The comparative efficacy and safety of topical and intravenous tranexamic acid for reducing perioperative blood loss in Total knee arthroplasty- A randomized controlled non-inferiority trial.

BACKGROUND: Total Knee Arthroplasty (TKA) can be associated with significant perioperative blood loss and blood transfusions. This is a prospective randomised non-inferiority trial comparing intraarticular (IA) and intravenous (IV) routes of administering Tranexamic acid (TXA) with regard to efficacy and safety.

METHODS: A total of 113 patients who underwent primary unilateral TKA from January to June 2017 randomly received either 1.5g TXA in 100mL normal saline solution (IA group, n=58) or 10mg/kg TXA (IV group, n=55) at 10min before the tourniquet inflation and at tourniquet release. Haemoglobin (Hb) drop on third day (primary outcome), visible blood loss (VBL), hidden blood loss (HBL), total blood loss (TBL), transfusion requirement, incidence of deep vein thrombosis (DVT), wound complications and renal function derangement (secondary outcomes) were recorded.

RESULTS: The mean difference in haemoglobin drop between both groups was 0.25g/dL with 90% CI of -0.07 to 0.58. Since the lower bound of 90% CI was above equivalence margin of -0.35, IA group was found to be non-inferior to IV group in terms of Hb drop. The mean difference between both groups of VBL, HBL and TBL were 0.85mL (p value 0.90), -7.9mL (p value 0.90) and -6.2mL (p value 0.93) respectively. Transfusions and wound complications were statistically insignificant. None of the patients had DVT or renal function derangement.

CONCLUSION: IA TXA is not inferior to IV TXA with regard to efficacy and safety and may be preferred considering ease of administration and lack of systemic absorption.