Perioperative red blood cell infusion and deep vein thrombosis in patients with femoral and pelvic fractures: a propensity score matching

Background The relationship between perioperative red blood cell (RBC) infusion and deep vein thrombosis (DVT) has not been determined. Objectives To analyze the time-event relationship between perioperative RBC infusion and DVT in patients with femoral and pelvic fractures after adjusting for confounding factors and to provide reference for optimizing DVT risk factors. Methods The clinical data of 569 patients with femoral and pelvic fractures who received surgical treatment from May 2018 to December 2019 were retrospectively analyzed. Propensity score matching (PSM) was performed on 20 covariates of DVT. With the formation or progression of DVT after RBC infusion as the end point, the time-event relationship between perioperative RBC infusion and DVT in patients was analyzed by binary logistic regression. Results After 1:1 PSM of 569 patients included in this study, 126 patients were in the transfusion group and the non-transfusion group, respectively. Before PSM (P = 0.023, OR = 1.496 [95% CI, 1.058-2.115]), perioperative RBC infusion was associated with DVT formation for femoral and pelvic fractures. This conclusion was still obtained after PSM (P = 0.038, OR = 1.728, 95% CI = (1.031, 2.896)). The risk of DVT in patients with RBC infusion of 2-4U and > 4U is 1.833 and 2.667 times that of [less than or equai to] 2U, respectively. After excluding patients who received preoperative RBC infusion and had DVT formation or progression prior to RBC infusion, perioperative RBC infusion was still associated with the formation of DVT in femoral and pelvic fractures (P = 0.037, OR = 2.231 [95% CI, 1.049-4.745]). Conclusion Perioperative RBC infusion is one of the causes of DVT in patients with femoral and pelvic fractures, and the risk of DVT is positively correlated with the amount of RBC infusion. Keywords: Red blood cell infusion, Femoral fracture, Pelvic fracture, Deep vein thrombosis, Propensity score matching