Therapeutic Hypothermia Duration Explored in Comatose OHCA Survivors

THURSDAY, Aug. 13, 2026 (HealthDay News) — For comatose survivors of out-of-hospital cardiac arrest treated with therapeutic hypothermia, neurological outcomes are not improved with increasing cooling duration, according to a study published online Aug. 5 in the Journal of the American Medical Association.

William J. Meurer, M.D., from the University of Michigan in Ann Arbor, and colleagues examined the duration of therapeutic hypothermia that maximizes neurological recovery in comatose survivors of out-of-hospital cardiac arrest in a multicenter, randomized clinical trial conducted at 71 U.S. hospitals. The first 200 adults were randomly assigned to durations of 12, 24, and 48 hours of therapeutic hypothermia at 33 degrees Celsius, followed by a response-adaptive randomization algorithm allocated preferentially to the groups most likely to be optimal and to best inform the duration-response curve. The primary outcome was neurological function at 90 days, measured using a weighted modified Rankin Scale score.

Overall, 1,158 patients were randomly assigned: 883 and 275 with nonshockable and shockable rhythms, respectively. At the interim analysis, the trial met a prespecified stopping rule. The researchers found that the posterior probability that six hours was the shortest duration achieving the maximal mean weighted modified Rankin Scale score was 0.51 for the nonshockable rhythm cohort. Similar results were seen in the shockable cohort. Across cooling durations, there were no differences observed in secondary outcomes or mortality.

“Duration of therapeutic hypothermia should not be routinely extended in comatose survivors of cardiac arrest,” the authors write.

Several authors disclosed ties to industry; one has a patent for electrocardiography-guided defibrillation.

Abstract/Full Text