RANDOMISED CONTROLLED TRIAL OF THE USE OF TOPICAL APPLICATION OF TRANEXAMIC ACID IN PRIMARY TOTAL KNEE REPLACEMENT

Abstract

Introduction: Today’s aging population has resulted in an increase in the number of major orthopaedic surgical interventions in the elderly. Total knee replacement (TKR) is one of the commonest operations in orthopaedic practice. The fourth annual report of the National Joint Registry showed that there were 60 986 TKR performed in England and Wales in 2006. The true figure is probably much higher. Literature showed that 20–70% of patients who had TKR needed 1–3 units of blood.

Although safer than ever, allogeneic transfusion is still associated with risks for the recipient (haemolysis, infection, immunosuppression, transfusion-related acute lung injury and even death).

Tranexamic acid (TA) is a synthetic antifibrinolytic agent that has been successfully used to stop bleeding after dental operation, removal of tonsils, prostate surgery, heavy menstrual bleeding, eye injuries and in patients with Haemophilia.

In this study Tranexamic acid was applied topically to the exposed tissue around the knee joint prior to the wound closure and tourniquet release. It is anticipated that this method of administration is quick, easy, associated with less systemic side effect. Also, it provides a higher concentration of the Tranexamic acid at the bleeding site.

Objectives: To find out whether Tranexamic acid can reduce blood loss and subsequent blood transfusion significantly after total knee replacement when applied topically without extra side effects.

Design: A double blind randomised controlled trial of 150 patients who underwent unilateral primary cemented total knee replacement. This number gives a 90% power to detect a 50% reduction in blood loss and 80% power to detect a reduction in blood transfusion from current local standard 30% to 10%.

Outcome Measures: Blood loss, transfusion, Length of stay, complications, Euroqol and Oxford Knee Score.

Results: The two groups were comparable in age, weight, height, BMI, Tourniquet time, and type of anaesthesia. There has been significant differences in the amount of blood loss and blood transfusion in favour of tranexamic acid (p-values are 0.001 and 0.007 respectively). Fourteen patients needed blood transfusion ranged from 2–6 units. Thirteen were in the Placebo group and only one in the Tranexamic acid. There has been no significant difference among other outcomes in particular complications rates such as DVT and pulmonary embolism.