Abstract 17394: A Single-Site Sensitivity Analysis of the Trial of Continuous or Interrupted Chest Compressions During CPR
Introduction: The “Trial of Continuous (CCC) or Interrupted Chest Compressions (ICC) during CPR” compared CPR strategies for out-of-hospital cardiac arrest (OHCA), with no evidence of outcome differences (survival at discharge: CCC 9.0%, ICC 9.7%; p=0.07). Regional variations may have played a role in protocol adherence and outcomes. We separately analyzed the cohort enrolled in British Columbia (BC) to understand whether a local change in protocol from CCC was warranted.
Methods: This was a post-hoc analysis of patients enrolled in BC. The primary comparison was favorable neurological outcome (modified Rankin scale ≤ 3) at hospital discharge using intention to treat (ITT) analysis. Secondary analyses included: per protocol, and among the top 25% percentile of compliant enrolling clusters (ITT). Protocol violations were classified prospectively using a structured algorithm by review of the defibrillator download, with ≥ two pauses per cycle ≥ 25 seconds apart classified as ICC. We performed an adjusted analysis using logistic regression and computed the difference in probabilities using the marginal standardization method with bootstrapping to calculate confidence intervals.
Results: The cohort included 3769 patients. The median age was 69 (IQR 56-80), 44% were bystander witnessed, and 25% had initial shockable rhythms. Overall survival was 12%, with 11% having favourable neurological outcomes. Of those randomized to CCC (n=1917) and ICC (n=1852) respectively, there were 61 (3.2%) and 499 (26.9%) protocol violations. In patients randomized to CCC or ICC, favorable neurological outcomes occurred in 11.2% and 10.8% (p= 0.68), respectively. Secondary comparisons can be seen in table 1. Only bystander CPR factor was significantly associated with compliance (adjusted OR 1.2 95% CI 1.0 – 1.5).
Conclusion: Although no clear difference in outcomes was seen between groups, the outcomes of our comparisons suggest that CCC may be the preferred strategy in our region.
Author Disclosures: B. Grunau: None. R. Straight: None. R. Schlamp: None. R. Wand: None. W. Dick: None. J. Singer: None. T. Lee: None. H. Connolly: None. S. Pennington: None. F. Scheuermeyer: None. J. Christenson: None.
- © 2016 by American Heart Association, Inc.