The impact of ventricular fibrillation amplitude on successful cardioversion, resuscitation duration, and survival after out-of-hospital cardiac arrest

Objective: We sought to examine the incidence of low amplitude ventricular fibrillation and its impact on successful cardioversion, duration of resuscitation, and survival to hospital discharge in patients with out-of-hospital cardiac arrest (OHCA). Design: Retrospective analysis from a statewide registry. Setting: Victoria, Australia. Participants: Consecutive initial ventricular fibrillation arrests with an emergency medical service (EMS)- attempted resuscitation between 1 February 2019 and 30 January 2020. Main outcome measures: Survival to hospital discharge, successful cardioversion, and duration of resuscitation. Results: Of the 471 initial ventricular fibrillation arrests, 429 (91.1%) had sufficient electrocardiogram data for review. The median initial and final ventricular fibrillation amplitude did not differ (0.3 mV; interquartile range [IQR], 0.2 - 0.5 mV). The final pre-shock amplitude was