Evaluating The Effectiveness Of Community Cardiopulmonary Resuscitation (CPR) In Improving Out-Of-Hospital Cardiac Arrest Survival: Is There A Need For A Complementary Community-Based Intervention?

Abstract

Out of Hospital Cardiac Arrest is a major public health problem that claims about 1000 lives everyday. Despite major advances in healthcare and prehospital medicine, the national survival rate ranges from 7% to 9%, and varies greatly between communities. Layperson Cardiopulmonary Resuscitation (CPR) has been associated with increases in survival to hospital discharge with varying degrees of effectiveness. Although the role of community CPR was expanded and emphasized, some communities have reported no success of a bystander CPR intervention, which raises questions about its limitations and factors that may indirectly influence its effectiveness. Using a sample of 45,394 OHCA cases (from 2010 through 2014) that was obtained from the Cardiac Arrest Registry to Enhance Survival, this study aims to evaluate the effectiveness of bystander CPR, examine the indirect effects of a community baseline survival rate and response time of prehospital providers on the association between bystander CPR and survival. This study utilized a retrospective parallel comparative design where patients receiving bystander CPR were compared to those without it. The effect modifications of the baseline rate and response time were assessed using a multilevel logistic regression and an ordinary least squares regression designs. The overall survival rate was 10.3%. Survival in the intervention group was 15% compared to 8% for the control (OR=2.35, p<0.001). The effect modifications were only supported for the baseline rate and not the response time. The association between the intervention and survival was strong at low baseline rates but was nullified at higher rates. Additionally a survival plateau of over 10% was evident at communities with a bystander CPR rate of 30% or more. Bystander CPR is indeed effective in improving survival in communities with a baseline rate less than 10%, beyond which its effectiveness is limited and in some cases nullified. The baseline and bystander CPR rates at a community should be considered when incorporating a CPR program to ensure its efficacy and address its limitation. Communities with high baseline and bystander CPR rates may benefit from complementary interventions more than from expanding bystander CPR. Research is warranted to explore and confirm such indirect associations.