Delays to chest compressions and defibrillation after prehospital rearrest

Abstract

Introduction: Prehospital rearrest following return of spontaneous circulation (ROSC) is associated with low rates of survival, and delays to chest compressions and defibrillation in rearrest are poorly understood. We aimed to characterize delays in initiation of chest compressions and defibrillation delivery following rearrest.

Methods: We included out-of-hospital cardiac arrest patients with on-scene ROSC in an urban emergency medical services (EMS) network between 2021 and 2023. Cases without interpretable waveform data were excluded. We defined ROSC as 60 s without any chest compressions or non-perfusing rhythms. Delays were measured from the start of ventricular fibrillation (VF) or asystole to the time of chest compressions or defibrillation. We inferred patient movement with an exploratory method using monitor disconnection times.

Results: Of 235 patients, 114 (49 %) experienced rearrest. Of 10 with a rearrest rhythm of asystole, 6 (60 %) had a delay >10 s from rhythm onset to chest compressions with a median delay of 18 s (IQR 3, 41). Of 16 patients with a rearrest rhythm of VF, 12 (80 %) had defibrillation delayed >10 s with a median delay of 67 s (IQR 29, 245), 3 (20 %) patients were not defibrillated, and 1 had pads disconnected during the initial appearance of VF. Of 55 patients with inferred movement intervals, 30 (55 %) rearrests occurred before or during movement.

Conclusion: In this cohort, rates of rearrest and rearrest treatment delays were high. Future research should aim to determine if treatment delays are associated with worse outcomes and investigate strategies to mitigate treatment delay.

Keywords: Defibrillation; Emergency medical services; Out-of-hospital cardiac arrest; Prehospital; Rearrest.