Early adrenaline for cardiac arrest

Adrenaline (epinephrine) has been used as a treatment for cardiac arrest since the inception of modern day resuscitation. Despite its widespread use, meta-analysis of existing randomised controlled trials has failed to show any effect or benefit on survival to discharge or neurological outcomes.1 Some observational studies have even suggested associated harm.2

In a linked paper, Donnino and colleagues (doi:10.1136/bmj.g3028) explored the effect of timing of delivery of adrenaline during in-hospital cardiac arrest.3 Using data from the American Heart Association Get With The Guidelines registry of in-hospital cardiac arrest, they constructed multivariate logistic regression models to dissect out the effect of early adrenaline on long term outcomes. The analysis focused on a specific cohort of patients—those sustaining a cardiac arrest in hospital with an initial non-shockable rhythm (asystole or pulseless electrical activity (PEA)) on a general hospital ward. It excluded most patients who sustained a cardiac arrest in a specialist clinical area (such as the emergency department or intensive care unit).

Their main finding was a stepwise decrease in hospital survival for every minute that adrenaline delivery was delayed (survival rate of 12% …