RESUMO
OBJECTIVES: Surgical bleeding. transfusion rate and cardiovascular complications were analized in patients undergoing chronic treatment with low-doses aspirin and scheduled to unilateral primary knee arthroplasty. PATIENTS AND METHODS: We retrospectively studied 117 patients between 2005 and 2006 scheduled for elective knee replacement that received antiplatelet therapy with aspirin (100mg/day). Aspirin medication was maintained or discontinued preoperatively according to medical criteria. We analyzed the biological, clinical and anesthetic data, blood-saving techniques used, surgical bleeding, allogeneic blood transfusion rate, cardiocirculatory complications (myocardial, cerebral or peripheral ischemia), hospital stay and mortality. This population was compared with 190 patients (control group) who underwent the same operation at the same time interval but did not receive aspirin therapy. RESULTS: The aspirin-treated group was significantly older, with higher weight and poorer health state (higher incidence of ischemic heart disease, cerebral ischemia and diabetes). The hidden and external surgical bleeding and transfusion rate were similar if the aspirin were interrupted or not, preoperatively. Bleeding and transfusion rates were independent of time of interruption of the aspirin. Hospital mortality was zero in the 2 groups. A acute myocardial infarction and a transient stroke happened in two patients wich aspirin treatment was discontinued. CONCLUSIONS: Preoperative treatment with low doses of aspirin does not increase surgical bleeding and transfusion rate in total knee arthroplasty. Preoperative discontinuation can cause severe cardiocirculatory complications.