Limits of Transfusion Burden as a Predictor of Mortality in Severely Injured Trauma Patients

Severe hemorrhage remains a leading cause of early and preventable mortality in trauma patients. While massive transfusion protocols (MTPs) have improved resuscitation strategies, the prognostic value of transfusion burden alone remains unclear. This study evaluated the reliability of total blood product and blood cooler issuance as predictors of mortality in trauma MTP and assessed the added prognostic value of early laboratory parameters, neurological status on arrival and injury severity scores.

We conducted a retrospective cohort study of adult trauma patients requiring MTP activation upon arrival to a Level I trauma center between January 2023 and May 2025. Demographic, clinical, transfusion, and first laboratory data obtained within 15 to 30 minutes of presentation were analyzed. Blood cooler utilization was categorized as ≤5, 6-10, or >10 coolers. Outcomes were defined as survival or death at the conclusion of MTP.

A total of 135 patients were included; 36 (26.7%) expired during MTP activation. Non-survivors received significantly greater numbers of red blood cells, plasma, and total blood products requiring higher numbers of blood coolers. They also demonstrated more severe coagulopathy, higher lactate levels, greater metabolic derangement, lower platelet counts, hypothermia, lower Glasgow Coma Scale scores, and higher injury severity. Kaplan Meier and Cox regression analyses showed no statistically significant association between cooler category and survival. A transfusion threshold of ≥36 total blood units yielded modest predictive performance (accuracy 69.6%) using Youden's index. Integration of laboratory markers significantly improved mortality prediction models (AUC from 0.62 to 0.78).

In trauma patients requiring MTP activation, mortality was driven primarily by injury severity, neurologic status, and early physiologic derangements. Blood product utilization demonstrated limited prognostic value in isolation but contributed meaningfully when combined with laboratory and clinical parameters. Blood cooler notifications may serve as useful adjuncts to prompt timely clinical reassessment.