186 Correlates of Outcomes for 131 Consecutive Cardiac Arrest Patients Having Undergone Therapeutic Hypothermia at a Single Canadian Tertiary Referral Medical Center

Abstract

BACKGROUND: Resuscitation guidelines recommend that patients with resuscitated out-of-hospital cardiac arrest (ROOHCA) undergo treatment with therapeutic hypothermia (TH) for improved survival and neurological outcomes. It is also recommended that regional systems of care be developed to optimize the management of the post-cardiac arrest syndrome and that these programs systematically monitor the care provided and its outcomes. The Coronary Intensive Care Unit of the Foothills Medical Centre (FMC-CICU) has a standardized TH protocol for all patients with ROOHCA . This quality assurance analysis was conducted in order to document the characteristics of our current standard of care and identify possible correlates of survival and favorable neurological outcomes amongst ROOHCA patients treated with TH. METHODS: We have performed a retrospective chart review of all patients treated with a standardized TH protocol who were admitted to the CICU-FMC between January 1st 2009 and December 31st 2011. Pre-determined parameters reviewed for potential correlation with survival and favorable outcomes include age, sex, circumstances of arrest, rural vs. urban location of arrest, initial rhythm, characteristics of the resuscitation, method of cooling, and chronology of therapeutic and clinical events. RESULTS: For the 3 year period reviewed, 131 patients underwent TH. Of these, 38% were deceased during the index admission. Deceased patients were on average older (64.0 / 11.4 vs. 58.2 / 13.8 years old, p 0.01). Of those under 50 years of age, only 3 of 20 patients died during the index admission, for an 85% survival rate to discharge. Survival rate to discharge was 62.5%, 55.6%, 57.1% and 37.5%, respectively for individuals in their fifth, sixth, seventh and eighth decades of life. Other parameters and their association with mortality and neurological recovery are analysed. CONCLUSION: This quality assurance audit suggests that the comprehensive system of care for ROOHCA patients treated with TH in the FMC-CICU results in outcomes comparable to those of published clinical trials. For patients with ROOHCA of probable primary cardiac cause and committed to TH, age is inversely correlated to survival: being less than 50 years of age at the time of arrest is associated with an increased chance of survival to discharge for the index admission.