intra-abdominal injuries [29].

NEXUS Chest Decision Instrument for Blunt Chest Trauma

NEXUS Chest was derived and validated for blunt chest trauma patients to identify very low-risk patients that do not require imaging [31,32]. It was developed only to rule out injury, not ruling it in. In other words, finding one or more NEXUS Chest criteria does not mean you must image that patient. The CDR creators suggest using NEXUS Chest only in patients for whom imaging was planned, then apply NEXUS Chest to determine whether one can safely forego imaging.

Pulmonary CDRs

Case 5

A 19-year-old female presents with sharp right flank pain and shortness of breath, which started suddenly the day before arrival. The pain is worse with deep inspiration but not related to exertion and not relieved with ibuprofen. She denies anterior chest pain, cough, and fever. She denies leg pain or swelling and recent travel, immobilization, trauma, or surgery. She has no anterior abdominal pain, no dysuria or hematuria, and no personal or family history of gallstones, kidney stones, or blood clots. She’s never had this pain before, has no significant past medical history, and her only medication is birth control pills. On exam, her vital signs are within normal range; she has normal cardiac and pulmonary exams, no costo-vertebral angle tenderness, no chest wall or abdominal tenderness, and no leg swelling.

Do you need to do any studies to evaluate this patient for a pulmonary embolism?

Pulmonary Embolism Rule-Out Criteria (PERC)

Age ≥ 50
Heart rate ≥ 100
O2 sat on room air < 95%
Prior history of venous thromboembolism
Trauma or surgery within 4 weeks
Hemoptysis
Exogenous estrogen
Unilateral leg swelling

The PERC CDR was originally derived and validated in 2004 and with a subsequent multi-study center validation in 2008 [33,34]. In the larger validation study, the rule was only applied in those patients with a pre-test probability of < 15%, therefore incorporating clinical gestalt before using the rule. As mentioned above, PERC is a one-way rule that tries to identify patients with low risk for pulmonary embolism (PE) so as not to require any testing. It does not imply that testing should be done for patients who do not meet criteria, and it is not meant for risk stratification, as opposed to the Wells and Geneva scores.

Case 5 Discussion

To apply the PERC CDR to the case, the ED physician pre-supposes a pre-test probability of < 15%. If the ED physician has a higher pre-test probability than that, the physician should not use the PERC CDR. If the ED physician in this case did indeed have a pre-test probability of < 15%, the case study patient would fail the rule-out due to her use of oral contraceptives. In that case, the ED physician would need to determine if he/she would do further testing, which could include a D-dimer, CT chest with contrast, ventilation/perfusion scan, or lower extremity Doppler studies to evaluate for deep vein thromboses (DVTs). The PERC CDR gives no guidance in this case.

Wells and Revised Geneva Score for Pulmonary Embolism (PE)

Wells’ Criteria for Pulmonary Embolism	Point Value
Clinical signs and symptoms of DVT	+3
PE is #1 diagnosis, or equally likely	+3
Heart rate > 100	+1.5
Immobilization at least 3 days, or Surgery in the Previous 4 weeks	+1.5
Previous, objectively diagnosed PE or DVT	+1.5
Hemoptysis	+1
Malignancy w/ Treatment within 6 mo, or palliative	+1

Geneva Score (Revised) for Pulmonary Embolism		Point Value
Risk factors	Age > 65	+1
	Previous DVT or PE	+3
	Surgery (under general anesthesia) or lower limb fracture in past 1 month	+2
	Active malignant condition	+2
Symptoms	Unilateral lower limb pain	+3
	Hemoptysis	+2
Signs	Heart rate < 75	0
	Heart rate 75 – 94	+3
	Heart rate ≥ 95	+5
	Pain on lower limb deep venous palpation and unilateral edema	+4

The Wells’ Criteria for PE is a risk stratification score with different point values assigned to different criterion. Its purpose is to identify patients with a lower PE risk to avoid unnecessary testing and the associated risks and costs [35]. The criteria have been validated in the ED setting [36]. The initial study used a three-tier model to classify patients as low, medium, or high risk. Subsequent studies have been done to apply a simplified version of the Wells’ Criteria and also to use the Wells’ Criteria along with D-dimer testing in a dichotomous manner (two-tier model) where a score of 4 or less (“PE Unlikely” group) combined with a negative D-dimer would achieve sufficiently low probability of PE so as not to pursue further work-up [37-39]. This two-tier model is supported by the American College of Physicians (ACEP) Clinical Guidelines [40]. A two-tier model using a cut-off of less than 6 for low-risk was also studied in pregnant patients with a negative predictive value of 100% [41].

The original Geneva score included chest radiography and an ABG, whereas the revised score (rGeneva) uses only clinical criteria [42]. A patient with an rGeneva score of 0-3 is considered low risk with a < 10% prevalence of PE. A score of 4-10 identifies intermediate-risk patients, and a score of 11+ is high risk (>60% prevalence or PE).

The Wells and rGeneva scores have been compared and found to have overall similar accuracy [43-45]. These PE risk stratification tools are meant to be applied to patients with concern for PE as a diagnosis. If PE is not under consideration, the tools should not be applied. Practically speaking, for many ED physicians, these tools are used to help risk stratify patients to identify those who are very low-risk such that no testing should be done, low to intermediate risk such that D-dimer testing would be a useful diagnostic tool, or high risk such that even if a D-dimer were negative, the post-test probability would remain high enough that further testing should be pursued. One recent study found that physician gestalt performed better than the Wells or rGeneva scores [45]. However, guidelines from the Clinical Practice Committee of the American College of Physicians (ACP) were published in 2015 that outline best practice advice including advocating that clinicians should use validated CDRs to estimate pre-test probability in patients in whom acute PE is being considered [46].

YEARS Algorithm for Pulmonary Embolism

The YEARS Algorithm was derived in 2017 and subsequently validated in studies in 2018 and 2021 [47-49]. It consists of the three most predictive criteria of the Well’s Score for PE and incorporates variable D-dimer thresholds, depending on the number of criteria fulfilled. It has the benefit of reducing the use of CT Pulmonary Angiogram by more broadly utilizing the results of D-dimer testing for selected patients. Additionally, a pregnancy-adapted algorithm was developed in 2019, which may be useful for clinicians struggling with the challenge of excluding PE in this sub-group, which has both a higher risk of PE and of radiation exposure to the fetus of performing the “gold standard” test which is considered a CT angiogram [50]. A recent study found that using the YEARS algorithm in combination with an age-adjusted D-dimer strategy was non-inferior to conventional diagnostic strategies and decreased chest imaging by 14% [51].

Pneumonia Severity Index (PSI) Score

The PSI Score estimates mortality for adult patients with community-acquired pneumonia (CAP). It is recommended as a Clinical Practice Guideline by the American Thoracic Society and Infectious Disease Society to use the PSI, in addition to clinical judgment, to determine the need for hospitalization in patients with CAP [52]. Although it has more variables than the CURB-65 Score, it was found to identify larger proportions of patients as low risk and found to have better discriminative power in predicting mortality. It includes variables such as age and sex as well as vital signs, co-morbidities, lab values, and imaging findings, which may limit its use in some resource-limited settings.

Ottawa COPD Risk Scale

The Ottawa COPD Risk Scale predicts 30-day mortality or serious adverse events in ED patients with COPD [53]. It was developed and validated to assist with disposition decisions to avoid admitting low-risk patients suitable for discharge and to avoid discharging high-risk patients [54]. It incorporates elements of the patient’s medical history and exam in the ED as well as testing, including an EKG, chest X-ray, hemoglobin, urea, and CO2.

Cardiac CDRs

Case 6

A 50-year-old male presents to the ED complaining of chest pain for two days. His pain is substernal and non-radiating. He described it as a tightness and is not related to exertion. He has no associated shortness of breath, nausea, or diaphoresis. No cough or fever. He’s never had this pain before. He has a history of hypertension but no other cardiac risk factors. His exam in the ED is normal, and his EKG and initial troponin are normal.

Does this patient require additional cardiac workup in the ED or admission to the hospital for further workup? Can this patient be safely discharged for outpatient follow-up?

HEART Score for Cardiac Events

HEART Score		Points
History	Highly suspicious	+2
	Moderately suspicious	+1
	Slightly suspicious	0
EKG	Significant ST depression	+2
	Non specific repolarization disturbance	+1
	Normal	0
Age	≥ 65	+2
	45-65	+1
	≤ 45	0
Risk Factors (include: hypercholesterolemia, hypertension, diabetes mellitus, cigarette smoking, positive family history, obesity)	≥ 3 risk factors or history of atherosclerotic disease	+2
	1-2 risk factors	+1
	No risk factors known	0
Troponin	≥ 3× normal limit	+2
	1-3× normal limit	+1
	≤ normal limit	0

The HEART Score is used to risk stratify chest pain patients in the ED to identify those at risk for major adverse cardiac events (MACE) within six weeks [55]. In the HEART Score, patients with a low risk (score between 0 and 3) indicate a less than 2% risk of major adverse cardiovascular events (MACE) within six weeks. The HEART Score differs from the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) scores as those scores measure the risk of death for patients with diagnosed acute coronary syndromes (ACS) rather than identifying patients who have cardiac-related chest pain in the first place [56,57]. Additionally, even with low TIMI scores for those diagnosed with ACS in the ED, there is still a 4.7% risk of a bad outcome [56]. This may be of little utility to the ED physician, who finds this risk level unacceptable.

Case 6 Discussion

This patient’s HEART Score is 3 if the physician considers the history “moderately suspicious.” The patient is at low risk for a major cardiac event in the next six weeks so that the ED physician could consider outpatient follow-up. Again, the risk stratification scores are not prescriptive, however. The clinician must make decisions based on his/her judgment, available resources, and comfort with certain levels of risk.

Emergency Department Assessment of Chest Pain Score (EDACS)

Similar to the HEART Score, the EDACS is used to further risk stratify patients with chest pain or other anginal symptoms requiring evaluation for possible acute coronary syndrome who may be potentially low risk and appropriate for early discharge from the emergency department [58]. It should only be applied in patients without ongoing chest pain. The score was 99-100% sensitive in the original derivation paper, and some studies showed it to be more sensitive than the HEART score and better at identifying more low-risk patients [59,60]. That said, a more recent meta-analysis reported a pooled sensitivity of only 96.1%, which may not be considered adequately sensitive by some providers or in some practice environments [61].

Ottawa Heart Failure Risk Score

The Ottawa Heart Failure Risk Scale (OHFRS) was derived in 2013 and validated in 2017 in Canada [62, 63]. It identifies ED patients with heart failure (HF) at high risk for serious adverse events, including death, MI, and the need for ICU/intubation. It is to be used for ED patients presenting with HF exacerbation who have responded to treatment in the ED to help clinicians determine whether admission might be warranted versus discharge for low-risk patients. The study authors looked at the performance of the CDR both with and without a Quantitative NT-proBNP diagnostic test. They found the CDR was valuable even without the availability of this test, which might improve its usefulness in different resource settings. That said, regional practice patterns should be considered when applying this score, such as differences overall in heart failure admission rates.

Atrial Fibrillation – the CHA2DS2-VASc and HAS-BLED Scores

The main clinical decision instruments regarding atrial fibrillation (afib) relate to whether or not to anticoagulate a patient in afib, weighing the risk of stroke without anticoagulation versus the risk of a major bleeding event. The CHA2DS2-VASc Score was developed in an era where Non-Vitamin K Antagonist Oral Anticoagulants (NOACs) are available in higher-resource settings, in addition to traditional warfarin, and in light of more recent evidence regarding the lack of efficacy and safety of aspirin for stroke prevention in afib [64,65]. The score is simple to use with variables of age, sex, and the patient’s medical history. The European Society of Cardiology guidelines recommend using the score to identify truly low-risk patients (0 for males or 1 for females) who do not need anticoagulation therapy [66]. The American Heart Association and American College of Cardiology guidelines also endorse using the CHA2DS2-VASc score as the stroke risk assessment tool of choice [67].

In addition to considering the risk of stroke in patients with afib, however, one also has to consider the risk of bleeding due to taking anticoagulants. Unfortunately, many risk factors for the former are also risk factors for the latter. The score that performs best for identifying the risk of bleeding is the HAS-BLED score [68-70]. The HAS-BLED authors note that while it does not identify absolute cut-offs for when not to use anticoagulants, it does help identify some risk factors that could be avoided or reversed, for example, by controlling hypertension or avoiding alcohol use or other medications that may predispose to bleeding. The decision of whether or not to anticoagulated a patient in afib is complex, but these CDRs provide some objective assessment of risk to inform decision-making and educate patients, and include them in shared-decision making.

Abdominal CDRs

Gastrointestinal Bleeding

Case 7

A 30-year-old male presents to the ED with nausea, vomiting, and epigastric discomfort for one day. He vomited multiple times, initially non-bloody, then developed some blood in the vomit during the last two episodes, which he quantified as a teaspoon in each. He denies melena or hematochezia. He has no diarrhea, fever, or syncope. He denies a history of liver or heart problems. On exam, he has normal vital signs with an initial blood pressure of 128/78 mmHg in the ED, and his abdomen is non-tender. His hemoglobin is 13.5, and his BUN is 5.

Does this patient need admission for further monitoring or evaluation of his upper GI bleed?

Glasgow-Blatchford Bleeding Score (GBS)

Hemoglobin < 13 for men or < 12 for women
BUN > 6.5
Initial systolic blood pressure < 110
Heart rate ≥ 100
Melena present
Recent syncope
Hepatic disease history
Cardiac failure

The Glasgow-Blatchford Bleeding Score (GBS) uses clinical information and some diagnostic testing to risk stratify upper GI bleeding patients[71,72]. It should not be used for lower GI bleeding patients or patients in whom the source of GI bleeding is unclear. A score of 0 is considered low risk. Any score higher than 0 is considered high risk for needing a medical intervention of transfusion, endoscopy, or surgery; therefore, any of the above criteria would be considered high risk. The tool assigns different point values to different gradations of the variables present to a possible highest possible score of 29. The GBS has performed better than other CDRs in predicting patients likely to need hospital-based intervention or are at risk for mortality [73].

Case 7 Discussion

The patient does not meet any of the GBS criteria and would be considered low-risk. Based on this risk stratification, the patient does not demonstrate any signs of lower GI bleeding and could likely be safely discharged home.

Oakland Score for Safe Discharge After Lower GI Bleed

Similar to the GBS Score, the Oakland Score helps identify low-risk patients with lower GI bleeding who are candidates for outpatient management. It is simple to use in most settings and includes age, sex, history, physical exam findings in the ED, and hemoglobin level [74,75].

Appendicitis - Alvarado Score and Pediatric Appendicitis Risk Calculator (pARC)

The Alvarado Score was developed to predict the likelihood of acute appendicitis in patients with abdominal pain [76]. It utilizes a combination of signs, symptoms, and a WBC count with differential to create a risk score. The score is best utilized to avoid unnecessary CT imaging in very low-risk patients or even potentially in very high-risk patients, particularly in low-resource settings where CT is not commonly available [77]. In a study comparing the Alvarado Score with another CDR for pediatric appendicitis, the Pediatric Appendicitis Score, the gestalt of a pediatric surgeon was found to be higher than either scoring system; however, the Alvarado Score may be useful in emergency settings without experienced clinicians [78].

The pARC was also developed specifically for pediatric patients aged 5-18 to identify risk for acute appendicitis [79]. It may be used to help determine the need for advanced imaging and identify low-risk patients who could be observed or discharged from the ED with follow-up or return precautions. The Alvarado Score relies on signs, symptoms, and the availability of WBC and neutrophil counts. In its validation study, it performed better than the Pediatric Appendicitis Score [80].

STONE Score for Uncomplicated Ureteral Stone

The STONE Score was developed to identify patients with a high likelihood of uncomplicated ureterolithiasis who could be managed empirically, minimizing the use of CT or possibly using a low radiation CT protocol [81-83]. It has simple demographic and symptom-based variables with the addition of a urine dipstick; it is, therefore, easy to apply across resource settings. A high STONE Score can decrease the likelihood of an alternative diagnosis to < 2%, potentially limiting unnecessary costs and radiation exposure associated with CT imaging. Ultrasound demonstrating hydronephrosis, in addition to the score, can further increase the likelihood of a stone [84]. Given the increased availability and use of point-of-care ultrasound (POCUS) in emergency settings, using the STONE score in combination with ultrasound is a prudent approach to avoid CT use. A caveat to the STONE score is that it should not be used in ill-appearing patients or those with signs or symptoms suggestive of a possible complicated ureterolithiasis, for example, if there is evidence of a concomitant infection.

Neurologic CDRs

Case 8

A 24-year-old woman presents with a headache that began three hours before arrival at the ED. The patient was at rest when the headache started. The headache was not described as a “thunderclap,” but it did reach maximum severity within the first 30 minutes. The headache is generalized and rated 10/10. She denies head trauma, weakness, numbness, and tingling in her extremities. She denies visual changes, changes in speech, and neck pain. She has not taken anything for the headache. She does not have a family history of cerebral aneurysms or polycystic kidney disease. She had a normal neurologic exam and normal neck flexion during the physical exam.

Should you do a head CT and/or a lumbar puncture to evaluate for a sub-arachnoid hemorrhage in this patient?

Ottawa SAH Rule

Investigate if ≥1 high-risk variable is present:

Age ≥ 40
Neck pain or stiffness
Witnessed loss of consciousness
Onset during exertion
Thunderclap headache (instantly peaking pain)
Limited neck flexion on exam

A CDR to determine the risk for subarachnoid hemorrhage (SAH) was derived and externally validated in a single study [85,86]. The purpose of the CDR was to identify individuals at high risk for SAH. This included those experiencing acute non-traumatic headaches that reached maximal intensity within one hour and had normal neurological examinations. Notably, the rule consists of several criteria for inclusion and exclusion, which the emergency department physician must understand. Additionally, it was derived only for patients aged 16 years and older. The study authors note that the CDR is to identify patients with SAH; it is not an acute headache rule. In the validation study, of over 5000 ED visits with acute headaches, only 9% of those met the inclusion criteria [86]. Additionally, clinical gestalt plays a significant role as the authors recommend not applying the CDR to individuals who are at ultra-high risk with a pre-test probability of SAH greater than 50%.

The Ottawa SAH Rule was 100% sensitive but did not reduce testing compared to current practice [85]. The authors state that the rule’s value would be standardizing physician practice and avoiding the relatively high rate of missed sub-arachnoid hemorrhages.

Case 8 Discussion

By applying the Ottawa SAH Rule, this patient is low risk and does not require further investigation for a SAH.

Canadian Transient Ischemic Attack (TIA) Score

The Canadian TIA Score was developed to identify patients at high risk for stroke in the next seven days after a TIA [87,88]. It is calculated based on clinical findings and ED testing, including an EKG, CT, platelet count, and glucose. The validation study also looked at the outcome of carotid endarterectomy or carotid artery stenting within seven days and found that the Canadian TIA Score outperformed the ABCD2 risk stratification tool. It is unclear yet how the application of the tool will impact ED practice, which will likely depend on many factors, including inpatient versus outpatient access to resources. The validation study authors suggest, “The optimal management pathway at the local or regional level can be determined on the basis of the expected risk at a given risk category (for example, same day computed tomography with routine follow-up for patients at low risk, computed tomography angiography and rapid follow-up for those at medium risk, and neurology consultation in the emergency department for those at high risk) [88].”

Other CDRs

San Francisco Syncope Rule

The San Francisco Syncope Rule uses five factors to identify patients who are at high risk of serious outcomes at seven days, including a history of congestive heart failure, hematocrit < 30%, abnormal EKG, shortness of breath, and systolic BP < 90mmHg at triage. In its initial derivation and validation studies, it was found to have 92% and 98% sensitivity, respectively [89, 90]. Its use is controversial, however, due to inconsistent validation studies where it has not performed as well [91,92]. A systematic review of the literature from 2011 suggested that “the probability of a serious outcome given a negative score with the San Francisco Syncope Rule was 5% or lower, and the probability was 2% or lower when the rule was applied only to patients for whom no cause of syncope was identified after initial evaluation in the emergency department [93].” Although there is no consensus on using this tool to safely discharge patients with syncope home if they do not meet these criteria, patients with criteria would be considered a higher risk, possibly warranting observation, admission, and/or further diagnostic studies.

Centor Score for Streptococcal Pharyngitis

The Centor Score is a risk stratification tool that looks at clinical criteria that suggest a greater likelihood of strep pharyngitis, which may prompt the ED physician to prescribe antibiotics [94]. It was initially designed for use in adults. However, a modified score has been validated for use in children > 2 years of age and adults that includes age criteria, as strep pharyngitis is a more common condition in children [95,96]. With a score of 4 or more points, the probability of strep is greater than 50%, and some would advocate for empiric antibiotics in this group to reduce suppurative (peritonsillar abscess, cervical lymphadenitis, and mastoiditis) and non-suppurative (e.g., acute rheumatic fever) complications of strep pharyngitis and shorten the duration of clinical symptoms and as well as to reduce transmission [97]. Rapid antigen detection tests have been found to have a sensitivity of between 70 and 90% and a specificity of ≥95% [97]. Some authors recommend rapid antigen detection testing (RADT) only for children with high clinical scores or if the results of the standard throat culture will not be available for more than 48 hours [97,98]. Studies have found that tonsillar exudates conferred the highest odds of strep infection [96,99].

Conclusion

Clinical Decision Rules (CDRs) or Instruments are increasingly being used to assist ED clinicians in navigating complex decision-making regarding diagnostic testing, clinical care, and disposition determination of emergency patients. These tools have the potential to supplement clinician gestalt, maximize the use of limited and expensive resources (e.g., inpatient beds, CTs), and minimize the use of possibly unnecessary costly or dangerous testing or treatments (e.g., CTs, anticoagulants).

While CDRs are a valuable adjunct to the emergency clinician, ED providers must carefully apply these based on validation cohorts representative of the clinician’s patient population and carefully consider the inclusion and exclusion criteria in the studies. CDRs should not supplant physician critical decision-making based on individualized patient-centered factors and circumstances including resources available, ability to establish outpatient follow-up, and shared-decision making with informed patients. CDRs may be particularly valuable for less experienced clinicians who are learning to identify patient characteristics, symptoms, physical exam findings, risk factors and testing that will help them diagnose and manage complex emergency patients in variable practice environments.

Author

Stacey Chamberlain

Dr. Stacey Chamberlain is a board certified emergency physician who is a Professor in the Department of Emergency Medicine at the University of Illinois at Chicago (UIC). She also serves as the Director of the Global Emergency Medicine Fellowship Program and the Co-Director of the Social Emergency Medicine Fellowship Program. In addition to her work in Emergency Medicine, she is the Director of Academic Programs at the UIC Center for Global Health. In this role, she oversees the Global Medicine (GMED) Program for UIC medical students and the graduate global health certificate programs. Dr. Chamberlain has done clinical, educational, public-health, disaster-response, and emergency medicine development work, including working with several globally-focused NGOs, spanning five continents. Her global health work focuses on capacity building in emergency care in Uganda.

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Coleman JJ, Carr BW, Rogers T, Field MS, Zarzaur BL, Savage SA, Hammer PM, Brewer BL, Feliciano DV, Rozycki GS. The Alvarado score should be used to reduce emergency department length of stay and radiation exposure in select patients with abdominal pain. J Trauma Acute Care Surg. 2018 Jun;84(6):946-950. doi: 10.1097/TA.0000000000001885. PMID: 29521805.
Pogorelić Z, Rak S, Mrklić I, Jurić I. Prospective validation of Alvarado score and Pediatric Appendicitis Score for the diagnosis of acute appendicitis in children. Pediatr Emerg Care. 2015 Mar;31(3):164-8. doi: 10.1097/PEC.0000000000000375. PMID: 25706925.
Kharbanda AB, Vazquez-Benitez G, Ballard DW, Vinson DR, Chettipally UK, Kene MV, Dehmer SP, Bachur RG, Dayan PS, Kuppermann N, O’Connor PJ, Kharbanda EO. Development and Validation of a Novel Pediatric Appendicitis Risk Calculator (pARC). Pediatrics. 2018 Apr;141(4):e20172699. doi: 10.1542/peds.2017-2699. Epub 2018 Mar 13. PMID: 29535251; PMCID: PMC5869337.
Cotton DM, Vinson DR, Vazquez-Benitez G, Margaret Warton E, Reed ME, Chettipally UK, Kene MV, Lin JS, Mark DG, Sax DR, McLachlan ID, Rauchwerger AS, Simon LE, Kharbanda AB, Kharbanda EO, Ballard DW; Clinical Research on Emergency Services and Treatments (CREST) Network. Validation of the Pediatric Appendicitis Risk Calculator (pARC) in a Community Emergency Department Setting. Ann Emerg Med. 2019 Oct;74(4):471-480. doi: 10.1016/j.annemergmed.2019.04.023. Epub 2019 Jun 19. PMID: 31229394; PMCID: PMC8364751.
Moore CL, Bomann S, Daniels B, Luty S, Molinaro A, Singh D, Gross CP. Derivation and validation of a clinical prediction rule for uncomplicated ureteral stone–the STONE score: retrospective and prospective observational cohort studies. BMJ. 2014 Mar 26;348:g2191. doi: 10.1136/bmj.g2191. PMID: 24671981; PMCID: PMC3966515.
Hernandez N, Song Y, Noble VE, Eisner BH. Predicting ureteral stones in emergency department patients with flank pain: an external validation of the STONE score. World J Urol. 2016 Oct;34(10):1443-6. doi: 10.1007/s00345-016-1760-3. Epub 2016 Jan 16. PMID: 26780732.
Wang RC, Rodriguez RM, Moghadassi M, Noble V, Bailitz J, Mallin M, Corbo J, Kang TL, Chu P, Shiboski S, Smith-Bindman R. External Validation of the STONE Score, a Clinical Prediction Rule for Ureteral Stone: An Observational Multi-institutional Study. Ann Emerg Med. 2016 Apr;67(4):423-432.e2. doi: 10.1016/j.annemergmed.2015.08.019. Epub 2015 Oct 3. PMID: 26440490; PMCID: PMC4808407.
Daniels B, Gross CP, Molinaro A, Singh D, Luty S, Jessey R, Moore CL. STONE PLUS: Evaluation of Emergency Department Patients With Suspected Renal Colic, Using a Clinical Prediction Tool Combined With Point-of-Care Limited Ultrasonography. Ann Emerg Med. 2016 Apr;67(4):439-48. doi: 10.1016/j.annemergmed.2015.10.020. Epub 2015 Dec 31. PMID: 26747219; PMCID: PMC5074842.
Perry JJ, Stiell IG, Sivilotti MA, et al. Clinical decision rules to rule out subarachnoid hemorrhage for acute headache. JAMA. 2013; 310(12): 1248-1255. doi:10.1001/jama.2013.278018.
Bellolio MF, Hess EP, Gilani W, VanDyck TJ, Ostby SA, et al. External validation of the Ottawa subarachnoid hemorrhage clinical decision rule in patients with acute headache. Am J Emerg Med. 2015 Feb; 33(2): 244-9. doi: 10.1016/j.ajem.2014.11.049. Epub 2014 Dec 3.
Perry JJ, Sharma M, Sivilotti ML, Sutherland J, Worster A, Émond M, Stotts G, Jin AY, Oczkowski WJ, Sahlas DJ, Murray HE, MacKey A, Verreault S, Wells GA, Stiell IG. A prospective cohort study of patients with transient ischemic attack to identify high-risk clinical characteristics. Stroke. 2014 Jan;45(1):92-100. doi: 10.1161/STROKEAHA.113.003085. Epub 2013 Nov 21. PMID: 24262323.
Perry JJ, Sivilotti MLA, Émond M, Stiell IG, Stotts G, Lee J, Worster A, Morris J, Cheung KW, Jin AY, Oczkowski WJ, Sahlas DJ, Murray HE, Mackey A, Verreault S, Camden MC, Yip S, Teal P, Gladstone DJ, Boulos MI, Chagnon N, Shouldice E, Atzema C, Slaoui T, Teitlebaum J, Abdulaziz K, Nemnom MJ, Wells GA, Sharma M. Prospective validation of Canadian TIA Score and comparison with ABCD2 and ABCD2i for subsequent stroke risk after transient ischaemic attack: multicentre prospective cohort study. BMJ. 2021 Feb 4;372:n49. doi: 10.1136/bmj.n49. Erratum in: BMJ. 2021 Feb 18;372:n453. PMID: 33541890; PMCID: PMC7859838.
Quinn JV, Stiell IG, McDermott DA, Sellers KL, Kohn MA, Wells GA. Derivation of the San Francisco Syncope Rule to predict patients with short-term serious outcomes. Ann Emerg Med. 2004 Feb; 43(2): 224-32.
Quinn J, McDermott D, Stiell I, Kohn M, Wells G. Prospective validation of the San Francisco Syncope Rule to predict patients with serious outcomes. Ann Emerg Med. 2006 May; 47(5): 448-54. Epub 2006 Jan 18. PubMed PMID: 16631985.
Birnbaum A, Esses D, Bijur P, Wollowitz A, Gallagher EJ. Failure to validate the San Francisco Syncope Rule in an independent emergency department population. Ann Emerg Med. 2008 Aug; 52(2): 151-9. Epub 2008 Feb 20. PubMed PMID: 18282636.
Snead GR, Wilbur LG. Can the San Francisco Syncope Rule predict short-term serious outcomes in patients presenting with syncope? Ann Emerg Med. 2013;62: 267-268.
Saccilotto RT, Nickel CH, Bucher HC, Steyerberg EW, Bingisser R, Koller MT. San Francisco Syncope Rule to predict short-term serious outcomes: a systematic review. CMAJ. 2011 Oct 18; 183(15): e1116–e1126. doi: 1503/cmaj.101326
Centor RM, Witherspoon JM, Dalton HP, Brody CE, Link K. The diagnosis of strep throat in adults in the emergency room. Med Decis Making. 1981; 1(3): 239-46.
McIsaac WJ, Kellner JD, Aufricht P, Vanjaka A, Low DE. Empirical validation of guidelines for the management of pharyngitis in children and adults. JAMA.2004; 291(13): 1587-1595. doi:10.1001/jama.291.13.1587.
Fine AM, Nizet, V, Mandl KD. Large-scale validation of the Centor and McIsaac Scores to predict group A streptococcal pharyngitis. Arch Intern Med. 2012 Jun 11; 172(11): 847–852. doi: 1001/archinternmed.2012.950.
Pichichero ME. Treatment and prevention of streptococcal tonsillopharyngitis. UpToDate.com. Available online at: http://www.uptodate.com/contents/treatment-and-prevention-of-streptococcal-tonsillopharyngitis?source=machineLearning&search=centor+criteria&selectedTitle=1~2&sectionRank=1&anchor=H9#H3. Accessed Dec. 2, 2015.
Wald ER, Green MD, Schwartz B, Barbadora K. A streptococcal score card revisited. Pediatr Emerg Care. 1998; 14(2): 109.
Ebell MH, Smith MA, Barry HC, et al. The rational clinical examination: does this patient have strep throat? JAMA 2000; 284: 2912– 2918.

Additional Online Resources

Emergency Medicine Cases podcast: Clinical Decision Rules and Risk Scales. This hour-long podcast discusses the overall use of CDRs and Risk Scales and how they are developed and used, with a discussion with Dr. Ian Stiell, the “father of clinical decision rules” from Ottawa, Canada. http://emergencymedicinecases.com/episode-56-stiell-sessions-clinical-decision-rules-risk-scales/
Agile MD app. You can download the AgileMD app for free and then download the EM Cases Summaries for free. Within EM Cases Summaries is a link to the “Ottawa CDRs and Risk Scales.” This includes shortcut to the Ottawa Ankle and Knee Rules, the Canadian C-spine and CT Head Rules, and the Ottawa COPD, Heart Failure, and TIA Risk Scores.
EmDOCS.net is a FOAMed initiative with a series of posts on Clinical Decision Rules.
There are numerous EM blogs and podcasts that provide education for EM trainees and physicians. Many are listed here: https://www.emra.org/about-emra/publications/recommended-blogs-and-podcasts/. The podcast EMCrit and EM:RAP in particular have episodes on Clinical Decision Rules.

Reviewed and Edited By

Arif Alper Cevik, MD, FEMAT, FIFEM

Prof Cevik is an Emergency Medicine academician at United Arab Emirates University, interested in international emergency medicine, emergency medicine education, medical education, point of care ultrasound and trauma. He is the founder and director of the International Emergency Medicine Education Project – iem-student.org, vice-chair of the International Federation for Emergency Medicine (IFEM) core curriculum and education committee and board member of the Asian Society for Emergency Medicine and Emirati Board of Emergency Medicine.

Cardiac Monitoring (2024)

November 23, 2024November 23, 2024 ~ iEM Education Project Team ~ Leave a comment

by Stacey Chamberlain

Definitions and Overview

Cardiac monitoring in the emergency setting is continuous monitoring of a patient’s cardiac activity in order to identify conditions that may require emergent intervention. These conditions include certain arrhythmias, ischemia and infarction, and abnormal findings that could signal impending decompensation. This chapter focuses specifically on cardiac monitoring or electrocardiography; additional methods of continuous hemodynamic monitoring in the emergency department (ED) include pulse oximetry, end-tidal CO2 monitoring, central venous pressure monitoring, and continuous arterial blood pressure monitoring. Of note, telemetry is the ability to do cardiac monitoring from a remote location; in practice, this is often a centralized system that might be located at a nursing station where multiple patients can be monitored remotely.

Cardiac monitoring differs from a 12-lead electrocardiogram in that it is done continuously over a period of time rather than capturing one moment in time in a static image. The benefit of this is that it captures transient arrhythmias and ectopic beats or monitors for changes over time. A disadvantage of cardiac monitoring is that typically, only 2 leads are displayed instead of a full 12 leads, giving a less comprehensive view of the heart and limiting its utility for looking for anatomic patterns. For example, on the 12-lead EKG, ED practitioners usually group the inferior, anterior, and lateral leads when looking for ischemic or infarct patterns. These may be less evident on a monitor with only two leads. Additionally, the static EKG allows the ED physician to carefully study it for subtle findings, for example, to make measurements of intervals, whereas in real-time monitoring, this is very difficult. In practice, both modalities are commonly used in conjunction for many ED patients.

The American Heart Association (AHA) published a consensus document in 2004 establishing practice standards for electrocardiographic monitoring in hospital settings, which was updated in 2017 [1,2]. These comprehensive documents outline the indications for cardiac monitoring, the specific skills required of the practitioner for cardiac monitoring, and specific ECG abnormalities that the practitioner should recognize. The 2017 update addressed the overuse of arrhythmia monitoring among certain populations, appropriate use of ischemia and QT-internal monitoring among select populations, alarm management, and documentation in electronic health records [2].

Cardiac monitoring is essential for those patients who are at risk for an acute, life-threatening arrhythmia and can also be used to evaluate for developing ischemia, response to therapy, and as a diagnostic tool. The AHA guidelines divide indications for cardiac monitoring in the inpatient setting into four classes based on varying degrees (level A, B, C) of evidence. Cardiac monitoring is considered indicated in patients in Class I. In Class IIa, it “is reasonable to perform” cardiac monitoring, whereas in Class IIb, it “may be considered.” For Class III, cardiac monitoring is not indicated as there is no benefit or there may actually be harm. Newer guidelines tailor the recommendations based on specific patient populations and whether the cardiac monitoring is for arrhythmia or continuous ST-segment ischemic monitoring [2]. Specific patient populations that are considered include patients with:

Chest pain or coronary artery disease.
Major cardiac interventions such as open heart surgery.
Arrhythmias.
Syncope of suspected cardiac origin.
After electrophysiology procedures/ablations.
After pacemaker or ICD implantation procedures.
Pre-existing rhythm devices.
Other cardiac conditions (acute decompensated heart failure or infective endocarditis).
Non-cardiac conditions (e.g., post-conscious sedation or post-non-cardiac surgery).
Specific medical conditions (e.g., stroke, imbalance of potassium or magnesium, drug overdose, or hemodialysis).
DNR/DNI status.

Table 1 lists Class I-III recommendations. The AHA Scientific Statement provides a more comprehensive and detailed list.

Table 1 – Select Indications for Cardiac Monitoring

Class I Indications	Early phase ACS or after MI
	After open-heart surgery or mechanical circulatory support
	Atrial tachyarrhythmias
	Symptomatic sinus bradycardia
	2^nd or 3^rd degree AV block (exception as noted below for asymptomatic Wenckebach)
	Congenital or genetic arrhythmic syndrome (e.g. WPW, Brugada, LQTS)
	After stroke
	With moderate to severe imbalance of potassium or magnesium
	After drug overdose
Class IIa and IIb Indications	Non-sustained VT
	Asymptomatic, significant bradycardia with negative chronotropic medications initiated
	After non-cardiac major thoracic surgery
	Chronic hemodialysis patients without other indications (e.g. hyperkalemia, arrhythmia)
Class III Indications	After non-urgent PCI without complications or after routine diagnostic coronary angiography
	Patients with chronic atrial fibrillation, sinus bradycardia, or asymptomatic Wenckebach who are hemodynamically stable and admitted for other indications
	Asymptomatic post-operative patients after non-cardiac surgery
	DNR/DNI patients when the data will not be acted on and comfort-focused care is the goal

Ischemia Monitoring

Continuous ST-Segment Ischemia Monitoring was highlighted in the 2017 AHA guidelines as a specific indication for cardiac monitoring for patients most at risk for ischemia. Older monitors may not have this capability, but more modern monitors are programmed with automated ischemia monitoring that identifies abnormal ST-segment elevation or depression; manufacturers do not automatically enable this capability, and it may be turned on or off. To reduce unnecessary alarms, it is recommended (IIa level) to enable this function only in high-risk patients in the early phase of ACS and to individualize which lead should be prioritized based on the coronary artery suspected to be affected by an ischemic process. High-risk patients would include those being evaluated for vasospastic angina, those presenting with MI, post-MI patients without revascularization or with residual ischemic lesions, and newly diagnosed patients with a high-risk lesion such as a left main blockage.

QTc Monitoring

QTc monitoring aims to assess the safety of QT-prolonging medications and avoid Torsade de Pointes (TdP). Most hospitals do not have fully automated continuous QTc monitoring, so QTc monitoring and measurements may need to be performed manually or semi-automated with digital calipers. Regardless of the method, in general, recommendations for QTc monitoring are for patients with specific risk factors for TdP who are started on anti-arrhythmic drugs with a known risk for TdP (e.g., dofetilide, sotalol, procainamide, quinidine, and others), patients with a history of prolonged QTc started on non-anti-arrhythmic drugs with risk for TdP, those undergoing targeted temperature management, specific electrolyte derangements, and select drug overdoses. As with ischemic monitoring, QTc monitoring is not universally recommended for all patients, so consulting the 2017 guidelines for select patient scenarios is best.

Rhythm Interpretation

One of the most critical skills of an ED physician is in interpreting both static EKGs and interpreting arrhythmias on a cardiac monitor. A skilled practitioner must be able to diagnose common arrhythmias and be well-versed in the management of acute arrhythmias, recognizing which arrhythmias necessitate immediate action and which are less worrisome. Table 2 from the 2004 AHA guidelines lists the specific arrhythmias that the ED physician must be able to recognize. How and whether to treat an arrhythmia depends on many factors. The AHA has established algorithms for specific rhythms, including ventricular fibrillation (v-fib)/pulseless ventricular tachycardia (v-tach) and pulseless electrical activity (PEA)/asystole, as well as for non-specific rhythm categories such as bradycardia and tachycardia [3]. Additionally, they have published algorithms for clinical scenarios, including cardiac arrest, acute coronary syndrome, and suspected stroke.

The first step in the assessment of any rhythm is a clinical assessment of the patient. The premier issue of concern is if the patient is perfusing vital organs. A quick survey of the patient assessing mental status and pulses is essential to determining management. The management of a patient with v-tach will be substantially different if the patient is unresponsive and pulseless versus if the patient is awake with good pulses. As another example, the physician can quickly distinguish artifact from v-fib on the cardiac monitor by assessing the patient, as v-fib is not a perfusing rhythm.

The initial assessment of tachyarrhythmias (heart rate > 100) is to determine if the rhythm is “narrow-complex” (i.e., a QRS duration < 0.12s) or “wide-complex” (i.e., a QRS duration of 0.12s or greater). A narrow complex rhythm is considered a supraventricular rhythm (originating above the ventricles). Supraventricular tachycardia is a generic term encompassing any narrow-complex tachycardias originating above the AV node. Colloquially, when many practitioners refer to “SVT,” however, they are referring to a specific subcategory of supraventricular tachycardia called AV nodal re-entrant tachycardia (AVNRT). Wide complex tachycardias either originate in the ventricles or could originate in the atria and have an associated bundle branch block. Different criteria have been developed to help the practitioner distinguish between ventricular tachycardia and an SVT “with aberrancy” (i.e., aberrant conduction either due to an accessory path such as in Wolff-Parkinson-White or with a bundle branch block), the most well known of which are the Brugada criteria [4,5]. Practically speaking, many ED practitioners will assume the more dangerous and potentially unstable rhythm (v-tach) until proven otherwise; of course, the clinical picture and the patient’s vital signs are of utmost importance in determining the management of these patients. An excellent summary of this issue with rhythm strip examples is provided on the FOAM site “Life in the Fast Lane” [6].

Table 2 – Specific Arrythmias (adapted from AHA Scientific Statement [1])

Normal rhythms
	Normal sinus rhythm
	Sinus bradycardia
	Sinus arrhythmia
	Sinus tachycardia
Intraventricular conduction defects
	Right and left bundle-branch block
	Aberrant ventricular conduction
Bradyarrhythmias
	Inappropriate sinus bradycardia
	Sinus node pause or arrest
	Non-conducted atrial premature beats
	Junctional rhythm
AV blocks
	1st degree
	2nd degree Mobitz I (Wenckebach) or Mobitz II
	3rd degree (complete heart block)
Asystole
Pulseless electrical activity (PEA)
Tachyarrhythmias
	Supraventricular	Paroxysmal supraventricular tachycardia (AV nodal reentrant, AV reentrant)
		Atrial fibrillation
		Atrial flutter
		Multifocal atrial tachycardia
		Junctional ectopic tachycardia
		Accelerated ventricular rhythm
	Ventricular	Monomorphic and polymorphic ventricular tachycardia
		Torsades de pointes
		Ventricular fibrillation
Premature complexes
	Supraventricular (atrial, junctional)
	Ventricular
Pacemaker electrocardiography
	Failure to sense
	Failure to capture
	Failure to pace
ECG abnormalities of acute myocardial ischemia
	ST-segment elevation, depression
	T-wave inversion
Muscle or other artifacts simulating arrhythmias

While each rhythm has distinctive management, it is worth noting for the novice learner that only v-fib and pulseless v-tach warrant asynchronized mechanical defibrillation (i.e. “shocking” the patient). Many students are stunned upon observing an asystolic cardiac arrest code to learn that shocking a “flatline” (i.e., asystolic) patient is an inappropriate treatment perpetuated by fictitious TV shows and movies. For unstable patients with arrhythmias but still have palpable pulses, synchronized cardioversion may be used.

Regarding medications, for certain rhythms and clinical scenarios, only vasopressor types of medications are used (e.g., epinephrine for asystole). For other rhythms and scenarios, antiarrhythmic medications are used (e.g., amiodarone for v-tach). Atrioventricular (AV) nodal blocking agents are often necessary for supraventricular tachyarrhythmias. One author suggests using a five “As” approach to treating emergency arrhythmias, keeping in mind the medications adenosine, amiodarone, adrenaline (epinephrine), atropine, and ajmaline [7]. Ajmaline is an antiarrhythmic that is not commonly used in English-speaking countries where procainamide is more common as an alternative to amiodarone for unstable v-tach.

Additional interventions may include pacemaker placement for symptomatic heart blocks. In many cases, the ED practitioner must also determine the underlying precipitant of the arrhythmia and tailor treatment to that cause. The emergency physician must familiarize himself with each rhythm and its unique management in any given clinical scenario.

At the end of this chapter, some good internet resources for the ED practitioner to practice interpreting EKGs and cardiac rhythms are provided.

Case Example

A 44-year-old male patient with a history of hypertension and end-stage renal disease on hemodialysis presents with shortness of breath after missing dialysis for 6 days. He reports gradual onset shortness of breath associated with orthopnea and increased lower extremity edema. He denies chest pain or palpitations. He does not have any cough or fever. On physical exam, he is in no distress, afebrile with a heart rate of 60, respiratory rate of 20, blood pressure of 140/78 mmHg, and oxygen saturation of 98% on room air. He has a regular rate and rhythm without murmurs and has crackles bilaterally to the inferior 1/3 of the lung bases and 1+ pitting edema of the bilateral lower extremities.

You decide to get an EKG, which shows the following:

You send a blood chemistry test, place the patient on a cardiac monitor, and one hour later note the following on the monitor:

What are the indications for cardiac monitoring in this patient? What EKG abnormalities do you see? What does the rhythm strip show? What is the treatment?

Case Discussion

The ED practitioner should recognize potentially life-threatening conditions that a patient who has missed hemodialysis is at risk for are fluid overload (leading to pulmonary edema) and hyperkalemia. This patient could be considered to meet the Class I monitoring criteria for “needing intensive care” and possibly with “pulmonary edema”; however, even if the patient had no symptoms, the patient is indeed at risk for an acute life-threatening arrhythmia that would necessitate cardiac monitoring.

The EKG demonstrates peaked T waves indicative of acute hyperkalemia. Given the clinical picture of missed dialysis and the peaked Ts on the EKG, the ED physician should immediately initiate treatment for acute hyperkalemia without waiting for a confirmatory blood test (unless immediate point-of-care tests are available). If the patient’s hyperkalemia progressed, the patient could develop QRS widening with the morphology as shown on the rhythm strip called a “sine wave.” This dangerous finding could precipitously deteriorate into a life-threatening arrhythmia such as pulseless v-tach with cardiac arrest and should prompt immediate action. It is important to note that hyperkalemia can manifest in a variety of different EKG findings and does not always follow a consistent pattern from peaked Ts to QRS widening to sine waves; therefore, the patient should be treated at the first indication of any hyperkalemia-related EKG changes.

Conclusions

Cardiac monitoring is an important tool to monitor patients at risk for acute arrhythmias (including those at risk specifically for TdP) and acute or worsening cardiac ischemia. It can be helpful to immediately identify patients with life-threatening arrhythmias who need immediate intervention, to assess the response to medications for arrhythmias, and to help exclude arrhythmias as a likely etiology of a patient’s symptoms (e.g., a patient with syncope) [9]. Given the limited resources and the lack of benefits for many patients, the purpose and duration of cardiac monitoring should be carefully considered. Overuse can not only waste resources but can also contribute to alarm hazards, including “alarm fatigue,” where clinicians are barraged by so many false or nonactionable alarm signals that they become desensitized and do not respond to real events. Therefore, appropriate use and staff education are critical to maximizing the benefits of cardiac monitoring.

Author

Stacey Chamberlain

Listen to the chapter

2018 version of this topic – https://iem-student.org/cardiac-monitoring/

References

Drew BJ, Califf RM, Funk M, Kaufman ES, Krucoff MW, et al. AHA Scientific Statement: Practice Standards for Electrocardiographic Monitoring in Hospital Settings. Circulation. 2004; 110: 2721-2746. doi: 10.1161/01.CIR.0000145144.56673.59
Sandau KE, Funk M, Auerbach A, Barsness GW, Blum K, Cvach M, Lampert R, May JL, McDaniel GM, Perez MV, Sendelbach S, Sommargren CE, Wang PJ; American Heart Association Council on Cardiovascular and Stroke Nursing; Council on Clinical Cardiology; and Council on Cardiovascular Disease in the Young. Update to Practice Standards for Electrocardiographic Monitoring in Hospital Settings: A Scientific Statement From the American Heart Association. Circulation. 2017 Nov 7;136(19):e273-e344. doi: 10.1161/CIR.0000000000000527. Epub 2017 Oct 3. PMID: 28974521.
ACLS Training Center. Algorithms for Advanced Cardiac Life Support 2015. Dec 2, 2015. Accessed at: https://www.acls.net/aclsalg.htm, Dec 10, 2015.
Wellens HJJ. Ventricular tachycardia: diagnosis of broad QRS complex tachycardia. Heart2001;86:579-585 doi:10.1136/heart.86.5.579.
Brugada P, Brugada J, Mont L, Smeets J, Andries EW. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation. 1991; 83: 1649-1659. doi: 10.1161/01.CIR.83.5.1649
Burns E. VT versus SVT with aberrancy. Life in the Fast Lane. Accessed at: http://lifeinthefastlane.com/ecg-library/basics/vt_vs_svt/, Dec 10, 2015.
Trappe H-J. Concept of the five ‘A’s for treating emergency arrhythmias. J Emerg Trauma Shock. 2010 Apr-Jun; 3(2): 129–136. doi: 10.4103/0974-2700.62111
Ramzy M. Duration of Electrocardiographic Monitoring of Emergency Department Patients with Syncope. REBEL EM blog; June 13, 2019; Available at: https://rebelem.com/duration-of-electrocardiographic-monitoring-of-emergency-department-patients-with-syncope/.

Additional Online Resources

Arrhythmias practice strips and skills http://www.practicalclinicalskills.com/arrhythmia.aspx
ECG library. Life in the Fast Lane http://lifeinthefastlane.com/ecg-library/
ECG examples. ECGPedia. http://en.ecgpedia.org
FOAMEd summary of use of inpatient continuous electrocardiographic monitoring: Chief Corner: Continuous Electrocardiographic Monitoring; June 22, 2018; Accessed May 19, 2023 at: https://www.thesilverfridge.com/blog/2018/6/22/chief-corner-continuous-electrocardiographic-monitoring

Reviewed and Edited By

Arif Alper Cevik, MD, FEMAT, FIFEM

Prof Cevik is an Emergency Medicine academician at United Arab Emirates University, interested in international emergency medicine, emergency medicine education, medical education, point of care ultrasound and trauma. He is the founder and director of the International Emergency Medicine Education Project – iem-student.org, vice-chair of the International Federation for Emergency Medicine (IFEM) core curriculum and education committee and board member of the Asian Society for Emergency Medicine and Emirati Board of Emergency Medicine.

Delirium and Dementia (2024)

November 12, 2024November 13, 2024 ~ iEM Education Project Team ~ Leave a comment

by Lo Lucian Simeon, Ngai Oona Wing Yan, & Lo Yat Hei

You have a new patient!

Adam is a 76-year-old man who is brought to the emergency room by his family members, complaining of a lack of responsiveness and general lethargy. According to his family, Adam has been having increasing memory problems in the past year and has gotten lost while walking around his neighborhood multiple times. His personality has changed and becomes agitated easily. He is also becoming less attentive to personal hygiene, wearing dirty clothes for several days, and having several episodes of urinary incontinence. Today, his family members noted that he had fallen asleep multiple times and showed no interest in his food. He did not respond when addressed by name. At the time of presentation, he is conscious, but appears lethargic and uncooperative. He cannot tell where he is and does not seem to recognize his family members. His past medical history includes hypertension and hypercholesterolemia. He is taking amlodipine and simvastatin.

Vitals show a heart rate of 108 beats per minute, blood pressure 154/84 mmHg, temperature 36.7℃, respiratory rate 20 breaths per minute, and an oxygen saturation of 98% on room air. His Glasgow coma score is E4V4M6.

What do you need to know?

Importance

Dementia and delirium are two medical conditions that significantly impact the health and well-being of older adults and their families. In this case, Adam’s symptoms suggest that he may be experiencing one or both of these conditions, and it is important to understand their relevance in clinical practice.

Dementia is defined as an acquired global decline in cognitive function, affecting one’s memory, language, learning, and behavior without impairment of consciousness. Dementia is associated with a gradual, progressive decline. It is a leading cause of disability and dependence among older adults, with advancing age being one of the most significant risk factors [1]. With the global population aging, the number of individuals living with dementia is expected to rise significantly. The World Health Organisation estimates that 47 million people worldwide live with dementia, and this number is expected to triple by 2025 [2].

Delirium, conversely, is a clinical syndrome characterized by an acute state of confusion, inattention, and cognitive impairment. It can occur in people of any age, but is particularly common among the older population and hospitalized patients [1]. Delirium can wax and wane over time, unlike dementia, which is more progressive and persistent.

Dementia and delirium pose a tremendous burden not only on patients and caregivers, but also on our healthcare system and society. Therefore, understanding the significance of dementia and delirium is crucial in clinical practice. Identifying and managing these conditions early improves clinical outcomes and optimizes quality of life.

Epidemiology & Pathophysiology

Dementia is a condition that is more commonly seen in older individuals, with the incidence increasing from the age of 65. An exception is frontotemporal dementia, a rare type of dementia that is usually diagnosed from the age of 40 to 60. The most prevalent type of dementia is Alzheimer’s disease, which accounts for 60-80% of all cases. Other neurodegenerative dementias, such as vascular dementia, dementia due to Lewy bodies, Parkinson’s disease, and frontotemporal dementia, account for the remaining cases [3].

The underlying pathophysiology of dementia varies depending on the type and subtype, with most types involving damage to neurons and their connections in the brain. Abnormal protein accumulation is a common feature for many types of dementia, including amyloid and tau in Alzheimer’s disease, Lewy bodies with alpha-synuclein protein in Lewy body disease, and mutations causing the deposition of TDP-43 and tau proteins in frontotemporal dementia. Other factors, such as ischemic injury, HIV infection, and alcohol consumption, can also lead to cytotoxic processes in the brain and contribute to the development of dementia [4].

On the other hand, the epidemiology of delirium is more complex as it varies depending on age and underlying medical conditions. Although delirium is more prevalent in older individuals, with rates increasing after the age of 70, it is also common in younger patients suffering from chronic illnesses such as cardiovascular and renal comorbidities, dementia, or psychiatric illnesses [5].

The pathophysiology of delirium can result from various physiological and structural lesions in the brain. While its mechanisms are not fully understood, delirium can be caused by neurotransmitter imbalances, brain lesions involving the ascending reticular activating system, as well as disrupted blood-brain barrier function that causes the leakage of neurotoxic agents into the brain. Patients with impaired cholinergic transmission, such as those with Alzheimer’s disease, are particularly susceptible to delirium caused by medication use. Additionally, delirium can result from alcohol abuse, drug withdrawal, mental illnesses, psychosocial stress, and sleep deprivation [6].

Epidemiological and pathophysiological data on dementia and delirium allow physicians to identify individuals at risk and intervene appropriately. Since the development of dementia and delirium are multifactorial and the pathophysiology is variable among patients, evaluating and treating delirium and dementia is based on clinical gestalt and the presumed underlying cause.

Medical History

Dementia and delirium are two diagnoses that must be considered in elderly patients presenting with cognitive change to the emergency department. Differentiation between the two conditions is based on features noted in the history and physical examination. Table 1 lists symptoms that can help differentiate between the two conditions.

Delirium typically presents with sudden onset of impaired awareness, confusion, clouding of consciousness, and disturbances of perception (e.g., illusions or hallucinations). Delirium should be suspected when there is an acute deterioration in behavior, cognition, and daily functioning [7]. Delirious patients usually have short-term memory issues and may be disoriented by time and place. Abnormalities of cognition and behavior can fluctuate over brief periods. The level of awareness may range from hypervigilant and agitated to blunt and unreactive. The patient’s speech may be incoherent, nonsensical, or tense. The patient usually has no discernible focal neurological defect [8].

Dementia has various presentations according to the specific types, but symptoms often overlap. Alzheimer’s dementia, the most common type, presents with a history of a chronic, steady decline in cognitive ability, especially memory. It is often associated with difficulties in social relationships, activities of daily living, and work. During the early stages of dementia, clinical presentations can be quite subtle, and patients may try to hide their cognitive impairments [9].

Patients who present to the emergency department with symptoms of dementia are most likely in the later stages of disease progression. Acute presentation of dementia is possible in vascular dementia, and this subtype may present with symptoms of focal neurological deficit. Patients who are demented typically do not present with any impairment of consciousness. However, acute episodes of delirium can be superimposed on patients who have dementia. For example, Lewy body dementia can present with fluctuating levels of consciousness. Diagnosing uncommon variants poses a challenge to emergency physicians and is often done only after referral to a neurologist [10].

Obtaining a thorough history is essential in diagnosing delirium and dementia. Unfortunately, delirious or demented patients are often disoriented and cognitively impaired, resulting in the inability to provide accurate information about their condition. A detailed history should be obtained from family, caregivers, and healthcare staff (nurses, healthcare assistants, and other allied health professionals).

Important features to note during history are the onset of symptoms, factors that worsen or improve symptoms, drug or alcohol use, pre-existing endocrine or psychiatric disorders, exposure to toxins or traumatic injury, social history, and previous similar episodes of confusion or altered mental status. Drug history is particularly important as the use of drugs that impair cognition (e.g., analgesics, anticholinergics, psychotropic medications, and sedatives) may explain the presenting symptoms.

Determining the onset of symptoms, in particular, for patients with dementia, can be difficult due to the gradual nature of the disease. Questions like, “When did you first notice the memory loss?” and “How has the memory loss progressed since then?” can give a general idea on the patient’s current condition. The patient’s social history, especially work, educational history, and ability to conduct activities of daily living, can help establish a baseline for the patient.

Table 1: Key symptoms to look for to differentiate between delirium and dementia during history taking [11]

	Delirium	Dementia
Onset	Acute	Insidious/chronic
Course	Fluctuating	Progressive
Duration	Days to weeks	Months to years
Consciousness	Altered	Clear
Alertness	Impaired	Normal, except for in severe cases of dementia
Behaviour & Speech	Agitated/withdrawn/ depressed/combination of symptoms	Intact early on

Typical presentations of dementia of various type

Dementia manifests in various forms, each with distinct characteristic presentations. Alzheimer’s dementia typically involves memory loss, mood instability, apathy, and may include depressive or paranoid features. Additionally, patients may experience apraxia, anosognosia, sensory inattention, and progressive personality and intellectual deterioration. Vascular dementia, on the other hand, often has an abrupt onset with a stepwise deterioration and a fluctuating course. It is marked by slowed thinking, difficulties in organization, preserved personality and insight, and may include focal neurological deficits. Dementia with Lewy bodies is characterized by Parkinsonism, cognitive and alertness fluctuations, as well as visual hallucinations, delusions, and autonomic dysregulation. Frontotemporal dementia commonly occurs at a younger age, typically between 40 and 60 years, and is associated with early personality changes, disinhibition, and overactivity.

Physical Examination

The physical exam of the dementia and delirium patient starts with taking vital signs, assessing the airway, breathing, circulation, and performing a focused neurological exam. Calculating the Glasgow Coma Score (GCS) and checking blood glucose should be checked on all patients with behavioral or cognitive changes.

Table 2 lists the key signs of differentiating delirium and dementia. Key features such as acute onset, fluctuations in awareness, orientation, and consciousness, cognitive decline, and potential sensory disruptions can help distinguish delirium from dementia. This includes declining memory function, language ability, and judgment. When in doubt, the general rule of thumb is to assume the patient is having an episode of delirium and try to rule out the common causes. This rule can be applied even for patients with known psychiatric illnesses like depression and dementia, as they are also susceptible to delirium superimposed on their existing condition.

Table 2: Key signs to look for to differentiate between delirium and dementia during physical exam [11]

	Delirium	Dementia
Conscious level	Abnormal	Normal
Psychomotor changes	Increased/decreased	Often normal
Reversibility of symptoms	Reversible usually	Irreversible

On neurological examination, look for signs of stroke, parkinsonism, gait abnormalities, and abnormal eye movements. Dementia caused by Alzheimer’s disease generally has no sensory or motor deficits. Whereas for delirium, it is essential to identify any co-existing neurological disorders that may cause a presentation of delirium. Special tests for gait, daily living, and cognitive function assessment should be done to assess the severity of the patient’s condition. A thorough physical examination of other systems should also be conducted to look for signs of encephalopathy and drug and alcohol abuse.

Use the physical exam to help identify any exacerbations of an underlying medical illness (e.g., signs of diabetic ketoacidosis in a diabetic patient) and to evaluate for signs that may reveal an underlying cause. For example, a high fever, low blood pressure, rapid or slow heart rate, difficulty breathing, severe pain, or malaise may indicate delirium caused by an infection, sepsis, or shock that requires immediate medical attention. Severe thirst, nausea, and vomiting may indicate dehydration or electrolyte disturbances that should be promptly treated. Signs of unresponsiveness, difficulty breathing, or seizures may indicate intracranial bleeding or alcohol or drug intoxication. Since these conditions can cause delirium and have symptoms that overlap with dementia, it is important to prioritize and appropriately manage these urgent and life-threatening cases [12].

Alternative Diagnoses

Table 3 shows alternative diagnoses to consider when evaluating for dementia and delirium. In patients presenting with altered cognitive levels, life-threatening causes that need to be ruled out include hypoglycemia, electrolyte abnormalities such as hyponatremia and hyperkalemia, dehydration, stroke, intoxication/overdose, encephalopathy, cerebral infection, sepsis, and shock.

Psychiatric disorders such as psychosis, schizophrenia, and depression are among the list of differential diagnoses that could present with similar symptoms. Frequently, in patients with delirium, they do not have any previous history of psychiatric illness. In delirium, hallucinations and illusions are acute or subacute and fluctuate over time. In addition, the patient has impaired memory, orientation, and judgment, as well as clouding of consciousness. Elderly patients with a depressed mood, hopelessness, and suicidal ideation may be suffering from “pseudodementia” (false dementia). When the symptoms of depression are treated, the dementia-like condition usually resolves itself [13].

Investigations, such as bloodwork, toxicology screening, biochemical tests, and imaging can help determine a delirium patient’s underlying cause and identify an alternative diagnosis. Investigations to consider are listed below under “Acing diagnostic testing.”

Table 3: Alternative diagnoses of altered cognitive level [14]

Central nervous system: brain abscess, cerebral neoplasm, encephalitis, intracranial haemorrhage, meningitis, normal pressure hydrocephalus, variant Creutzfeldt-Jakob Disease and bovine spongiform encephalopathy

Electrolyte: hyper/hypocalcemia, hyperkalemia, hyper/hyponatremia

Dehydration

Environmental: heat stroke, snake bite

Infective: sepsis, rabies, malaria

Metabolic: diabetic ketoacidosis, hyperosmolar hyperglycemic nonketotic coma, hypoglycemia, hypothyroidism, uremia, hepatic encephalopathy

Nutrition deficiency: folate, thiamine (Wernicke encephalopathy), vitamin B12,

Poisoning: amphetamine, anticholinergic, antidepressant, cocaine, hallucinogen, lithium, tricyclic antidepressant, valproate, withdrawal

Psychiatric: depression, psychosis

Transient global amnesia

Acing Diagnostic Testing

Initial Investigations

Complete Blood Count with Differential: This test is critical for assessing overall health and detecting a variety of conditions, such as infections, anemia, and blood disorders. The differential component provides a breakdown of different types of white blood cells, which can help to identify specific types of infections (e.g., bacterial or viral) and help diagnose other hematological disorders like leukemias or other abnormalities in blood cell production.
Electrolyte Panel: The electrolyte panel is essential for assessing the balance of minerals in the body, such as sodium, potassium, calcium, and chloride. Disturbances in these levels can indicate a variety of issues. For instance, hyponatremia (low sodium) can be a sign of dehydration or kidney dysfunction, while hyperkalemia (high potassium) could indicate kidney failure or metabolic acidosis. These imbalances can have significant effects on muscle function, nerve transmission, and overall cellular processes.
Liver Function Test: Liver function tests are crucial in diagnosing liver diseases such as hepatitis, cirrhosis, and alcoholic liver disease, as well as conditions like hepatic encephalopathy. These tests measure the levels of enzymes, proteins, and substances like bilirubin, which indicate how well the liver is working. Abnormal results may suggest liver damage, bile duct obstruction, or liver dysfunction that can lead to brain symptoms, especially in severe cases of hepatic encephalopathy.
Renal Function Test: This test evaluates how well the kidneys are filtering waste from the blood. It includes measurements like serum creatinine and blood urea nitrogen (BUN), which are key indicators of kidney function. Elevated levels may suggest renal failure, and abnormalities in these values can also help diagnose uremia, a condition where kidney dysfunction leads to the accumulation of waste products in the blood, potentially affecting multiple organ systems.
Blood Sugar: Blood sugar levels are measured to rule out conditions like hypoglycemia (low blood sugar) and hyperglycemia (high blood sugar). In patients with diabetes, particularly in cases of diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemic nonketotic syndrome (HHNS), these levels can be critically elevated and require immediate treatment. Monitoring blood sugar is essential for managing and preventing complications related to these conditions.
Urine Dipstick: The urine dipstick test is a quick and convenient method for identifying potential urinary tract infections (UTIs), which are a common cause of sepsis in elderly patients. It can detect substances like white blood cells, nitrites, and protein in the urine, all of which suggest infection or inflammation. Early detection of UTIs is crucial, as they can quickly progress to sepsis if untreated.
Chest X-ray: A chest X-ray is an important imaging tool for identifying lung consolidation, a hallmark of chest infections such as pneumonia. Pneumonia is another common cause of sepsis, particularly in elderly patients with weakened immune systems. The X-ray can also help detect other lung-related issues like fluid accumulation, pulmonary edema, or lung tumors that could complicate the clinical picture.
CT Scan of the Brain: A CT scan of the brain is used to identify structural abnormalities, including the presence of tumors, stroke, or brain hemorrhages. It is also used to detect cerebral atrophy (shrinkage of brain tissue) and ventricular enlargement, which can be indicative of conditions like dementia. This imaging modality is important in diagnosing neurological disorders and guiding further management for patients with cognitive or neurological impairments.

Further Investigations If A Differential Is Suspected

Urine and Blood Toxicology: This test is performed to detect the presence of drugs, alcohol, or other toxic substances in the body. Toxicology screens can identify intentional or unintentional overdoses, exposure to toxic substances, and drug or alcohol misuse. In cases of altered mental status or cognitive impairment, toxicology testing helps to rule out substance-induced confusion or delirium, which can mimic other medical or psychiatric conditions.
Thyroid Function Test: Thyroid hormones play a significant role in regulating metabolism and overall brain function. Abnormal thyroid function, whether hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid), can lead to symptoms of cognitive impairment, mood changes, and lethargy. A thyroid function test measures levels of thyroid hormones (such as TSH, T3, and T4) to determine if an imbalance is contributing to the patient’s cognitive or neurological symptoms, which can be reversible with appropriate treatment.
Vitamin B12 and Folate Levels: Both Vitamin B12 and folate are essential for nerve function and the production of red blood cells. A deficiency in either of these vitamins can lead to cognitive impairment, memory loss, and other neurological symptoms. Vitamin B12 deficiency, in particular, is known to cause a condition called subacute combined degeneration of the spinal cord and brain, which can lead to irreversible damage if left untreated. Checking these levels helps to rule out nutritional deficiencies as a potentially treatable cause of cognitive decline.
Bacteriology and Viral Detection: Infection-related causes of cognitive impairment or altered mental status may be identified through bacteriology and virology testing. This typically involves blood and urine microscopy, as well as culture tests to detect bacterial, viral, or other pathogenic organisms. Infections, especially in elderly or immunocompromised patients, can lead to sepsis or encephalitis, which can significantly impact cognitive function. Identifying and treating an underlying infection can prevent further deterioration and improve cognitive outcomes.

Risk Stratification

Cognitive assessment tools help identify and grade abnormal cognitive performances. They can also be integrated into the emergency medicine physical exam to screen patients for mild cognitive impairment or dementia.

Instead of an extended mental status examination or formal neuropsychological testing, more focused screening tools are more relevant and feasible for use in the emergency department [15]. Examples of screening tools validated for use in the emergency department include the abbreviated mental test score (AMTS) and its abbreviated four-item version (AMT4), the mini-mental state examination (MMSE), and the Montreal Cognitive Assessment (MoCA). They assess a broad range of cognitive domains, including memory, language, and orientation. These tests are designed to be administered in 15 minutes or less and have pre-determined cut-off scores to help distinguish patients with normal cognitive function and those with impaired cognitive function [16].

These screening tools are intended to help screen individuals who may require more extensive neurological assessments. They should only be used as a reference and must be integrated with history and physical examination findings for a holistic approach. Multiple factors, such as altered mood, disorientation, and education level, can affect the accuracy of these screening tools.

Table 4: Abbreviated mental test score four-item version (AMT4)

Ask the patient to state each of the following. A score less than 4 should prompt further cognitive screening.
Age	Correct (+1) / Incorrect (0)
Date of birth	Correct (+1) / Incorrect (0)
Place	Correct (+1) / Incorrect (0)
Year	Correct (+1) / Incorrect (0)

Management

The ABCDE approach is used for the initial management of patients with cognitive changes, behavioral changes, and alterations in consciousness, which may be present in delirium or dementia.

The acute management of dementia and delirium is variable and depends on the patient’s underlying medical conditions and presenting symptoms. The main goal of managing dementia and delirium in the emergency department is to identify and treat any life-threatening underlying causes. Based on the patient’s signs and symptoms, a thorough history, physical exam, and pertinent investigations should be ordered. Patient and staff safety should also be prioritized, as these patients may be aggressive and combative.

Obtaining investigations to evaluate for the underlying cause may be hindered by the patient’s aggressive and combative state. If this is the case, the first attempt is to calm the patient and de-escalate the situation verbally. If unsuccessful, chemical sedation should be considered for the safety of the patient and the healthcare staff. Examples of chemical sedation used in an emergency department setting include benzodiazepines, antipsychotics, and dexmedetomidine [17,18]. Close monitoring is necessary after the patient is sedated. Sedatives should be used only when necessary, as they have the potential to worsen delirium and disorientation.

Physical restraints and environmental seclusion are other adjunctive treatments for agitated delirium or dementia patients. However, their use should be weighed with the psychological and physical risks they may cause (e.g., emotional distress, skin and soft tissue injuries, orthopedic injuries, rhabdomyolysis, etc.). Alternative methods of managing agitation should always be attempted prior to physical restraint, such as explaining your desire to care for the patient, orienting the confused patient to his or her surroundings, using verbal de-escalation techniques, providing psychosocial support, and relocating to a calm and quiet environment, if possible [19].

Special Patient Groups

Most patients presenting with delirium and/or dementia are elderly patients. Younger patients (<60 years) presenting with delirium or patients who have rapidly progressing dementia may require extensive evaluation to discover the underlying cause. Further investigations could include lumbar puncture, electroencephalography, advanced neuroimaging, neuropsychological, and genetic testing [20]. Regardless of age, the most common causes of early-onset dementia are still Alzheimer’s disease, vascular dementia, and frontotemporal dementia [21].

When To Admit This Patient

Admission of dementia and delirious patients depends on various factors, including the severity of symptoms, comorbidities, and safety concerns. Patients who present with acute changes in their mental status, such as sudden confusion or agitation, should be further assessed for any underlying medical conditions and often require hospitalization. Delirious patients, particularly those with severe symptoms or who are at risk of harming themselves and others, should also be admitted until stabilized. Ultimately, the decision to admit dementia and delirious patients in an emergency department setting should be based on a comprehensive evaluation of the patient’s medical history, current symptoms, and risk factors.

The patient who is coming to the emergency department for a chronic presentation of Alzheimer’s dementia could be discharged if life-threatening conditions have been ruled out and home safety is not a concern. They should be referred to an outpatient primary care doctor or a geriatrician for follow-up and prescription medications to manage behavioral symptoms. Be sure to educate the patient’s family members on the diagnosis and to monitor for any new or worsening symptoms that may require urgent medical attention. Advise the family on managing certain scenarios, prioritizing the patient’s basic daily needs, addressing any medical concerns, and maintaining patient and family safety. Refer the patient to a geriatric community support program, if available.

Revisiting Your Patient

Adam’s initial vital signs are stable, and you have decided to continue his management in the consultation room. His history of cognitive and behavioral change over the past year is consistent with dementia. However, his acute presentation of impaired consciousness level and disorientation raises your suspicion of concurrent delirium from an underlying medical condition. Collateral history from the family indicates that Adam lives with his wife, who is 85 years old and limited in her ability to assist Adam with his daily needs. Focused drug and alcohol history is unrevealing.

Further neurological exams do not identify any focal neurological signs or gait disturbance. Physical examinations of the cardiovascular, respiratory, and abdomen are unremarkable. Blood glucose is within the normal range. Due to his disorientation, his Glasgow coma score is 14 (E4/V4/M6).

You consider using AMT4 to screen for cognitive impairment. He can recall his age and date of birth and tell where he is, but he fails to tell us the current year. You establish that he has delirium with impaired alertness and likely an underlying cognitive impairment.

You decide to conduct further investigation to look for potential underlying causes, especially those which may prompt immediate treatment. You arrange blood tests, including complete blood count, electrolytes, liver, and renal function tests, in consideration of potential sepsis, electrolyte disturbance, and acute organ failure. You arrange a CT brain to rule out any acute cerebral hemorrhage and space-occupying lesion. Chest X-ray and ECG are performed, as well. As you order these investigations, you consider that the patient may become agitated and uncooperative during these tests, so you review options for chemical sedation should they be needed.

You discuss openly with Adam and his family on his diagnosis of delirium and likely dementia. Your preliminary investigations show a urinary tract infection; one dose of intravenous antibiotics has been ordered. You suggest admitting Adam for monitoring and investigations due to safety concerns and his inability to care for himself due to his recent rapid decline. You discuss the importance of appropriate follow-up care and geriatric resources specializing in dementia. The patient is admitted to the general medical floor for further testing and monitoring.

Authors

Lo Lucian Simeon

Lucian Lo is a medical student at The Chinese University of Hong Kong. An avid enthusiast of emergency medicine and humanitarian work, he hopes to one day combine his two great passions as a front-line healthcare professional in conflict and disaster zones. He is a certified Advanced Medical Life Support Provider and Youth Mental Health First Aid Provider. In addition, he has led and organized multiple medical service projects in Hong Kong, Nepal, and Thailand. In regard to emergency medicine, his interests include trauma care, intensive care medicine, and pre-hospital emergency medicine.

Ngai Oona Wing Yan

Oona Ngai is a medical student at The Chinese University of Hong Kong with a passion for emergency medicine and humanitarian work. She has organized and participated in various volunteer services for vulnerable communities in Hong Kong, including the homeless, refugees, and domestic helpers. Oona is also a St. John’s certified Advanced Medical Life Support Provider and aspires to better equip herself with the necessary skills and knowledge to provide effective medical care in emergency situations. In addition, she has published a life story book on rare diseases to raise awareness and advocate for those in need.

Lo Yat Hei

Dr. Lo Yat Hei is an emergency physician who is trained and grew up in Hong Kong. He now serves at the Accident and Emergency Department of Prince of Wales Hospital and teaches at the Accident and Emergency Medicine Academic Unit of the Chinese University of Hong Kong. When not practicing medicine, he enjoys gardening, ceramics and playing mahjong.

Listen to the chapter

References

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). American Psychiatric Association; 2013.
World Health Organization. “Dementia.” Fact Sheet, https://www.who.int/news-room/fact-sheets/detail/dementia.
Ljubenkov PA, Geschwind MD. Dementia. Semin Neurol. 2016;36(4):397-404. doi:10.1055/s-0036-1585096
Plum F. The pathophysiology of dementia. Gerontology. 1986;32 Suppl 1:67-72. doi:10.1159/000212832
Wilson JE, Mart MF, Cunningham C, et al. Delirium [published correction appears in Nat Rev Dis Primers. 2020 Dec 1;6(1):94]. Nat Rev Dis Primers. 2020;6(1):90. Published 2020 Nov 12. doi:10.1038/s41572-020-00223-4
Maclullich AM, Ferguson KJ, Miller T, de Rooij SE, Cunningham C. Unravelling the pathophysiology of delirium: a focus on the role of aberrant stress responses. J Psychosom Res. 2008;65(3):229-238. doi:10.1016/j.jpsychores.2008.05.019
Fong TG, Tulebaev SR, Inouye SK. Delirium in elderly adults: diagnosis, prevention and treatment. Nat Rev Neurol. 2009;5(4):210-220. doi:10.1038/nrneurol.2009.24
Avelino-Silva TJ, Campora F, Curiati JAE, Jacob-Filho W. Prognostic effects of delirium motor subtypes in hospitalized older adults: A prospective cohort study. PloS one. 2018;13(1):e0191092. doi:10.1371/journal.pone.0191092
Emmady PD, Schoo C, Tadi P. “Major Neurocognitive Disorder (Dementia).” In: StatPearls. StatPearls Publishing; 2023. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557444/
Morandi A, Davis D, Bellelli G, et al. The Diagnosis of Delirium Superimposed on Dementia: An Emerging Challenge. J Am Med Dir Assoc. 2017;18(1):12–18. doi:10.1016/j.jamda.2016.07.014
Han JH, Suyama J. Delirium and Dementia. Clin Geriatr Med. 2018;34(3):327-354. doi:10.1016/j.cger.2018.05.001
Han JH, Wilson A, Ely EW. Delirium in the older emergency department patient: a quiet epidemic. Emerg Med Clin North Am. 2010;28(3):611-631. doi:10.1016/j.emc.2010.03.005
Brodaty H, Connors MH. Pseudodementia, pseudo-pseudodementia, and pseudodepression. Alzheimers Dement. 2020;12(1):e12027. doi:10.1002/dad2.12027
Ross GW, Bowen JD. The diagnosis and differential diagnosis of dementia. Med Clin North Am. 2002;86(3):455-476. doi:10.1016/s0025-7125(02)00009-3
Carpenter CR, Banerjee J, Keyes D, et al. Accuracy of Dementia Screening Instruments in Emergency Medicine: A Diagnostic Meta-analysis. Acad Emerg Med. 2019;26(2):226-245. doi:10.1111/acem.13573
Nasreddine ZS, Phillips NA, Bédirian V, et al. The Montreal Cognitive Assessment, MoCA: a brief screening tool for mild cognitive impairment. J Am Geriatr Soc. 2005;53(4):695–699. doi:10.1111/j.1532-5415.2005.53221.x
Barr J, Fraser GL, Puntillo K, et al. Clinical practice guidelines for the management of pain, agitation, and delirium in adult patients in the intensive care unit. Critical Care Medicine. 2013;41(1):263-306. doi: 10.1097/CCM.0b013e3182783b72
Hall JE, Uhrich TD, Barney JA, Arain SR, Ebert TJ. Sedative, amnestic, and analgesic properties of small-dose dexmedetomidine infusions. Anesth Analg. 2000;90(3):699-705. doi: 10.1097/00000539-200003000-00033
Lightfoot CB, Breden C, Moczygemba LR. Delirium: diagnosis, prevention and management. Am J Health Syst Pharm. 2017;74(18):1365-1375. doi: 10.2146/ajhp160950
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Reviewed and Edited By

Joseph Ciano, DO, MPH, MS

Dr. Ciano is a board-certified attending emergency medicine physician from New York, USA. He works in the Department of Emergency Medicine and Global Health at the Hospital of the University of Pennsylvania. Dr. Ciano’s global work focuses on capacity building and medical education and training in low-middle income countries. He is thrilled to collaborate with the iEM Education Project in creating free educational content for medical trainees and physicians.

Arif Alper Cevik, MD, FEMAT, FIFEM

The ABCDE Approach to Undifferentiated Critically Ill and Injured Patient (2024)

November 11, 2024November 11, 2024 ~ iEM Education Project Team ~ Leave a comment

by Roxanne R. Maria, Hamid A. Chatha

You have a new patient!

A 40-year-old male, a truck driver, is involved in a head-on collision with another vehicle. He has been brought in by ambulance. According to the paramedics, the vehicles were traveling at approximately 85 km/hr, and the patient was restrained by a seatbelt. On arrival at the Emergency Department (ED), the patient is agitated and mildly disoriented. He is tachypneic with a respiratory rate of 30/min, maintaining an O2 saturation of 95% on 12 L/min oxygen via a non-rebreather mask, heart rate of 128 beats/min, blood pressure of 90/52 mmHg, and temperature of 36.1°C. The patient also received 1 L of 0.9% normal saline and 1 unit of O-negative packed red cells in the ambulance. Despite this, his respiratory rate, heart rate, and level of disorientation have worsened.

Emergency Department

In the ED, patients present with a variety of clinical presentations, including both life-threatening and non-life-threatening. Some may have been seen and referred by a clinician before arrival or brought to the department after pre-hospital assessment and care by the emergency medical services (EMS) [1]. Health emergencies affect all age groups and include conditions like acute coronary syndrome, strokes, acute complications of pregnancy, or any chronic illness. Emergency health care providers should respond to these clinically ‘undifferentiated’ patients with symptoms for which the diagnosis may not be known [2]. The root cause of most life-threatening conditions in the ED may be medical or surgical, infection or trauma [2].

In the Emergency Department (ED), there are several potentially life-threatening presentations that demand immediate stabilization. These include trauma, which can result from various forms of accidents or injuries, and shortness of breath, which might indicate critical respiratory distress. An altered mental state also requires prompt attention, as it may signal underlying neurological or systemic issues. Shock, often evidenced by dangerously low blood pressure. Chest pain or discomfort, which could be indicative of a cardiac event, are other urgent concerns. Additionally, cases of poisoning, ingestion of harmful substances, or exposure to toxic materials also necessitate rapid intervention to prevent further harm. Each of these presentations is a medical priority, highlighting the importance of timely and effective response in the ED to ensure patient safety and stability.

These symptoms maybe the only picture that the patients present with, and may constitute the early stage of a critical illness requiring rapid, appropriate intervention and resuscitation, even when the patient seems to appear relatively well [2].

Emergency conditions often require immediate intervention long before a definitive diagnosis is made to stabilize the critically ill patient [3]. Thus, this chapter intends to briefly introduce a basic systematic approach to identifying and managing acute, potentially life-threatening conditions in these patients. This approach will enable all frontline providers, including students, nurses, pre-hospital technicians, and physicians, to manage these patients even in the setting of limited resources [2].

A complete assessment and management of each of the presentations mentioned above is beyond the scope of this chapter. However, the initial approach remains the same, regardless of the patient population or setting [4].

History of the ABCDE approach

The ABC mnemonic’s origins may be traced back to the 1950s. The first two letters of the mnemonic, A and B, resulted from Dr Safar’s description of airway protection techniques and administration of rescue breaths. Kouwenhoven and colleagues later added the letter C to their description of closed-chest cardiac massage [3].

Styner is credited with further developing the Airway, Breathing, Circulation, Disability, and Exposure (ABCDE) approach. After a local aircraft disaster in 1976, Styner and his family were taken to a local healthcare facility, where he saw an insufficiency in the emergency treatment offered. He then founded the Advanced Trauma Life Support course, emphasizing a methodical approach to treating severely injured patients.

The ABCDE approach is universally accepted and utilized by emergency medicine clinicians, technicians, critical care specialists, and traumatologists [3]. Thus, this approach is recommended by international guidelines for suspected serious illness or underlying injury, irrespective of the diagnosis [5]. It is also the first step in post-resuscitation care after the patient achieves return of spontaneous circulation (ROSC) from a cardiac arrest [3]. This systematic approach also aims to improve coordination among the team members and saves time to make critical decisions [3].

The ABCDE approach

Since time is of the essence, the ABCDE method is a systematic approach that can be easily and quickly practiced in the ED. This is incorporated into what is known as ‘Initial patient assessment,’ one of the most crucial steps in evaluation [6]. At each step of this approach, life-threatening problems must be addressed before proceeding to the next assessment step. After the initial assessment, patients must be reassessed regularly to evaluate the treatment response. Anticipate and call for extra help early [7]. Appropriate role allocation and good communication are important for effective team working [7]. Once the patient is stabilized, a secondary survey should be conducted, which includes a thorough history, physical examination, and diagnostic testing [8]. Finally, the tertiary survey is done within 24 hours of presentation to identify any other missed injuries in trauma. Once it is recognized that the patient’s needs exceed the facility’s capabilities, the transfer process must be initiated to an appropriately specialized care center accordingly [8].

Ensure Safe Environment

Before initiating the ABCDE approach, it is essential to ensure both personal safety and a secure environment. This preparation includes addressing any potential risks, such as unexpected or violent behavior, environmental hazards, and the risk of exposure to communicable diseases. Health professionals should consider using appropriate personal protective equipment (PPE) suited to the situation, which may include gloves, gowns, masks, goggles, and thorough hand washing. These precautions are vital to protect both the healthcare provider and the patient, ensuring a safe environment for medical intervention [4].

Initiate First Response

The Resuscitation Council UK (RCUK) (2015) recommends performing a range of initial activities before proceeding with the ABCDE approach [4].

Examine the patient in general (skin color, posture, sensorium, etc.) to determine whether they seem critically ill [4].

After introducing yourself, an initial assessment can be completed in the first 10-15 seconds by asking patients their names and about their active complaints. If they respond normally, it means the airway is patent and brain perfusion is expected [9]. Check for breathing and pulse if the patient appears unconscious or has collapsed. If there is no pulse, call for help and immediately start cardiopulmonary resuscitation (CPR), adhering to local guidelines [9].

Detailed ABCDE Evaluation

Primary Survey

Patients are assessed and prioritized according to their presentations and vital signs. In primary survey, critically ill patients are managed efficiently along with resuscitation. The approach represents the sequence of steps as described below [10]:

A – Airway (with C spine control in Trauma patients)

B – Breathing and Ventilation

C – Circulation (With Hemorrhage control in active bleeding)

D – Disability

E – Exposure / Environment control

A – Airway

Airway obstruction is critical! Gain expert help immediately. If not treated, it can lead to hypoxia, causing damage to the brain, kidneys, and heart, resulting in cardiac arrest and death [4].

Airway management remains the cornerstone of resuscitation and is a specialized skill for the emergency clinician [9].

Assessment of airway patency is the first step. Can the patient talk? If yes, then the airway is patent and not in immediate danger. If not, look for the signs of airway compromise: Noisy breathing, inability to speak, presence of added sounds, stridor or wheezing, choking or gagging, cyanosis, and use of accessory muscles.

The next step is to open the mouth and look for anything obstructing the airway, such as secretions, blood, a foreign body, or mandibular/tracheal/laryngeal fractures [10].

While examining and managing the airway, great care must be taken to restrict excessive movement of the cervical spine and assume the existence of a spinal injury in cases of trauma [11].

Several critical factors can compromise a patient’s airway and must be addressed promptly in emergency settings. A depressed level of consciousness, which may result from conditions such as opioid overdose, head injury, or stroke, can impair airway protection and lead to significant risk [10]. Additionally, an inhaled foreign body, or the presence of blood, vomit, or other secretions, can obstruct the airway and necessitate immediate intervention. Fractures of the facial bones or mandible further complicate airway management due to potential structural damage. Soft tissue swelling, whether caused by anaphylaxis (angioedema) or severe infections like quinsy or necrotizing fasciitis, also seriously threatens the airway. These conditions highlight the importance of vigilant monitoring and rapid response to maintain airway patency and prevent complications.

Intervention: Several basic maneuvers can help maintain a clear airway. Suctioning should be performed if there are any secretions or blood present. Additionally, using the head-tilt, chin-lift, and jaw-thrust maneuvers can aid in keeping the airway open. For patients with a low Glasgow Coma Scale (GCS) score, placing an oropharyngeal or nasopharyngeal airway can be beneficial in maintaining airway patency. It’s also important to inspect the airway for any obvious obstructions; if a visible object is within reach, it may be removed carefully using a finger sweep or suction. It is crucial to remember that assistance from an anesthetist may be required in some cases.

In trauma patients, to protect the C-spine, perform a jaw-thrust rather than a head-tilt chin-lift maneuver and immobilize the C-spine with a cervical collar [9].

A definitive airway, such as endotracheal intubation, may be necessary in patients with airway obstruction, GCS ≤ 8, severe shock or cardiac arrest, and at risk of inhalation injuries [8].

If intubation has failed or is contraindicated, a definitive airway must be established surgically [11].

B – Breathing and Ventilation

Effective ventilation relies on the proper functioning of the lungs, chest wall, and diaphragm, along with a patent airway and sufficient gas exchange to optimize oxygenation [10]. To assess breathing and ventilation, clinicians should evaluate oxygen saturation, monitor the respiratory rate for any signs of abnormality—such as rapid breathing (tachypnea), slow breathing (bradypnea), or shallow breathing (Kussmaul breathing)—and observe for increased work of breathing, such as accessory muscle use, chest retractions, or nasal flaring. Other critical assessments include checking for neck vein distention, examining the position of the trachea, chest expansion, and any injuries or tenderness, as well as auscultating for bilateral air entry and any additional sounds. Chest percussion should be performed to identify dullness, which may indicate hemothorax or effusion, or hyperresonance, suggestive of pneumothorax. Certain pathologies, like tension pneumothorax, massive hemothorax, open pneumothorax, and tracheal or bronchial injuries, can rapidly disrupt ventilation. Other conditions, including simple pneumothorax, pleural effusion, simple hemothorax, rib fractures, flail chest, and pulmonary contusion, may compromise ventilation to a lesser degree [10].

Interventions:

Oxygen – Ensure all patients are adequately oxygenated, with supplemental oxygen delivered to all severely injured trauma patients [11]. Place them on well-fitted oxygen reservoir masks with a flow rate > 10 L/min, which can then be titrated as needed to maintain adequate saturations. Other means of oxygen delivery (nasal catheter, nasal cannula, non-rebreather) can also be used.
Bag mask valve ventilation with oxygen – should be given to unconscious patients with abnormal breathing patterns (slow or shallow respiration).
Other interventions include salbutamol nebulizers, epinephrine, steroids, needle decompression, chest tube insertion, and the use of noninvasive ventilation and pressure support in different clinical scenarios.

C – Circulation (With Hemorrhage control in active bleeding)

Major circulatory compromise in critically ill patients can result from either blood volume loss or reduced cardiac output. In trauma cases, hypotension is assumed to be due to blood loss until proven otherwise. To assess the hemodynamic status, several key evaluations should be performed. These include checking the level of consciousness, as an altered state may indicate impaired cerebral perfusion, and assessing skin perfusion for signs like pallor, cyanosis, mottling, or flushing. Vital signs such as heart rate and blood pressure should be monitored for abnormalities like tachycardia, bradycardia, hypotension, or hypertension. Auscultation can reveal muffled heart sounds, which may suggest cardiac tamponade or pneumothorax, as well as murmurs or a pericardial friction rub that could indicate pericarditis. Checking the extremities for capillary refill and skin temperature is also essential. Additionally, palpation of the abdomen for tenderness or a pulsatile mass may reveal an abdominal aortic aneurysm, while peripheral edema, such as pedal edema, might indicate heart failure.

Interventions:

Two large-bore IV cannulations must be placed. If this attempt fails, intraosseous access is necessary. Hemorrhagic shock—A definitive control of bleeding along with replacement of intravascular volume is essential. Initial resuscitation should start with warm crystalloids, and blood products should be used. Massive Transfusion Protocol (MTP) should be activated according to local guidelines. In hemorrhagic shock, vasopressors and reversal of anticoagulation (if required) can be considered.
Hemorrhage control: External hemorrhage can be controlled by direct manual pressure over the site of the wound or tourniquet application.
In the case of pelvic or femur fractures, placement of pelvic binders or extremity splints may help to stabilize, although definitive management may be surgical or interventional radiological procedures.
Obstructive shock – Immediate pericardiocentesis for cardiac tamponade, chest tube insertion for tension pneumothorax, and thrombolysis for massive pulmonary embolism.
Distributive shock – intramuscular epinephrine for anaphylactic shock, empiric antibiotics for sepsis, and hydrocortisone for adrenal crisis.
Appropriate antihypertensives in hypertensive emergency.

D – Disability

Evaluate neurological status either with AVPU (Alert, Verbal, Pain and Unresponsive) [5] or GCS (Glasgow Coma Scale).

Evaluate for agitation, head and neck trauma, focal neurological signs (seizure, hemiplegia, etc), lateralizing signs, meningeal signs, signs of raised intracranial pressure, and pupillary examination (size and symmetry). Identify any classic toxidromes (sympathomimetic, cholinergic, anticholinergic, opioid, serotonergic, and sedative-hypnotic toxidromes).

Choose the best response of patient
EYE OPENING
4: Spontaneously
3: To verbal command
2: To pain
1: No response

BEST VERBAL RESPONSE
5: Oriented and converses
4: Disoriented and converses
3: Inappropriate words; cries
2: Incomprehensible sounds
1: No response

BEST MOTOR RESPONSE
6: Obeys command
5: Localizes pain
4: Flexion withdrawal
3: Flexion abnormal (decorticate)
2: Extension (decerebrate)
1: No response

Glasgow Coma Score (GCS) (Modified from Teasdale, G., & Jennett, B. (1974). Assessment of coma and impaired consciousness: a practical scale. The Lancet, 304(7872), 81-84.) - Please read this article to get more insight regarding GCS.

The Glasgow Coma Scale (GCS) is a critical tool for assessing the level of consciousness in critically ill patients, providing a score based on eye, verbal, and motor responses. A GCS score ranges from 3 to 15, with lower scores indicating more severe impairment. Scores of 13-15 generally indicate mild impairment, 9-12 suggest moderate impairment, and scores of 8 or below (comatose patient) represent severe impairment and a high risk of poor outcomes. In critically ill patients, a declining GCS score can signal worsening neurological status, potentially due to factors like traumatic brain injury, hypoxia, or systemic deterioration, and often warrants immediate intervention to address underlying causes.

E – Exposure and Environmental control

It is necessary to expose the patient appropriately whilst maintaining dignity and body temperature.

Look at the skin for any signs of trauma (burns, stab wounds, gunshot wounds, etc.), rashes, infected wounds, ulcers, needle track marks, medication patches, implantable devices, tubes, catheters, and stomas; measure core body temperature, and perform logroll (trauma).

Do not forget to check frequently concealed and overlooked areas such as the genital, inguinal, perineal, axilla, back and under dressings [8].

Interventions:

Use specialized personal protective equipment (PPE), remove all possible triggers such as wet or contaminated clothing, and maintain core body temperature.
Minimize hypothermia (external rewarming, warm IV fluids) and hyperthermia (surface cooling, cold IV fluids, antipyretics for fever).

Adjuncts to primary survey

1. Electrocardiography (ECG)
2. Pulse oximetry
3. Carbon dioxide (CO2) monitoring
4. Arterial blood gas (ABG) analysis
5. Urinary catheterization (to assess for hematuria and urine output)
6. Gastric catheterization (for decompression)
7. Blood lactate level measurement
8. Chest and pelvis X-rays
9. Extended focused assessment with sonography for trauma (eFAST)

These adjuncts help provide a comprehensive evaluation of the patient’s condition [10].

Secondary Survey

After the initial primary survey and stabilization, proceed to the secondary survey. This includes a detailed history (SAMPLE)and a head-to-toe examination, including reassessment of vital signs, as there is a potential for missing an injury or other findings in an unresponsive patient [10].

The SAMPLE mnemonic is a structured approach for gathering essential patient history in emergency settings. It stands for Signs and Symptoms, Allergies, Medications, Past Medical History, Last Oral Intake, and Events leading to the illness or injury [5].

“Signs and Symptoms” involves asking the patient, family, or other witnesses about any observable signs or reported symptoms.
“Allergies” are crucial to identify to prevent harm and may help recognize conditions like anaphylaxis.
“Medications” requires a comprehensive list of all current and recent medications, including any changes in dosage.
“Past Medical History” provides insights into underlying health conditions that may influence the current illness.
“Last Oral Intake” is important for assessing risks of aspiration or complications if the patient requires sedation or surgery.
Finally, understanding the “Events” surrounding the illness or injury aids in determining its cause and severity.

Together, these components guide healthcare providers in developing a more accurate and effective treatment plan.

In the secondary survey, a thorough approach is taken to ensure comprehensive care for the patient. This includes performing relevant and appropriate diagnostic tests based on the clinical assessment to confirm diagnoses and guide further treatment. Critical, targeted treatments should be initiated promptly, along with adequate supportive care to stabilize the patient’s condition. If necessary, specialized consults are obtained to address specific medical needs. Additionally, the healthcare team must assess the need for escalation of care or consider an interfacility transfer if the patient requires more specialized resources or advanced care options [8]. This structured approach ensures that all aspects of the patient’s condition are managed effectively.

Adjuncts to secondary survey

Additional x-rays for the spine and extremities, CT scans of the head, chest, abdomen, and spine, urography and angiography with contrast, transesophageal ultrasound, bronchoscopy, and other diagnostics [10].

If the patient starts to deteriorate, immediately go back to the ABCDE approach and reassess!

Special Patient Groups

In recent ATLS updates, the ABCDE approach has been modified to the xABCDEF approach, where “x” stands for eXsanguinating eXternal hemorrhage control and “F” stands for further factors such as special groups (pediatric, Geriatric, and Pregnancy). While the xABCDEF approach is universal and applies to all patient groups, specific anatomic and physiological differences in different populations should be considered while evaluating and treating life-threatening conditions. Some special population groups are discussed here:

Pediatrics [10]

Children have smaller body mass but higher body surface area than their body mass and proportionately larger heads than adults. These characteristics cause children to have increased energy transfer, hypothermia, and blunt brain trauma.

A useful adjunct is the Broselow® Pediatric Emergency Tape, which helps to rapidly identify weight-based medication doses, fluid volumes, and equipment sizes.

The ABCDE approach in children should proceed in the same manner as in adults, bearing in mind the anatomical differences.

Airway – Various anatomical features in children, such as large tissues of the oropharynx (tongue, tonsils), funnel-shaped larynx, more cephalad and anteriorly placed larynx and vocal cords, and shorter length of the trachea, make assessment and management of the airway difficult. Additionally, in smaller children, there is disproportionality in size between the cranium and the midface, making the large occiput in passive flexion of the cervical spine, resulting in the posterior pharynx being displaced anteriorly. The neutral alignment of the spine can be achieved by placing a 1-inch pad below the entire torso of the infant or toddler.

The most preferred technique for orotracheal intubation is under direct vision, along with restriction of the cervical spine, to achieve a definitive airway.

Infants are more prone to bradycardia due to laryngeal stimulation during intubation than older children and adults. Hence, when drug-assisted intubation is required, the administration of atropine sulfate pretreatment must be considered. Atropine also helps to dry out oral secretions, further enhancing the view of landmarks for intubation.

When the airway cannot be maintained by bag-mask ventilation or orotracheal intubation, a rescue airway with either a laryngeal mask airway (LMA), an intubating LMA, or a needle cricothyroidotomy is required.

Red flag signs in children include stridor, excessive drooling, airway swelling, and the child’s unwillingness to move the neck. Examine the airway carefully for any foreign bodies, burns, or obstruction.

Breathing and ventilation – Children’s respiratory rates decrease with age. The normal tidal volumes in infants and children vary from 4-6 ml/kg to 6-8 ml/kg while assisting in ventilation. Care must be taken to limit pressure-related barotrauma during ventilation. It is recommended that children weighing less than 30 kg use a pediatric bag valve mask.

Injuries such as pneumothorax, hemothorax, and hemopneumothorax should be treated by pleural decompression, for tension pneumothorax, and needle decompression in the 2nd intercostal space (over the top of the third rib) at the midclavicular line. The site for chest tube insertion remains the same as in adults.

The most common cause of pediatric cardiac arrest is hypoxia, and the most common acid-base abnormality encountered is respiratory acidosis due to hypoventilation.

Circulation – Important factors in assessing and managing circulation and shock are looking for signs of circulatory compromise, ascertaining the patient’s weight and circulatory volume, gaining timely peripheral venous access, delivering an appropriate volume of fluids with or without blood replacement, evaluating the adequacy of resuscitation, and aiming for thermoregulation.

Children have increased physiological reserves. A 30% decrease in the circulating blood volume may be required for a fall in the systolic blood pressure. Hence, it is important to look for other subtle signs of blood loss, such as progressive weakening of peripheral pulses, narrow pulse pressure to less than 20 mm Hg, skin mottling (in infants and young children), cool extremities, and decreased level of consciousness.

The preferred route is peripheral venous access, but if this is unsuccessful after two attempts, intraosseous access should be obtained.

Fluid resuscitation must be commenced at 20 ml/kg boluses of isotonic crystalloids. If the patient has ongoing bleeding, packed red blood cells may be initiated at 10 ml/kg as soon as possible. Given that children have increased metabolic rates, thinner skin, and lack of substantial subcutaneous tissue, they are prone to develop hypothermia quickly, which may impede a child’s response to treatment, increase coagulation times, and affect the central nervous system (CNS) function. Therefore, overhead lamps, thermal blankets, as well as administration of warm IV fluids, blood products, and inhaled gases may be required during the initial phase of evaluation and resuscitation.

Disability – Hypoglycemia is a very common cause of altered mental state in children, and children can present with altered mental state or seizures. Check for blood glucose in children; if low, administer glucose (IV D10 or D25).

Geriatric [10]

In cases of trauma in geriatric patients, physiological events that may have led to it (e.g., cardiac dysrhythmias) must be considered. A detailed review of long-term medical conditions and medications, along with their effect on vital signs, is necessary. Risk factors for falls include physical impairments, long-term medication use, dementia, and visual, cognitive, or neurological impairments.

Elderly patients are more prone to sustaining burn injuries due to decreased reaction times, hearing and visual impairment, and inability to escape the burning structure. Burn injury remains the cause of significant mortality.

Airway – Due to loss of protective airway reflexes, airway management in the elderly can be challenging and requires a timely decision to establish a life-saving definitive airway. Opening of the mouth and cervical spine maneuvering may be challenging with arthritic changes. Loose dentures should be removed, while well-fitted dentures should be better left inside. Some patients may be edentulous, making intubation easier, but bag-mask ventilation is difficult.

While performing rapid sequence intubation, it is recommended to lower the doses of barbiturates, benzodiazepine, and other sedatives to 20% to 40% to avoid the risk of cardiovascular depression.

Breathing – Elderly patients have decreased compliance of the lungs and the chest wall, which leads to increased breathing work, placing them at a higher risk for respiratory failure. Aging also results in suppressed heart rate during hypoxia, and respiratory failure may present alongside.

Circulation – These patients may have increasing systemic vascular resistance in response to hypovolemia, given that they may have a fixed heart rate and cardiac output. Also, an acceptable blood pressure reading may truly indicate a hypotensive state, as most elderly patients have preexisting hypertension.

A systolic blood pressure of 110 mm Hg is used as a threshold for identifying hypotension in adults over 65.

Several variables, namely base deficit, serum lactate, shock index, and tissue-specific lab markers, can be used to assess for hypoperfusion. Consider early use of advanced monitoring of fluid status, such as central venous pressure (CVP), echocardiography, and bedside ultrasonography, to guide resuscitation.

Disability – Traumatic brain injury is one of the significant complications among the elderly. The dura becomes more adherent to the skull with age, which increases the risk of epidural hematoma. Moreover, these patients are commonly prescribed anticoagulant and antiplatelet medications, which puts these individuals at a higher risk of developing intracranial hemorrhage. Therefore, a very low threshold is indicated for further CT scan imaging in ruling out acute intracranial and spinal pathologies.

Exposure – Increased risk of hypothermia due to loss of subcutaneous fat, nutritional deficiencies, chronic medical illnesses, and therapies. Complications of immobility, such as pressure injuries and delirium, may develop.

Rapid evaluation and relieving from spine boards and cervical collars will help to reduce these injuries.

Pregnant [10]

Evaluation and management of pregnant individuals can be challenging due to the physiological and anatomical changes that affect nearly every organ system in the body. Therefore, knowledge of the physiological and anatomical changes during pregnancy regarding the mother and the fetus is important to provide the best and most appropriate resuscitation and care for both.

The best initial treatment for the fetus is by providing optimal resuscitation of the mother.

Female patients in the reproductive age who present to the ED must be considered pregnant until proven by a definitive pregnancy test or ultrasound exam.

A specialized obstetrician and surgeon should be consulted early in the assessment of pregnant trauma patients; if not available, early transfer to an appropriate facility should be sought.

The uterus is an intrapelvic organ until the 12th week of gestation, around 34 to 36 weeks when it rises to the level of the costal margin. This makes the uterus and its contents more susceptible to blunt abdominal trauma, whereas the bowel remains somewhat preserved. Nevertheless, penetrating upper abdominal trauma in the late gestational period can cause complex intestinal injury due to displacement.

Amniotic fluid embolism and disseminated intravascular coagulation are significant complications of trauma in pregnancy. In the vertex presentation, the fetal head lies in the pelvis, and any fracture of the pelvis can result in fetal skull fracture or intracranial injury.

A sudden decrease in maternal intravascular volume can lead to a profound increase in uterine vascular resistance, thus reducing fetal oxygenation regardless of normal maternal vital signs.

The volume of plasma increases throughout pregnancy and peaks by 34 weeks of gestation. Physiological anemia of pregnancy occurs when there is an increase in red blood cell (RBC) volume, leading to decreased hematocrit levels. In normal, healthy pregnant individuals, blood loss of 1200 to 1500 ml can occur without showing any signs or symptoms of hypovolemia. Nonetheless, this compromise may be seen as fetal distress, indicated by an abnormal fetal heart rate on monitoring.

Leukocytosis is expected during pregnancy, peaking up to 25,000/mm3 during labor. Serum fibrinogen and other clotting factors may be mildly increased, with shorter prothrombin and partial thromboplastin times. However, bleeding and clotting times remain the same.

During late pregnancy, in a supine position, vena cava compression can cause a decrease in cardiac output by 30 % due to lesser venous return from the lower extremities.

In the third trimester of pregnancy, heart rate increases up to 10-15 beats/min than the baseline while assessing for tachycardia in response to hypovolemia. Hypertension, along with proteinuria, indicates the need to manage preeclampsia. Be mindful of eclampsia as a complication during late pregnancy, as its presentation can be similar to a head injury (seizures with hypertension, hyperreflexia, proteinuria, and peripheral edema)

An increase in the tidal volume causes increases in the minute ventilation and hypocapnia (PaCO2 of 30 mm Hg), which is common in the later gestational period. Therefore,

Maintaining adequate arterial oxygenation during resuscitation as oxygen consumption increases during pregnancy is also important.

By the seventh month of gestation, the symphysis pubis widens to about 4 to 8 mm, and sacroiliac joint spaces increase. These alterations must be kept in mind while evaluating pelvic X-ray films during trauma. Additionally, the pelvic vessels that surround the gravid uterus can become engorged, leading to large retroperitoneal hemorrhage after blunt trauma with pelvic fractures.

Every pregnant patient who has sustained major trauma must be admitted with appropriate obstetric and trauma facilities.

Pregnant individuals may present to the ED with non-obstetric causes such as intentional (intimate partner violence, suicide attempt) and unintentional trauma (MVC, fall), and obstetric causes such as ectopic pregnancy, vaginal bleed, contractions, abdominal pain, decreased fetal movement, etc.

“To optimize outcomes for the mother and fetus, assessment and resuscitation of the mother is performed first and then the fetus, before proceeding for secondary survey of the mother.”

Primary Survey - Mother

Airway – Ensure the patient has a patent and maintainable airway with adequate ventilation. In cases where intubation is necessary, maintain appropriate PaCO2 levels according to the patient’s gestational age. Due to the superior displacement of abdominal organs and delayed gastric emptying, there is an increased risk of aspiration during intubation.

Breathing – These patients may have an increased rate of respiration due to pressure effects or hormonal changes. Pulse oximetry and arterial gas must be monitored as adjuncts. It must be remembered that normal maternal bicarbonate levels will be low to compensate for the respiratory alkalosis.

Circulation – Attempt to manually reposition the uterus towards the left side to relieve the pressure on the inferior vena cava and improve the venous return.

Since pregnant individuals have increased intravascular volumes, they can lose a large amount of blood before the onset of tachycardia, hypotension, or other signs of hypovolemia. Therefore, it is essential to remember that the fetus and the placenta are deprived of perfusion, leading to fetal distress while the maternal conditions appear stable.

Administer crystalloid IV fluids and type-specific blood. Vasopressors must be used only as a last resort to raise maternal blood pressure, as these agents can further cause a reduction of the uterine blood flow, leading to fetal hypoxia.

Primary Survey - Fetus

Leading causes of fetal demise include maternal shock and death, followed by placental abruption.

Assess for signs of abruptio placentae (vaginal bleeding, uterine tenderness, frequent uterine contractions, uterine tetany, and irritability). Another rare injury is the uterine rupture (abdominal tenderness, rigidity, guarding or rebound tenderness, abnormal fetal lie, etc.) accompanying hypovolemia and shock.

By 10 weeks of gestation, fetal heart tones can be assessed by Doppler ultrasound, and beyond 20-24 weeks of gestation, continuous fetal monitoring with a tocodynamometer must be performed. At least 6 hours of continuous monitoring in patients with no risk factors for fetal death is recommended, and 24 hours of monitoring in patients with a high risk of fetal death.

Secondary Survey

Perform the secondary survey for non-pregnant individuals, as mentioned.

An obstetrician should ideally examine the perineum, including the pelvis. The presence of amniotic fluid in the vagina, PH greater than 4.5, indicates chorioamniotic membrane rupture.

All pregnant patients with vaginal bleeding, uterine irritability, abdominal tenderness and pain, signs and symptoms of shock, fetal distress, and leakage of amniotic fluid should be admitted for further care.

All pregnant trauma patients with Rh-negative blood group must receive Rh immunoglobulin therapy unless the injury is remote from the uterus within 72 hours of injury.

Obese Patients [10]

In the setting of trauma, procedures such as intubation can be challenging and dangerous due to their anatomy. Diagnostic investigations such as E-FAST, DPL, and CT scans may also be challenging. Moreover, most of these patients have underlying cardiopulmonary diseases, which hinders their ability to compensate for the stress and injury.

Athletes [10]

Owing to their prime conditioning, they may not exhibit early signs such as tachycardia or tachypnea in shock cases. Additionally, they usually have low systolic and diastolic blood pressure.

Revisiting Your Patient

Let’s get back to the patient we discussed earlier and start assessing him:

Airway – The patient maintains his airway but finds breathing hard. Intervention: Apply 15L Oxygen via a nonrebreather mask.

Breathing—A strap mark contusion is seen with multiple bruises. His chest expansion is asymmetrical, with reduced breath sounds on the right side of his chest. There is a dull percussion note on the right lower half of his chest. He maintains oxygen saturation. Intervention: Prepare for chest tube insertion on the right side.

Circulation – Heart sounds are muffled with marked engorgement of the external jugular veins in the neck, a good pulse still palpable in his left radial, but cold clammy extremities. His pulse is 128/min, and his blood pressure is 92/50 mm Hg. Bedside ultrasound FAST (Focused Assessment Sonography in Trauma) shows a pericardial tamponade. Intervention: IV access was gained with two large-bore IV cannulas, blood was drawn for labs, the massive transfusion protocol for blood products was activated, a Foley catheter was inserted to monitor urinary output, and the surgery team was on board to plan for emergent pericardiocentesis.

Disability – Patient’s GCS remains 15, unremarkable pupillary examination and POC glucose is 7 mmol/dl.

Exposure – you notice the strap mark on his chest secondary to his seatbelt restraint, and the multiple bruises. The remaining evaluation is unremarkable, with no head, spine, abdomen, or limb injury.

Adjunct investigations – A portable chest x-ray shows increased cardiac shadow and multiple bilateral rib fractures. There is opacification in the right lung [12].

Discussion

This patient sustained a blunt trauma leading to pericardial tamponade and right-sided hemothorax, leading to hypovolemic shock. The most common cause of shock in a trauma patient is hypovolemic shock due to hemorrhage. However, other types of shock like cardiogenic shock (due to myocardial dysfunction), neurogenic shock (due to sympathetic dysfunction), or obstructive shock (due to tension pneumothorax, obstruction of great vessels) can occur.

Early signs of shock include tachycardia, which is the body’s attempt to preserve cardiac output and cool peripheries, and reduced capillary refill time caused by peripheral vasoconstriction. This is caused by the release of catecholamine and vasoactive hormone, which leads to increased diastolic blood pressure and reduced pulse pressure. For this reason, measuring pulse pressure rather than systolic blood pressure allows earlier detection of hypovolaemic shock, as the body can lose up to 30% of its blood volume before a drop in systolic blood pressure is appreciated.

Initiate fluid resuscitation in these patients and do not wait for them to develop hypotension.
The main aim is to maintain organ perfusion and tissue oxygenation. In children, start with crystalloid fluid boluses of 20 ml/kg, and in adults, an initial 1 L can be given. In patients who have sustained a major blood loss, consider initiating the Massive Transfusion Protocol (MTP) for blood products as soon as possible.

A few current trauma guidelines have recommended ‘permissive hypotension’ or ‘balanced resuscitation,’ where the principle is to stabilize any blood clots that may have been formed, and aggressive blood pressure resuscitation may disrupt this ‘first formed clot’ and may contribute to further hemorrhage.

To evaluate response to fluid resuscitation, assess the level of consciousness, improvement in tachycardia, skin temperature, capillary refill, and urine output (>0.5 ml/kg/hour in adults).
Besides administering packed red blood cells, do not forget to transfuse platelets, fresh frozen plasma, or cryoprecipitate, as large blood loss can develop coagulopathy in 30% of these injured patients. Tranexamic acid (TXA), an antifibrinolytic, can be utilized in addition as a 1 g bolus over 10 minutes followed by 1 g over 8 hours within 3 hours of trauma without an increased risk of thromboembolic events [11].

This systematic approach focuses on identifying and treating this hemorrhagic shock case. Bedside adjuncts such as FAST examination and portable chest X-ray can provide valuable clues to the cause of shock. A trauma CT scan is only performed once the patient is stable enough to go to the scan room.

This patient’s vital signs improve slightly but remain unstable, and blood is kept draining into the chest drain. The patient is taken to the operation theatre for an emergency thoracotomy [12].

Authors

Roxanne R. Maria

Hamid A. Chatha

Listen to the chapter

References

Initial Assessment of Emergency Department patients, The Royal College of Emergency Medicine, Feb 2017
World Health Organization. BASIC EMERGENCY CARE : Approach to the Acutely Ill and Injured.World Health Organization; 2018.
Thim T. Initial assessment and treatment with the airway, breathing, circulation, disability, exposure (ABCDE) approach. International Journal of General Medicine. 2012;5(5):117-121. doi:https://doi.org/10.2147/IJGM.S28478
Peate I, Brent D. Using the ABCDE Approach for All Critically Unwell Patients. British Journal of Healthcare Assistants. 2021;15(2):84-89. doi:https://doi.org/10.12968/bjha.2021.15.2.84
Schoeber NHC, Linders M, Binkhorst M, et al. Healthcare professionals’ knowledge of the systematic ABCDE approach: a cross-sectional study. BMC Emergency Medicine. 2022;22(1). doi:https://doi.org/10.1186/s12873-022-00753-y
Learning Objectives. https://www.moh.gov.bt/wp-content/uploads/moh-files/2017/10/Chapter-2-Emergency-Patient-Assessment.pdf
Resuscitation Council UK. The ABCDE Approach. Resuscitation Council UK. Published 2021. https://www.resus.org.uk/library/abcde-approach#:~:text=Use%20the%20Airway%2C%20Breathing%2C%20Circulation
Management of trauma patients – Knowledge @ AMBOSS. http://www.amboss.com. https://www.amboss.com/us/knowledge/Management_of_trauma_patients/
Oxford Medical Education. ABCDE assessment. Oxford Medical Education. Published 2016. https://oxfordmedicaleducation.com/emergency-medicine/abcde-assessment/
HENRY SM. ATLS Advanced Trauma Life Support 10th Edition Student Course Manual, 10e. 10th ed. AMERICAN COLLEGE OFSURGEO; 2018.
Walls RM, Hockberger RS, Gausche-Hill M, Erickson TB, Wilcox SR. Rosen’s Emergency Medicine : Concepts and Clinical Practice. Elsevier; 2.
Eamon Shamil, Ravi P, Mistry D. 100 Cases in Emergency Medicine and Critical Care. CRC Press; 2018.

Reviewed By

Arif Alper Cevik, MD, FEMAT, FIFEM

Fundamentals of ACLS (2024)

November 4, 2024November 5, 2024 ~ iEM Education Project Team ~ Leave a comment

by Mohammad Anzal Rehman

You have a new patient!

A 56-year-old man presents to the Emergency Department with complaints of chest pain and dizziness that began an hour ago. Upon assessment by the triage nurse, his vital signs are as follows: his heart rate is 107 beats per minute, and his respiratory rate is 22 breaths per minute. His blood pressure is 96/70 mmHg, and his oxygen saturation is at 90% on room air. His temperature is 36.8°C.

You are the student on shift when this patient arrives, and immediately, your mind begins to jump across differential diagnoses for this patient. As you rush toward the patient’s room to join your senior, you prepare to list out all the potential causes of chest pain proudly. This must be a Myocardial Infarction, or maybe even an Aortic Dissection. Perhaps it is that rare Boerhaave syndrome you read about last night!

You finally catch up to the Emergency Physician, but before you can open your mouth to wax lyrical about esophageal ruptures, the Doctor states “Let’s begin by evaluating the ABCs.”

Initial Assessment

Emergency Medicine is one of the few specialties in medicine where patient evaluation begins in the same way for every patient, regardless of the probable diagnosis. Most clinicians are wired to jump straight to the ‘mystery-solving’ component of clinical presentation, with many undergraduate curriculums based around disease recognition. Emergency Medicine, however, places an emphasis on systematic assessment of the patient, starting with ‘The Primary Survey’.

The Primary Survey – ABCDE Approach

The Primary Survey aims to identify life-threatening conditions rapidly and systematically in critically ill patients, with appropriate stabilizing interventions performed when an abnormality is recognized. Besides streamlining the process in a high-stakes and often chaotic environment, the alphabetical order is designed first to address the most severe causes of mortality [1].

Airway

A patient’s airway connects air, and therefore oxygen, from outside the body to the lungs. Airway management is a term used to evaluate and optimize the passage of oxygen in the upper airway, which may be impaired when there is a blockage or narrowing of this pathway. The most common cause of upper airway obstruction is the tongue, which may ‘close’ the oropharynx posteriorly in patients who are comatose or in cardiopulmonary arrest, for example.

Assessment of the airway typically starts by evaluating any external features that may impact the passage of air through the naso- and oro-pharynx, such as facial or neck trauma, fractures, deformities, and any masses or swelling that may disrupt the airway tract. Allergies, especially anaphylaxis, and significant burns may cause edema of the laryngeal airway and produce obstruction. Excessive secretions may also congest the oropharynx and produce airway obstruction.

A patent or ‘normal’ airway allows a responsive patient to speak in full sentences without difficulty, implying a non-obstructed air passage down the oropharynx and through the vocal cords.

Clinical signs of obstruction may include stridor, gurgling, drooling, choking, gagging, or apnea. A physician may also identify an impending airway obstruction where loss of gag reflex, intractable vomiting, or worsening laryngeal edema may inevitably compromise the passage of air to the lungs and produce a failure to oxygenate or ventilate, prompting a decision to secure the tract through intubation.

Management

In the responsive patient, allow for the patient to be seated or lying in their most comfortable position as you assess the patency of the airway.

‘Opening’ the airway involves positioning the patient’s head in the ‘sniffing position’. In this position, a slight extension of the head with flexion of the neck, keeping the external auditory meatus in line with or above the sternal notch, is used to optimally align the pharyngeal and laryngeal airway segments, preventing obstruction posteriorly by the tongue (Figure 1). This is useful in patients who are unresponsive and cannot consciously protect their airway.

Two maneuvers are helpful in opening an unresponsive or sedated patient’s airway, optimizing air entry to the lungs:

1. Head tilt chin lift (Figure 2A) – Using fingertips under the chin, lift the mandible anteriorly while simultaneously tilting the head back using the other hand. Do not use this if cervical spine injury is suspected!

2. Jaw thrust (Figure 2B) – With thenar eminences of both hands anchored over both maxillary regions of the patient’s face, use your fingers at both angles of the mandible to lift it anteriorly. This maneuver is preferable in cases of suspected cervical spine injury as it does not cause hyperextension of the neck.

In unresponsive patients with excessive secretions, use of a rigid suction device can clear fluid and particulate matter such as vomitus.

Intubation may be performed if airway assessment deems it necessary to protect or secure the airway tract in a definitive way. If intubation is required, it should be performed as early as possible to prevent the evolution of a difficult airway, which would lower the chances of a successful intubation. It may also be useful to establish the risk of an inherently difficult airway using the L-E-M-O-N airway assessment method as below:

Look externally – facial trauma, large incisors and/or tongue, hairy beard, or moustache

Evaluate the 3-3-2 rule – where optimal distance between incisors on mouth opening should be 3 finger breadths. Similarly, 3 finger breadths (patient’s fingers) should span the distance from chin to hyoid bone, while the distance from hyoid to thyroid should measure 2 finger breadths.

Mallampati score – grades the view of an open mouth, with class 3 or more predicting a difficult intubation

Obesity/obstruction – Epiglottitis or a tonsillar abscess can inhibit easy passage of an endotracheal tube.

Neck mobility – if limited, positioning is difficult and causes suboptimal views during intubation.

Cervical spine immobilization

When the patient arrives in the Emergency Department (ED) following a significant physical trauma, such as head injury or motor vehicle collision, it is crucial to consider the integrity of the cervical spine. If injury is present in this region, further manipulation or movement of the neck may lead to spinal cord damage. Therefore, evaluation and management of airway for these patients should go hand in hand with cervical spine immobilization.

If no specialized equipment is available, or until one is prepared for use, attempts to limit neck movement can be done using manual in-line stabilization, where the provider’s forearms or hands may be positioned at the sides of the patient’s head to prevent indirect movements that could exacerbate underlying injury (see Figure 3).

Cervical spine immobilization is then performed using a rigid cervical collar. It may be augmented with head blocks on lateral sides to limit movement further as the patient is evaluated for injury (see Figure 4). The thoracolumbar region of the spine is immobilized using a spinal backboard, which keeps the patient in a supine position with minimal external force on the spine. Frequently utilized in Emergency Medical Services (EMS) during extrication and transport, all efforts should be made to transition the patient off the spinal board in the ED as it is quite uncomfortable, with prolonged use associated with pressure ulcers and pain.

Breathing

The lungs perform the vital function of delivering oxygen from the airway to the alveoli through ventilation. Perfusion at the alveoli allows for gas exchange; therefore, effective ventilation and perfusion both play a key role in the availability and utilization of oxygen by the human body. Evaluation of the Breathing component assesses factors that would indicate a compromise in ventilation.

The chest inspection should look for respiratory rate, use of accessory muscles, position of trachea (midline versus deviated), symmetry of chest rise, and/or any visible trauma to the thorax. Auscultation evaluates breath sounds for any bilateral inequal air entry or presence of crackles, crepitus, or wheeze. Percussion, though sometimes useful, is often difficult to perform adequately in a resuscitation environment.

Let’s compare the findings in normal lungs, pleural effusion, and pneumothorax based on chest rise, trachea position, percussion, and auscultation.

Normal Lungs: Chest rise is symmetrical with the trachea in the midline position. Percussion reveals a resonant sound. Auscultation presents vesicular breath sounds peripherally and bronchovesicular sounds over the sternum, with no added sounds.

Pleural Effusion: Chest rise remains symmetrical, and the trachea is midline. Percussion is dull over the area of effusion, and auscultation shows decreased breath sounds in the region of the effusion.

Pneumothorax: Chest rise is unequal, and the trachea may be deviated in cases of tension pneumothorax. Percussion reveals a hyper-resonant sound in the area of the pneumothorax, and auscultation shows decreased breath sounds over the pneumothorax region.

Measuring oxygen saturation using pulse oximetry (spO2) provides a percentage of oxygen in circulating blood, with normal levels typically at 95% or above. However, in patients with chronic lung disease, baseline oxygen saturation levels may decrease and can be as low as 88% in many cases. For patients experiencing shortness of breath and showing signs of hypoxia, pulse oximetry readings below 94% suggest that supplemental oxygen may be necessary. This can be administered through various oxygen delivery systems, as outlined in Figure 5 and described below.

Figure 5 – Common equipment used in airway management 1- Nasal cannula, 2- Simple face mask, 3- Nebulizer,* 4- Non-rebreather mask, 5- Venturi mask valves, 6- Rigid suction tip, 7- Bag-valve mask device, 8- Oropharyngeal airway (OPA), 9- Nasopharyngeal airway (NPA), 10- Direct Laryngoscope, 11- Endotracheal tube with stylet, 12- Colorimetric end-tidal CO2 detector, 13- Bougie, 14- Laryngeal Mask Airway (LMA) *NOT an oxygen delivery device, used to administer inhaled medication such as bronchodilators and steroids CO2: Carbon dioxide

General concepts—We typically breathe in room air, which contains 21% oxygen. Each Liter per minute of supplemental oxygen provides an additional 4% inspired oxygen (FiO2) to the patient.

Nasal cannula – Administered through patient nostrils, can provide a maximum flow rate of 4-6 Liters per minute of oxygen, which equals roughly 37 – 45% FiO2

Simple face mask – Applied over the patient’s nose and mouth, can provide a maximum flow rate of 6-10 Liters per minute of oxygen, which equals roughly 40 – 60% FiO2

Venturi mask – Typically used in COPD, where over-oxygenation is avoided. Different colors deliver various flow rates to limit oxygen delivery to the required amount only; Blue (2-4L/min, FiO224%), White (4-6L/min, FiO2 28%), Yellow (8-10L/min, FiO235%), Red (10-12 L/min, FiO2 40%), Green (12-15 L/min, FiO260%)

Non-rebreather mask – Utilizes an attached bag with a reservoir of oxygenated air along with one-way valves on the mask to prevent rebreathing of expired air, optimizing oxygenation. It can provide a maximum flow rate of 15 Liters per minute of oxygen, which equals roughly 85 – 90% FiO2.

Non-invasive ventilation (CPAP/BiPAP) is a tight-fitting mask device that uses high positive pressure to keep the airway open and enhance oxygenation. It is particularly useful in conditions such as COPD exacerbation, acute pulmonary edema/heart failure, and sleep apnea.

Bag-valve mask device: A self–inflating bag attached to a reservoir delivers maximal, high-flow 100% oxygen. This method of manual ventilation is used in rescue breathing and oxygen delivery in nonresponsive or cardiopulmonary arrest patients.

Circulation

The circulation component of the Primary Survey evaluates the adequacy of perfusion by the cardiovascular system. The patient’s general appearance is assessed for signs of pallor, mottling, diaphoresis, or cyanosis, which indicate inadequate or deteriorating perfusion status. Pulses are checked centrally (e.g. carotid pulse, especially if patient with impaired breathing) and peripherally (e.g. radial) alongside hemodynamic assessment, including blood pressure and heart rate checks. Information from this segment also provides valuable insight into potential signs of shock. Extremities are palpated in order to determine any delays in capillary refill time (more than 2 seconds signifies inadequate perfusion, e.g. hypovolemia), peripheral edema in lower extremities (signs of heart failure), and skin temperature (cool or warm to touch).

In cases of trauma, systematic evaluation of circulation also seeks to ascertain areas of potential blood loss or collection, with interventions for any long-bone deformities and/or bleeding from open wounds performed as they are discovered.
Intravenous (IV) line insertion is also performed as part of the management of circulation, as any required fluid or blood products can then be administered through a large-bore IV line (16 gauge or higher). If IV insertion is difficult on multiple attempts, when volume resuscitation is urgently required, Intraosseous (IO) access should be sought to prevent delay in any needed treatment. Insertion of a peripheral venous line often occurs concomitant to blood extraction for any urgent laboratory investigations and/or point-of-care testing. Some common examples of tests performed on critically ill patients include venous blood gas, complete blood count, type and crossmatch, troponin, urea, electrolytes, and creatinine.

Finally, circulation assessment requires an evaluation of cardiac rhythm. Basic auscultation may reveal the rate and regularity of rhythm along with murmurs. However, a critically ill patient will also benefit from the immediate attachment of cardiac pads to the bare chest and connection to a cardiac monitoring device, which provides the physician with the patient’s current cardiac rhythm.

A normal sinus rhythm (Figure 6) consists of a P wave (atrial depolarization), followed by a QRS wave (ventricular depolarization – normally less than 120 ms), with a subsequent T wave (ventricular repolarization). P-R intervals typically have a duration of 120 – 200 ms. A regular rhythm, with a consistent P wave preceding QRS complexes, with a normal heart rate (between 60 – 100 beats per minute (bpm)) is required to consider a rhythm to be normal sinus on the cardiac monitor.

The American Heart Association’s (AHA) Advanced Cardiac Life Support (ACLS) course and guidelines outline a series of internationally recognized cardiac rhythms and their general management when encountered [2]. Some of the most important rhythms, along with the AHA bradycardia and tachycardia algorithms, are summarized below:

Several different conditions, including abnormal heart conduction, damage to the myocardium, metabolic disturbances, or hypoxia, can cause bradycardia. A lower heart rate can result in decreased perfusion to end-organs, such as the brain, with resultant signs and symptoms such as dizziness, confusion, shortness of breath or chest pains. Management (Figure 7.2) aims to treat the underlying cause and increase the heart rate (atropine, dopamine/epinephrine and/or cardiac pacing) if needed to restore the heart’s ability to perfuse organs adequately.

Tachycardia (Figure 8.1) is a heart rate of more than 100 bpm that may present as several types of waveforms on the cardiac monitor. Supraventricular tachycardia (SVT) originates in the upper chambers of the heart. The rapid heart rate prevents adequate filling of the heart between contractions, causing signs and symptoms such as dizziness, palpitations, or chest pain.

Management (Figure 8.2) typically involves Valsalva maneuvers, medication (e.g. adenosine), and/or synchronized cardioversion as needed to revert the rhythm back to baseline.

SVT produces a narrow-complex tachycardia (QRS segments < 120 ms). In comparison, monomorphic Ventricular Tachycardia (Figure 8.3) originates in the lower chambers of the heart and produces a wide-complex (QRS segments > 120 ms) tachycardia on the cardiac monitor. Similarly, this rhythm may cause dizziness, shortness of breath, or chest pain and is managed with medication or synchronized cardioversion.

ACLS algorithms often divide patients based on “stable” and “unstable” categories. This grouping aims to ascertain which individuals have a pathology severe enough to impair cardiac output to the point of causing serious inadequacies in end-organ perfusion. This ‘instability’ is manifested by altered mental status, ischemic chest pain, drastically low hemodynamic parameters (e.g. systolic BP < 90 mmHg), signs of shock, and signs of acute decompensated heart failure.

Disability

This segment evaluates the level of consciousness and responsiveness of the patient. Level of consciousness may be assessed generally using the AVPU scale (below);

Alert: fully alert patient
Verbal: some form of verbal response is present, though not necessarily coherent.
Pain: response to painful stimulus
Unresponsive: no evidence of motor, verbal or eye-opening response to pain

or more explicitly, using the Glasgow Coma Scale (GCS)

Choose the best response of patient
EYE OPENING
4: Spontaneously
3: To verbal command
2: To pain
1: No response

BEST VERBAL RESPONSE
5: Oriented and converses
4: Disoriented and converses
3: Inappropriate words; cries
2: Incomprehensible sounds
1: No response

BEST MOTOR RESPONSE
6: Obeys command
5: Localizes pain
4: Flexion withdrawal
3: Flexion abnormal (decorticate)
2: Extension (decerebrate)
1: No response

Exposure

Complete exposure of the patient may be necessary to completely evaluate for any external signs of infection, injury, and rash. This is especially useful in trauma, where log-rolling of the patient is included to ensure the back and spine are also included in a complete assessment for any traumatic injuries. As you expose the patient, obtain consent, be mindful of their dignity, and uncover each segment of the body sequentially, covering it back to prevent any hypothermia for the patient. A core temperature reading also completes vital sign measurements for the patient.

Practical implementation of the Primary Survey

The “cursory” primary survey

It may seem surprising to consider that virtually every patient who enters the Emergency Department, despite the severity of the illness, undergoes some form of a Primary Survey by the treating physician. However, the practicality of this becomes quite obvious when you consider a simple question frequently asked at the beginning of a patient encounter:

“How are you?”

An adequate response of “I am all right” or “Well, I have had this pain in my stomach…” seems fairly standard, but it addresses most of the components detailed in the previous section. A patient who can form words without difficulty or added sounds generally has an intact or patent Airway. Their ability to form words depends on air that has been sufficiently ventilated and moving through the vocal cords, hence the Breathing is adequate. An appropriate response to the question allows us to assume that Circulation adequately perfuses the brain to allow comprehension and formulation of new words oriented to the circumstances of the encounter, hence providing insight into Circulation and, to a degree, Disability.

Synchrony in the Emergency Department

Although systematic assessment during the Primary Survey is laid out in order, it is also important to note that an Emergency Department consists of teams of healthcare professionals who often have the personnel and resources to simultaneously perform tasks to efficiently address all components of the Primary assessment, without delay between segments.
In practice, an example of how synchrony works would involve a patient who, on initial, immediate assessment, is deemed to be in significant distress and/or critically ill. The patient is immediately moved into the ED to a resuscitation area, where team members expose the chest, attach cardiac pads to connect the patient to a cardiac monitor, obtain a fresh set of vital signs, including spO2monitoring, with IV cannula insertion, blood extraction for testing as needed. At the same time, a primary survey is conducted simultaneously by another physician who moves through Airway, Breathing, Circulation, Disability and Exposure. In more advanced systems, a member may be dedicated to each component of the Primary Survey.

Adjuncts

A number of resources are accessible to the Emergency Physician that may aid in diagnosing and investigating the critically ill patient. Utilizing these alongside the initial Primary Survey provides valuable, relevant information that can further guide clinical decision-making and diagnosis during evaluation.

Electrocardiogram – A 12-lead electrocardiogram provides a complete picture of the heart’s electrical activity in various vectors and segments, allowing for a more accurate evaluation for rhythm disturbances, such as in acute myocardial infarction, hyperkalemia, bundle branch blocks, and torsade de pointes. This often ties into the Circulation assessment and allows for a more comprehensive look into the heart’s electrophysiology.
Portable X-rays – Particularly in trauma, urgent chest and pelvic X-ray films can often be obtained without having to transfer the patient to Radiology, hence providing more information on suspected lung pathologies (e.g. pneumothorax, effusion/hemothorax) and pelvic abnormalities (e.g. fracture, displacement).
Urinary/ gastric catheters – Urinary catheters are useful to evaluate fluid status and monitor output for the patient undergoing volume resuscitation. When relevant, gastric tube insertion can assist in gastrointestinal decompression, if needed, as well as minimize the risk of aspiration in certain patients.
Point-of-Care Ultrasonography (PoCUS) – A rapidly evolving and increasingly prevalent modality in the ED is the ultrasound.[3] Various probes, at different frequencies, utilize ultrasound waves to provide the physician with real-time visualization of the body’s internal structures. These images are fast and often very reliable in determining major findings that can guide decision-making in critically ill patients (e.g. presence of post-traumatic intra-abdominal free fluid, pneumothorax, cardiac tamponade). Figure outlines some examples of information that can be extracted using PoCUS.

Reassessment

Each intervention performed in the Primary Survey should ideally be accompanied by a reassessment of vital signs and patient clinical status and a restarted Primary Survey beginning from Airway. Identifying any improvements, deteriorations, or non-responses that will be pivotal in guiding the initiation or discontinuation of further intervention as per the clinical case is crucial.

Focused History and Secondary Survey

If the patient is appropriately evaluated and stabilized following the Primary Survey, the treating physician may proceed with a focused history and secondary survey appropriate to the clinical circumstances. One example of a focused history incorporates the mnemonic SAMPLE to organize pertinent information as follows:

S – Signs/symptoms of presenting complaint

A – Allergies to any food or drugs

M – Medications (current, recent changes)

P – Pertinent past medical history

L – Last oral intake

E – Events leading to the illness or injury

A secondary survey in the Emergency Department is a more comprehensive physical examination performed systematically in a head-to-toe fashion to investigate any clinically relevant findings. In case of trauma, this also involves careful inspection for any missed injuries, deformities, or signs of underlying blood collection.

As the secondary survey is performed, relevant investigations and/or imaging may be ordered to augment the evaluation of the present clinical condition (e.g. Computerized Tomography (CT) of the brain after signs of basal skull fracture noted on inspection of the face and head). Information gathered from the survey and results of any ordered investigations, coupled with the clinical condition and/or response to therapy in the ED, if any, is used to determine patient disposition at the end of the ED encounter.

Revisiting Your Patient

You assist the Emergency Physician in performing a Primary Survey. The airway is patent, with the patient phonating in full sentences and breathing with mild tachypnea but no added sounds on auscultation. You initiate supplemental oxygen through a non-rebreather mask, with an increase in spO2 to 99%. You reassess and proceed through Airway, Breathing, and Circulation. As you discuss initiating IV fluids with your senior, the patient complains of worsening chest pain, palpitations, and dizziness.You attach the patient to the cardiac monitor and notice the rhythm below:

Cardiac pads have already been attached to the patient. Noting the presence of ischemic chest pain, you correctly identify the patient as having an unstable, narrow-complex tachycardia, most likely an SVT and prepare for synchronized cardioversion. Conscious sedation is conducted after explaining the procedure and obtaining consent from the patient. 50 joules of biphasic energy is then administered for synchronized electrical cardioversion. The rhythm changes on the monitor to the reading below:

You observe an organized rhythm but note that the patient is now unresponsive, with eyes closed and no palpable carotid pulse.

Basic Life Support

Cardiopulmonary arrest occurs when the heart suddenly stops functioning, resulting in lack of blood flow to vital organs in the body, such as the lungs and brain. Therefore, signs of arrest are manifested as a lack of breathing (apnea), lack of pulse and unresponsiveness. The most common cause of cardiac arrest is coronary artery disease.[4] Respiratory arrest refers to a cessation of lung activity, but with a present, palpable pulse and functioning heart.
The International Liaison Committee on Resuscitation (ILCOR) and the American Heart Association (AHA) are some of the key figures who have developed international guidelines on the recognition and management of cardiac arrest patients.[5] Basic Life Support (BLS) and Advanced Cardiac Life Support (ACLS) courses were established to optimize the workflow and, therefore, patient outcomes in Cardiopulmonary Resuscitation (CPR).

CPR forms the cornerstone of BLS to effectively maintain the victim’s circulatory and ventilatory function until circulation either spontaneously returns or is hopefully restored through intervention. The general concepts within BLS are outlined below:

1. A person who has a witnessed collapse, lack of response or who is suspected of being unresponsive due to cardiac arrest should be approached for further assessment and management. However, it is important for the rescuer to first determine whether the scene is safe around the patient before attempting any intervention. An example of this would be a victim drowned in water, who should be removed from the body of water onto a dry surface prior to attempting life-saving chest compressions or defibrillation.

2. Check for responsiveness. Firmly tapping both shoulders with the palms of your hands and a clear, verbal prompt, such as “Hey, are you okay?” should be incorporated to ensure that the victim is, indeed, unresponsive to an otherwise arousable stimulus.

3. You have determined that the patient is unresponsive. If you are alone, shout loudly and clearly for help and assistance. If no help is nearby, call Emergency Medical Services using your mobile phone.

4. Open the patient’s airway (tilt chin upward into sniffing position). Palpate the carotid pulse by placing two fingers (index and middle finger) just lateral to the trachea on the side closest to you while simultaneously observing the chest for any spontaneous chest rise (breathing). The pulse check should take a minimum of five (5) seconds but no more than 10 seconds to avoid delay in life-saving intervention.

5. When help is available, the chain of survival begins by activating the Emergency Response System. In addition to activating the Emergency Response, ask the person who has responded to your call for help getting an Automated External Defibrillator (AED) device. An example of instruction to a bystander (out of hospital) would be to ‘call an ambulance and get an AED!’. Inside a hospital, if another healthcare provider has come to aid, you may ask them to ‘activate the Emergency Response System/’Code Blue’ and get the crash cart/AED.’

6. Begin high-quality chest compressions. Hands are placed with fingers interlaced to exert pressure using the heel of one hand at the center of the chest, over the lower half of the breastbone (sternum), in line with the nipples (in men), with shoulders directly over your hands and arms straight at a perpendicular angle to the victim’s chest. High-quality chest compression is one of the few variables which have been evidenced to improve patient survival in cardiac arrest.

Keep the following features in mind to maintain high-quality chest compressions:

More than 80% of the time in resuscitation or more should be spent on compressions (Chest compression fraction of > 80%)
The frequency of compressions should follow a rate of 100–120 compressions per minute.
Compression depth in adults is at least 2 inches. In infants and children, depth should be at least one-third of the anterior-posterior diameter of the chest.
After each compression, the hands should be withdrawn to allow adequate chest recoil and fill the heart between compressions.
Minimize interruptions in chest compression
Avoid hyperventilation (see next point).

7. Compressions should follow the ratio 30:2, that is, 30 compressions followed by 2 rescue breaths delivered by a mouth barrier device (pocket mask) in the sniffing position or a Bag-valve mask (BVM) device if another rescuer is present to manage the airway in hospital. The BVM’s mask should be held with a tight seal using the E-C technique over the bridge of the nose and covering the mouth.

Breaths should be over 1 second, with enough air pushed in to observe a chest rise and no hyperventilation or excessive bagging of the BVM to avoid gastric insufflation. Two attempts at rescue breaths are performed, minimizing time to under 10 seconds and resuming chest compressions immediately after. If a definitive airway (e.g. endotracheal tube) is in place, resume compressions without pause at a rate of 100-120 compressions per minute while breaths are delivered once every 6 seconds.

8. Once an AED or cardiac monitor/defibrillator is available, place the pads on the victim’s bare chest (dry the skin if wet) in either an anterior-lateral or anterior-posterior position.When in doubt, follow the machine’s prompts and the instructions on the pads themselves to guide placement.

9. Follow the prompts on the AED. Stop compressions when the device analyzes rhythm and stay clear of the patient (not touching any part of the patient’s body). During an in-hospital resuscitation, as per ACLS workflow, stay clear, as the team leader should analyze the initial rhythm to ascertain the presence of a shockable or non-shockable rhythm. Either way, the device or team leader should prompt whether a shock is advised. Continue compressions as the device charges, but ensure that all rescuers are clear of the patient when the shock is delivered using the AED/defibrillator device.

A victim who is unresponsive but has a palpable pulse has respiratory arrest, which is managed using rescue breathing only. Breaths are delivered once every 6 seconds without chest compressions while transport to a higher level of care and/or management of any underlying cause for the condition is initiated.

Advanced Cardiac Life Support

The Advanced Cardiac Life Support algorithms were designed to deliver a higher level of resuscitative care where providers with increased training and improved resources are available. This type of augmented management is customary to the Emergency Department, where a Rapid Response Team or Code Blue team would respond when activated and initiate a more team-based approach to cardiopulmonary resuscitation.

Instead of an AED, in-hospital settings have a cardiac monitor/defibrillator, usually mounted atop a crash cart consisting of a CPR back-board (to support chest compressions by providing a firm surface to use under the patient’s chest), drawers with medication used during cardiac arrest, and various equipment for airway management and IV/IO access. Once brought to the bedside, the cardiac pads are similarly placed on the patient’s chest while BLS maneuvers (chest compressions and rescue breaths) continue. Once placed, however, compressions should be paused to assess the cardiac monitor’s cardiac rhythm. The type of rhythm should be identified as ‘shockable’ or ‘non-shockable’ (Figure 17s).

“Shockable” rhythms (pulseless Ventricular Tachycardia and Ventricular Fibrillation) are a product of aberrant electrical conduction of the heart. Rapid, early correction of this rhythm is the most important step in returning the body to its normal circulatory function. Early defibrillation is one of the few variables that has been evidenced to improve patient survival in cardiac arrest, the other notable one being high-quality chest compressions.[6]

Defibrillation involves using an asynchronous 200J of biphasic (360J if monophasic) energy, delivering an electric current through the cardiac pads attached to the patient’s chest to revert the heart to a rhythm that can sustain spontaneous circulation. Chest compressions should be ongoing while charging, but all persons should stay clear of the patient when shock is being delivered, and this is frequently verified with verbal feedback (‘Clear!’) before pressing the defibrillator button to deliver the shock. Immediately after the shock, chest compressions should resume to minimize interruptions between compressions.

Two minutes of chest compressions and rescue breaths make up each cycle of CPR, at the end of which a rhythm check should be performed for any changes and/or presence of pulse. Figure 18 outlines the ACLS algorithm used to manage shockable and non-shockable rhythms in cardiac arrest. Early shock in shockable rhythms is followed by a cycle of CPR, a second shock if still with a shockable rhythm, after which 1mg of IV epinephrine is given, with subsequent doses every 3 to 5 minutes. During the third cycle of CPR, after 3 shocks have been delivered for a persistent shockable rhythm, a bolus of IV Amiodarone 300mg is typically administered, with a dose of 150mg in a subsequent CPR cycle if still with a shockable rhythm.

“Non-shockable” rhythms (pulseless electrical activity (PEA) and asystole) are not typically a product of disorganized electrical activity in the heart. Instead, an underlying cause has resulted in cardiac arrest for these patients. While the majority of cardiac arrest is caused by coronary artery disease, the consideration of reversible causes by use of the H’s (hypovolemia, hypoxia, hyper-/hypokalemia, hydrogen ions (acidosis), and hypothermia) and T’s (thrombosis/embolism, toxins, tension pneumothorax, and cardiac tamponade) may help recognize and manage other possible etiologies in patients.

The management of non-shockable rhythms focuses on consistent, high-quality CPR, with regular pulse checks every 2 minutes, addressing reversible causes, and administering IV epinephrine 1mg every 3 to 5 minutes.
A palpable pulse with measurable blood pressure signals the Return of Spontaneous Circulation (ROSC).

Resuscitation Team Dynamics

The Emergency Department is equipped with the resources and personnel to provide care beyond basic life support. Resuscitation is optimized when multiple providers work together to effectively perform tasks toward management of the patient, thereby multiplying the chances of a successful outcome for the patient. A high-performance team typically consists of members allocated to the following roles and responsibilities:

Airway – Opens and maintains the airway. Manages suctioning, oxygenation, and ventilation (Bag-valve mask) and assesses the need for a definitive airway if needed.
Medication – Inserts and maintains IV/IO access. Manages medication administration and fluids.
Monitor/defibrillator – Ensures attached cardiac pads and AED/cardiac monitor/defibrillator device are working appropriately to display the patient’s cardiac rhythm in clear view of the team leader. Administers shocks using the devices as needed. May alternate with the compressor every 5 cycles or 2 minutes to prevent compression fatigue
Compressor – Performance of high-quality chest compressions as part of CPR for the cardiac arrest patient. Focuses on quality and consistency of compressions. You may switch to another standby compressor or monitor/defibrillator every 5 cycles or 2 minutes if compressions are affected by fatigue.
Recorder – Documents the timing of medication, intervention (shocks, compression), and communicates these to the Team Leader, with prompts to enable timely dosing of frequent medication (e.g., ensuring epinephrine every 3 to 5 minutes is administered as per the verbalized order)
Team leader – A defined leader who coordinates the team’s efforts and organizes them into roles and responsibilities that are clear, well-understood, and within their individual limitations. Provides explicit instructions and direction to the resuscitation effort, focused on patient care and optimized performance from all team members. Promotes understanding and motivates members, identifying any potential deficit or depreciation of quality during resuscitation and facilitating improvement in performance as needed.

All team members are encouraged to conduct themselves with mutual respect and practice closed-loop communication, where each message or order is received with verbal confirmation of understanding, then execution of the order, centralizing all information back to the team leader. Figure 19 provides an example of the possible placement of each member during resuscitation that may optimize their workflow through the resuscitation attempt. Ideally, the team leader remains at the foot of the bed, in clear view of all members, with involvement limited to coordination of the team’s efforts and minimal direct execution of tasks.

Post Arrest Care

If the patient is found to have Return of Spontaneous Circulation (ROSC), post-cardiac arrest care should be initiated to enhance the preservation of brain tissue and heart function. This involves a sequential assessment and optimization of Airway, Breathing, and Circulation in the initial stabilization phase. A definitive airway may be placed so ventilation is more appropriately controlled, with parameters set to optimize oxygen administered with ventilatory function. Figure 20 outlines the ACLS algorithm and parameters often used to help guide post-cardiac arrest care. Circulation incorporates fluids, vasopressors, and/or blood products to achieve an adequate systolic blood pressure above 90 mmHg, with Mean Arterial Pressure of at least 65 mmHg typically indicating perfusion within stable parameters.

It is imperative to obtain a 12-lead ECG early to ascertain the presence of an ST-elevation myocardial infarction (STEMI), which will require expedited transfer of the patient to a Cath Lab for definitive reperfusion therapy. The patient’s responsiveness should be reassessed, and the determination for additional investigation should be performed in conjunction with other critical care management as needed.

Of note, unresponsive patients may benefit from Targeted Temperature Management (TTM), which involves the maintenance of core body temperature at a target of 32 – 36 ℃ for 24 hours, or preferably normothermia at 36 °C to 37.5 °C with an emphasis on prevention of hyperthermia, in order to protect and optimize brain recovery post-arrest.[7]

Almost all cardiac arrest survivors will require a period of intensive care observation and management. If no immediate intervention is needed (e.g., reperfusion therapy), patients inside a hospital will need to be transitioned to an Intensive Care Unit (ICU) for further care.

What do you need to know?

Emergency Medicine, especially in critical care, emphasizes a systematic approach to the unwell patient.
The Primary Survey is designed to recognize and address life-threatening conditions effectively and timely.
The Primary Survey components are Airway (& and C-spine in trauma), Breathing, Circulation, Disability, and Exposure.
If an intervention is performed at any level of the survey, you must reassess the patient by commencing the Primary Survey again, starting with Airway.
Reassess and review your patient for changes frequently.
Many of the actions performed in the initial assessment of the critically ill patient may occur simultaneously when more team members are present in an Emergency Department. Do not let the chaos of the scene distract you from completing each step of the assessment.
The AHA has well-established guidelines for assessing and managing patients through the Primary Survey. Use the algorithms and the patient’s status as ‘stable’ or ‘unstable’ to guide the management of recognized pathologies, especially in Circulation.
The ED is home to a variety of adjuncts, including portable X-rays, ECG, and point-of-care ultrasound, which can provide the physician with rapid, readily accessible information to guide management.
Remember the SAMPLE mnemonic for a focused history in the critically ill patient.
An unresponsive patient should be immediately recognized, and Emergency Response Systems should be activated.
Performance of Basic and Advanced cardiac life support focuses on preserving blood circulation transiently to maintain the perfusion of organs, such as the brain, until the cause of the condition is reversed or managed.
The majority of cardiac arrest is caused due to coronary artery disease.
The two most important predictors of patient survival in cardiac arrest are high-quality CPR and early defibrillation (for a shockable rhythm)
An effective resuscitation in the ED often relies on the concerted efforts of multiple team members, led by a team leader who coordinates tasks in an organized, effective way to improve patient survival and outcomes.

Author

Mohammad Anzal Rehman

EM Residency Graduate from Zayed Military Hospital in Abu Dhabi, UAE. Founder/President of the Emirates Collaboration of Residents in Emergency Medicine (ECREM). Editor-in-Chief for the Emirates Society of Emergency Medicine (ESEM) Monthly Newsletter. I have a vested interest in sharing updated knowledge and developing teaching tools. As a healthcare professional, I continually strive to incorporate the newest clinical research into practice and am an active advocate for the use of Point of Care Ultrasonography (POCUS) in the ED.

Listen to the chapter

References

Reynolds T. Basic Emergency Care: Approach to the Acutely Ill and Injured. World Health Organization; 2018.
2020 Advanced Cardiac Life Support (ACLS) Provider Manual. American Heart Association; 2021.
Hashim A, Tahir MJ, Ullah I, Asghar MS, Siddiqi H, Yousaf Z. The utility of point of care ultrasonography (POCUS). Ann Med Surg (Lond). 2021;71:102982. Published 2021 Nov 2. doi:10.1016/j.amsu.2021.102982
Cardiac Arrest Registry to Enhance Survival (CARES) 2022 Annual Report; 2022, https://mycares.net/
Wyckoff MH, Singletary EM, Soar J, et al. 2021 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Neonatal Life Support; Education, Implementation, and Teams; First Aid Task Forces; and the COVID-19 Working Group. Resuscitation. 2021;169:229-311. doi:10.1016/j.resuscitation.2021.10.040
Soar J, Böttiger BW, Carli P, et al. European Resuscitation Council Guidelines 2021: Adult advanced life support [published correction appears in Resuscitation. 2021 Oct;167:105-106]. Resuscitation. 2021;161:115-151. doi:10.1016/j.resuscitation.2021.02.010
Lüsebrink E, Binzenhöfer L, Kellnar A, et al. Targeted Temperature Management in Postresuscitation Care After Incorporating Results of the TTM2 Trial. J Am Heart Assoc. 2022;11(21):e026539. doi:10.1161/JAHA.122.026539

Acknowledgements

Marina Margiotta – Illustrator
Paddy Kilian – Emergency Physician – Mediclinic City Hospital, Dubai, Director of Academic Affairs – Mohammed Bin Rashid University Of Medicine and Health Sciences
Rasha Buhumaid – Consultant Emergency Physician – Mediclinic Parkview Hospital, Dubai, Assistant Professor of Emergency Medicine – Mohammed Bin Rashid University Of Medicine and Health Sciences, President of the Emirates Society of Emergency Medicine (ESEM)
Amog Prakash – Medical Student – Mohammed Bin Rashid University Of Medicine and Health Sciences
Fatima Al Hammadi- Medical Student – Mohammed Bin Rashid University Of Medicine and Health Sciences

Reviewed By

Arif Alper Cevik, MD, FEMAT, FIFEM

Can you identify the signs of human trafficking in the Emergency Room?

December 20, 2021December 11, 2021 ~ Brenda Feres, Brazil ~ Leave a comment

Definition and Importance

Human trafficking is a global problem enclosing the spheres of international law, human rights, organized crime, public health and medicine. It is best defined by the United Nations Protocol to Prevent, Suppress and Punish Trafficking in Persons as “the recruitment, transportation, transfer, harbouring or receipt of persons, by means of the threat or use of force or other forms of coercion, of abduction, of fraud, of deception, of the abuse of power or a position of vulnerability or the giving or receiving of payments or benefits to achieve the consent of a person having control over another person, for exploitation. Exploitation shall include, at a minimum, the exploitation of the prostitution of others or other forms of sexual exploitation, forced labour or services, slavery or practices similar to slavery, servitude or the removal of organs.”

According to the Federal Bureau of Investigation (FBI), human trafficking is considered the third-largest criminal activity in the world. Despite issues regarding data collection, the US State Department was able to report that around 20,000 people per year are trafficked inside the United States. It is also estimated that up to 900,000 people per year are being transported across borders with the intention of slavery and exploitation.

Why should physicians care about it?

A 2014 study showed that 87.8% of human trafficking survivals had access to healthcare services during their trafficking situation and of this, 68.3% went to the emergency room. The data above highlights the importance of healthcare professionals, especially those at the emergency department, when it comes to the identification and help of trafficking victims. It also reinforces the role of the emergency doctors as front-line healthcare providers for those in vulnerable situations and/or who lack proper medical care.

What are the signs that can be marked as "red flags" to identify victims of human trafficking?

According to the guidelines provided by National Human Trafficking Resource Center (NHTRC) there are some indicators, and they are divided into General Indicators and Health Indicators or consequences of Human Trafficking. They can be physical and/or mental signs. It is important to say that not all the victims will have the same indicators and each sign isolated may not be a trafficking situation. However, if several “red flags” are detected, further assessment may be needed.

GENERAL INDICATORS

The patient may tell an inconsistent story or be reluctant to describe details and answer questions about the injury or illness.
The accompanying individual does not let the patient have privacy or even speak for themselves.
They are unable to provide his/her own address and/or are unaware of the current time and location.
The patients` document may not be in his/her possession, and rather held by the accompanying individual.
The patient may not have the appropriate clothing for the weather.
The presence of tattoos or any branding form demonstrating possession or serial numbers and bar codes may be found in the patient’s body.

PHYSICAL INDICATORS

Signs of abuse or inexplicable injuries such as bruises, burns, cuts, wounds, blunt force trauma, broken teeth, fractures or any other sign of torture such as restraint marks
Neurological conditions such as unexplained memory loss or traumatic brain injury
Dietary issues such as extreme weight loss or malnutrition
Signs of potentially forced substance abuse
Issues regarding the reproductive system such as Sexually Transmitted Diseases (STDs), genitourinary problems, forced abortions or several unwanted pregnancies.
Effects of prolonged exposure to unhealthy environments such as extreme temperatures, industrial or agricultural chemicals
Somatization symptoms
Poor dental hygiene
Untreated skin infections

MENTAL HEALTH INDICATORS

Anxiety
Post Traumatic Stress Disorder
Depression with or without suicide thoughts
Nightmares and/or flashbacks
Hostile behavior
The patient may present with a feeling of disorientation or an unrealistic perception of his/her surroundings.
Stockholm syndrome
Paranoid or extreme fearful behavior

It is important to keep in mind that the signs presented above are not exclusive to a trafficking situation and many other clinical conditions may cause the appearance of those groups of symptoms. That being said, if after spotting some “red flags” you are still unsure whether or not that patient is a potential victim, there are a few screening questions you can ask that might help to confirm your suspicions, such as:

Are you in possession of your identification documents?
How is a normal day at your work?
How is it like at the place where you work?
Describe the place where you sleep and eat.
Are you free to come and go whenever you please?
Do you get paid for your work?
Where is your family?
Is anyone threatening you?

What to do in case you come in contact with a victim?

Dealing with trafficking victims is a very sensitive matter which requires discretion and an approach centered on the victim. That means once it is confirmed that the situation is indeed about human trafficking, the doctor’s aim is to try to provide a safe environment and inform the person of his/her rights. In order to do that, you should try to meet the patient`s basic needs, always trying to build trust and rapport, avoiding any potential re-traumatization situation.

Some protocols will depend on the specific situation. It is also important to know that legal requirements regarding contacting the authorities will be different in each country. That said, it is your responsibility as an emergency doctor to be informed about the protocol regarding your geographic location.

In the US, there is a National Hotline (1-888-373-7888) that provides the victims with a safe and confidential space to talk and report the trafficking. This line is operational 24/7 and offers access in more than 200 languages.

In conclusion, doctors have a privileged position when it comes to recognizing and helping human trafficking victims. That is why it is very important to be attentive to spot possible “red flags” and be informed of the right protocols to follow in case you need to assist a victim.

References and Further Reading

United Nations. Annex II: The Definition of Trafficking in Persons and the Mandate for the Global Report Trafficking in Persons: Universally Defined in the UN Trafficking in Persons Protocol.; 2016. https://www.unodc.org/documents/data-and-analysis/glotip/Annex_II_-_Definition_and_mandate.pdf.
U.S. Department of Justice. (2019). Human trafficking/involuntary servitude. Federal Bureau of Investigation. Retrieved from https://www.fbi.gov/investigate/civil-rights/human-trafficking
Mukherji P. Recognizing Human Trafficking Victims in the Emergency Department. Relias Media. https://www.reliasmedia.com/articles/134799-recognizing-human-trafficking-victims-in-the-emergency-department. Published March 2015. Accessed August 2021.
Lederer, L. J., & Wetzel, C. A. (2014). The health consequences of sex trafficking and their implications for identifying victims in healthcare facilities. Annals of Health Law, 23(1), 61–91
Baldwin S, Eisenman D, et al. Identification of human trafficking victims in health care settings. Health Hum Rights 2011;13:E36-E49
Identifying Victims of Human Trafficking: What to Look for in a Healthcare Setting. National Human Trafficking Resource Center. https://humantraffickinghotline.org/sites/default/files What%20to%20Look%20for%20during%20a%20Medical%20Exam%20-%20FINAL%20-%202-16-16.docx.pdf. Accessed August 2021.
Recognizing and Responding to Human Trafficking in a Healthcare Context. National Human Trafficking Resource Center. https://humantraffickinghotline.org/sites/default/filesRecognizing%20and%20Responding%20to%20Human%20Trafficking%20in%20a%20Healthcare%20Context_pdf.pdf. Accessed August 2021.
Cyrus, Norbert, and Dita Vogel. “Evaluation As Knowledge Generator And Project Improver. Learning From Demand-Side Campaigns Against Trafficking In Human Beings.” Contemporary Readings in Law and Social Justice, vol. 10, no. 1, Addleton Academic Publishers, Jan. 2018, p. 57.
DILG Chief Optimistic of ASEAN States’ Support vs. Trafficking in Persons.” MENA Report, Albawaba (London) Ltd., May 2017, p. n/a.
Trafficking in persons Definition: 2k Samples | Law Insider. https://www.lawinsider.com/dictionary/trafficking-in-persons

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Question Of The Day #63

November 12, 2021November 18, 2021 ~ Joseph Ciano, USA ~ Leave a comment

Which of the following is the most appropriate next step in management for this patient’s condition?

Explanation

This patient presents to the Emergency Department after a high-speed motor vehicle accident in the setting of alcohol intoxication. On examination, he is intoxicated with a GCS of 14 (normal GCS is 15). The first step in evaluating any trauma patient involves the primary survey. The primary survey is also known as the “ABCDEFs” of trauma. This stands for Airway, Breathing, Circulation, Disability, Exposure, and FAST exam (Focused Assessment with Sonography in Trauma). Each letter should be assessed in alphabetical order to avoid missing a time sensitive life-threatening condition. The primary survey should be conducted prior to taking a full history.

After the primary survey, a more detailed physical exam (secondary survey) is conducted, followed by interventions and a focused patient history. This patient is intoxicated but is awake with a patent airway. Endotracheal intubation (Choice C) is not indicated. Neurosurgical consultation (Choice D) is also not indicated at this stage as there is no concrete information to indicate a surgical emergency. CT imaging may demonstrate a cervical spine fracture or intracerebral bleeding, but these results are not provided by the question stem. A CT scan of the head without contrast (Choice B) is a reasonable test for this patient given his significant mechanism of injury and intoxication on exam. However, both a CT scan of the head and cervical spine (Choice A) should be ordered due to the patient’s intoxication creating an unreliable physical exam. Alcohol intoxication or drug use can alter a patient’s ability to sense pain and provide accurate information. The presence of intoxication should always raise awareness for possible occult injuries.

Of note, intoxication and altered mental status are indications to perform a CT scan of the cervical spine based on a well-validated decision-making tool known as the NEXUS criteria (National Emergency X-Radiography Utilization Study). Other criteria on the NEXUS tool that support CT cervical spine imaging are midline spinal tenderness, the presence of a focal neurologic deficit, or the presence of a distracting injury (i.e., femur fracture). The Canadian C-Spine Rule and Canadian CT Head Rule are other validated decision-making tools to help a clinician decide on whether or not to order CT head or cervical spine imaging. Correct Answer: A

References

MDCalc. (2020). Calculated decision support for emergency medicine practice subscribers. https://www.ebmedicine.net/media_library/files/Trauma-Imaging-Resuscitation-CD.pdf
Lalani, N. (2013). My approach to clearing C-spines. Canadiem. https://canadiem.org/clearing-the-c-spine/

[cite]

Question Of The Day #60

October 22, 2021August 28, 2021 ~ Joseph Ciano, USA ~ Leave a comment

Which of the following is the most likely cause for this patient’s condition?

Explanation

This first-trimester pregnant patient presents with generalized weakness, nausea, and vomiting. She is hypotensive and tachycardic with no sign of urinary infection on the urinalysis. The many ketones in the urine indicate the patient has inadequate oral nutrition and is breaking down muscle and adipose tissue for energy. This is likely related to the persistent vomiting the patient is experiencing. This patient has hyperemesis, a common condition in the first trimester of pregnancy that is caused by rising levels of beta-human chorionic gonadotropin (BHCG). Treatment for this patient should include IV hydration and antiemetics. Admission criteria for these patients includes intractable vomiting despite antiemetic administration, over 10% maternal weight loss, persistent ketone or electrolyte abnormalities despite rehydration, or uncertainty in the diagnosis.

The fluid losses caused by vomiting in this condition result in hypovolemic shock (Choice B). Distributive shock (Choice C) is caused by other conditions, like sepsis, anaphylaxis, and neurogenic shock. A ureteral stone (Choice D) is unlikely as the patient does not report any abdominal, back, or flank pain. The urinalysis also does not show any hematuria, which is a common sign of a ureteral stone. Pyelonephritis (Choice A) can cause vomiting and septic shock which can result in hypotension and tachycardia. However, there is no sign of infection in the urinalysis provided, no fever, and no back or flank pain. The best answer is choice B.

References

Pickens, A. (2018). EM in 5: Shock. EMDocs. Retrieved from http://www.emdocs.net/em-in-5-shock/
Richards JB & Wilcox SR. (2014). Diagnosis and management of shock in the emergency department. EB Medicine, 16(3), 1-24. Retrieved from https://www.cmua.nl/Cmua/Inwerken_files/0314%20Shock.pdf
Streitz M. (2017). Hyperemesis gravidarum. EmDocs. Retrieved from http://www.emdocs.net/hyperemesis-gravidarum/

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Question Of The Day #59

October 15, 2021August 28, 2021 ~ Joseph Ciano, USA ~ Leave a comment

Which of the following is the most likely cause for this patient’s respiratory condition?

Explanation

This patient presents to the Emergency Department with palpitations, generalized weakness, and shortness of breath after discontinuing all her home medications. She has hypotension, marked tachycardia, and pulmonary edema (crackles on lung auscultation). The 12-lead EKG demonstrates atrial fibrillation with a rapid ventricular rate. This patient is in a state of cardiogenic shock and requires prompt oxygen support, blood pressure support, and heart rate control.

Pulmonary embolism (Choice A) can sometimes manifest as new atrial fibrillation with shortness of breath and tachycardia, but pulmonary embolism initially causes obstructive shock. If a pulmonary embolism goes untreated, it can progress to right ventricular failure, pulmonary edema, and cardiogenic shock. This patient has known atrial fibrillation and stopped all her home medications. The abrupt medication change is a more likely cause of the patient’s cardiogenic shock. Dehydration (Choice D) and systemic infection (Choice D) are less likely given the above history of abruptly stopping home maintenance medications. Untreated cardiac arrythmia (Choice B) is the most likely cause for this patient’s pulmonary edema and cardiogenic shock.

The chart below details the categories of shock, each category’s hemodynamics, potential causes, and treatments.

References

Morgenstern J. (2015). An approach to undifferentiated hypotension. First10EM. Retrieved from https://first10em.com/undifferentiated-hypotension/
Pickens, A. (2018). EM in 5: Shock. EMDocs. Retrieved from http://www.emdocs.net/em-in-5-shock/
Richards JB & Wilcox SR. (2014). Diagnosis and management of shock in the emergency department. EB Medicine, 16(3), 1-24. Retrieved from https://www.cmua.nl/Cmua/Inwerken_files/0314%20Shock.pdf

[cite]

Question Of The Day #58

October 8, 2021August 28, 2021 ~ Joseph Ciano, USA ~ Leave a comment

Which of the following is the most appropriate next step in management?

Explanation

This cirrhotic patient presents to the Emergency Department with epigastric pain after an episode of hematemesis at home. His initial vital signs are within normal limits. While waiting in the Emergency Department, his clinical status changes. The patient has a large volume of hematemesis with hypotension and tachycardia. This patient is now in hemorrhagic shock from an upper gastrointestinal bleed and requires immediate volume resuscitation. The most common cause of upper gastrointestinal bleeding is peptic ulcer disease, but this patient’s cirrhosis history and large volume of hematemesis should raise concern for an esophageal variceal bleed. IV Pantoprazole (Choice D) is a proton pump inhibitor that helps reduce bleeding in peptic ulcers, but it does not provide benefit in esophageal varices. Volume repletion is also a more important initial step than giving pantoprazole. IV Ceftriaxone (Choice C) helps reduce the likelihood of infectious complications in variceal bleed patients. This has a mortality benefit and is a recommended adjunctive treatment. However, rapid volume resuscitation is a more important initial step. IV crystalloid fluids, like normal saline (Choice A), are helpful in patients with hypovolemic shock (i.e., dehydration, vomiting), distributive shock (i.e., sepsis, anaphylaxis), and obstructive shock (i.e., tension pneumothorax, etc.). Hypovolemic shock due to severe hemorrhage (hemorrhagic shock) requires blood products, not crystalloid fluids which can further dilute blood and cause coagulopathy. Administration of packed red blood cells (Choice B) is the best next step in management in this case.

References

Long, B. (2018). EM@3AM: Gastroesophageal varices. EmDocs. Retrieved from http://www.emdocs.net/em3am-gastroesophageal-varices/
Pickens, A. (2018). EM in 5: Shock. EMDocs. Retrieved from http://www.emdocs.net/em-in-5-shock/
Richards JB & Wilcox SR. (2014). Diagnosis and management of shock in the emergency department. EB Medicine, 16(3), 1-24. Retrieved from https://www.cmua.nl/Cmua/Inwerken_files/0314%20Shock.pdf

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Cryptic Shock – Identifying the Unseen (PART 1)

October 4, 2021August 23, 2021 ~ Gayatri Lekshmi Madhavan, India ~ Leave a comment

Case Presentation

A 68-year-old man presented to the Emergency Department with complaints of breathing difficulty and fever for three days. The patient is a known diabetic and hypertensive.

After detailed history taking, clinical examination, and radiological workup, the patient was diagnosed with right-sided lobar pneumonia (Community-acquired) and immediately started on intravenous antibiotics. In addition, necessary cultures and blood samples were taken for evaluation.

At the time of presentation, his vitals were HR – 92/min, BP – 130/70mmHg, RR – 30/min, SpO2 – 90% with RA à 96% with 2L O2. He underwent bladder catheterization.

During the 1st hour in the ER, the patient had a very low urine output, which continued for the next few hours. Lactate levels were more than 4mmol/L.

Based on the symptoms, oliguria, and hyperlactatemia, the patient was diagnosed to have sepsis and was initiated on fluid resuscitation. After 2 hours, the patient remained oliguric still, and his BP declined to 120/70mmHg.

After 6 hours, the patient’s BP became 110/60mmHg (MAP – 77). He became anuric and developed altered sensorium. Since he did not meet the criteria of septic shock, he was continued on IV fluids and antibiotics.

After 12 hours, the BP became 80/40mmHg (MAP – 63mmHg) à developed Multiorgan Dysfunction Syndrome. He was then started on vasopressors and mechanical ventilation.

By day 3, the patient further deteriorated and went into cardiac arrest. ROSC was not achieved.

Case Analysis

The treatment initiated was based on protocols like Surviving Sepsis Guidelines and Septic Shock management. So how did the process fail in order to adequately resuscitate this patient? Could something have been done more differently?

The case you read above is a very common scenario. Approximately 30% of the people coming to the ER are hypertensive, and around 10% have diabetes mellitus. They form a huge population, among whom the incidence of any other disease increases their morbidity and early mortality.

Before we delve into the pathology in these patients, let us look at the basic definitions of shock/hypotension.

SBP < 90mmHg
MAP < 65 mmHg
Decrease in SBP > 40mmHg
Organ Dysfunction
Hyperlactatemia

Shock: A state of circulatory insufficiency that creates an imbalance between tissue oxygen supply (delivery) and demand (consumption), resulting in end-organ dysfunction.
Septic Shock: Adult patients can be identified using the clinical criteria of hypotension requiring the use of vasopressors to maintain MAP of 65mmHg or greater and having a serum lactate level greater than 2 mmol/L persisting after adequate fluids resuscitation.
Cryptic Shock: Presence of hyperlactatemia (or systemic hypoperfusion) in a case of sepsis with normotension.

Based on all the information given above;

what do you think was wrong with our patient?
What kind of shock did he have?
Could we have managed him any other way?
When should we have started inotropes?
Did the fact that he was hypertensive and diabetic have to do with his early deterioration? If so, how?
When did the patient-first develop signs of shock?
What are the different signs and symptoms of shock, and how are they recognized in the ER?

Keep your answers ready…

Part 2 of Cryptic Shock Series – Vascular Pathology and What is considered ‘Shock’ in Hypertensive patients

Part 3 of Cryptic Shock Series – Individualised BP management

Part 4 of Cryptic Shock Series – Latest Trends

References and Further Reading

Ranzani OT, Monteiro MB, Ferreira EM, Santos SR, Machado FR, Noritomi DT; Grupo de Cuidados Críticos Amil. Reclassifying the spectrum of septic patients using lactate: severe sepsis, cryptic shock, vasoplegic shock and dysoxic shock. Rev Bras Ter Intensiva. 2013 Oct-Dec;25(4):270-8. doi: 10.5935/0103-507X.20130047.
Singer M, Deutschman CS, Seymour CW, Shankar-Hari M, Annane D, Bauer M, Bellomo R, Bernard GR, Chiche JD, Coopersmith CM, Hotchkiss RS, Levy MM, Marshall JC, Martin GS, Opal SM, Rubenfeld GD, van der Poll T, Vincent JL, Angus DC. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016 Feb 23;315(8):801-10. doi: 10.1001/jama.2016.0287.
Shankar-Hari M, Phillips GS, Levy ML, Seymour CW, Liu VX, Deutschman CS, Angus DC, Rubenfeld GD, Singer M; Sepsis Definitions Task Force. Developing a New Definition and Assessing New Clinical Criteria for Septic Shock: For the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016 Feb 23;315(8):775-87. doi: 10.1001/jama.2016.0289.
Education Resources – Sepsis Trust
The Research of Predicting Septic Shock – International Emergency Medicine Education Project (iem-student.org)
Sepsis – International Emergency Medicine Education Project (iem-student.org)
Empiric Antibiotics for Sepsis in the ED Infographics – International Emergency Medicine Education Project (iem-student.org)
Sepsis – An Overview and Update – International Emergency Medicine Education Project (iem-student.org)

[cite]

Introduction

Performing a Rapid Triage Assessment

Performing a Focused History

Performing a Focused Physical Exam

Vital Signs and Objective Data

Heart Rate

Blood Pressure

Respiratory Rate

Oxygen Saturation

Temperature

Pain

Duration and Mechanism

Level of Consciousness

Triage Systems

Manchester Triage System

RED: Immediate/Life-Threatening

ORANGE: Emergent/Could Become Life-Threatening

YELLOW: Urgent/Not Life-Threatening

GREEN: Semi-Urgent/Not Life-Threatening

BLUE: Non-Urgent/Needs Treatment When Time Permits

Emergency Severity Index

Step-by-Step ESI Triage Algorithm

Types of Resources Defined by ESI

ESI Levels and Their Corresponding Urgency

Advanced Triage

Ordering an Initial Diagnostic Work-Up and Other Orders

Author

Priya Arumuganathan

Scott Walker Findley

Listen to the chapter

References

Reviewed and Edited By

Arif Alper Cevik, MD, FEMAT, FIFEM

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Orthopedic CDRs

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Case 1

Ottawa Ankle Rule

Ottawa Foot Rule

Ottawa Knee Rule

Case 1 Discussion

Trauma CDRs

Canadian Cervical Spine and NEXUS Rules

Case 2

Canadian C-spine Rule

NEXUS Criteria for C-spine Imaging

Case 2 Discussion

Canadian CT Head Rule and NEXUS Head CT Instrument

Case 3

Canadian CT Head Rule

NEXUS Head CT Instrument

Case 3 Discussion

PECARN Pediatric Head Trauma Algorithm

Case 4

PECARN Pediatric Head Trauma Algorithm

Age < 2

Age ≥ 2

Case 4 Discussion

PECARN Abdominal Trauma

NEXUS Chest Decision Instrument for Blunt Chest Trauma

Pulmonary CDRs

Case 5

Pulmonary Embolism Rule-Out Criteria (PERC)

Case 5 Discussion

Wells and Revised Geneva Score for Pulmonary Embolism (PE)

YEARS Algorithm for Pulmonary Embolism

Pneumonia Severity Index (PSI) Score

Ottawa COPD Risk Scale

Cardiac CDRs

Case 6

HEART Score for Cardiac Events

Case 6 Discussion

Emergency Department Assessment of Chest Pain Score (EDACS)

Ottawa Heart Failure Risk Score

Atrial Fibrillation – the CHA2DS2-VASc and HAS-BLED Scores

Abdominal CDRs

Gastrointestinal Bleeding

Case 7