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Intra-Articular Injection of Tranexamic Acid to Reduce Blood Loss after Total Knee Arthroplasty

To the Editor: In the article by Jang et al.,1 could the authors please clarify the following: 1. A high-dose local tranexamic acid (TXA) was used in total knee arthroplasty (TKA) for postoperative blood loss reduction. What was the systemic absorption and were there any side-effects? It has been reported that a plasma concentration of TXA of only 10 mg/l is adequate for anti-fibrinolytic action2; this correlates to a concentration of 10 to 20 mg/ml for the topical TXA solution.3–5 The success rate is similar when lowor high-dose local TXA is used.6,7 Why did the authors use high-dose (1500 or 3000 mg) TXA? What are the advantages of using TXA in high concentrations? 2. The authors used high-dose intra-articular TXA, and thus the chances of systemic effects cannot be overlooked. Did the authors measure the serum TXA? 3. The authors did not use a surgical drain. In view of potential complications, such as infection, limb swelling, and joint pain, most surgeons advocate placing a drainage tube at the joint. In an emergency situation with immediate brisk blood loss, drains can be clamped without any excess morbidity.8 Please comment. 4. ‘Tissue contact time’ is the time that the TXA solution is applied to the surgical bed. This can enhance (with clamped drain) or lessen (without surgical drain) the effect. What is the authors’ opinion regarding this? 5. When high-dose TXA is used, Doppler ultrasonography should be used and plasma levels of TXA measured one hour after release of the tourniquet. 6. Randomised controlled trials are preferred for studying the effects of topical TXA to avoid bias. 7. Although the study supports the use of topical TXA for decreasing blood loss following TKA, the conclusion is perplexing regarding the dosage of TXA? What is the authors’ comment about a dosage of 1500 mg versus 3000 mg?