Venous Thromboembolism After Blood Transfusions in Women Undergoing Hysterectomy for Non-Malignant Indications: A Retrospective Cohort Study.

OBJECTIVE: To quantify the effect of blood transfusion on the risk of venous thromboembolism (VTE) among women undergoing hysterectomy for non-malignant indications.

METHODS: A retrospective cohort study using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) was conducted. Women who underwent hysterectomy for non-malignant indications between 2011 and 2016 were identified using the Current Procedural Terminology and Internationally Classification of Diseases codes. The primary outcome was development of VTE. Data on patient demographics and perioperative variables were obtained. Pair-wise comparison using χ2 tests were performed to compare women with and without VTE. Multivariable logistic regression was performed to adjust for potential confounders and identify independent predictors of VTE.

RESULTS: Between 2011 and 2016, 169 593 women underwent hysterectomy for non-malignant indications. The overall incidence of VTE was 0.32%. Patient characteristics associated with VTE included obesity and higher American Society of Anesthesiologists (ASA) status. Associated operative factors included abdominal surgery, blood transfusion, and prolonged operative time (P < 0.05 for all). Following adjustment for potential confounders, abdominal hysterectomy was associated with greater odds of VTE than laparoscopic or vaginal approaches (adjusted odds ratio [aOR] 1.81; 95% CI 1.48-2.21 and aOR 2.31; 95% CI 1.62-3.28, respectively). Greater odds of VTE were also observed with OR time >150 minutes (aOR 1.88; 95% CI 1.46-2.42), ASA class ≥III (aOR 1.53; 95% CI 1.05-2.26), and intra- and postoperative transfusion (aOR 2.65; 95% CI 1.78-3.95 and aOR 2.98; 95% CI 1.95-4.55, respectively).

CONCLUSION: The risk of VTE is low in women undergoing hysterectomy for non-malignant indications. Blood transfusion was associated with the highest risk of VTE.