Impact of a resuscitation protocol prioritizing airway clearance in the COVID-19 pandemic for patients with ventricular fibrillation: a retrospective observational study in Nagoya, Japan

Objective: During the coronavirus disease 2019 (COVID-19) pandemic, the prehospital resuscitation protocol in Nagoya was altered to prioritize airway clearance before adrenaline administration to reduce the risk of coronavirus infection.This study evaluated how this protocol change influenced outcomes for patients experiencing out-of-hospital cardiac arrest (OHCA) with an initial waveform of ventricular fibrillation (VF)/pulseless ventricular tachycardia (VT) in Nagoya, Japan.Methods: We utilized emergency transport data collected by the Nagoya City Fire Bureau.Data from witnessed OHCA cases with an initial waveform of VF/VT were categorized into pre-pandemic (April 1, 2018, to March 31, 2020) and pandemic periods (April 1, 2020, to March 31, 2023).The implementation of the resuscitation protocol and patient outcomes were analyzed.Results: A total of 371 patients were eligible, with 138 in the pre-pandemic period and 233 during the pandemic.During the pandemic, the interval between the emergency call and hospital arrival increased significantly (23 minutes vs. 25 minutes, P=0.026), as did the interval to adrenaline administration (13 minutes vs. 16 minutes, P<0.001).After propensity score matching for bystander interventions, patient characteristics, and emergency medical services (EMS) contact time, the odds ratio (OR) for prehospital return of spontaneous circulation (ROSC) during the pandemic was significantly lower (OR, 0.57; 95% confidence interval [CI], 0.35-0.94).One-month survival was also significantly lower (OR, 0.58; 95% CI, 0.35-0.94).Conclusion: Delayed adrenaline administration and EMS contact following protocol changes during the COVID-19 pandemic likely contributed to reduced prehospital ROSC and 1-month survival rates.