Perioperative Management of Patients on Oral Anticoagulants: A Decision Analysis

Background . To better inform clinicians on the optimal management of patients on oral anticoagulation who need to undergo surgery or invasive procedures, the authors performed a decision analysis examining whether a perioperative aggressive or minimalist strategy results in greater quality-adjusted survival. Methods . A decision analysis model was created comparing withholding warfarin (minimalist strategy) to withholding warfarin and administering treatment-dose subcutaneous low-molecular-weight heparin (LMWH) or intravenous heparin perioperatively (aggressive strategy). The base-case analysis examined a hypothetical 60-year-old hypertensive individual with mechanical aortic valve replacement undergoing major abdominal surgery. A probabilistic sensitivity analysis was performed using a Monte Carlo simulation with quality-adjusted life expectancy (QALE) as the outcome. Secondary analyses examined patients with a mechanical mitral valve and atrial fibrillation. Sensitivity analyses were performed for each variable. Results . Under the base-case scenario, the minimalist strategy was preferred for 78% of trials in the Monte Carlo simulation, with a mean benefit of 0.003 years (95% confidence interval, -0.005 years to 0.011 years). Sensitivity analyses based on point estimates indicate that the aggressive strategy is preferred when the annual stroke rate is >5.6% or the increase in postoperative major bleeding induced by heparin is