Long-term prognosis following resuscitation from out-of-hospital cardiac arrest: role of aetiology and presenting arrest rhythm.

OBJECTIVE Little is known about long-term prognosis following resuscitation from out-of-hospital cardiac arrest, especially as it relates to the presenting rhythm or arrest aetiology. We investigated long-term survival among those discharged alive following resuscitation according to presenting rhythm and arrest aetiology. METHODS We conducted a cohort investigation of all non-traumatic adult out-of-hospital cardiac arrest patients resuscitated and discharged alive from hospital between January 1, 2001 and December 31, 2009 in a large metropolitan emergency medical service system. Information about demographics, circumstances, presenting arrest rhythm and aetiology was collected using the dispatch, EMS, and hospital records. Long-term vital status was ascertained using state death records and the Social Security Death Index through 31st December 2010. We used Kaplan Meier to evaluate survival. RESULTS During the study period, a total of 1001/5958 (17%) persons were resuscitated and discharged alive, of whom 313/1001 (31%) presented with a non-shockable rhythm and 210/1001 (21%) had a non-cardiac aetiology. Overall median survival was 9.8 years with 64% surviving >5 years. Five-year survival was 43% for non-shockable rhythms compared to 73% for shockable rhythms, and 45% for non-cardiac aetiology compared to 69% for cardiac aetiology (p<0.001 respectively). CONCLUSION Cardiac arrest due to non-shockable rhythm or non-cardiac aetiology comprises a substantial proportion of those who survive to hospital discharge. Although long-term survival in these groups is less than their shockable or cardiac aetiology counterparts, nearly half are alive 5 years following discharge. The findings support efforts to improve resuscitation care for those with non-shockable rhythms or non-cardiac cause.