Epinephrine for cardiac arrest: knowns, unknowns and controversies

The aim of this study was to describe our knowledge about the use of epinephrine in cardiac arrest and discuss the unknowns and current controversies.

A recent large, well conducted, double-blind, randomized placebo-controlled trial of over 8000 patients with out-of-hospital cardiac arrest (PARAMEDIC-2) showed that epinephrine increased return of spontaneous circulation and survival to hospital discharge. The trial's secondary outcomes have raised concerns that epinephrine increases the number of brain damaged survivors. Systematic review and meta-analysis suggest that epinephrine has more pronounced effects for nonshockable rhythms, when given early, and probably increases the number of both good and poor survivors. There remains uncertainty about the optimal use of epinephrine in terms of patient groups, rhythms, dose and timing.

Epinephrine still has a role in the treatment of cardiac arrest; the best way to use epinephrine remains uncertain.