Comparison of different modes of tranexamic acid administration in patients undergoing total knee arthroplasty.

Tranexamic acid. Patients will be assigned to one of 2 treatment groups: 1. Group 1 (Intra-articular TXA group) will receive 100 ml of Saline intravenously, 5 minutes before incision, 3000mg (30ml) of TXA injected in to the knee joint after wound closure and two doses of 100 ml of Saline intra-venously at 8 hourly intervals post-operatively. 2. Group 2 (Intravenous TXA group) will receive 1000mg of TXA in 100ml Saline intravenously 5 minutes before incision and 30ml of Saline injected in to the knee joint after wound closure to make the group comparative with Group 1 and also provide a tamponade effect. Another 1000mg dose of TXA (in 100ml Normal Saline over 15 minutes) will be repeated at 8 hourly intervals post-operatively for another two doses. Patients undergoing primary total knee arthroplasty will be invited to take part in the study and informed written consent will be obtained from willing participants. Patients undergoing bilateral TKA, those with history of thromboembolic events (deep vein thrombosis, pulmonary embolism or cerebrovascular accident), renal dysfunction (plasma Creatinine level >130 mmol/L) or coagulopathy (INR > 1.4) will be excluded. Also patients with pre-operative anemia (Hb < 120 for females and Hb < 130 for males) will be excluded.