Recent trends in survival from out-of-hospital cardiac arrest in the United States.
BACKGROUND
Despite intensive efforts over many years, the United States has made limited progress in improving rates of survival from out-of-hospital cardiac arrest. Recently, national organizations, such as the American Heart Association, have focused on promoting bystander cardiopulmonary resuscitation, use of automated external defibrillators, and other performance improvement efforts.


RESULTS
Using the Cardiac Arrest Registry to Enhance Survival (CARES), a prospective clinical registry, we identified 70 027 U.S. patients who experienced an out-of-hospital cardiac arrest between October 2005 and December 2012. Using multilevel Poisson regression, we examined temporal trends in risk-adjusted survival. After adjusting for patient and cardiac arrest characteristics, risk-adjusted rates of out-of-hospital cardiac arrest survival increased from 5.7% in the reference period of 2005 to 2006 to 7.2% in 2008 (adjusted risk ratio, 1.27; 95% confidence interval, 1.12-1.43; P<0.001). Survival improved more modestly to 8.3% in 2012 (adjusted risk ratio, 1.47; 95% confidence interval, 1.26-1.70; P<0.001). This improvement in survival occurred in both shockable and nonshockable arrest rhythms (P for interaction=0.22) and was also accompanied by better neurological outcomes among survivors (P for trend=0.01). Improved survival was attributable to both higher rates of prehospital survival, where risk-adjusted rates increased from 14.3% in 2005 to 2006 to 20.8% in 2012 (P for trend<0.001), and in-hospital survival (P for trend=0.015). Rates of bystander cardiopulmonary resuscitation and automated external defibrillator use modestly increased during the study period and partly accounted for prehospital survival trends.


CONCLUSIONS
Data drawn from a large subset of U.S communities suggest that rates of survival from out-of-hospital cardiac arrest have improved among sites participating in a performance improvement registry.
From Saint Luke's Mid America Heart Institute, Kansas City, MO (P.S.C., F.T.); the Department of Emergency Medicine, Emory University, and Rollins School of Public Health, Atlanta, GA (B.M.); and the Uniformed Services University of the Health Sciences, Bethesda, MD (A.K.). pchan@saint-lukes.org.
Paul S
PS
Chan
From Saint Luke's Mid America Heart Institute, Kansas City, MO (P.S.C., F.T.); the Department of Emergency Medicine, Emory University, and Rollins School of Public Health, Atlanta, GA (B.M.); and the Uniformed Services University of the Health Sciences, Bethesda, MD (A.K.).
Bryan
B
McNally
From Saint Luke's Mid America Heart Institute, Kansas City, MO (P.S.C., F.T.); the Department of Emergency Medicine, Emory University, and Rollins School of Public Health, Atlanta, GA (B.M.); and the Uniformed Services University of the Health Sciences, Bethesda, MD (A.K.).
Fengming
F
Tang
From Saint Luke's Mid America Heart Institute, Kansas City, MO (P.S.C., F.T.); the Department of Emergency Medicine, Emory University, and Rollins School of Public Health, Atlanta, GA (B.M.); and the Uniformed Services University of the Health Sciences, Bethesda, MD (A.K.).
Arthur
A
Kellermann
D000368:Aged; D000369:Aged, 80 and over; D016887:Cardiopulmonary Resuscitation / Q000639:trends; D047548:Defibrillators / Q000639:trends; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy*; D011446:Prospective Studies; D012042:Registries; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology
cardiac arrest; survival; trends