The association between initial defibrillation dose and outcomes following adult out-of-hospital cardiac arrest resuscitation: a retrospective, multi-agency study.

Abstract

Introduction: Effective defibrillation is essential to out-of-hospital cardiac arrest (OHCA) survival. International guidelines recommend initial defibrillation energies between 120 and 360 Joules, which has led to widespread practice variation. Leveraging this natural experiment, we aimed to explore the association between initial defibrillation dose and outcome following OHCA.

Methods: The ESO Data Collaborative (2018-2022) was used for this nationwide, retrospective study of adult (18-80 years of age) non-traumatic OHCA patients who presented with an initially shockable ECG rhythm. We excluded patients if they had ROSC prior to initial defibrillation, a resuscitation-limiting advanced directive, or were residents in a healthcare institution. The primary exposure was initial defibrillation dose, defined as Joules per kilogram of body weight, and the primary outcome was return of spontaneous circulation (ROSC). We included survival to discharge as a secondary outcome. We used multivariable logistic regression modeling to assess the relationship between defibrillation dose and outcome.

Results: We analyzed data from 21,121 patients. Of the 12,160 patients linked to a defibrillator manufacturer, 7,240 (59.5%) were treated using a biphasic truncated exponential (BTE) waveform and 4,920 (40.5%) were treated using a rectilinear biphasic (RLB) waveform. Defibrillation dose (per 1 J/kg increase) was not associated with ROSC (BTE aOR: 0.97 [0.92, 1.01], n=7,240; RLB aOR: 1.00 [0.92, 1.09], n=4,920; all aOR: 1.01 [0.98, 1.04], 21,121) or survival (BTE aOR: 0.98 [0.87, 1.10], n=1,245; RLB aOR: 0.89 [0.70, 1.12], n=775; all aOR: 1.00 [0.92, 1.08], n=2,981).

Conclusions: Initial defibrillation dose was not associated with outcome in this nationwide cohort.