Abstract 2839: Differences in Incidence and Outcome of Out-of-Hospital Cardiac Arrest Among Communities in Osaka: The Utstein Osaka Project
Introduction Awareness that survival of out-of-hospital cardiac arrest (OHCA) differs substantially among regions is growing. Differences in OHCA incidence and outcome across communities in Osaka remain to be clarified. We assessed whether OHCA incidence and outcome differ across medical districts in Osaka.
Methods This population-based prospective observational study included all adult OHCA patients resuscitated by emergency medical services (EMS) personnel in Osaka from January 1, 2005 to December 31, 2007. Osaka (8.8 million residents/1,898 square kilometers) has eight medical districts (470,000 –2,630,000 residents, median 950,000), each with a local medical control (MC) advisory board. Each board develops its own cardiopulmonary resuscitation (CPR) protocols, provides on-line medical directions to ambulance personnel, and evaluates the provision of prehospital emergency care to improve the quality of care in its medical district. All the data were prospectively collected according to the Utstein criteria in cooperation with the EMS personnel and physicians in receiving hospitals.
Results During the three years, a total of 15,942 EMS-resuscitated OHCA were reported in Osaka. Average annual incidence was 74.7 per 100,000 population for adults older than 20 years, ranging from 57.4 to 84.8 per 100,000 across the eight medical districts (P<0.001). A total of 923 (6%) were bystander-witnessed OHCA with initial rhythm of ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT); the average annual incidence was 4.3 per 100,000 adults older than 20 years, ranging from 2.8 to 5.6 per 100,000 across the medical districts (P<0.001). Survival was 289/923 (31%), ranging from 13% to 47% (P<0.001). Patients with a favorable neurological outcome accounted for 185/923 (20%), ranging from 5% to 27% (P=0.01).
Conclusions Significant differences in OHCA incidence and outcome were observed among medical districts in Osaka. MC advisory boards should make efforts to identify modifiable factors (e.g. time factors related to “the chain of survival”, CPR protocols, and postresuscitation care provided by receiving hospitals) that would contribute to improving outcomes in their community.