Epinephrine in Cardiac Arrest: Identifying a Potential Limit for Resuscitation

Area of Science:

• Emergency Medicine
• Cardiology
• Clinical Research

Background:

• Epinephrine is a cornerstone of Advanced Cardiac Life Support (ACLS) despite limited evidence of improved neurologically intact survival.
• Real-world epinephrine administration patterns and their impact on patient outcomes require further investigation.

Purpose of the Study:

• To determine an upper limit for effective epinephrine use during resuscitation.
• To analyze real-world epinephrine administration in various patient subgroups.

Main Methods:

• A retrospective cohort study of 1,330 patients with medical cardiac arrest receiving a known number of epinephrine doses.
• Primary outcome: neurologically intact discharge (modified Rankin scale ≤3).
• Secondary outcomes: epinephrine dose comparison by age, rhythm, and administration setting (EMS vs. ED).

Main Results:

• Neurologically intact discharge rates decreased significantly with increasing epinephrine doses (0 doses: 65.4%; 1-3 doses: 20.0%; 4-6 doses: 4.3%; ≥7 doses: 0.002%).
• Patients with shockable rhythms received more epinephrine than those with non-shockable rhythms.
• Epinephrine administration was similar across age groups.

Conclusions:

• Higher epinephrine doses are associated with significantly lower rates of neurologically intact survival.
• Seven or more epinephrine doses may indicate futility in resuscitation efforts.
• Clinicians should consider the number of epinephrine doses when evaluating the benefit versus futility of continued resuscitation.