Abstract P58: Impact of 2005 AHA Guidelines on OOHCA Survival
Objective: To describe changes in out-of-hospital sudden cardiac arrest (OOHCA) survival before and after the release of the 2005 AHA guidelines for CPR and ECC.
Methods: Analysis of survival data from a pre-established Utstein style OOHCA registry was conducted for 1923 adult cases of OOHCA treated by EMS between April 1, 2004 and December 31, 2007. These data represented all adult cases treated by one EMS system in a large metropolitan area (population 711,432). The primary endpoint was survival to hospital discharge. A convenience sample of 69 electronic ECG recordings was also analyzed using impedence waveform analysis to assess CPR quality parameters during corresponding time periods. Intervention: Implementation of the 2005 AHA Guidelines for CPR and ECC in Spring 2006.
Results: Annual OOHCA incidence rate was 72/100,000, and VF incidence rate was 15/100,000. Bystander CPR rates were 27%, and 8% of arrests occurred in a public location. PAD AED use was 2% over the entire study period and few patients received hypothermia therapy. Unadjusted OOHCA survival rates were significantly higher in the post-guidelines period 8.2% (n=1055) than in the pre-guidelines period 5.3% (n=868) despite similarities in all major predictors of outcome (OR 1.6; 95% CI 1.05–1.69). Bystander witnessed OOHCA survival for victims with VF on EMS arrival was 18 of 89 (20%) pre-guidelines vs. 31 of 110 (28%) post-guidelines (OR 1.55; 95% CI 0.8 –3.0). CPR quality measures showed significant improvement in the post-guideline period. The mean no-flow fraction (NFF) in the pre-guidelines group was 0.46 (95% CI 0.41– 0.51), while the mean NFF in the post-guidelines group was 0.34 (95% CI 0.29 – 0.40). Multivariate regression analysis controlling for significant predictors of survival showed that OOHCA in the post-guidelines time period were associated with 1.75 greater odds of survival than those in the pre-guidelines time period (95% CI 1.17–2.62).
Conclusion: Substantial improvement occurred in overall OOHCA survival rates following the implementation of the 2005 AHA Guidelines for CPR and ECC. These changes are associated with improvements in the quality of CPR.