Therapeutic hypothermia for out-of-hospital cardiac arrest: An analysis comparing cooled and not cooled groups at a Canadian center

Abstract

Background: Out of hospital cardiac arrest is a devastating event and is associated with poor outcomes; however, therapeutic hypothermia (TH) is a novel treatment which may improve neurological outcome and decrease mortality. Despite this, TH is not uniformly implemented across Coronary Care and Intensive Care Units in Canada. Objective: The purpose of this study was to compare cerebral recovery and mortality rates between patients in our Coronary Care Unit who received TH with a historical control group. Materials and Methods: A retrospective chart review was performed of patients admitted to a tertiary care center with out-of-hospital cardiac arrest. Twenty patients who were admitted and cooled after December 2006 were compared with 29 noncooled patients admitted in the 5 years prior as a historical control group. The primary outcomes of interest were in-hospital mortality and neurological outcome. Results: Eleven of 20 (11/20, 55%) patients who were cooled as per protocol survived to hospital discharge, all having a good neurological outcome. Eleven of 29 (11/29, 38%) noncooled patients survived to hospital discharge (Odds Ratio: 0.50, 95% CI: 0.16- 1.60, P=0.26). Eleven of 20 patients who were cooled had a good neurological outcome (CPS I-II, 11/20, 55%), versus 7 of 29 (7/29, 24%) of noncooled patients (Odds ratio: 3.84, 95% CI: 1.13- 13.1, P=0.03). One hundred percent (11/11) of survivors in the cooled group had a good neurological outcome. Conclusion: In our center, the use of TH in out-of-hospital cardiac arrest survivors was associated with improved neurological outcome.

Keywords

• Cardiac arrest
• neurological outcomes
• therapeutic hypothermia