Abstract 373: Traumatic Bleeding Severity Score: An External Validation Study for the Predictive Accuracy of the Need for Massive Transfusion

Abstract

Background: The Traumatic Bleeding Severity Score (TBSS) was developed to predict the need for massive transfusion (MT). The aim of this study was to conduct the first external validation study about the TBSS in Japan, and to compare its prediction value to other pre-existing MT prediction scores. Methods: A multicenter retrospective observational study was conducted in Japan (Japanese observational study for coagulation and Thrombolysis in Early Trauma 2 : J-OCTET 2). Twenty-five tertiary critical care centers in Japan participated in this study, and severe trauma patients (Injury Severity Score : ISS ≥ 16) admitted from 2018 to 2019 were enrolled. At the analysis of the TBSS external validation, patients with isolated head injuries were excluded from the analysis. In this study, MT was defined as 10 units or more of red blood cells transfusion within 24 hours from injuries. The TBSS on admission was retrospectively calculated and its accuracy in predicting MT was analyzed by the area under the receiver operating characteristic curve (AUROC). To compare the predictive value between the TBSS and the pre-existing scores, the Trauma Associated Severe Hemorrhage score (TASH score) and the Assessment of Blood Consumption score (ABC score) on admission was similarly calculated, and the ROC comparison analysis was performed. Results: Totally, 1202 severely injured trauma patients were enrolled in the J-OCTET 2 study, and 889 patients were analyzed after the matching of the exclusion criteria. The median age was 66 years (IQR: 47-77), 71.4 % was male, 97.9% was blunt trauma, median ISS was 22 (IQR:16-29), and 13.8% received MT. The AUROC of the TBSS for was 0.848 (95% CI:0.81-0.88). According to the ROC comparison, the AUROC of the TASH score was 0.848 (95% CI: 0.81-0.88) and there was no significant difference between both prediction scores. (Bonferroni adjusted p=1.00). The AUROC of the ABC score was 0.751(95% CI: 0.70-0.80), which was significantly lower to TBSS’s (Bonferroni adjusted p<0.01). Conclusion: This TBSS external validation study showed that the accuracy of TBSS in the MT prediction was moderate accuracy. The predictive value of the TBSS was comparable to that of the TASH score and superior to the ABC score.