Preoperative Chemoprophylaxis is Safe in Major Oncology Operations and Effective at Preventing Venous Thromboembolism.

Background: We prospectively evaluated the safety and efficacy of adding preoperative chemoprophylaxis to our institution's operative venous thromboembolism (VTE) prophylaxis policy as part of a physician-led quality improvement initiative.

Study Design: Patients undergoing major cancer surgery between August 2013 and January 2014 were screened according to service-specific eligibility criteria and targeted to receive preoperative VTE chemoprophylaxis. Bleeding, transfusion, and VTE rates were compared with rates of historical controls who had not received preoperative chemoprophylaxis.

Results: The 2,058 eligible patients who underwent operation between August 2013 and January 2014 (post-intervention) were compared with a cohort of 4,960 patients operated on between January 2012 and June 2013, who did not receive preoperative VTE chemoprophylaxis (pre-intervention). In total, 71% of patients in the post-intervention group were screened for eligibility; 82% received preoperative anticoagulation. When compared with the pre-intervention group, the post-intervention group had significantly lower transfusion rates (pre- vs post-intervention, 17% vs 14%; difference 3.5%, 95% CI 1.7% to 5%, p = 0.0003) without significant difference in major bleeding (difference 0.3%, 95% CI -0.1% to 0.7%, p = 0.2). Rates of deep venous thrombosis (1.3% vs 0.2%; difference 1.1%, 95% CI 0.7% to 1.4%, p < 0.0001) and pulmonary embolus (1.0% vs 0.4%; difference 0.6%, 95% CI 0.2% to 1%, p = 0.017) were significantly lower in the post-intervention group.

Conclusions: In patients undergoing major cancer surgery, institution of a single dose of preoperative chemoprophylaxis, as part of a physician-led quality improvement initiative, did not increase bleeding or blood transfusions and was associated with a significant decrease in VTE rates.