Abstract 58: Out-of-Hospital Cardiac Arrest Outcomes Stratified by Rhythm Analysis
Background: Survival data for OHCA victims initially in PEA or asystole who convert to a shockable rhythm during attempted resuscitation, relative to an initial shockable rhythm, have never been previously reported. This study was done to assess OHCA outcomes among a large cohort of adults in the Cardiac Arrest Registry to Enhance Survival dataset stratified by three rhythm categories: converted shockable (CS), initial shockable (IS) and never shockable (NS).
Methods: The study was IRB approved. All adult index events at participating sites (2004–2009) were study eligible. All patient data elements were provided. Odds ratios of CS and NS status for survival to hospital discharge were calculated via multivariate logistic regression that adjusted for demographics, site, CPR initiators, AED use and other covariates.
Results: Of the 20,018 available files, 854 were ineligible and excluded. This left 19,164 records for analysis (1,939 CS [10.1%], 4,559 IS [23.8%], 12,672 NS [66.1%]). Raw survival rates of CS and NS patients were similar (4.0% vs. 3.8% respectively; p=0.65) but significantly lower than IS patients (25.5% p<0.001). The adjusted OR of survival to hospital discharge for CS was 0.15 (95% CI 0.12, 0.20) and for NS it was 0.17 (95% CI 0.15, 0.19) with IS as the referent. When stratified by PEA and asystole, CS PEA had a lower OR than NS PEA (0.10 [95% CI 0.06, 0.16] vs. 0.24 [95% CI 0.19, 0.30], p<0.001) but CS asystole had a higher OR than NS asystole (0.15 [95% CI 0.10, 0.21] vs. 0.10 [95% CI 0.09, 0.12], p=0.053). Good cerebral performance category classification in survivors was as follows: 33.8% for CS, 28.2% for NS and 61.5% for IS.
Conclusion: After OHCA, the survival rate for CS victims is significantly lower than for IS patients. These findings suggest that CS and IS are different entities and that alternatives to the existing VF resuscitation algorithm tailored to patients with CS should be investigated.
- © 2010 by American Heart Association, Inc.