Early identification of bleeding in trauma patients: external validation of traumatic bleeding scores in the Swiss Trauma Registry

Background: Early identification of bleeding at the scene of an injury is important for triage and timely treatment of injured patients and transport to an appropriate facility. The aim of the study is to compare the performance of different bleeding scores. Methods: : We examined data from the Swiss Trauma Registry for the years 2015 to 2019. The Swiss Trauma Registry includes patients with major trauma (injury severity score (ISS) ≥ 16 and/or abbreviated injury scale (AIS) head ≥ 3) admitted to any level one trauma center in Switzerland. We evaluated ABC, TASH, and Shock index (SI), used to predict massive transfusion (MT) and the BATT score, used to predict death from bleeding. We evaluated the scores when used prehospital and in-hospital in terms of discrimination (C-Statistic) and calibration (calibration slope). The outcomes were massive transfusion and death from bleeding. Results: : We examined data from 13,222 major trauma patients. There were 1,533 (12%) deaths from any cause, 344 (3%) deaths from bleeding and 128 (1%) patients who received a MT. The BATT score had the highest discrimination for MT (C-statistic: 0.87, 95%CI 0.84-0.90) followed by SI (0.84, 95%CI 0.80-0.88) and ABC (0.82, 95%CI 0.77-0.86). At hospital admission, the BATT score had the highest discrimination for death from bleeding (0.89, 95%CI 0.87-0.90) but the TASH score had the highest discrimination for MT (C-statistic: 0.94, 95%CI 0.92-0.95). Conclusions: : The BATT score can be used to estimate the risk of death from bleeding for prehospital treatment decision-making. Others scores predicting MT are not suitable to identify life-threatening bleeding. Trial registration: Clinicaltrials.gov, NCT04561050. Registered 15 September 2020.