Association between transfusion volume and survival outcome following trauma: Insight into the limit of transfusion from an analysis of nationwide trauma registry in Japan

Abstract Background Whether and how the transfusion volume should be limited in resuscitation after trauma remains unclear. We investigated the association between transfusion volume and survival outcome following trauma. Methods Using the Japan Trauma Data Bank (2019–2021), we identified patients aged ≥18 years who received balanced blood transfusion within the first 24 h of injury. We evaluated the association between the total number of red blood cell (RBC) units transfused and survival at discharge using logistic regression analysis and generalized additive model. Subgroup analyses based on patient characteristics were performed. Results Overall, 5123 patients from 165 hospitals were eligible for analysis. The transfusion volume was significantly associated with survival rate. Compared to that of patients receiving 4–9 RBC units, the within-hospital odds ratios (95% confidence interval) for survival at discharge were 0.62 (0.55–0.75), 0.32 (0.25–0.40), and 0.15 (0.12–0.20) for those receiving 10–19, 20–29, and ≥ 30 units, respectively. The probability of survival decreased consistently without any discernible threshold; however, the survival rates remained >40% and > 20% even in patients receiving 50 and 80 RBC units, respectively. Significant interactions were observed between the number of RBC units transfused and each subgroup for survival at discharge. Conclusions The probability of survival consistently diminished as the transfusion volume increased. The absence of a threshold and lack of exceedingly low probability of survival support massive transfusion when clinicians perceive ongoing transfusion as beneficial. The unique context of each clinical situation must be considered in decision-making. Level of evidence III, therapeutic/care management.