Does Mechanism of Injury Predict Trauma Center Need?

Abstract

Objective. To determine the predictive value of the mechanism-of-injury step of the American College of Surgeons Field Triage Decision Scheme for determining trauma center need. Methods. Emergency medical services (EMS) providers caring for injured adult patients transported to the regional trauma center in three midsized communities over two years were interviewed upon emergency department (ED) arrival. Included was any injured patient, regardless of injury severity. The interview collected patient physiologic condition, apparent anatomic injury, and mechanism of injury. Using the 1999 Scheme, patients who met the physiologic or anatomic steps were excluded. Patients were considered to need a trauma center if they had nonorthopedic surgery within 24 hours, had intensive care unit admission, or died prior to hospital discharge. Data were analyzed by calculating positive likelihood ratios (+LRs) and 95% confidence intervals (CIs) for each mechanism-of-injury criterion. Results. A total of 11,892 provider interviews were conducted. Of those, one was excluded because outcome data were not available, and 2,408 were excluded because they met the other steps of the Field Triage Decision Scheme. Of the remaining 9,483 cases, 2,363 met one of the mechanism-of-injury criteria, 204 (9%) of whom needed the resources of a trauma center. Criteria with a +LR ≥5 were death of another occupant in the same vehicle (6.8; CI: 2.7–16.7), fall >20 feet (5.3; CI: 2.4–11.4), and motor vehicle crash (MVC) extrication time >20 minutes (5.1; CI: 3.2–8.1). Criteria with a +LR between >2 and <5 were intrusion >12 inches (4.2; CI: 2.9–5.9), ejection (3.2; CI: 1.3–8.2), and deformity >20 inches (2.5; CI: 1.9–3.2). The criteria with a +LR ≤2 were MVC speed >40 mph (2.0; CI: 1.7–2.4), pedestrian/bicyclist struck at a speed >5 mph (1.2; CI:1.1–1.4), bicyclist/pedestrian thrown or run over (1.2; CI: 0.9–1.6), motorcycle crash at a speed >20 mph (1.2; CI: 1.1–1.4), rider separated from motorcycle (1.0; CI: 0.9–1.2), and MVC rollover (1.0; CI: 0.7–1.5). Conclusion. Death of another occupant, fall distance, and extrication time were good predictors of trauma center need when a patient did not meet the anatomic or physiologic conditions. Intrusion, ejection, and vehicle deformity were moderate predictors.

Key words: wounds and injury; triage; emergency medical services; emergency medical technicians; predictors; mechanism of injury; trauma center