Objective: The aim of this study was to determine if providing automated external defibrillators (AEDs) to urban police officers would increase the proportion of patients with out-of-hospital cardiac arrest (OOH-CA) who were discharged alive from the hospital.
Methods: This prospective, controlled study was conducted in a city with about 332,000 persons. The EMS system included paramedic ambulances and fire department based first responders equipped with defibrillators, but police officers did not respond routinely to medical emergencies. Between March 1997 and February 1999, all OOH-CAs in four police districts were identified and followed until death or hospital discharge. All 35 police cars in one police district were provided with AEDs, and all police officers in that district were trained in CPR and the use of AEDs. Police and fire first response units were dispatched simultaneously in district 3 (intervention group). Fire first response was dispatched without police in districts 2, 4, and 5 (control group).
Results: A total of 645 OOH-CAs occurred over the 2 years. Sixty-two were outside of the study area. Two did not have accurate address information to determine the police district. Of the remaining cases, 154 (27%) occurred in the intervention district and 427 (73%) were in the control area. Survival to hospital discharge was similar; it was 11/154 (7.1%) in the intervention and 16/427 (3.8%) in the control districts (odds ratio=1.98; 95% CI 0.90--4.36). Survival to hospital discharge for witnessed OOH-CA events occurring prior to EMS arrival and found to be in ventricular fibrillation or ventricular tachycardia was 4/27 (15%) in the intervention area and 9/73 (12%) in the control area (odds ratio=1.2; 95% CI 0.4-4.4).
Conclusion: Equipping police cars with AEDs in an urban area where the fire department-based first response system also carries defibrillators did not improve the hospital discharge survival rate for victims of OOH-CA.