Potential use of double sequential external defibrillation (DSED) in out-of-hospital cardiac arrest as initial strategy – a nationwide assessment

Abstract Background Defibrillation is important for survival in patients with cardiac arrest and shockable arrhythmia, such as ventricular fibrillation and pulseless ventricular tachycardia. Multiple defibrillation attempts may be necessary to achieve return of spontaneous circulation (ROSC), and each failed attempt prolongs time without ROSC. Methods to decrease the time to ROSC should be explored. Ongoing studies investigate early implementation of double sequential external defibrillation (DSED), but the potential effect of such strategies in the Norwegian cardiac arrest population remains unknown. This article investigates the number of patients that meet predefined criteria and represent a potential candidate population for future investigation of initial DSED in Norway. Methods This is a retrospective observational cohort study that includes adult patients (aged 18 and older) who experienced out-of-hospital cardiac arrest (OHCA) in Norway over an eight-year period, from 2016 to 2023. The potential candidate population for treatment with initial DSED was identified as patients who received two or more defibrillations during cardiopulmonary resuscitation (CPR). Results Over the eight-year period, 7,280 patients were shocked during CPR. Of these, 4,591 (63%) patients, or 574 patients per year, received two or more defibrillation attempts. Within this group, 1,935 (42%) patients survived the event, and 1,282 (28%) patients survived to 30 days. Conclusion Each year, approximately 574 patients required two or more defibrillation attempts and may represent a potential candidate population for future investigation of treatment with initial DSED. These findings indicate a small patient population in investigation of DSED as an initial intervention in OHCA treatment in Norway alone.