Nationwide dissemination of public-access AEDs in Japan resulted in earlier administration of shocks by laypersons and in an increase in the 1-month rate of survival with minimal neurologic impairment after an out-of-hospital cardiac arrest.

Fire and Disaster Management Agency and the Ministry of Education, Culture, Sports, Science and Technology (Japan).

Background-The impact of ongoing efforts to improve the "chain of survival" for out-of-hospital cardiac arrest (OHCA) is unclear. The objective of this study was to evaluate the incremental effect of changes in prehospital emergency care on survival after OHCA. Methods and Results-This prospective, population-based observational study involved consecutive patients with OHCA from May 1998 through December 2006. The primary outcome measure was 1-month survival with favorable neurological outcome. Multiple logistic regression analysis was used to assess factors that were potentially associated with better neurological outcome. Among 42 873 resuscitation-attempted adult OHCAs, 8782 bystander-witnessed arrests of presumed cardiac origin were analyzed. The median time interval from collapse to call for medical help, first cardiopulmonary resuscitation, and first shock shortened from 4 (interquartile range [IQR] 2 to 11) to 2 (IQR 1 to 5) minutes, from 9 (IQR 5 to 13) to 7 (IQR 3 to 11) minutes, and from 19 (IQR 13 to 22) to 9 (IQR 7 to 12) minutes, respectively. Neurologically intact 1-month survival after witnessed ventricular fibrillation increased from 6% (6/96) to 16% (

Background-Previous animal and clinical studies suggest that bystander-initiated cardiac-only resuscitation may be superior to conventional cardiopulmonary resuscitation (CPR) for out-of-hospital cardiac arrests. Our hypothesis was that both cardiac-only bystander resuscitation and conventional bystander CPR would improve outcomes from out-of-hospital cardiac arrests of Յ15 minutes' duration, whereas the addition of rescue breathing would improve outcomes for cardiac arrests lasting Ͼ15 minutes. Methods and Results-We carried out a prospective, population-based, observational study involving consecutive patients with emergency responder resuscitation attempts from May 1, 1998, through

Among adult patients with OHCA, any type of advanced airway management was independently associated with decreased odds of neurologically favorable survival compared with conventional bag-valve-mask ventilation.