Initial inferior vena cava diameter predicts massive transfusion requirements in blunt trauma patients: A retrospective cohort study.

Objectives: The inferior vena cava (IVC) diameter is associated with shock and increased mortality in trauma patients. However, there are no reports examining the association between the IVC diameter and massive transfusion (MT) requirements in trauma patients. The aim of this study was to evaluate the association between IVC diameter and MT requirements in patients with blunt trauma.

Methods: We retrospectively reviewed all patients who were consecutively hospitalized with blunt trauma (Injury Severity Score [ISS] ≥16) between from November 1, 2011 to March 30, 2016. Univariate and multivariate analyzes were performed to identify the independent predictors of MT (defined as >10units of red cell concentrate transfusions within 24h of admission). Receiver operating characteristic curve and the area under the curve (AUC) were estimated.

Results: Of the 222 patients included in this study, MT occurred in 22.5% patients. On multiple regression analysis, IVC diameter [Odds ratio (OR), 0.88; 95% confidence interval (CI), 0.80-0.96; p<0.01], fibrin degradation product (FDP; OR, 1.01; 95% CI, 1.00-1.01; p<0.01), and fibrinogen level (OR, 0.99; 95% CI, 0.98-1.00; p<0.01) were strong predictors of MT. IVC diameter demonstrated moderate accuracy (AUC, 0.74; cutoff level, 13.0mm; sensitivity, 67%; specificity, 73%). Combined cutoff levels of FDP <80.5μg/ml, fibrinogen ≥165mg/dl, and IVC diameter ≥13mm could also determine how unnecessary a MT was with 100% accuracy.

Conclusions: Initial IVC diameter is a predictor of MT in blunt trauma patients.