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[A PROSPECTIVE RANDOMIZED SELF-CONTROLLED STUDY ON EFFECT OF TRANEXAMIC ACID IN REDUCING BLOOD LOSS IN TOTAL KNEE ARTHROPLASTY].

OBJECTIVE
To investigate the safety and efficiency of intravenous tranexamic acid (TXA) to reduce blood loss in total knee arthroplasty (TKA).


METHODS
A prospective, randomized, self-controlled study was carried out on 60 patients scheduled for bilateral TKA between January 2012 and December 2013. TXA (10 mg/kg) was injected intravenously approximately 10 minutes before tourniquet release when TKA was performed on one side (TXA group), and TXA was not used on the other side (control group). No significant difference was found in the preoperative hemoglobin (Hgb), platelet (PLT) count, prothrombin time (PT), and activated partial thromboplastin time (APTT) between 2 groups (P > 0.05). The amount of drainage, the total blood loss, the hidden blood loss, the postoperative Hgb, the amount of blood transfusion, the ratio of blood transfusion, and the incidence of vein thrombosis embolism (VTE) were compared between 2 groups.


RESULTS
The amount of drainage and total blood loss were significantly less in the TXA group than in control group (P < 0.05), and the Hgb was significantly lower in the control group than in the TXA group at 6 hours, 1, 3, and 7 days after operation (P < 0.05). There was no significant difference in the hidden blood loss between 2 groups (t = 1.157, P = 0.252). The ratio of blood transfusion was significantly less in TXA group (6.7%, 4/60) than in control group (21.7%, 13/60)(P = 0.034). The total amount of blood transfusion was 14 units in TXA group, which was significantly less than that of control group (38 units) (P = 0.004). Deep vein thrombosis occurred in 3 cases in 2 groups respectively, showing no significant difference (P = 1.000). There was no symptomatic pulmonary embolism. All patients were followed up for 8-17 months, with an average of 13.7 months. No new VTE case was found during the follow-up period.


CONCLUSION
Intravenous injection of TXA (10 mg/kg) at 10 minutes before tourniquet release in TKA is effective in reducing perioperative blood loss, amount of blood transfusion, and ratio of transfusion, and it will not increase the risk of VTE.