Impact of differential temperature trajectories following targeted temperature management on outcomes in out-of-hospital cardiac arrest patients receiving ECPR: a multicenter, retrospective study with prospective validation.

Abstract

The physiological patterns and clinical implications of body temperature variability following targeted temperature management (TTM) in patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) remain poorly understood. This study aimed to evaluate the association between post-rewarming temperature trajectories and survival outcomes, as well as neurological prognosis, in ECPR-treated out-of-hospital cardiac arrest (OHCA) patients. We conducted a multicenter retrospective cohort study across 6 intensive care units (ICUs) in Zhejiang Province. Adult patients with witnessed in OHCA who underwent ECPR and standardized TTM between January 2017 and December 2023 were included. Core body temperatures recorded between 48 and 72 h were analyzed by K-means-Dynamic Time Warping (DTW). The optimal number of clusters was determined by evaluating the average silhouette coefficient across a range of 2-10 clusters and selecting the value that yielded the maximum score. The primary outcome was 90-day mortality; secondary outcomes included neurological status assessed by the modified Rankin Scale (mRS) and adverse events. Moreover, the main findings were further validated in a prospective, multicenter cohort. Cluster analysis identified two groups based on temperature variability: a high-temperature variability group (HTVG, n = 107) and low-temperature variability group (LTVG, n = 170). HTVG exhibited significantly lower 90-day mortality (34.6 % vs. 53.5 %, p < 0.001), which was confirmed by Kaplan-Meier analysis (HR 2.63; 95 % CI 1.81-3.81; log-rank p < 0.001). Additionally, HTVG showed a trend toward better neurological outcomes (mRS 4-6: 43.9 % vs. 69.4 %, p < 0.001) and a lower incidence of moderate or severe bleeding (29.0 % vs. 45.9 %; p = 0.005). Besides, this finding was validated in a prospective cohort. Among OHCA patients treated with ECPR and TTM, a high temperature variability pattern temperatures recorded between 48 and 72 h is associated with lower 90-day mortality and improved neurological outcomes. These findings suggest that post-rewarming temperature trajectories may be an important prognostic indicator in this population.