Does aspirin have a role in venous thromboembolism prophylaxis in total knee arthroplasty patients?

The objectives of this study were to compare the risk of venous thromboembolism (VTE), bleeding, surgical site infection, and mortality in patients receiving aspirin or guideline-approved VTE prophylactic therapies (warfarin, low-molecular-weight heparins, synthetic pentasaccharides) in total knee arthroplasty (TKA). We analyzed clinical and administrative data from 93,840 patients who underwent primary TKA at 307 US hospitals over a 24-month period. Fifty-one thousand nine hundred twenty-three (55%) patients received warfarin, 37,198 (40%) received injectable agents, and 4719 (5%) received aspirin. After adjustment for patient and hospital factors, patients who received aspirin VTE prophylaxis (VTEP) had lower odds for thromboembolism compared to warfarin patients but with similar odds compared with injectable VTEP; there were no differences in risk of bleeding, infection, or mortality after adjustment. Our results suggest that aspirin, when used in conjunction with other clinical care protocols, may be effective VTEP for certain TKA patients.