Abstract
Background In 2002, the out-of-hospital cardiac arrest ( OHCA ) survival rate in Detroit was the lowest in the nation. Concerted efforts sought to improve the city's chain of survival with a focus on emergency medical services ( EMS ). This study assesses the impact on OHCA survival rates and describe factors associated with survival. Methods and Results Data for non-traumatic OHCA cases in Detroit from 2014 to 2016 were extracted from CARES (Cardiac Arrest Registry to Enhance Survival). Chi-squared tests, non-parametric tests, and a multivariable logistic regression analysis were employed to examine the associations between overall survival and its covariates. A total of 2359 non-traumatic OHCA cases were examined. The overall survival rate increased from 3.7% in 2014 to 5.4% in 2015, and 6.4% in 2016 ( P<0.01), reflecting a 73% improvement in survival over the 3-year period. EMS median on-scene time decreased over the study period, while the rate at which EMS initiated cardiopulmonary resuscitation and applied an automated external defibrillator (AED) greatly increased ( P<0.001). The factors significantly associated with survival were female sex (odds ratio=1.70, P<0.05), a public setting (odds ratio=2.31, P<0.01), an EMS witness (odds ratio=6.18, P<0.01), and the presence of an initial shockable rhythm (odds ratio=1.88, P<0.05). Conclusions From 2014 to 2016, the overall survival rate for OHCA patients in Detroit, MI significantly improved. Our results suggest that an improved chain of survival may explain this progress. This study is an example of how OHCA data analysis and EMS improvement can improve end OHCA outcomes in a resource-limited urban setting.