Temporary clamping of drain combined with tranexamic acid reduce blood loss after total knee arthroplasty: a prospective randomized controlled trial

Background: Total knee arthroplasty (TKA) is associated with a significant blood loss. Several methods have been reported to reduce postoperative blood loss and avoid homologous blood transfusions. In this study, we investigated the efficacy of temporary clamping of the drain either or not in combination with tranexamic acid administration for controlling blood loss after TKA. Methods: The prospective, randomized, and double-blinded study was conducted in our institute. Total of 240 patients, who diagnosed primary osteoarthritis and scheduled to undergo a primary TKA,, were randomized into one of the four groups: Group A or control group, the drain was not clamped and the patient received a placebo; Group B, the drain was not clamped and the patient received tranexamic acid; Group C, the drain was clamped and the patient received a placebo; and Group D, the drain was clamped and the patient received tranexamic acid. The volume of drained blood at 48 hours postoperatively, the decreasing of hemoglobin (Hb) level at 12 hours postoperatively and the number of patients requiring blood transfusion were recorded and compared. Results: The mean postoperative volumes of drained blood and the amount of blood transfusion in the three study groups (group B, C and D) were significantly lower than those in the control group (p < 0.05), which group D had the lowest values. Furthermore, group B and D could maintain the Hb level better than group A and C (p < 0.001). In terms of blood transfusions rate, although the patients in group D required transfusion less than group A and C (p < 0.05), there was no significant difference between group D and B. The relative risks for transfusion requirement were 4.4 for group A, 1.4 for group B and 3.0 for group C when compared to group D. Conclusions: The clamping of drain combined with tranexamic acid administration could reduce postoperative blood loss and blood transfusion after TKA, significantly greater than using tranexamic acid or drain clamping alone.