Hyperkalemia (2024)

November 14, 2024November 26, 2024 ~ iEM Education Project Team ~ Leave a comment

by Chelsea N. Allen

You have a new patient!

A 58-year-old female is brought into the emergency department (ED) by her family for dizziness and fatigue that started today. She has a history of hypertension for which she takes a calcium channel blocker and end-stage renal disease (ESRD) and has been on dialysis for the last four years. She did miss her dialysis session today due to her symptoms, with her last session four days ago.

At triage, her vital signs are as follows: BP 170/90 mmHg, HR 30/min, RR of 18/min, temperature 37.1 degrees Celsius, SpO2 of 98% on room air. She appears fatigued but is able to answer questions appropriately and has no obvious focal neurologic deficits.

Triage EKG is below

What do you need to know?

Hyperkalemia is one of the most important electrolyte abnormalities you will encounter in the emergency department (ED), given the potential for cardiac arrest in these patients. It refers to when the serum potassium (K) is greater than 5.5mEq/L. In all patients suspected of hyperkalemia, it is essential to place them on a cardiac monitor, obtain IV access, and perform an EKG due to the significant role potassium plays in the cardiac cycle. These patients may have non-specific symptoms, such as weakness and fatigue, and thus can make it hard to discern the diagnosis up front. Patients with a high pretest probability, such as those who miss dialysis or have had prior episodes of hyperkalemia, are usually treated for hyperkalemia before lab results are available due to the potential life-threatening nature of the condition. Potassium is stored in the body’s cells. It can be excreted during cellular damage, such as in rhabdomyolysis, or during certain physiologic states to balance the body’s pH when the serum becomes acidotic (e.g., DKA) [1,2]. Potassium is then excreted from the body by the kidneys/urinary system, so in patients whose kidney function has declined, such as ESRD, or in patients with an obstruction (bladder stone, enlarged prostate), potassium must be excreted through dialysis or by removal.

Medical History

Patients with hyperkalemia often present with non-specific symptoms, such as fatigue, muscle weakness, and cramps, which can often lead to a delay in the diagnosis and can be detrimental, even fatal to the patient. Elevations of potassium in a patient’s serum can be caused when there is a disruption in the storage or excretion mechanisms in the body and can cause cardiac arrhythmias, such as premature beats (PVCs), irregular beats (atrial fibrillation) or cardiac arrest (ventricular fibrillation) due to the role of potassium in regulating the cardiac membrane potential [1-5]. Since an underlying elevation in potassium can cause these non-specific symptoms, it is imperative to do a thorough history, keying in on a history of kidney issues, dialysis appointments, and urinary symptoms.

Physical Examination

The most crucial physical exam components in patients with hyperkalemia are the cardiac and skin exam, especially in patients who may not be able to give you much information, as a thorough skin exam can elicit an AV fistula/graft or tunnel catheter, which would clue you into the patient being on dialysis. If the patient does not have a history of ESRD on dialysis, the cardiac exam could be another clue, elucidating irregular rhythms or bradycardia and prompting you to get further evaluation with an EKG.

Alternative & Differential Diagnoses

Given that hyperkalemia can cause a myriad of non-specific symptoms, patients can sometimes have a long list of differential diagnoses. Outside of the cardiac complications, hyperkalemia can cause muscle cramping, fatigue, or feeling weak. Unless you have a high index of suspicion, these symptoms can be attributed to muscle strains or viral illnesses, which in patients who are otherwise healthy or have a good history of these may be more likely than hyperkalemia [5].

Acing Diagnostic Testing

One of the most important tests for patients suspected of having hyperkalemia is the EKG, given how quickly this bedside test can be performed and the wealth of information that can be obtained, especially regarding electrolytes [4,5]. The classic EKG finding in patients with hyperkalemia is peaked T waves. However, hyperkalemia can mimic many EKG changes, and other findings suggest hyperkalemia are a widened QRS, flattened P waves, and heart blocks [3,4,5]. The EKG may follow a step-wise pattern of peaked T waves, followed by progressively lengthening QRS. However, generally, they do not always follow this pattern, so it is important to have a high index of suspicion when you see these changes. The next step is usually laboratory testing with a basic metabolic panel to confirm hyperkalemia. It can also indicate the patient’s electrolyte levels, provide insight into their acid-base balance, and suggest other potential diagnoses. You may also get other testing depending on the cause of the hyperkalemia, such as CT or US imaging, if urinary tract obstruction is the suspected cause. However, in general, imaging is not needed to make the diagnosis.

Risk Stratification

Most of the patients with hyperkalemia are going to be chronic kidney disease or dialysis patients, which are inherently at higher risk given their underlying disease process as well as the fact that the kidneys process and excrete potassium in the body. Specifically, anuric patients within this group are going to be at higher risk for complications, given that the only way to excrete potassium is through dialysis, putting them at risk for the potentially fatal complications of hyperkalemia [1,2].

Management

As always, following the ABCs of emergent patient management is crucial in deciding how quickly you need to intervene, especially in hyperkalemic patients, where cardiac arrest is a high possibility. Once you have assessed that your patient has a patent airway by speaking to them, their breathing by listening for bilateral breath sounds, and their circulation by ensuring they have a pulse, the next critical step in managing hyperkalemia is the reduction of potassium within the body and serum. This is achieved in two ways: shifting and elimination [2,3,4,5]. One medication we use in hyperkalemia where we have EKG changes attributed to elevations in potassium is Calcium (gluconate or chloride) which the sole purpose of this medication is stabilization of the cardiac membrane to prevent further deterioration into unstable rhythms and is usually given first in the line of medications [2]. Its onset is rapid (15-30 min) with a duration of 30-60 min. Monitor closely as it does not lower potassium but rather protects the heart. Calcium chloride is more concentrated than calcium gluconate, so it requires a central line due to the risk of tissue damage.

Shifting medications will be Insulin and Albuterol, given that these medications work in the cAMP pathway on the cell membranes, causing extracellular potassium to shift intracellularly, thereby transiently decreasing serum potassium. Dextrose is usually given with insulin to prevent the drop in glucose associated with insulin use, and it does not shift/eliminate potassium, but it is still vital. If your patient is able to make urine, giving a dose of Furosemide (or another potassium-depleting diuretic) is useful to help start the process of potassium elimination, as these medications will pull extracellular potassium into the waste product (urine). If your patient is unable to make urine, giving Sodium zirconium cyclosilicate, a potassium binder in your gastrointestinal tract, to help eliminate potassium is another way to help deplete body potassium. If severe enough (e.g., arrhythmias/cardiac arrests, ESRD patients), most patients will need to undergo hemodialysis for definitive treatment/removal of potassium. Listed below are the medications mentioned above, as well as the recommended doses and frequency.

Table: Medications frequently used in hyperkalemia treatment [5,6]

Drug generic Name	Dose	Effect	Duration	Pregnancy	Cautions / Comments
Calcium gluconate	1-3gm IV	15-30min	30-60min	C, only if clearly needed
Calcium chloride	1gm IV	15-30min	30-60min	C, only if clearly needed	Concentrated Calcium, needs central line
Albuterol	15-20mg nebulized	30min	2hrs	C
Insulin/Dextrose	10u Regular insulin IV; 25-50gm of 50% dextrose IV	30min-45min	3-6hrs	B (insulin); C (dextrose)	Usually given together, but can be omitted if Glucose >300
Furosemide	40-80mg IV	15-20min	2hrs	C
Sodium zirconium cyclosilicate	10mg TID PO	Can take up to 48hrs		Not Assigned	Usually not first line in the ED

Special Patient Groups

Given its life-threatening nature, hyperkalemia is generally treated the same way in all patient populations, including children and pregnant patients [5]. The above medications are all for adults, but they do have weight-based dosing for pediatric patients that is easily accessible on Broselow tapes found in the Emergency Department. Additional considerations for each group as follows;

Pediatrics

Hyperkalemia in children is often linked to kidney insufficiency, acidosis, and certain genetic conditions affecting potassium balance [7]. Pediatric hyperkalemia treatment includes insulin-glucose therapy, calcium gluconate, and sometimes sodium bicarbonate for acidosis [7]. Dosing is weight-based; careful monitoring is essential to prevent hypoglycemia following insulin administration [7].

Geriatrics

Older adults are prone to hyperkalemia due to decreased renal function and polypharmacy, especially with medications like ACE inhibitors and potassium-sparing diuretics [8]. Geriatric patients require slower dose titration and close monitoring of cardiac function. Reducing or discontinuing potassium-elevating medications may be prioritized before more invasive treatments. Assessing patient’s medication profile carefully to minimize potential interactions and electrolyte disturbances is important.

Pregnant Patients

Hyperkalemia is rare in pregnancy but may occur due to conditions like preeclampsia or excessive potassium supplementation. Treatment is similar to that of the general population but focuses on the safety of both the mother and fetus. Agents like insulin-glucose therapy are used with caution, and glucose and potassium levels are monitored closely to avoid fetal complications.

Caution!

The drugs listed in the table do have specific considerations for pediatric, geriatric, and pregnant patients, as follows:

Calcium Gluconate and Calcium Chloride:
- Pregnant Patients: Generally considered safe for use when needed (Pregnancy Category C), but only administered if benefits outweigh the risks due to limited data on safety in pregnancy.
- Pediatrics: Dosing is usually adjusted based on weight, and administration must be done with caution due to the risk of tissue necrosis with calcium chloride if extravasation occurs.
Albuterol:
- Pregnant Patients: Classified as Category C. Used in asthma or bronchospasm, but risks must be considered, as inhaled bronchodilators are typically preferred.
- Pediatrics and Geriatrics: Pediatric dosing is weight-based, while elderly patients may require lower doses due to sensitivity to stimulants.
Insulin/Dextrose:
- Pregnancy: Insulin is preferred for managing blood glucose in pregnant women with diabetes, categorized as B for insulin, while dextrose is safe when needed.
- Pediatrics: Used in hyperkalemia or diabetic ketoacidosis with dose adjustments based on age and weight.
Furosemide:
- Geriatrics: Lower doses are generally recommended due to increased risk of dehydration and electrolyte imbalance.
- Pregnancy: Considered Category C, used only if necessary as it may affect fetal renal development.
Sodium Zirconium Cyclosilicate:
- Limited data on its use in pediatric and pregnant populations, and generally not a first-line treatment in the emergency department for these groups.

Infographic

When To Admit This Patient

There are very few instances where hyperkalemic patients will be discharged from the ED, given the potential life-threatening arrhythmias. However, ESRD patients who receive dialysis, are back to their baseline and have to follow up/able to make it to their scheduled dialysis sessions will most likely be able to be discharged if a cause for their hyperkalemia is something simple, such as missed dialysis appointments. Ensure clear, specific follow-up arrangements to minimize recurrence risk. Confirm with her dialysis provider for her next sessions. Most other patients will be admitted for monitoring to ensure their potassium levels are normalizing and to identify a cause.

Revisiting Your Patient

As you recall, we had a 58-year-old female with dizziness/fatigue who had missed her dialysis session and was found to be bradycardic and hyperkalemic on her initial workup. She was initially treated with calcium gluconate with improvement in her EKG as well as her symptoms and was able to receive dialysis in the ED. After a brief period of observation after her dialysis sessions and repeat BMP showing normalization of her potassium, she was discharged home with her family to continue her outpatient dialysis schedule.

Author

Chelsea N. Allen, DO

Originally from Adel, GA, USA, graduated college with a degree in biology from Columbus State University in Columbus, GA, USA. Then attended medical school at the Edward Via College of Osteopathic Medicine in Auburn, AL before completing her emergency Medicine residency at the University of Florida, Jacksonville, in Jacksonville, FL, USA. She is currently the Assistant Program Director for the Emergency Medicine program at UF-Jacksonville as well.

Listen to the chapter

References

Harris AN, Grimm PR, Lee HW, et al. Mechanism of Hyperkalemia-Induced Metabolic Acidosis. Journal of the American Society of Nephrology. 2018;29(5):1411-1425. doi:https://doi.org/10.1681/ASN.2017111163
Mount D. Potassium balance in acid-base disorders. Accessed: November 14, 2024. https://www.uptodate.com/contents/potassium-balance-in-acid-base-disorders.
Lindner G, Burdmann EA, Clase CM, et al. Acute hyperkalemia in the emergency department: a summary from a Kidney Disease: Improving Global Outcomes conference. Eur J Emerg Med. 2020;27(5):329-337. doi:10.1097/MEJ.0000000000000691
Helman, A, Baimel, M, Etchells, E. Emergency Management of Hyperkalemia. Emergency Medicine Cases. September, 2016. Accessed November 14, 2024. https://emergencymedicinecases.com/alcohol-withdrawal-delirium-tremens/
Wachira BW. Fluids, Electrolytes, and Acid-Base Disorders. In: Cydulka RK, Fitch MT, Joing SA, Wang VJ, Cline DM, Ma O. eds. Tintinalli’s Emergency Medicine Manual, 8e. McGraw-Hill Education; 2017. Accessed November 14, 2024. https://accessemergencymedicine-mhmedical-com.uaeu.idm.oclc.org/content.aspx?bookid=2158&sectionid=162269029
Rafique Z, Peacock F, Armstead T, et al. Hyperkalemia management in the emergency department: An expert panel consensus. J Am Coll Emerg Physicians Open. 2021;2(5):e12572. Published 2021 Oct 1. doi:10.1002/emp2.12572
Lederer Hyperkalemia. Accessed: November 14, 2024. https://emedicine.medscape.com/article/240903-overview?form=fpf
Ortiz A, Galán CDA, Carlos Fernández-García J, et al. Consensus document on the management of hyperkalemia. Nefrologia (Engl Ed). 2023;43(6):765-782. doi:10.1016/j.nefroe.2023.12.002

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.

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

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Acute Atrial Fibrillation in the ED: Almost all goes home

September 13, 2021August 23, 2021 ~ Israa M Salih, UAE ~ Leave a comment

Atrial fibrillation (AF) is the most common dysrhythmia presenting to ED. The management options depend on patient stability, presence of underlying causes and factors in the patient history. In stable patients presenting in AF with a rapid ventricular response, both rate and rhythm control are acceptable approaches. Physicians often tend toward rate control because evidence has shown no mortality benefit between the two approaches. The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) trial contributed to this trend when it concluded no survival advantage and higher risk of adverse drug effects with rhythm control. However, rhythm control is the preferred approach for the management of acute stable AF in Canadian guidelines. The advantages are a higher rate of symptom resolution, restoration of sinus rhythm and avoiding the need for rate control prescriptions, decreased ED length of stay, and hospital admissions.

In the electrical versus pharmacological cardioversion for emergency department patients with acute atrial fibrillation (RAFF2) trial, it was found that both drug–shock and shock-only strategies were effective, rapid, and safe with 96% of patients discharged home in sinus rhythm. The drug infusion worked for 50% of patients avoiding procedural sedation.

The evidence that supports the management of acute AF in the ED without hospital admission is increasing. Implementing practices to achieve that will markedly decrease the burden on the health care system.

ED Management

Approach of Atrial fibrillation

AF might be secondary to variable causes, including ACS, Heart failure, PE, sepsis and bleeding. In patients with secondary AF, cardioversion might be harmful, and the mainstay of treatment is tackling the underlying cause. Those patients will require hospital admission. For primary AF, if the patient is unstable, electrical cardioversion should be done without delay. Stable primary AF may be managed with rate or rhythm control.

Rate control can be achieved with the following:

CCB: Diltiazim 0.25 mg/kg over ten mins, repeat q15-20 mins, up to three doses (avoid in heart failure)

BB: Metoprolol 2.5-5 mg q15-20 mins

Digoxin: 0.25-0.5 mg loading dose then 0.25 mg q4-6 hs (if hypotension or acute HF occur)

Target is HR <100 at rest or <110 walking

Rhythm control is safe with the following according to The CAEP AF best practice guidelines:

Anticoagulated for three or more weeks.
No valvular heart disease, prior stroke or TIA plus:

Onset in 12 hours or less
Onset more than 12 hours but less than 48 hours plus less than two of :
- Age less than 65, DM, HTN, HF.
Cleared by TOE

Methods:

Procainamide 15mg/kg in 500 ml of NS over an hour.

Other agents: Amiodarone, Ibutilide, flecainide, etc.

Electrical: 150-200 J synchronized. Requires sedation.

Anticoagulation:

If CHADS positive then discharge on DOAC or Warfarin.

Disposition:

Almost all patients can be discharged home after cardioversion or effective rate control with appropriate follow up: within a week if warfarin or rate control agent prescribed, otherwise in 4 weeks.

Patients will require admission if one of the following:

Highly symptomatic after treatment.
ACS
Acute heart failure not improved in the ED

References and Further Reading

Stiell, I. G., Macle, L., & CCS Atrial Fibrillation Guidelines Committee (2011). Canadian Cardiovascular Society atrial fibrillation guidelines 2010: management of recent-onset atrial fibrillation and flutter in the emergency department. The Canadian journal of cardiology, 27(1), 38–46. https://doi.org/10.1016/j.cjca.2010.11.014
Wyse, D. G., Waldo, A. L., DiMarco, J. P., Domanski, M. J., Rosenberg, Y., Schron, E. B., Kellen, J. C., Greene, H. L., Mickel, M. C., Dalquist, J. E., Corley, S. D., & Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) Investigators (2002). A comparison of rate control and rhythm control in patients with atrial fibrillation. The New England journal of medicine, 347(23), 1825–1833. https://doi.org/10.1056/NEJMoa021328
Baymon, D. E., & Baugh, C. E. (2020). Patients with Atrial Fibrillation in the Emergency Department: Strategies to Achieve Best Outcomes. https://www.hmpgloballearningnetwork.com/site/eplab/patients-atrial-fibrillation-emergency-department-strategies-achieve-best-outcomes
Martín, A., Coll-Vinent, B., Suero, C., Fernández-Simón, A., Sánchez, J., Varona, M., Cancio, M., Sánchez, S., Carbajosa, J., Malagón, F., Montull, E., Del Arco, C., & HERMES-AF investigators (2019). Benefits of Rhythm Control and Rate Control in Recent-onset Atrial Fibrillation: The HERMES-AF Study. Academic emergency medicine : official journal of the Society for Academic Emergency Medicine, 26(9), 1034–1043. https://doi.org/10.1111/acem.13703
Stiell, I. G., Sivilotti, M., Taljaard, M., Birnie, D., Vadeboncoeur, A., Hohl, C. M., McRae, A. D., Rowe, B. H., Brison, R. J., Thiruganasambandamoorthy, V., Macle, L., Borgundvaag, B., Morris, J., Mercier, E., Clement, C. M., Brinkhurst, J., Sheehan, C., Brown, E., Nemnom, M. J., Wells, G. A., … Perry, J. J. (2020). Electrical versus pharmacological cardioversion for emergency department patients with acute atrial fibrillation (RAFF2): a partial factorial randomised trial. Lancet (London, England), 395(10221), 339–349. https://doi.org/10.1016/S0140-6736(19)32994-0
Ian G. Stiell, et al. (2021). 2021 CAEP Acute Atrial Fibrillation/Flutter Best Practices Checklist.https://caep.ca/wp-content/uploads/2021/06/2021-CAEP-AAF-Checklist-FINAL-6-June-2021.pdf

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Defibrillator: Clear!

August 9, 2021August 9, 2021 ~ Jule Santos, Brasil ~ Leave a comment

So, this is your first day at your internship rotation in the Emergency Department. You see some movement in the resuscitation room, and someone shouts: CODE!

Then, you approach the team, excited to learn and help with cardiopulmonary resuscitation (CPR). The attending physician looks at you and asks: Do you know how to use the defibrillator?

What would your answer be?

Knowing the main functions of the defibrillator is essential but not enough; you need to get used to the model in your hospital to be able to help safely with an emergency.

Defibrillators are devices used to apply electrical energy manually or automatically. Their use is indicated for electrical cardioversion, defibrillation or as a transcutaneous pacemaker.

Later that day, another patient presents with unstable atrial fibrillation (AFib).

The attending suggests cardioverting the patient. Do you know how to prepare the defibrillator?

Defibrillation versus cardioversion

Both defibrillation and cardioversion are techniques in which an electrical current is applied to the patient, through a defibrillator, to reverse a cardiac arrhythmia.

Defibrillation

Defibrillation is a non-synchronized electrical discharge applied to the chest, which aims to depolarize all myocardial muscle fibres, thus literally restarting the heart, allowing the sinoatrial node to resume the generation and control of the heart rhythm, and reversing the severe arrhythmias. It is indicated for pulseless ventricular tachycardia and ventricular fibrillation during CPR.

Electrical Cardioversion

Electrical cardioversion is the application of shock in a synchronized way to ensure the electric discharge is released in the R wave, that is, in the refractory period because accidental delivery of the shock during the vulnerable period, that is, the T wave, can trigger VF. It is reserved for severe arrhythmias in unstable patients with a pulse. It can usually be an elective procedure.

Special Situations

Digital Intoxication

Digital intoxication can present with any type of tachyarrhythmia or bradyarrhythmia. Cardioversion in this situation is a relative contraindication, as digital makes the heart sensitive to electrical stimulation. Before considering cardioversion, correct all electrolyte imbalances, otherwise, the cardioversion can degenerate the rhythm to a VF.

Pacemaker / Implantable cardioverter-defibrillator (ICD)

Cardioversion can be performed, but with care. The inadequate technique can damage the generator, the conductive system, or the heart muscle, leading to dysfunction of the device. The blades must be positioned at least 12 cm away from the generator, preferably in the anteroposterior position. The lowest possible electrical charge must be used.

Pregnancy

Cardioversion can be used safely during pregnancy. The fetal beat should be monitored throughout the procedure.

Things To Consider

Keep your devices tested!

Working in the ED is not easy. This is the place where organization and preparation should be routine. Constant checking of materials and operation of the equipment must be the rule because the smallest detail can cause a difference in saving a life.

During adversity, it is necessary to remain calm, trying to not affect the reasoning and disposition of the team. It is an arduous job, it takes practice and a lot of effort. Errors can only be corrected after they are recognized and must have the right time to be exposed. It happens.

There is no time for despair, yelling and stress when it comes to CPR.

No conductive gel, what can we do?

The main guidelines regarding the use of the conductive gel used in the defibrillator paddles are:

Using the proper gel for this purpose is essential. The gel is an electrically conductive material that decreases the resistance to the flow of electric current between the paddle and the chest wall. The absence of conductive material can lead to the production of an arc that causes burns in the patient and the risk of explosion if there is an oxygen source very close, among others.
Avoid the use of gauze soaked in saline solution, as the excess serum can cause burns on the patient’s skin, but it is a reasonable option, in an emergency
Do not use the ultrasound gel
The preference is to use adhesive paddles that already come with their own conductive gel (but this is rare in Brazil).

Location recommended by Advanced Cardiac Life Support (ACLS)

Antero-lateral

One paddle is placed on the right side of the sternum, right below the clavicle and the other laterally where the cardiac appendix would be in the anterior or medial axillary line (V5-V6).

Adhesive paddles can also be placed in an anteroposterior position: The anterior one is placed in the cardiac appendage or precordial region, and the posterior one is placed on the back in the right or left infrascapular region.

During the shock, the provider must ensure that no one is in contact with the patient. A force of approximately 8k must be used to increase the contact of the paddles with the chest. Do not allow a continuous flow of oxygen over the patient’s chest to avoid accidents with sparks.

Complications

Electric arc (when electricity travels through the air between the electrodes and can cause explosive noises, burns and impair current delivery)
Electrical injuries in spectators
Risk of explosion if there is a continuous flow of oxygen during the shock
Burning of the skin by repeated shocks
Myocardial injury and post-defibrillation arrhythmias and myocardial stunning
Skeletal muscle injury
Fracture of thoracic vertebrae

References and Further Reading

Sunde, K., Jacobs, I., Deakin, C. D., Hazinski, M. F., Kerber, R. E., Koster, R. W., Morrison, L. J., Nolan, J. P., Sayre, M. R., & Defibrillation Chapter Collaborators (2010). Part 6: Defibrillation: 2010 international consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations. Resuscitation, 81 Suppl 1, e71–e85. https://doi.org/10.1016/j.resuscitation.2010.08.025
Panchal, A. R., Bartos, J. A., Cabañas, J. G., Donnino, M. W., Drennan, I. R., Hirsch, K. G., Kudenchuk, P. J., Kurz, M. C., Lavonas, E. J., Morley, P. T., O’Neil, B. J., Peberdy, M. A., Rittenberger, J. C., Rodriguez, A. J., Sawyer, K. N., Berg, K. M., & Adult Basic and Advanced Life Support Writing Group (2020). Part 3: Adult Basic and Advanced Life Support: 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation, 142(16_suppl_2), S366–S468. https://doi.org/10.1161/CIR.0000000000000916
Ionmhain, U. N. (2020). Defibrillation Basics. Life in The Fastlane. Retrieved April 26, 2020, from https://litfl.com/defibrillation-basics/
Paradis, N. A., Halperin, H. R., Kern, K. B., Wenzel, V., & Chamberlain, D. A. (Eds.). (2007). Cardiac arrest: the science and practice of resuscitation medicine. Cambridge University Press.
Nickson, C. (2020). Defibrillation Pads and Paddles. Life in The Fastlane. Retrieved April 26, 2020, from https://litfl.com/defibrillation-pads-and-paddles/

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Acute Management of Supraventricular Tachycardias

January 10, 2020January 10, 2020 ~ Elif Dilek Cakal, Turkey ~ Leave a comment

The term “supraventricular tachycardia (SVT)” expresses all kinds of rhythms that meet two criteria: Firstly, the atrial rate must be faster than 100 beats per minute at rest. Secondly, the mechanism must involve tissue from the His bundle or above. Mechanism-wise, atrial fibrillation resembles SVTs. However, supraventricular tachycardia traditionally represents tachycardias apart from ventricular tachycardias (VTs) and atrial fibrillation (1,2).

Supraventricular tachycardias are frequent in the ED!

The SVT prevalence is 2.25 per 1000 persons. Women and adults older than 65 years have a higher risk of developing SVT! SVT-related symptoms include palpitations, fatigue, lightheadedness, chest discomfort, dyspnea, and altered consciousness.

How to manage supraventricular tachycardia?

In clinical practice, SVTs are likely to present as narrow regular complex tachycardias. Concomitant abduction abnormalities may cause SVTs to manifest as wide complex tachycardias or irregular rhythms. However, 80% of wide complex tachycardias are VTs. Most importantly, SVT drugs may be harmful to patients with VTs. Therefore, wide complex tachycardias should be treated as VT until proven otherwise (1,2).

The chart below summarizes acute management of regular narrow complex tachycardias:

References and Further Reading

Brugada, J., Katritsis, D. G., Arbelo, E., Arribas, F., Bax, J. J., Blomström-Lundqvist, C., … & Gomez-Doblas, J. J. (2019). 2019 ESC Guidelines for the management of patients with supraventricular tachycardia: the Task Force for the management of patients with supraventricular tachycardia of the European Society of Cardiology (ESC). European Heart Journal, 00, 1-66.
Page, R. L., Joglar, J. A., Caldwell, M. A., Calkins, H., Conti, J. B., Deal, B. J., … & Indik, J. H. (2016). 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Journal of the American College of Cardiology, 67(13), e27-e115.