Out-of-hospital cardiac arrest: incidence, process of care, and outcomes in an urban city, Korea

We aimed to determine the incidence, processes of care, and outcomes in out-of-hospital cardiac arrests (OHCA) in Ansan, South Korea. From the Ansan Fire Department's (1-1-9 emergency call number) Emergency Medical Services (EMS) database, we obtained a list of adult cardiac arrest cases occurring between January 2008 and December 2011. We excluded cases with obvious non-cardiac causes, such as trauma, drowning, hanging, and asphyxia. We matched the EMS data with in-hospital care and outcome data. We analyzed basic demographic variables (age and gender), the time and place of incidence, witnesses, bystander cardiopulmonary resuscitation (CPR), major time variables, CPR instructions during transport, initial cardiac rhythm at the scene, and automated defibrillator use. The overall incidence of OHCA in Ansan was 33.1/100,000 persons per year. Out of 778 adult OHCAs in our study population, bystander CPR was provided in 103 cases (13.2%). Of the 517 OHCAs whose initial rhythms were confirmed, 85 (16.4%) showed shockable rhythms, but only 23 (27.1%) received defibrillation at the scene or during transportation. Of the 106 patients whose spontaneous circulation returned at the hospital, only 6 (5.7%) received mild therapeutic hypothermia. During the study period, 31 patients (4%) survived to discharge from hospitals, and 6 of these discharged patients (19.4%) showed favorable neurologic outcomes. While the survival rate from OHCA in Ansan is very low, this study provides basic information needed to create improvements. Our analysis suggests that multiple variables contribute to the low OHCA survival rate. Several of these variables are modifiable; addressing them is a clear first step toward strengthening the chain of survival from OCHA in Ansan.