What Else Is Needed to Improve Survival from Out-of-Hospital Cardiac Arrest to Hospital Admission? Data from a Prospective Registry for the Years 2020-2023 in the Italian Province of Varese

Around the world, data on out-of-hospital cardiac arrest (OHCA) are heterogeneous in terms of outcomes and reporting, and not all registries follow the Utstein recommendations for uniform OHCA data collection. This study reports data on OHCA occurring in recent years in a limited territory to analyze, in a homogenous setting, the circumstances and interventions affecting survival to hospital admission. OHCA data from the province of Varese for the years 2020-2022 were extracted from a prospective registry. For survival to hospital admission, the impact of pandemic waves and variables known to affect survival was evaluated both in the overall population and in the subgroup of patients in whom cardiopulmonary resuscitation (CPR) was initiated or continued by the emergency medical service (EMS). Overall, 3263 OHCAs occurred mainly at home (88%), with a time to intervention of 13.7 min, which was significantly longer during lockdown (15.7 min). Bystanders performed CPR in 22% of the cases and used automatic external defibrillator (AED) in 2.2% of the cases. Overall survival to hospital admission was 7.7%. In the multivariate analysis, in the general population, occurrence near a public building (OR 1.92), the presence of witnesses (OR 2.65), and a shockable rhythm (OR 7.04) were independent predictors of survival to hospital admission, whereas age (OR 0.97) and occurrence during a pandemic wave (OR 0.62) were associated with significantly worse survival to hospital admission. In the group of patients who received CPR, AED shock by bystanders was the only independent predictor of survival (OR 3.14) to hospital admission. Among other factors, early defibrillation was of crucial importance to improve survival to hospital admission in possibly rescuable patients. The occurrence of OHCA during pandemic waves was associated with longer intervention time and worse survival to hospital admission.