Outcomes of Out-of-Hospital Cardiac Arrest with Initial Shockable Rhythm: The Role of Bystander and Dispatch-Guided CPR in Sarajevo's Physician-Led Emergency Medical Teams

Background: The Out-of-hospital cardiac arrest (OHCA) remains a major public health challenge worldwide, with survival outcomes heavily influenced by early intervention. The presence of an initial shockable rhythm significantly increases the likelihood of survival when combined with timely cardiopulmonary resuscitation (CPR) and defibrillation. Objective: To analyze patient outcomes and the incidence of bystander and dispatch-guided CPR in cases of OHCA with an initial shockable rhythm treated by physician-led emergency medical teams in Bosnia and Herzegovina. Methods: Data for this study were collected over a 5-year period, from January 2019 to September 2023, using the Utstein protocol. Hospital records were analyzed to determine patient outcomes, with a focus on the 30-day survival rate and favorable neurological outcomes. Instances of dispatch-guided and bystander CPR were recorded for each case based on available patient records. Results: In this study, 1,020 patients were included, with 151 cases (14.8%) having an initial shockable rhythm, of which 14.3% of males and 4.4% of females achieved return of spontaneous circulation (ROSC). ROSC rates varied by year, with the highest in 2019 (20.4%) and 2022 (17.9%). Thirty-day survival with a good neurological outcome was observed in a small percentage of cases. The initial shockable rhythm was found to be statistically significant (p<0.001) for achieving a good neurological outcome after 30 days. Dispatch-guided CPR was attempted in 12.9% of cases, with success in 1.9%. Bystander CPR was performed in 1.4% of cases, and only one case involved the use of an automated external defibrillator (AED). The median response time for successful resuscitations was 2 minutes, while for unsuccessful resuscitations, it was 6 minutes. The findings emphasize the role of age, initial rhythm, and response time in determining outcomes for OHCA patients. Conclusion: The promising survival rate of OHCA patients, despite limited bystander CPR, highlights the impact of short response times and skilled physician-led teams, underscoring the need for public education and a unified registry to address gaps and better understand OHCA epidemiology in Bosnia and Herzegovina.