Is One Dose of Epinephrine Enough for OHCA?

Written by Samuel Rouleau

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This secondary analysis compared out-of-hospital-cardiac-arrest (OHCA) with a single dose of epinephrine to standard ACLS and found mixed results in outcomes.

Epinephrine dosing like Goldilocks – how much is just right?
The authors initially completed a pre-post implementation study of EMS systems in North Carolina, evaluating rates of ROSC and survival to hospital discharge (SHD) in those with OHCA who received ACLS recommended multiple doses of epinephrine (MDEP, n=899) versus single-dose epinephrine (SDEP, n=791). Their first paper reported similar SHD rates in the MDEP and SDEP groups (13.6% v 15.4%). Rates of ROSC were lower in the MDEP group compared to the SDEP group (32.5% v 42.3%).

This paper reports the results of a pre-planned secondary analysis of the interaction between bystander CPR and shockable rhythm between the MDEP and SDEP groups.

• For those who received bystander CPR, SHD was 4.4% lower in the MDEP group (not statistically significant). The adjusted model found an increases odds of SHD with the SDEP group (OR 1.61, 95%CI 1.03-2.53).
• For those who did not receive bystander CPR, ROSC was lower in SDEP (32.5% SDEP vs 47.1% MDEP). The rate of SHD was similar. However, neurologic outcomes were numerically worse (not statistically significant) among survivors in the no bystander CPR cohort who received SDEP.
• The proportion of shockable rhythms was significantly different between MDEP (16%) and SDEP (22.8%). There was no statistical difference in rates of SHD between MDEP and SDEP for those who had shockable and non-shockable rhythms. However, rates of ROSC were lower in both those with shockable and non-shockable rhythms in the SDEP group compared to MDEP.
• Unadjusted neurologic outcomes among survivors were worse in those with non-shockable rhythms who were in the SDEP protocol.

How will this change my practice?
The missing piece is: How much epinephrine did patients receive in the MDEP protocol? I would love to see a secondary analysis looking at cumulative epinephrine dosing. Nevertheless, based on this study, for patients with OHCA and bystander CPR or IHCA with immediate CPR, it is reasonable to give one dose of epinephrine and focus on running a high-quality code. However, there is not enough evidence for me to withhold epinephrine at this time, with the exception of specific circumstances where epinephrine is contraindicated.

Source
Does Single Dose Epinephrine Improve Outcomes for Patients with Out-of-Hospital Cardiac Arrest and Bystander CPR or a Shockable Rhythm? Prehosp Emerg Care. 2025;29(1):37-45. doi: 10.1080/10903127.2024.2348663. Epub 2024 May 21. PMID: 38713769