Early administration of epinephrine (adrenaline) in patients with cardiac arrest with initial shockable rhythm in hospital: propensity score matched analysis. BMJ Feb 2016.
Adrenaline has been used for resuscitation after cardiac arrest for decades in both shockable and non-shockable rhythm. It has been previously shown that delay in the first administration of adrenaline is associated with a decreased chance of good outcomes in both adults and children in hospital who experience cardiac arrest with an initial non-shockable rhythm. There is however a lack of published studies in such patients presenting with a shockable rhythm (pulseless ventricular tachycardia or ventricular fibrillation). This is a prospective observational cohort study which attempts to address this. This study included 2978 patients who experienced cardiac arrest with an initial shockable rhythm. 51% of patients received adrenaline within 2 minutes after the first defibrillation, which is contrary to current American Heart Association (and also Australian Resuscitation Council) guidelines. Adrenaline given within the first 2 minutes after the first defibrillation was associated with decreased odds of survival (OR 0.70, 95% CI 0.59 to 0.82; P<0.001). Early adrenaline administration was also associated with decreased odds of return of spontaneous circulation (OR 0.71, 0.60 to 0.83; P<0.001) and good functional outcome (0.69, 0.58 to 0.83: P<0.001). The biggest limitation is that being an observational study, no strong causal effect of early adrenaline administration can be made. These findings may still be of relevance to future guidelines and studies.