Inpatient Enoxaparin and Outpatient Aspirin Chemoprophylaxis Regimen After Primary Hip and Knee Arthroplasty: A Preliminary Study

Our institution has used a thromboprophylaxis regimen consisting of inpatient enoxaparin and outpatient aspirin for patients at standard risk for venous thrombosis after hip and knee arthroplasty. We reviewed 500 cases using this protocol. Inpatient treatment with enoxaparin averaged 2.75 days, followed by a 28-day course of aspirin. The overall thrombosis rate was 0.6% (1 deep venous thrombosis and 2 pulmonary emboli). Bleeding requiring transfusion of 3 or more units of packed red blood cells occurred in 1.8% of the cases. Fifteen infections were noted, 14 superficial and 1 deep. This compared favorably with a control group of 500 patients using a 14-day course of enoxaparin followed by 14 days of aspirin. We believe that a brief course of inpatient enoxaparin and outpatient aspirin is a safe and effective form of thromboprophylaxis.