Abstract 97: Analysis of Emergency Medical Service-initiated CPR Effectiveness in Out-of Hospital Cardiac Arrest (OHCA) Cases Without Bystander-CPR: From all-Japan OHCA Utstein Registry

Abstract

Backgrounds: Bystander cardiopulmonary resuscitation (CPR) is essential for good neurological survival (GNS) in out-of-hospital cardiac arrest (OHCA). However previous reports from the All-Japan prospective, population-based OHCA Utstein registry of the Fire and Disaster Management Agency(J-OHCAUR) revealed that around 50% of OHCA did not receive bystander-initiated CPR and treated by the emergency medical service (EMS). The present study examined relationship among the time interval from the witnessed cardiac arrest to EMS-initiated CPR and shock, and GNS one month after the event. Methods and Results: From January 2005 through December 2011, we identified 140,363 witnessed OHCA cases from the J-OHCAUR. Among them, 74,541 cases (53.1%) did not receive bystander-CPR, and 14,911 cases had the initial rhythm of VF or VT. These EMS-initiated CPR cases were classified according to the time-interval from cardiac arrest to CPR and shock; 1,106 in the time-interval of 0 minute (shock first approach), 2.707 in 1 minute, 4.131 in 2 minutes, 2,304 in 3 minutes, 985 in 4 minutes, and 1,047 in 5 to 10 minutes. Rate of GNR (cerebral performance category scale 1 or 2) in each time-intervals were shown in the figure. Effectiveness of CPR was clearly time-dependent, and the earlier shock brought about the better GNS in any time-intervals. Conclusion: Even in OHCA cases without bystander-CPR, time-dependent effectiveness of EMS-initiated CPR and importance of the earlier shock were documented.