Abstract 63: Time to Target Temperature and Neurological Outcome in Survivors of Cardiac Arrest
Introduction: Substantial variability exists in time to target temperature for patients who undergo therapeutic hypothermia (TH) after cardiac arrest. How this variability may affect or predict neurologic outcomes is unknown.
Hypothesis: Prolonged pre-induction time, or shorter times to target temperature will be associated with poor neurologic outcomes compared to shorter pre-induction times and a more gradual decline to target temperature.
Methods: We conducted a retrospective chart review of TH patients from three institutions with identical TH protocols (PATH Database). Demographic variables were collected and analyzed using chi square and Student’s t-tests. We examined the association between time from arrest to return of spontaneous circulation (ROSC) (downtime), time from ROSC to initiation of TH (pre-induction) and time from initiation of TH to arrival at target temperature (induction) and Cerebral Performance Category (CPC) using logistic regression.
Results: We enrolled 180 patients with mean age 59.1 ± 15.5 yrs, 56% male, and 26.1% with VF/VT as an initial rhythm. At discharge, 26% (47/180) of the cohort had CPC category 1 or 2 (good neurologic outcome). Mean downtime for survivors with a good outcome was 21.5 ± 13.7 mins vs. 32.6 ± 21.7 mins (p=0.004) for those with poor outcome. Mean pre-induction time for good outcome (CPC 1 or 2) was 144.5 ± 205.4 mins compared to 145.5 ± 171.1 mins for bad outcome (p=ns). Mean induction time for good outcome (CPC 1 or 2) was 270.8 ± 160.8 mins compared to 252.3 ± 151.3 mins for bad outcome (p=ns). In analyses adjusting for gender, initial rhythm, and downtime, there was no association between pre-induction time (OR 1.00, 95% CI 0.99-1.0, p=ns) or induction time (OR 0.99, 95% CI 0.99-1.0, p=ns), and neurologic outcome.
Conclusion: In this cohort of post-arrest TH patients, pre-induction time and induction time do not appear to be associated with poor neurologic outcome. Further analysis is necessary to examine this phenomenon.
- © 2012 by American Heart Association, Inc.