Cost-effectiveness of combination thromboembolism prophylaxis in gynecologic oncology surgery

OBJECTIVE: To compare the cost-effectiveness of external pneumatic compression devices with and without the addition of low-molecular-weight heparin for the prevention of deep vein thrombosis in high-risk surgical patients with gynecologic cancer. METHODS: A Markov decision analytic model was used to estimate the costs and outcomes associated with the prophylactic use of external pneumatic compression with and without low-molecular-weight heparin in patients undergoing gynecologic surgery. We estimated cost per fatal pulmonary embolus prevented, cost per deep vein thrombus prevented, and cost per life-year saved. Probability estimates for various outcomes and efficacies were obtained from the literature, using data specific for gynecologic surgery patients when available. RESULTS: In the base case scenario, cost-effectiveness estimates for combination prophylaxis varied from 10,091 dollars per life-year saved for a 35-year-old patient with IB cervix cancer patient to 50,181 dollars for a 65-year-old patient with stage IIIC ovarian cancer, costs within the 50,000-65,000 dollars per life-year saved threshold considered to be cost-effective. Combination prophylaxis appeared to be cost-effective in gynecologic oncology patients as long as the risk of perioperative thromboembolism using this method of prevention was less than or equal to 4%. Sensitivity analysis indicated that variation of the marginal cost of low-molecular-weight heparin and the marginal effectiveness to extremes did not change the conclusions of the statistical model. CONCLUSION: The use of combination therapy external pneumatic compression is estimated to be cost-effective for high-risk gynecologic oncology patients undergoing surgery. Clinical trials to determine the efficacy of perioperative combination therapy in gynecologic surgery are justified.