Abstract 294: The Effect of 1-Shock Protocol using Biphasic Defibrillators for Treatment of Out-of-Hospital Shockable Cardiac Arrest
BACKGROUND In recent guidelines for electrical therapy of cardiopulmonary resuscitation (CPR), there was insufficient evidence to recommend any specific biphasic waveform. When defibrillation is required, a single shock should be provided with immediate resumption of chest compressions after the shock (1-shock protocol). We investigated the effect of 1-shock protocol using biphasic defibrillators.
METHODS From the data of the All-Japan Utstein Registry, a prospective, nationwide, population-based registry of out-of-hospital cardiac arrest, we extracted the patients who were persons 18 years of age or older with bystander-witnessed shockable cardiac arrest due to cardiac etiology in the years 2005 (the 3-shock protocol era), and 2008, 2009 and 2010 (the 1-shock protocol era). The study patients were divided into 4 groups according to the two shock protocols and the two AED waveforms. The primary endpoint was 30-day favorable neurological outcome after shockable arrest.
RESULTS Of the 17,297 patients who met the inclusion criteria, 1,626 received 3-shock protocol using biphasic AEDs, 1,960 3-shock protocol using monophasic AEDs, 12,133 1-shock protocol using biphasic AEDs, and 1,578 1-shock protocol using monophasic AEDs. Figure showed comparisons of favorable neurological outcome between the 1-shock protocol and the 3-shock protocol groups, and between the biphasic AEDs and the monophasic AEDs groups. In the subgroups of patients who did not receive bystander CPR, the frequencies were similar to the results of all patients. Adjusted odds ratios for favorable neurological outcome were 2.5 (95% CI, 2.2 to 2.8) after 1-shock protocol and 1.3 (95% CI, 1.2 to 1.4) after biphasic AEDs in the whole cohort.
CONCLUSION Single-shock protocol using biphasic AEDs was superior to the others, including 1-shock protocol using monophasic AEDs, 3-shock protocol using biphasic AEDs and 3-shock protocol using monophasic AEDs, in terms of neurological benefits.
- © 2012 by American Heart Association, Inc.