An Analysis of the Association of Arrival Hemoglobin With Overtransfusion at 24 Hours in a Trauma Population.

Background: Hemorrhage control and resuscitative concepts have evolved in recent years, leading to aggressive use of blood products in trauma patients. There is subsequently a potential risk for overtransfusion, adverse effects, and waste associated with unnecessary transfusion. Methods for conserving blood products are of particular importance in future large-scale combat operations where supply chains are likely to be strained. This study examined the association of emergency department (ED) arrival hemoglobin (HGB) with overtransfusion among survivors at 24 hours after major trauma at a military trauma center.

Materials and methods: We performed a retrospective cohort study of patients who had a "major trauma" activation and received any red blood cells. Overtransfusion was defined as a HGB level ≥11.0 g/dL at 24 hours (outcome variable). Multivariable logistic regression statistics were used to compare groups and adjust for confounders (injury severity score, arrival modified shock index, injury type, age, and gender). A receiver operating characteristic was constructed with overtransfusion at 24 hours as the outcome (binary) and arrival HGB (continuous) as the independent variable.

Results: A total of 382 patients met inclusion criteria. Overtransfusion occurred in 30.4% (n = 116) of patients, with mean ED HGB levels of 13.2 g/dL (12.9 to 13.6) versus 11.6 g/dL (11.3 to 11.8, P < .001). Receiver operating characteristic analysis showed that ED HGB was highly sensitive (0.931) for predicting 24-hour overtransfusion. In our multivariable logistic regression analysis, when adjusting for injury severity score, arrival modified shock index, injury type, age, and gender, we found that the ED HGB value had a per-unit odds ratio of 1.60 (95% CI, 1.38 to 1.86) for 24-hour overtransfusion. Hospital and intensive care unit length of stay, mechanical ventilator days, and mortality did not increase.

Conclusion: We found that the arrival HGB value was associated with overtransfusion among 24-hour survivors in a civilian trauma setting. Our findings will inform future prospective studies that investigate blood sparing clinical practice guidelines.