Hypothermia on trauma center arrival has a much greater impact on outcomes at the extremes of age.

Abstract

Hypothermia is a potentially modifiable risk factor for poor outcomes in trauma; differences in impact of hypothermia on different age groups are not well-defined. This study characterized the effects of varying levels of hypothermia on injured patients by age. We hypothesized that pediatric and geriatric trauma patients would be disproportionately impacted by hypothermia. This retrospective cohort study included all patients with a valid arrival temperature from the 2020 to 2023 Trauma Quality Improvement Program database. Patients were categorized by arrival temperature: normothermia (36 to 38°C), mild hypothermia (35 to 35.9°C), severe hypothermia (<35°C), or hyperthermia (>38°C), and by age group (≤5, 6 to 11, 12 to 15, 16 to 17, 18 to 39, 40 to 64, 65 to 79, or >80 y). Outcomes were in-hospital mortality and early (<4 h) blood transfusion. Multivariable logistic regression evaluated the combined effects of arrival temperature and age group on outcomes, adjusting for confounding variables. Of 4,135,371 patients, 244,203 (5.9%) had mild and 37,839 (0.9%) severe hypothermia. Mortality was 28.1% in severe hypothermia versus 8.8% mild hypothermia versus 1.9% normothermia (P<0.0001); early transfusion occurred for 30.0% in severe hypothermia versus 13.5% mild hypothermia versus 3.2% normothermia (P<0.0001). Multivariable logistic regression demonstrated that hypothermia had different effects on different age groups. Odds of mortality showed a U-shaped distribution across the age spectrum, with children and elderly patients experiencing the highest impact of hypothermia (odds ratios 17.3 for age <5, 12.1 for 6 to 11, 9.7 for 12 to 15, 6.1 for 16 to 17, 4.8 for 18 to 39, 4.6 for 40 to 64, 5.4 for 65 to 79, and 7.1 for >80 years with severe hypothermia). Early blood transfusion showed similar patterns. Hypothermia disproportionately affects pediatric and elderly patients, exacerbating their risk of mortality and early blood transfusion. The findings highlight the importance of recognizing and responding to hypothermia at the extremes of age. Strategies to mitigate traumatic hypothermia should be further investigated and optimized based on age group. (J Trauma Acute Care Surg. 2026;00: 00-00. Copyright © 2026 Wolters Kluwer Health, Inc. All rights reserved.). Prognostic/Epidemiologic; Level III.