[Effectiveness of tranexamic acid in routine performance of total knee replacement surgery]

To evaluate the effectiveness of treatment with tranexamic acid, compared to absence of antifibrinolytic treatment, in reducing transfusion rates and the number of units of packed red blood cells required in patients undergoing total knee replacement surgery.

We reviewed the medical records of all patients who underwent total knee replacement surgery in a general hospital in 2006. Information was recorded on treatment with tranexamic acid, use of other antifibrinolytic drugs, hemoglobin and hematocrit levels before surgery and 3 days after surgery, patients requiring transfusions, units of packed red blood cells administered, and whether or not drains were clamped within 4 hours. Complications attributable to tranexamic acid (thromboembolic or systemic complications) and preoperative treatment with erythropoietin were also recorded.

Data for 166 patients were analyzed. Of these, 120 (72.3%) received tranexamic acid, 15 (9%) received epsilon-aminocaproic acid, and 31 (18.7%) received no antifibrinolytic treatment. Transfusions were given to 17 patients, of whom 6 (5.0%) had received tranexamic acid, 2 (133%) had received epsilon-aminocaproic acid, and 9 (29.0%) had received no antifibrinolytic treatment. The mean numbers of packed red blood cell units transfused in each group were as follows: 0.075 in the tranexamic acid group, 0.200 in the epsilon-aminocaproic acid group, and 0.645 in the group with no antifibrinolytic treatment (P < .001). The mean decrease in hemoglobin levels 5 days after surgery was 3.04 g/dL in the tranexamic acid group, 3.55 g/dL in the epsilon-aminocaproic acid group and 3.76 g/dL in the group with no antifibrinolytic treatment (P < .001).

Tranexamic acid is effective in reducing the percentage of patients requiring transfusions and in the number of units of packed red blood cells required in total knee replacement surgery. No complications attributable to this treatment were found.