Repeat-dose intravenous tranexamic acid further decreases blood loss in total knee arthroplasty

Tranexamic acid (TXA) reduces blood loss in patients undergoing total knee arthroplasty (TKA). However, few studies have reported the optimum timing and dosage for administration of TXA. The purpose of this study was to evaluate the effect of repeat-dose TXA on blood loss during TKA and the necessity of autologous blood donation or postoperative autotransfusion. We enrolled 78 patients with primary osteoarthritis undergoing cemented TKAs. Consecutive patients were divided into three groups, as follows: control group (n = 31), single-TXA group (n = 21) in whom TXA (1,000 mg) was intravenously administered 10 min before deflation of the tourniquet, and twice-TXA group (n = 26) in whom TXA (1,000 mg) was intravenously administered 10 min before deflation of the tourniquet and 3 h after the operation. We measured the volume of drained blood after the operation. Haemoglobin (Hb) levels were measured at days 1, 4 and 7 postoperation. Venous thromboembolic events (VTE) were screened using compression ultrasonography at enrollment and 1 and 7 days after operation. The mean volume of drained blood after the operation was lower in the twice-TXA group than in the single-TXA (p < 0.001) and control (p < 0.0001) groups. No significant differences were observed in the incidence of VTE between these groups. Administration of TXA twice reduced postoperative blood loss after TKA, and TXA was not associated with the risk of deep-vein thrombosis (DVT) or pulmonary embolism (PE). Further, administration of TXA twice may eliminate the need for blood transfusion during TKA.