Cost comparison of strategies for the management of venous thromboembolic event risk following laparotomy for ovarian cancer

Objective: To evaluate the costs and effectiveness of thromboprophylaxis strategies following laparotomy for ovarian cancer. Methods: We constructed a decision model to evaluate six strategies for management of postoperative venous thromboembolism (VTE) risk: (1) no thromboprophylaxis; (2) inpatient sequential compression device (SCD); (3) inpatient unfractionated heparin (UFH) 5000 units TID; (4) inpatient low molecular weight heparin (LMWH) 40 mg daily; (5) UFH 5000 units TID × 1 month; (6) LMWH 40 mg daily × 1 month. Rates of VTE, heparin-induced thrombocytopenia, and significant bleeding for each strategy were obtained from published literature. Costs were based on institutional charges or obtained from the Agency for Healthcare Research and Quality Nationwide Inpatient Sample database for 2008 and average wholesale pricing. Sensitivity analyses were performed to account for uncertainty in estimates. Results: In the base case, UFH × 1 month was the least expensive (mean cost $1611) and most effective (VTE risk 1.9%) strategy. LMWH × 1 month was equally effective but more expensive ($2197). Inpatient UFH, inpatient LMWH, and SCDs were less effective and more expensive than UFH × 1 month. In the sensitivity analysis, cost rankings remained unchanged unless the baseline probability of VTE was assumed < 6.5%, the cost of VTE treatment was < $20,000, or the cost of bleeding was > $4500. LMWH × 1 month became least expensive when cost was decreased 38%. Conclusion: Based on current evidence, extended prophylaxis with UFH is the least expensive and most effective strategy to prevent postoperative VTE following laparotomy for ovarian cancer.