The value of tranexamic acid for patients with preoperative anemia in primary total knee arthroplasty.

BACKGROUND: Preoperative anemia is relatively common in patients undergoing primary total knee arthroplasty (TKA), and is associated with higher medical costs due to blood transfusions. METHODS: We aimed to discuss the efficiency of tranexamic acid (TXA) administration for blood loss control in preoperatively anemic patients undergoing primary TKA. We retrospectively reviewed the clinical data regarding a consecutive series of primary unilateral TKA patients with preoperative anemia. Patients were divided into TXA group (received TXA peri-operatively) and control group (did not receive TXA). Outcome measures included drainage volume; hemoglobin, and hematocrit levels recorded preoperatively and over the first 5 days postoperatively; amount of allogeneic blood transfusion; and prevalence of thrombosis. RESULTS: Ninety-six patients from 996 cases were included in the study. Demographics, general health condition, and preoperative conditions were comparable between the two groups. However, significantly lower drainage volume (P < 0.001), hidden blood loss (P < 0.001), and allogeneic blood transfusion volume (χ = 4.00, P = 0.046) were noted in TXA group. The hemoglobin and hematocrit levels were significantly higher in TXA group on the first postoperative day (P = 0.006), but overall the drop in hemoglobin and hematocrit levels over the first 5 days postoperatively was similar between the groups (P = 0.763), as was the incidence of thromboembolism events (P = 0.794). CONCLUSION: TXA has a positive role for patients with preoperative anemia in primary total knee arthroplasty. In patients with mild preoperative anemia, TXA decreases hidden blood loss and the need for allogeneic blood transfusion, which mainly appears effective on the first postoperative day of TKA.