Cardiac Arrest
Olivia C. Welter, PharmD
In January 2024, the American Heart Association (AHA) released a guideline update for CPR and emergency cardiovascular care.
Based on input from various AHA committees, the guideline document includes recommendations for clinical trial diversification, routine medication administration for cardiac arrest, temperature control, organ donation, and anti-seizure medication considerations.
Pharmacotherapy during cardiac arrest
Within the guideline update, the authors provide insights into both vasopressor medications and nonvasopressor medications used when patients are in active cardiac arrest requiring CPR.
For vasopressors, the guideline authors recommend epinephrine administration during cardiac arrest due to the increased potential risk for coronary and cerebral perfusion during CPR. According to the guidelines, health care personnel should administer 1 mg of epinephrine every 3 to 5 minutes during cardiac arrest and, for patients with nonshockable rhythm, administering epinephrine as soon as feasible is also reasonable. For shockable rhythm, clinicians may consider initiating epinephrine after initial defibrillation attempts fail. Finally, the guidelines do not recommend high-dose epinephrine for routine use in cardiac arrest.
The authors note that no definitive evidence exists showing nonvasopressors, such as antiarrhythmic medications, magnesium, or calcium, having any positive effect on overall survival following cardiac arrest. However, administering amiodarone or lidocaine to patients with out-of-hospital cardiac arrest may improve survival during the time it takes to admit such patients to the hospital. The supporting evidence, which was reviewed by the guideline-writing group, suggested that the benefit of amiodarone or lidocaine may be time dependent as it has been most effective in cases when bystanders witnessed the cardiac arrest, allowing for emergency medical services to quickly respond.
Due to lack of demonstrated benefit, the guidelines do not recommend routine administration or use of calcium, sodium bicarbonate, or magnesium products. Steroid use during CPR for out-of-hospital cardiac arrest patients is of uncertain benefit.
Temperature control
For cardiac arrest patients, the guidelines emphasize the importance of temperature control of the person’s body, especially for those patients who are unresponsive to commands following reestablishment of their cardiac rhythm.
Historically, health care providers have used cooling devices or I.V. liquids to lower a patient’s body temperature once their heart begins beating again.
In this update, the upper limit for temperature control was raised to 37.5° C with the recommendation that clinicians select a temperature between 32° C and 37.5° C at which the patient will be constantly maintained. Additionally, authors suggest that maintaining the patient at the chosen temperature for at least 24 hours after achieving the target temperature is reasonable. While a target body temperature range is provided in the guidelines, the writing group also recommends that individual hospitals develop their own protocols to follow when approaching post-arrest temperature control.
Seizure considerations
Unfortunately, seizures are common in cardiac arrest patients who are unresponsive to commands following their cardiac rhythm being re-established. For such patients, health care providers should promptly perform an EEG and monitor continuously for the presence of seizure activity, according to the update.
Additionally, any adult cardiac arrest survivor should receive treatment for clinically apparent seizures. However, the guideline writing group emphasizes that seizure prophylaxis is not necessary and should not be routinely deployed for cardiac arrest patients.
Other recommendations
The guidelines emphasize the importance for cardiac arrest survivors to consider becoming organ donors in the event of their death. The writing group also calls for researchers studying cardiac arrest to put in place strategies to recruit participants from diverse backgrounds for future research and to report participant demographics in published research to better quantify cardiac arrest disparities. ■