Shorter defibrillation interval promotes successful defibrillation and resuscitation outcomes

Abstract Aim Current cardiopulmonary resuscitation guidelines recommend performing defibrillation every 2 minutes during resuscitation. This study aimed to compare the rate of successful defibrillation using 1- and 2-minute defibrillation intervals. Methods Twenty-six pigs were randomly assigned to 1- or 2-minute interval groups. After inducing ventricular fibrillation (VF), we observed pigs for 2 minutes. Thereafter, basic life support was initiated with a 30:2 compression-to-ventilation ratio for 8 minutes. Defibrillation was performed with an energy of 2 J/kg at 10 minutes after VF and was repeated every 1 or 2 minutes according to randomization. Advanced cardiac life support, including continuous chest compression with ventilation every 6 seconds and intravenous injection of 1 mg epinephrine every 3 minutes, was performed until the return of spontaneous circulation (ROSC) or until 20 minutes after VF induction. Haemodynamic parameters and baseline arterial blood gas profiles were compared between groups. ROSC, 24 -h survival, and the neurologic deficit score (NDS) were evaluated at 24 hours. Results Haemodynamic parameters during resuscitation and baseline arterial blood gas profiles did not differ between groups. ROSC was more frequently observed in the 1-minute interval group (p = 0.047). Time to ROSC was not different between groups (p = 0.054). The 24 -h survival was higher (p = 0.047) and NDS at 24 hours was lower (92 ± 175) in the 1-minute interval group than in the 2-minute interval group (272 ± 190) (p = 0.028). Conclusions Defibrillation success and resuscitation outcomes were superior when using a 1-minute defibrillation interval in animal models of cardiac arrest.