Evaluating Blood Loss and the Effect of Antiplatelet Treatment in Foot and Ankle Amputations

The interrelationship between diabetes mellitus and cardiovascular disease is well-documented, and, secondary to the latter, is the use of antiplatelet therapy. Although diabetes and the associated vascular manifestations are driving forces behind lower extremity amputations, few data are available on the risks of perioperative antiplatelet therapy with foot and ankle amputations. The goal of the present study was to address the surgical effect of continuing or discontinuing antiplatelet therapy before foot and/or ankle amputation. The following data were retrospectively collected: blood loss, pre- and postoperative hematocrit and hemoglobin, operative time, amputation type, age, diabetic status, antiplatelet treatment, and number of transfusions during the perioperative period. Perioperative antiplatelet therapy was defined as exposure to aspirin or clopidogrel within 3 days before surgery. To compare the outcomes between groups, the following factors were analyzed using bivariate analyses and then multivariate regression models: (1) the need for transfusions, (2) high blood loss (>20 mL), (3) volume of blood loss, and (4) operative time. The noninferiority of continued antiplatelet use was assessed in terms of operative time and blood loss, using a noninferiority margin of 10 minutes or 10 mL, respectively. Antiplatelet therapy was not a statistically significant risk factor for any of the studied outcomes on multivariate analysis. Equivalence testing revealed that continuing antiplatelet therapy is not inferior to discontinuing perioperative therapy in terms of blood loss and operative time. Multivariate analysis of the data suggested that antiplatelet therapy has no statistically significant impact on blood loss, transfusion rate, or operative time.