New approaches to out-of-hospital cardiac arrest

Out-of-hospital cardiac arrest (OOH-CA) is a leading cause of mortality and the focus of significant research. Recent studies provide new evidence that may change our management of OOH-CA and improve outcomes. The findings of two recently published studies of OOH-CA are reviewed in this article. The first, the Public Access Defibrillation Trial, was a randomized, controlled trial of public access defibrillation in 993 community facilities in the U.S. and Canada. It demonstrated that a community strategy to train laypersons to respond to cardiac arrests significantly increased survival to hospital discharge following OOH-CA in nonresidential community units with community members trained and equipped to provide public access defibrillation, compared to community units with community members trained to provide cardiopulmonary resuscitation (CPR) without any capacity for defibrillation. The second, the European Resuscitation Council Vasopressor during Cardiopulmonary Resuscitation Study, was a randomized, controlled, double-blinded trial that compared vasopressin to epinephrine as the initial pharmacological therapy for 1,219 patients who sustained OOH-CA. The study demonstrated that vasopressin is similar to epinephrine for OOH-CA due to ventricular fibrillation or pulseless electrical activity, and superior to epinephrine for the initial treatment of asystolic arrest; it also demonstrated that the combination of vasopressin and epinephrine is superior to epinephrine alone in the treatment of refractory, out-of-hospital cardiac arrest. Studies on alternative CPR techniques and adjunctive devices for CPR were also reviewed. We conclude that pre-hospital access to defibrillators and the use of vasopressin in the management of asystole hold promise for improving survival for patients with out-of-hospital cardiac arrest.