Venous Thromboembolic Events in Adult Trauma Patients Receiving Balanced Hemostatic Resuscitation (BHR): An Analysis of Their Incidence, Predictors, and Associated Mortality Rates at a Level 1 Trauma Center

Abstract

Background and objective Studies assessing the incidence of venous thromboembolic (VTE) events in the setting of massive balanced transfusions and/or tranexamic acid (TXA) infusion have yielded varied outcomes. In light of this, we conducted this study to examine the incidence of VTEs in trauma patients requiring blood products, and to identify the risk factors for VTE and mortality in this population. Methods We performed a retrospective analysis of trauma patients admitted to our level 1 trauma center from January 2013 to September 2023. Clinical characteristics were compared between patients who developed VTE and those who did not. A regression analysis of potential variables associated with the development of VTEs and mortality was performed. Results Among 1305 patients (mean age: 42.4 ± 18.8 years) receiving blood products within the initial 24 hours, 4.3% (56 patients) developed a VTE. Patients with VTE experienced prolonged ICU and hospital stays and ventilation duration (p<0.001). They were also noted to have delayed initiation of VTE prophylaxis (104.2 vs. 50.3 hours, p<.001). Prolonged ventilation >7 days was the sole significant factor associated with VTE in multivariate regression analysis [odds ratio (OR): 6.2, p=0.004]. Early TXA administration (within four hours) showed a higher association with VTE than TXA within 24 hours (OR: 2.1, p=0.07 vs. OR 1.6, p=0.22). Massive transfusion was found to increase VTE risk (OR: 2.65, p<0.001). Severe head and neck (OR: 6.0, p=0.002) and chest (OR: 3.8, p=0.01) injuries were key predictors of mortality, while TXA was not significantly associated with mortality in the multivariate model. Conclusions Our study revealed an elevated risk of VTE in patients requiring massive transfusion protocol (MTP, ≥6 units). Early TXA administration was neither associated with increased VTE risk in MTP patients nor increased mortality risk. Strategies directed at reducing the risk of VTE in massively transfused patients while maintaining the survival benefits of balanced resuscitation and TXA need to be devised.

Keywords: balanced resuscitation; massive transfusion; mortality; predictors; tranexamic acid; trauma; venous thromboembolism.

Figure 1. Flowchart depicting the selection process and categorization for subgroup analyses

DVT: deep vein thrombosis; MTP: massive transfusion protocol; PE: pulmonary embolism; TXA: tranexamic acid; VTE: venous thromboembolism

Figure 2. Incidence of VTE with the increasing number of units of the three main blood products (pRBC, FFP, and PLT)

Grey line: incidence of VTE (n%). Orange line: incidence of VTE in patients who received TXA. Blue line: incidence of VTE in patients without TXA FFP: fresh frozen plasma; PLT: platelets; pRBC: packed red blood cells; VTE: venous thromboembolism

Figure 3. Receiver operating characteristic curve (ROC) showing the predictive power of the multivariate logistic regression model

Area under the curve (AUC): 0.84. Accuracy: 0.91