Abstract 18070: Therapies Optimizing Organ Perfusion and Protection After Out-of-hospital Cardiac Arrest Improves Survival With Favorable Neurologic Outcome

Abstract

Introduction: Survival rates with favorable neurologic function after out-of-hospital cardiac arrest (OHCA) have remained low for decades. Hypothesis: Use of therapies focused on better perfusion during CPR using mechanical adjuncts and protective post-resuscitation care would improve survival and neurologic outcomes after OHCA compared to conventional CPR and care. Methods: OHCA outcomes in Alameda County, CA, USA, population 1.5 million, from December 2009-2011 when there was incomplete availability and use of impedance threshold device [ITD], mechanical CPR [MCPR], and hospital therapeutic hypothermia [HTH], were compared to 2012 when all were available and more widely used. Return of Spontaneous Circulation (ROSC), survival and Cerebral Performance Category (CPC) scores were compared using univariate and multivariable analyses. Results: Of the 3008 non-traumatic OHCAs who received CPR during the study period, >95% of survival outcome data were available. From 2009-11 to 2012, there was an increase in ROSC from 28.6% to 34.1% (p=0.002; OR=1.28; CI=1.09, 1.51) and a non-significant increase in hospital discharge from 10.5% to 12.3% (p=0.14; OR=1.17; CI=0.92, 1.49). There was, however, an 80% increase in survival with favorable neurological function between the two periods, as determined by CPC≤2, from 4.4% to 7.9% (p<0.001; unadjusted OR=1.85; CI=1.35, 2.54). After adjusting for witnessed arrest, bystander CPR, initial rhythm (VT/VF vs. others), placement of an advanced airway, EMS response time, and age, the adjusted OR was 1.60 (1.11, 2.31; p=0.012). Using a stepwise regression model, the most important independent positive predictors of CPC≤2 were 2012 (p=0.019), witnessed (p<0.001), initial rhythm VT/VF (p<0.001), and advanced airway (inverse association p<0.001). Additional analyses of the three therapies, separately and in combination, demonstrated that for all patients admitted to the hospital, ITD use with HTH had the most impact on survival to discharge with CPC≤2 of 24%. Conclusions: Therapies (ITD, MCPR, HTH) developed to enhance circulation during CPR and cerebral recovery after ROSC, significantly improved survival with favorable neurological function by 80% following OHCA.