High Undertriage in Geriatric Trauma in a Developing Trauma System: Implications for Trauma Team Activation Criteria

INTRODUCTION: Older adults are at increased risk of adverse outcomes after trauma but are frequently undertriaged because age-related physiological changes may mask injury severity. We evaluated the performance of our institutional trauma team activation (TTA) criteria in patients aged ≥ 65 years within a developing trauma system. METHODS: We conducted a retrospective observational study using a trauma registry at a tertiary referral hospital in Malaysia between July 2024 and December 2025. Consecutive trauma patients aged ≥ 65 years admitted to the trauma surgery unit were included. Patients were stratified according to TTA status. Severe injury was defined as an Injury Severity Score (ISS) > 15. The primary outcomes were TTA sensitivity, specificity, and undertriage. Secondary outcomes included mortality, intensive care unit (ICU) admission, and operative intervention. RESULTS: A total of 114 geriatric trauma patients were included, of whom 59 (51.8%) sustained severe injury (ISS > 15). TTA was activated in 17 patients (14.9%). The institutional TTA criteria demonstrated a sensitivity of 28.8% and specificity of 100%, with an undertriage rate of 43.3% and no overtriage. Overall in-hospital mortality was 14.0% (16/114) and was higher among patients undergoing TTA (64.7% vs. 5.2%, p < 0.001), reflecting greater injury severity. Severe traumatic brain injury accounted for 68.8% of deaths, and five of the sixteen deaths (31.3%) occurred in patients who did not meet TTA criteria. CONCLUSION: Current TTA criteria demonstrated low sensitivity for identifying severely injured geriatric trauma patients, resulting in substantial undertriage despite excellent specificity. Missed patients frequently sustained severe traumatic brain injury without meeting existing activation criteria. These findings support prospective evaluation of geriatric-specific modifications to trauma triage, including age-adjusted physiological thresholds and lower thresholds for trauma team activation in older adults.