What do prehospital trauma scores predict besides mortality?

Background: Little information is available concerning the ability of pre-hospital triage scores to predict endpoints other than mortality. Methods: We evaluated two cohorts (a national cohort of 1,360 patients during 2002 and a single center cohort of 1,003 patients in 2003-2005) of trauma patients receiving care from a prehospital mobile intensive care unit (ICU). We tested the ability of prehospital triage scores (MGAP, Revised Trauma Score [RTS], and triage RTS [T-RTS]) to predict a severe injury, the need for a prolonged ICU period, the occurrence of massive hemorrhage, and the need for emergency procedures, and compared them with a reference score (Trauma-Related Injury Severity Score [TRISS]). The areas under the receiver operating characteristic (AUC(ROC)) curves were measured. Results: The MGAP, RTS, and T-RTS scores were able to predict an Injury Severity Score > 15 (AUC(ROC) : 0.75, 0.75, and 0.74, respectively), the need for a stay in ICU > 2 days or death (AUC(ROC) of 0.85, 0.83, and 0.83, respectively), and the massive hemorrhage (AUC(ROC) : 0.70, 0.72, and 0.73, respectively). In contrast, MGAP, RTS, T-RTS, and TRISS scores were not predictors of the need of an emergency procedure (AUC(ROC) : 0.53, 0.51, and 0.52, respectively). Four independent predictors of emergency procedure were noted: penetrating trauma, intravenous colloid administration > 750 mL, systolic arterial blood pressure < 100 mm Hg, and heart rate > 100 bpm. Conclusion: Prehospital triage scores were predictors of Injury Severity Score > 15, prolonged ICU stay, and massive hemorrhage but not of emergency procedure requirement.