Abstract
Background Little is known about whether cardiopulmonary resuscitation ( CPR ) training can increase bystander CPR in the community or the appropriate target number of CPR trainings. Herein, we aimed to demonstrate community-wide aggressive dissemination of CPR training and evaluate temporal trends in bystander CPR . Methods and Results We provided CPR training (45-minute chest compression-only CPR plus automated external defibrillator use training or the conventional CPR training), targeting 16% of residents. All emergency medical service-treated out-of-hospital cardiac arrests of medical origin were included. Data on patients experiencing out-of-hospital cardiac arrest and bystander CPR quality were prospectively collected from September 2010 to December 2015. The primary outcome was the proportion of high-quality bystander CPR . During the study period, 57 173 residents (14.7%) completed the chest compression-only CPR training and 32 423 (8.3%) completed conventional CPR training. The proportion of bystander CPR performed did not change (from 43.3% in 2010 to 42.0% in 2015; P for trend=0.915), but the proportion of high-quality bystander CPR delivery increased from 11.7% in 2010 to 20.7% in 2015 ( P for trend=0.015). The 1-year increment was associated with high-quality bystander CPR (adjusted odds ratio, 1.461; 95% CI, 1.055-2.024). Bystanders who previously experienced CPR training were 3.432 times (95% CI, 1.170-10.071) more likely to perform high-quality CPR than those who did not. Conclusions We trained 23.0% of the residents in the medium-sized city of Osaka, Japan, and demonstrated that the proportion of high-quality CPR performed on the scene increased gradually, whereas that of bystander CPR delivered overall remained stable.