A new report by the Cardiac Arrest Registry to Enhance Survival (CARES) Surveillance Group, involving an evaluation of trends between 2005 and 2012, suggests that rates of survival from out-of-hospital cardiac arrest have improved in the multiple geographically diverse sites participating this performance improvement registry. The study is the largest conducted to date in the United States.
"Overall rates of survival from out-of-hospital cardiac arrest improved dramatically between 2005 and 2012," according to Paul Chan, MD, MSc and colleagues. "This finding stands in stark contrast to the lack of progress in out-of-hospital cardiac arrest survival over the preceding 30 years in the United States."
The improvements were noted in cases of both shockable and nonshockable cardiac rhythms, and were accompanied by lower rates of neurological disability among survivors. Bystander CPR and use of AEDs contributed to the improved trends. Other factors include a renewed focus on high-quality CPR and avoidance of interruptions in compressions.
"If national efforts to disseminate an easier-to-perform and retain method of CPR (hands-only CPR) lead to marked improvements in rates of bystander CPR--which parenthetically was initiated in only one-third of our study cohort--additional gains in survival may be realized," the authors said.
(Information on the use of therapeutic hypothermia was not routinely tracked before 2011, so the authors were unable to assess its impact during the study period.)
Study Highlights
Highlights include the following findings:
Demographics (2012)
- Average age of patient: 64
- Men: 61%
- Whites: 42%, Blacks: 21%
- Fewer than 50% of cases were witnessed
- 24% of patients had cardiac arrests amenable to defibrillation treatment
Location of arrest (2012)
- 85% cardiac arrests occured in private residences
- 1.7% of cardiac arrests occured in a public area with likely access to an AED
- 12.5% of cardiac arrests occured in other public places
Bystander intervention
- Rates of bystander CPR increased from 28.2% of cases in 2005-06 to 36.3% of cases in 2012
- There was a modest increase in the rate of AED use by bystanders, from 1.9% to 4.2%
- In witnessed arrests, bystander AED use increased from 6.6% to 9.4%.
Survival rates
- Overall survival rates increased from 5.7% in 2005-06 to 9.8% in 2012
- Among cases in which the patient was in a shockable rhythm, survival rates increased from 16.1% in 2005-06 to 27.9% in 2012.
Following is the abstract, published in the November 18 issue of Circulation.
Abstract
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.
Methods and Results
Using 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.
Authors: Paul Chan, MD, MSc, Bryan McNally, MD, MPH, Fengming Tang, BS, and Arthur Kellerman, MD, MPH.SOURCE: American Heart Association
-Summary prepared by Sudden Cardiac Arrest Foundation
See related report in Medical XPress.