The ABC Approach to the Critically Ill Patient

by Donna Venezia


History of the ABC’s

The basic ABC algorithm was initially designed and implemented on a large scale in the early 1960’s for those requiring cardiac-pulmonary resuscitation. The order has recently been changed to the CAB for those who have suffered a cardiac arrest (See BLS/ACLS – Cardiac Arrest section). Twenty years later the American College of Surgeons again modified this sequence for patients with acute traumatic injuries. Over the subsequent years, there have been many variations and modifications for the variety of critically ill patients presenting to an emergency department. Most recently, the addition of point-of-care testing with ultrasound has been incorporated into algorithms further to refine the accuracy of initial treatment in the critically ill.

Goals of approaching any critically ill patients are

  • Rapidly identify and manage life/brain-threatening conditions before the exact diagnosis is made.
  • After initial stabilization, follow with full history, exam, time-consuming lab/radiological testing and reach the final diagnosis.

Identifying A Critically Ill Patient

Triage is a reliable method to quickly select from a large group of waiting patients, those who may have a potential illness requiring time-critical management to save a life or the brain. As a standard structure, currently, all modern emergency departments have a triage unit to prioritize the patients. It aims to select more critical patients as early as possible and create an appropriate patient flow in the emergency department. However, triage can be done in the field by EMS staff, and patients may directly bring to the resuscitation room.

Potential critically ill patients may present with:

  • altered mental status (unresponsive or confused/agitated)
  • noisy respiration (gurgling, stidor, wheezing)
  • inability to speak normally (acute hoarseness or inability to articulate words)
  • respiratory distress (rapid/deep or slow/shallow/agonal respirations)
  • acute weakness or inability to ambulate (diffuse/focal muscle weakness or light-headedness/syncope)
  • acute torso discomfort (may be associated with radiation to jaw, anterior neck or shoulder/medial upper arms) suggestive of an MI/cardiovascular problem.
  • severe acute headache
  • intractable seizure (may not show muscular signs after a period of time)
  • history of significant trauma, drug ingestion, exposure, suicidal/homicidal ideation
  • significant vital signs abnormalities (age-dependent)

Point of Care Testing

  • adjunct tests/equipment that help guide early decision-making
  • results should be back within seconds to minutes, not hours!

The ABCDEF Sequence

  • Each letter represents a crucial body system that, if significantly disrupted and left untreated over hours rather than minutes, can result in death or brain damage.
  • The order is performed sequentially to avoid skipping crucial steps and generally to manage the most serious first, however, the sequence can and should be performed simultaneously (horizontal approach) in those with multiple life-threatening conditions if there are enough team members. Modify as appropriate to the individual.
  • Because management may need to be simultaneous, the team approach is crucial in successfully resuscitating any critically ill patient.
  • It is also important to emphasize that the availability of various treatment modalities at each medical facility.

Meaning of the letters in the ABCDEF sequence:

A = Airway Disorders with C-spine control

B = Breathing Disorders

C = Circulation/Cardiovascular Disorders

D = Disability (Neurological Disorders)

E = Exposure/Decontamination

F = Fever (Extreme Temperature Disorders)

How to approach the critically ill patient using the ABCDEF algorithm

For each letter or body system:

  • obtain a brief, focused history and exam
  • obtain available point-of-care testing to aid in the evaluation/management
  • initiate management for any acute life or brain threatening condition
  • then, proceed to the next letter and repeat
  • if no intervention is needed, quickly proceed through the sequence. (Evaluation of a normal person should take just a few minutes or even seconds.)

A – Airway with C-spine Control

  • Focused clinical assessment for impending/actual airway compromise:
    • noisy respirations (gurgling, stridor, choking sounds) with or without retractions
    • drooling, inability to swallow secretions, leaning forward in a tripod position
    • throat swelling sensation with or without pain
    • change in voice associated with symptoms of bacterial infection or allergy (hoarseness, “hot potato” voice)
    • active retching or vomiting with an inability to turn or move to protect from aspiration
    • oral exposure to fire/steam inhalation, chemicals, acids/alkali
    • neck trauma with crepitus over larynx or expanding hematoma
  • Point of Care Testing
    • generally, none required for complete obstruction
    • soft tissue neck X-ray (for potential/partial airway obstruction only)
    • indirect laryngoscopy (for potential/partial airway obstruction only)
    • fiberoptic laryngoscopy (for potential/partial airway obstruction only)
    • ultrasound (for identification of cricothyroid membrane or assessment proper endotracheal tube placement)
  • Emergency Equipment for Managing Airway Problems
  1. nasal or oral airway devices
  2. suction devices (rigid tip and/or small flexible tip)
  3. intubation equipment (i.e., laryngoscopes with ET tubes of various sizes)
  4. airway adjuncts for difficult airways – i.e. LMA, iGel, Bougie, video laryngoscope, fiberoptic laryngoscope, etc.
  5. Magill Forceps for foreign body removal
  6. Pre-intubation supplies – supplemental wall and/or tank oxygen, RSI medication, sedation medication, oral numbing medication
  7. “failed airway” kit – cricothyroidotomy kit with appropriate sized Shiley or endotracheal tubes
  8. capnography and/or ultrasound to assess for proper endotracheal tube placement
  9. appropriately sized cervical collars
  • Management Algorithm for Critical Airway Problems
    • possible c-spine injury – employ the second person to immobilize c-spine. Only jaw thrust maneuver is allowed in this situation (see caveat 1)
    • Tongue obstructs airway in an obtunded patient – perform either head tilt, chin lift, or use jaw thrust maneuvers if possible. See BLS/ACLS.
    • obtunded, without trauma – position patient on the side to avoid tongue obstruction
    • Patient unable to be positioned – place nasal or oral airway. Avoid oral airway if partially awake since may cause gagging/vomiting. Avoid nasal airway if midface trauma.
    • pharyngeal secretions, blood, and/or vomitus – suction
    • obstructing foreign body – perform abdominal thrusts/chest compressions per BLS or if visible, attempt to retrieve with McGill forceps.
    • laryngeal edema; likely anaphylaxis – administer IV/IM Epinephrine, likely hereditary angioedema – administer C1 esterase compound.
    • signs of imminent or complete airway obstruction, unrelieved from above – attempt intubation with the most appropriate device by the most experienced provider. May attempt BVM ventilation first, especially in children with epiglottis, as a temporizing measure.
    • unable to intubate or BVM – immediately perform cricothyroidotomy; avoid if laryngeal fracture a concern – prefer fiberoptic intubation or tracheostomy in OR if possible. (See cricothyroidotomy technique)
  • Caveats
    1. The airway is always associated with the phrase, “with c-spine control”. Before performing any airway procedures, one must quickly assess the likelihood of a c-spine injury. If there is a possibility of an injury in an unresponsive patient, i.e. found at the bottom of the stairs, or on the side of the road, unconscious, then assume an injury and protect the c-spine by simply immobilizing as best possible. Typically a C-collar is slid under the back of the neck while someone immobilizes the head. If airway management is required, the front of the collar can be opened or removed, as needed, while someone stabilizes the head in relation to the torso. Nothing further needs to be done in the primary survey to evaluate the c-spine.
    2. An unresponsive patient has a potential for airway compromise and subsequent aspiration. However, since proper intubation is time intensive, you may avoid intubation in these patients until the primary sequence is completed, unless the patient is actively retching. Have someone prepare the equipment as the sequence is being completed and continue the evaluation since treatment of a condition found later in the sequence may improve the mental status, making intubation unnecessary such as low blood sugar. Be prepared to log roll quickly if the patient vomits.
  • Conditions causing airway compromise
    • unresponsive patient with tongue blocking the airway an unresponsive patient who is unable to protect from aspiration of blood/vomitus, etc.
    • an unresponsive patient who is unable to protect from aspiration of blood/vomitus, etc.
    • infections, i.e. epiglottis, retropharyngeal abscess, etc.
    • allergic reactions/anaphylaxis, airway burns, i.e. steam, chemicals, alkali/acids, etc.
    • airway burns, i.e. steam, chemicals, alkali/acids, etc.
    • other causes of edema, i.e. ACE inhibitors, hereditary angioneurotic edema, laryngeal cartilage fractures secondary to trauma
    • laryngeal cartilage fractures secondary to trauma
    • expanding paratracheal hematoma
    • tracheomalacia
    • pharyngeal malignancies


B – Breathing Disorders

  • Focused clinical assessment for evidence respiratory failure
    • Cyanosis, inability to speak full sentences without needing a breath, confused/agitated or unresponsive with:
      1. Rate: too slow, shallow, agonal, gasping (age-dependent, generally rates <10 in an adult are abnormal)
      2. Rate: too fast and/or deep (again age-dependent but >20 in a resting adult is abnormal, and > 30 is significantly abnormal)
      3. Abnormal lung sounds:
        • unilateral decreased breath sounds (either dull or hyper-resonant)
        • wheezing or poor air movement
        • rales (fine crepitation) or rhonchi
      4. Chest wall abnormalities affecting breathing dynamics – flail chest/open punctures
    • Obtain as much focused history/exam as able to help define the need for a particular emergent treatment strategy for the common causes of critical respiratory conditions. For example, two common causes of severe respiratory distress are pulmonary edema and COPD. Both may present with wheezing (“cardiac asthma” in CHF), pedal edema and/or JVD, making the decision for which type of emergent management strategy difficult. Obtain as much focused history/exam in a brief period of time, i.e. family states heavy smoker with similar episodes in the past, all resolved with inhaler therapy or the patient has a history of recent ECHO with very poor ejection fraction, etc. to help make a decision about treatment.
    • If still not clear as to a management strategy, add point-of-care testing, i.e., lung sonography or upright portable CXR.
  • Point-of-Care testing
    • pulse Oximeter
    • C02 waveform monitor
    • arterial (ABG) or venous (VBG) blood gas
    • portable CXR (upright, if possible)
    • pulmonary ultrasonography:
      • evaluate lung sliding for pneumothorax
      • assess costophrenic angles for effusion/hemothorax
      • assess lung field segments for A/B lines, signs of consolidation
  • Management Algorithm for Acute Respiratory Disorders
    • fix all upper airway critical issues first
    • slow, agonal respirations or significant respiratory acidosis on ABG – provide BVM ventilation and administer Narcan.
    • rapid breathing with hypoxia – provide supplemental O2 by the non-rebreather mask to keep O2 saturation greater than 94%.
    • sucking chest wound – seal with an occlusive dressing (3 sides only)
    • tension pneumothorax – place a 14 gauge needle, immediately followed by a chest tube
    • massive hemothorax/pleural effusion – drain fluid, contact trauma surgeon since may need transfusion/transfer to OR for massive hemothorax
    • no improvement in oxygenation despite placement of non-rebreather mask or above procedures, either –
      • allow the patient to breathe spontaneously under tightly held BVM mask with PEEP valve on exhalation port and 15 L/min nasal cannula O2 placed under the mask
      • provide NIV (non-invasive ventilation) with CPAP/BiPAP
    • patient agitated and unable to tolerate masks – administer IV Ketamine.
    • Signs of obstructive pulmonary disease (COPD/asthma) – administer inhalational beta agonist. Consider additional therapy (i.e., ipratropium, Prednisone, Magnesium, epinephrine, etc.).
    • Signs of acute pulmonary edema with adequate BP – administer repetitive or continuous doses of Nitroglycerin SL, spray or IV. Consider additional drug therapy (i.e. Furosemide, etc.)
    • respiratory distress unresponsive to above therapy – intubate and mechanically ventilate
  • Emergency Equipment for Managing Breathing Emergencies
    1. Noninvasive ventilator NIV
    2. BVM (bag-valve-mask) with O2 supply and added PEEP valve
    3. additional wall or tank for an additional source of O2 (nasal cannula)
    4. 14 gauge catheter-over-the-needle
    5. various sized chest tubes
  • Caveats
    1. fast RR with clear lungs may be secondary to psychogenic hyperventilation, primary brain lesions, metabolic acidosis, poisoning, sepsis, pulmonary embolus or pericardial tamponade:
      1. consider paper bag breathing if O2 sats normal, no acidosis, and hyperventilation syndrome most likely (i.e., anxious with carpopedal spasm).
      2. Consider specific poisoning antidotes, i.e., cyanide antidote or hyperbaric/100% O2 for CO poisonings. See the toxicology section.
      3. Sepsis, Pulmonary embolus, and pericardial tamponade management are discussed in more depth in the circulatory section since the primary critical presentation is usually circulatory collapse.
      4. Obtain ABG/VBG if metabolic acidosis likely, manage most likely cause. See acid/base section.
    2. Severe hypoxia unresponsive to therapy, particularly with clear lungs, may be due to shunting from congenital heart disease which, in a neonate, may respond to the administration of PGE1 (prostaglandin).
    3. It is important to recognize that oxygenation and ventilation are different. A patient may not be hypoxic, especially if given supplemental O2 but may still be in acute ventilatory failure. (Only 250 cc of oxygen is used by the resting adult per minute. However, 6-10 L of air must be moved per minute to adequately ventilate a normal adult and prevent the rise in pCO2.)
  • Conditions Associated with Respiratory Failure
    • Pulmonary edema
    • COPD/asthma
    • severe pneumonia
    • ALI/ARDS from any cause (drugs, aspiration, etc.)
    • tension pneumothorax
    • chest wall dysfunction, (flail chest, muscular weakness, open sucking wound)
    • respiratory depressants (narcotic OD, sedative OD)
    • bronchiolitis
    • pulmonary embolus, air/amniotic fluid/fat embolus
    • massive hemothorax or massive pleural effusion
    • exhaustion from prolonged hyperventilation
    • chronic lung conditions: cancer, sarcoidosis, fibrosis, etc.


C – Circulation Disorders

Poor perfusion, Hypertensive crisis, Acute MI

  • Clinically assess for poor perfusion associated with
    • tachycardia: > 100 abnormal in adults, > 150 frequently clinically symptomatic.
    • bradycardia: < 60 abnormal, < 30 frequently clinically symptomatic.
    • hypotension: systolic < 90
    • Perfusion and cardiovascular assessment may include
      • Skin – i.e., cool, diaphoresis, pale, poor capillary refill, hives, erythema
      • Mental status changes – i.e., confusion, slow responses, agitation
      • Rhythm/quality of pulses in all four extremities
      • Assessment for hidden blood loss, i.e., rectal for melena, pelvic instability, pulsatile abdominal mass
      • history: internal/external bleeding/trauma, vomiting/diarrhea, oral intake/urine output, fever, diabetes/renal insufficiency/cardiac failure, medications, drug abuse/OD, last menses
  • Clinically assess for hypertension associated with
    • signs of end-organ damage/involvement, i.e., encephalopathy and/or papilledema, pulmonary edema, cardiac ischemia, renal impairment, and/or neurological abnormalities
    • pregnancy (generally 3rd trimester/first weeks postpartum); any new elevation of BP >140/90, particularly associated with a headache, abdominal pain, jaundice, shortness of breath and/or visual disturbances
  • Clinically assess torso discomfort for likely MI
    • description varies; besides chest discomfort, symptoms may include either/or epigastric discomfort, mid-back discomfort, radiation to shoulders, anterior neck, jaw or upper, inner arms.
    • Note: There are many serious causes of torso pain, i.e., simple pneumothorax, cholecystitis, pancreatitis, bowel perforation, etc.; work-up and management would be performed during the secondary evaluation unless there are signs or symptoms of circulatory collapse. The evaluation of torso discomfort in the initial assessment should an emergent EKG to pick up an MI.
  • Point-of-care testing
    • EKG (perform within 10 minutes of ED presentation; may include right-sided leads RV3,4 and posterior leads V8, V9)
    • Cardiovascular ultrasound to include assessment of:
      • LV cardiac contractility – normal, hyperactive, weak
      • the ratio of right to left ventricle size
      • pericardial fluid/tamponade physiology
      • aortic root dilation/dissection flap
      • IVC collapsibility with inspiration
      • evidence of free intraperitoneal fluid
      • evidence of abdominal aortic aneurysm and/or dissection
      • evidence of DVT in femoral veins
    • Telemetry monitor strip
    • ABG/VBG with electrolytes
    • Hemocult paper (only needed if any question of blood/melena in stools)
    • Urine beta-HCG for critical childbearing age females
  • Emergency Equipment for Managing Cardiovascular Emergencies
    1. pelvic binders/gauze for compression/tourniquets
    2. defibrillator/external pacemaker
    3. large bore IV’s and 0.9% saline or Ringer lactate fluids
    4. various sized IO insertion kits
    5. central line kits (only for large bore sheath placement, if necessary)
    6. thrombolytics or ability to access PCI (percutaneous coronary intervention) facility
    7. immediate access to O negative blood
    8. straight catheter/Foley catheter (for pregnancy check) and monitoring urine output
    9. Sengstaken-Blakemore tube
  • Management Algorithm for Critical Cardiovascular Disorders
    • Management of Poor Perfusion
      • place two large bore IV’s and attach telemetry monitor to all (may collect various labs including blood cultures, but should send type and crossmatch now)
      • evidence of external bleeding, unstable pelvis – apply pressure/ binder; in rare cases tourniquet
      • patient in the 3rd trimester of pregnancy – displace uterus to left/wedge under right flankunable to start IV – attempt IO (intraosseous) with 300 mmHg pressure cuff over the fluid bag to increase flow rate (Central line sheaths, if unable to start IO).
      • unable to start IV – attempt IO (intraosseous) with 300 mmHg pressure cuff over the fluid bag to increase flow rate (Central line sheaths, if unable to start IO).
      • if no evidence of cardiac failure – administer bolus 10-20cc/kg 0.9% NS/Ringers solution. (Further fluid administration determined by clinical/sono evaluation, risk/benefit, i.e., permissive hypotension and clinical response, i.e., urine output).
      • Evidence of unstoppable internal bleeding – immediate consultation with appropriate specialty, i.e., surgery, OB, GI, etc. Consider various meds to attenuate bleeding, i.e., Tranexamic Acid, Terlipressin for esophageal bleed or Oxytocin for OB bleed. Consider various procedures to stop internal bleeding, i.e., Sengstaken-Blakemore tube placement for esophageal bleed, uterine massage post-delivery, etc.
      • severe blood loss and/or persistent unstoppable bleeding – transfuse O-negative units until type specific or fully cross-matched blood available
      • unstable tachydysrhythmia (not sinus, multifocal atrial tachycardia, junctional) – cardiovert per ACLS
      • unstable bradydysrhythmia – administer meds (i.e., Atropine, etc.)/place external pacemaker per ACLS
      • evidence of rhythm disorder is associated with K+ abnormality by the lab, clinical history (i.e., renal failure, DM) and/or EKG findings – administer appropriate hyper/hypokalemia/magnesemia therapy
      • dysrhythmia unresponsive, with evidence of thyroid storm or history of drug OD, consider thyroid management or specific antidotes: NaHCO2 for fast Na+ channel OD (TCA, tricyclic antidepressants), Digibind for Digoxin toxicity, etc.
      • evidence of aortic dissection by clinical, sono evaluation – administer b-blocker first, i.e., Esmolol, then antihypertensive, i.e., Nitroprusside, contact cardiovascular surgery
      • evidence of obstructive shock by clinical/sono – treat appropriately as guided by diagnosis, i.e., thrombolytics/interventional radiology for pulmonary embolus, pericardiocentesis for tamponade, chest tube for tension pneumothorax, etc.
      • no evidence of acute volume loss and/or no response to fluids or previous therapies – start pressors, Norepinephrine, Dopamine, Epinephrine, Dobutamine, etc., i.e., Epi for anaphylaxis, Dob/Norepi for cardiogenic shock, Norepi for sepsis, etc.
      • if no response to above, consider either:
        1. adrenal crisis – start IV Hydrocortisone. (Dexamethasone, if choose to perform testing concurrently.) and/or
        2. drug OD (i.e., b-blocker or calcium channel blocker – treat with high dose Insulin/glucose)
  • Management Algorithm for Severe Hypertension associated with
    • evidence of end-organ damage (ischemia, heart failure, encephalopathy, etc.) – administer IV antihypertensive (Labetalol, Nitroprusside, etc.) Avoid pure beta blockers if suspect cocaine overdose.
    • evidence of hemorrhagic stroke, thrombotic stroke, subarachnoid hemorrhage (See Disability Section)
    • pregnancy and new elevation of BP >140/90 – re-evaluate in 15 minutes
    • pregnancy with evidence of pre-eclampsia/eclampsia (i.e., headache, nausea/vomiting, abdominal pain, visual disturbances, shortness of breath, hyperreflexia, seizures – with or without proteinuria) – or severe hypertension BP 160/110 – administer MgSO4 and initiate antihypertensive, (i.e., Hydralazine, Labetalol, or Nifedipine), immediate OB consult.
  • Management Algorithm for Torso Discomfort
    • acute torso discomfort with MI documented by EKG – contact cardiology for immediate PCI/transfer and/or administer thrombolytics depending on location and timing of event per ACLS
    • acute MI by EKG (whether eligible or not for PCI/thrombolytics) – monitor for dysrhythmia, i.e., ventricular fibrillation, etc., administer Aspirin, follow protocols per local cardiologist.
    • high suspicion of cardiac ischemia but EKG not diagnostic – repeat in 10-15 minutes.
  • Causes of critical cardiovascular conditions
    • dehydration
    • acute blood loss (internal and external)
    • sepsis
    • drug toxicity/OD
    • cardiogenic shock
    • anaphylaxis
    • neurogenic shock
    • adrenal crisis
    • thyroid storm
    • obstructive shock
      • pulmonary embolus
      • pericardial tamponade
      • tension pneumothorax
      • gravid uterus compressing IVC
    • tachydysrhytmias/bradydysrhythmias with or without electrolye disorders
    • symptomatic hypertensive with or without pregnancy
    • acute MI
    • acute aortic dissection/rupture


D – Disability (Neurological/Psychological Disorders)

  • Clinically assess for
    • depressed consciousness (lethargic, confused, comatose) (may use GCS to assess the degree of unresponsiveness)
    • pupil size, symmetry, and reactivity
    • agitation, delirium (waxing and waning level of consciousness associated with confusion/disorientation and/or hallucinations – typically, visual/tactile)
    • acute focal weakness/paralysis, or inability to speak
    • severe, acute headache, nuchal rigidity
    • signs of status epilepticus, including subtle seizure-like activity (i.e., twitching eyelids, stiffness, persistent unresponsiveness after obvious seizure-like activity)
    • acute psychiatric disorder with either suicidal or homicidal ideation
  • Point-of-Care Adjuncts
    • fingerstick glucose measurement
    • non-contrast head CT to be performed in less than 30 minutes
    • acute malaria screen in appropriate environments
    • rapid HIV test
    • electrolytes (Na+, and Ca++, in particular), if available, on ABG/VBG assessment, sono for evaluation of papilledema
    • sono for evaluation of papilledema
  • Emergency Equipment Needed for Neurological Management
    1. CT scanner
    2. access or ability to transfer to neurosurgical equipped OR
    3. LP tray
    4. leather restraints
    5. stretchers that allow for head elevation
  • Management Algorithm for Critical Neurological Disorders
    • Acute Agitation/Delirium Algorithm
      • in all patients attempt to talk first to calm and remove anything that might cause injury
      • agitation, particularly in young patients or possible drug toxicity/withdrawal – administer Benzodiazepines. Avoid in elderly with dementia; likely to increase confusion. Monitor respirations in all.
      • agitation, with signs of hypoxia, hypoperfusion – consider Ketamine starting dose 1mg/kg with continued ABC resuscitation
      • agitation, with a known history of psychiatric disorder or likely new-onset psychiatric disease – administer psychotropic agent, i.e., Haldol IV, IM. with or without Benzodiazepine.
      • agitation, unable to calm with above and/or patient an imminent danger to self/others – call for ‘man-power’ support and apply four-point restraints. (Provide close monitoring of the patient and remove restraints as soon as deemed safe)
    • Acute Mental Status Depression Algorithm
      • fix the airway, breathing and circulation conditions first
      • Check fingerstick glucose – if low administer bolus or drip of D50/D25 or D10 depending on patient age. May give IM Glucagon if unable to start IV and patient cannot swallow. Administer Thiamine with the glucose. (Narcan should have already been given under section B).
      • if GCS < 9 after ABC resuscitation – the patient likely requires intubation to protect from aspiration – prepare equipment
      • History acute fever, headache, without focal neurological signs, recent seizure history or impaired immunity and exam/sono shows no papilledema – check malaria smear, rapid HIV test, perform LP, initiate empiric antibiotic treatment (possible steroids first), based on age/likely etiology. Before any meds given attempt to quickly determine if allergic, from family, old records, etc.
      • History acute fever, headache, with focal neurological signs or seizures, impaired immunity and/or exam/sono shows papilledema – do not perform immediate LP – check malaria smear, rapid HIV test, initiate empiric antibiotic treatment (possible steroids first), based on age/likely etiology. Before any meds given, attempt to determine if allergic, from family, old records, etc. Follow with CT and possible LP, ASAP.
      • consider status epilepticus in all non-responsive patients, (motor signs may be minimal) or if not awakening between seizures:
        • check electrolytes – if hyponatremic administer 2cc/kg over 10 min of 3% NaCl (max 100cc)
        • Third trimester/post delivery – administer MgSO4/consult OB
        • likely INH OD or neonatal dependency – administer Pyridoxine.
        • all others – start with Benzodiazepines, consult neurology
      • if no improvement with above – obtain head CT; follow management in the section below.
  • Focal Neurological Signs/AMS (with or without head trauma) and/or a Sudden, Severe Headache Algorithm
    • obtain a head CT in all patients, if available
    • normal CT, likely SAH by history (onset > 6 hours), perform LP – nontraumatic blood/ xanthochromia, immediate neurosurgery consultation, control BP < 160/90. See SAH guidelines.
    • Normal CT, likely thrombotic stroke – initiate TPA/endovascular therapy per protocols, control BP to <185/110. If unable to use TPA, do not drop BP unless >220/120. See thrombotic stroke guidelines.
    • New intra-cerebral bleed on CT – control BP to <140/90; reverse anticoagulants. See hemorrhagic stroke guidelines.
    • epidural/subdural/nontraumatic SAH on CT – immediate neurosurgery consultation for possible OR/IR intervention.
    • Evidence of acute herniation – raise the head of bed 30-45 degrees (assuming no spine trauma), consider Mannitol, 3% NS, and/or mild, brief hyperventilation. Consider IV dexamethasone for a tumor with herniation.
  • Causes of critical neurological disorders
    • conditions affecting airway, breathing and/or circulation
    • metabolic disorders:
      • Hypoglycemia/hyperosmolar coma/DKA
      • thyroid disorders
      • electrolyte disorders (primarily Na+ and Ca++)
      • liver/kidney failure, etc.
    • drug toxicity/OD or drug withdrawal syndromes
    • acute psychiatric disorders
    • mass lesions (hemorrhage, tumors, abscesses)
    • infections – meningitis/encephalitis (bacterial, fungal, viral, parasitic infections including cerebral malaria)
    • status epilepticus and post-ictal states
    • stroke syndromes – thrombotic, intracerebral hemorrhagic, SAH


E – Exposure

  • Clinically evaluate
    • areas hidden by clothing/body position for missed lesions (rashes/stab/gunshot wounds) by undressing and log rolling.
    • the body for evidence of self/child/elder/domestic abuse and evidence of IV drug abuse.
    • for possible contaminated clothing/skin: substances absorbed through the skin (i.e., hydrocarbon pesticides), caustics, radiation or objects causing continued burns, etc.
  • Point-of-care testing
    • none
  • Management Algorithm for Exposure Disorders
    • signs of child or self-abuse – provide safe location and separate from abusers
    • evidence of hidden bleeding – manage as per Section C
    • evidence of clothes/skin contamination – decontaminate, according to toxicity and protect self and others in the process (self-protection should be implemented at the onset of patient evaluation)
    • re-dress patient in a gown to prevent cooling and provide privacy
  • Equipment Needed for Exposure/Decontamination
    1. shower with containment for water runoff
    2. protective gowns, masks, gloves for staff
    3. isolation room with air vent containment
    4. shears/metal cutter


F – Fever (Extreme Temperature Disorders)

  • Clinically Assess
    • skin warmth/coolness
    • skin color (pale/red), dryness, diaphoresis
    • muscle rigidity, shivering
    • thyroid for nodules/enlargement
    • obtain the history of medications (recent psychotropic/succinylcholine, anesthetics, etc.), drug abuse, endocrine disease, outdoor exposure, excessive exercise
  • Note: normal temperature is 98.6 F or 37 C. Any temperature above 100.4 F or 38 C rectally is considered a fever. However, it is the extremes of temperature that require emergent management, usually > 105 F (40.5 C) or < 95 F (35 C)
  • Point-of-care testing
    • Thermometer: oral -affected by mouth breathing, drinking warm/cold fluids
      • axillary – add a point to correlate with rectal temperature.
      • rectal – most accurately reflects core temperature.
  • Emergency Equipment Required
    1. fan
    2. ice packs
    3. lavage tubes
    4. warning blankets
    5. rectal temperature probe
  • Management Algorithm for Critical Temperature Extremes
    • Hyperthermia Algorithm
      • initiate heat loss for all by
        • convection (evaporation) methods, i.e., tepid water spray on skin and fan and/or
        • conduction heat loss by placing ices packs over major vessels, i.e., groin, axilla or neck. (Ice tub immersion possible, but not able to easily monitor.)
        • cool IV fluids
      • if severe temperature elevations – initiate core cooling: ice water lavage of the bladder, thorax, stomach and prevent shivering with drugs such as dexmedetomidine / Butorphanol.
      • evidence of anticholinergic, sympathomimetic, MAOI poisoning – consider antidotes.
      • evidence of neuroleptic malignant syndrome – stop neuroleptics, consider various antidotes See management of neuroleptic malignant syndrome.
      • evidence for thyroid storm – initiate b-blockade, cortisone, PTU, then iodine last
  • Hypothermia Algorithm
    • mild to moderate temperature decline – 30-35 degrees – external rewarm, i.e., blankets and initiate warmed IV fluids, and heated inspired air heated to 45 degrees
    • severe, <30 degrees – consider additional core rewarming, i.e., peritoneal lavage, thoracic lavage, esophageal tubes, etc.
    • evidence of myxedema coma – administer thyroxine and hydrocortisone, avoid rapid rewarming
  • Causes of critical heat/cold related conditions
    • exposure to extreme environmental temperature conditions
    • endocrine disorders (especially hyper/hypothyroidism)
    • toxins/OD’s (anticholinergics, sympathomimetic, MAOI drugs, ASA, etc.)
    • sepsis (for both extremes)
    • neuroleptic malignant syndrome
    • malignant hyperthermia associated with anesthetics

After the sequence is completed, quickly re-evaluate the patient to see if intervention(s) resulted in improvement.

Then follow the ABC’s with:

  • evaluation of past medical history, medication history, and allergy history, if not already performed
  • perform the secondary survey (i.e., detailed history and a complete exam)


References and Further Reading