Abstract 26: Long-Term Prognosis Following Out-of-Hospital Cardiac Arrest: Role of Etiology and Initial Rhythm

Abstract

Background: The proportion of out-of-hospital cardiac arrest due to non-shockable rhythms or non-cardiac etiology is increasing. Little is known about long-term prognosis following resuscitation, especially as it relates to the presenting rhythm or arrest etiology. We investigated long-term survival among those discharged alive following resuscitation overall and according to presenting rhythm and etiology. Methods: We conducted a cohort investigation of all adults suffering out-of-hospital cardiac arrest in a large metropolitan EMS system between Jan 1,2001 and Dec 31,2009 who were resuscitated and discharged from hospital. We prospectively collected pre-hospital data including initial rhythm and arrest etiology. Long-term vital status was ascertained using death certificate records through Dec 31,2010. We used Kaplan Meier and Cox regression to evaluate survival. Results: During the study period, 6149 adults received EMS resuscitation,of whom 4165 (69%) presented a non-shockable rhythm and 2198 (36%) had a non-cardiac etiology. A total of 1001 were discharged alive, of whom 316/1001 (32%) presented a non-shockable rhythm and 213/1001 (21%) had a non-cardiac etiology. Overall median survival was 9.8 yrs with 62% surviving >5-yrs after hospital discharge. Five-year survival was 42% for non-shockable rhythms compared to 71% for shockable rhythms,and 45% for non-cardiac etiology compared to 66% for cardiac etiology (p<0.01 respectively) (Fig1). Conclusion: Cardiac arrest due to non-shockable rhythm or non-cardiac etiology comprises a substantial proportion of those who survive and are discharged from the hospital. Although long-term survival in these groups is less than their shockable or cardiac etiology counterparts, over half are alive 4 years following hospital discharge, a finding that suggests meaningful survival and supports continued efforts to improve resuscitation care for those with non-shockable rhythms or non-cardiac cause.