PREHOSPITAL SHOCK INDEX MULTIPLIED BY AVPU SCALE AS A PREDICTOR OF CLINICAL OUTCOMES IN TRAUMATIC INJURY

Objectives: Many prehospital trauma triage scores have been proposed, but none has emerged as a criterion standard. Therefore, a rapid and accurate tool is necessary for field triage. The shock index (SI) multiplied by the AVPU (Alert, responds to Voice, responds to Pain, Unresponsive) score (SIAVPU) reflected the hemodynamic and neurological conditions through a combination of the SI and AVPU. This study aimed to investigate the prediction performance of SI multiplied by the AVPU and to compare the prediction performance of other prehospital trauma triage scores in a population with traumatic injury. Patients and Methods: This study included 6,156 patients with trauma injury from the Taipei Tzu Chi trauma database. We investigated the accuracy of four scoring systems in predicting mortality, intensive care unit (ICU) admission, and prolonged hospital stay (defined as a duration of hospitalization >14 days). In the subgroup analysis, we also analyzed the effects of age, injury mechanism and severity, underlying diseases, and traumatic brain injury. Results: The predictive accuracy of SIAVPU for mortality, ICU admission, and prolonged hospital stay was significantly higher than that of SI, modified SI, and SI multiplied by age in the traumatic injury population, with an area under the receiver operating characteristic curve of 0.738 for mortality, 0.641 for ICU admission, and 0.606 for prolonged hospital stay. In the subgroup analysis, the prediction accuracy of mortality, ICU admission, and prolonged hospital stay of SIAVPU was also better in patients with younger age, older age, major trauma (Injury Severity Score >= 16), motor vehicle collisions, fall injury, healthy, cardiovascular disease, mixed traumatic brain injury, and isolated traumatic brain injury. The best cutoff levels of SIAVPU score to predict mortality, ICU admission, and total length of stay >= 14 days in trauma injury patients were 0.90, 0.82, and 0.80, with accuracies of 88.56%, 79.84%, and 78.62%, respectively. Conclusions: In conclusion, SIAVPU is a rapid and accurate field triage score with better prediction accuracy for mortality, ICU admission, and prolonged hospital stay than SI, modified SI, and SI multiplied by age in patients with trauma. Patients with SIAVPU >= 0.9 should be considered for the highest-level trauma center available within the geographic constraints of regional trauma systems.