INTRODUCTION

Total knee arthroplasty (TKA) surgery can be associated with significant blood loss. Among the problems associated with such blood loss is the need for transfusions of banked blood [1]. Transfusions not only have a financial consequence but also carry a small risk of disease transmission to the patient. Antifibrinolytics have been successfully used to reduce transfusion requirements in elective arthroplasty patients. The objective of this meta-analysis is to determine which of tranexamic acid (TXA) and epsilon-aminocaproic acid (EACA) is more effective for reducing peri-operative blood loss, and lessening the need for blood transfusion following knee arthroplasty surgery.

MATERIALS AND METHODS

MEDLINE, Embase and CINAHL databases were searched for relevant articles published between January 1980 to January 2018 for the purpose of identifying studies comparing TXA and EACA for TKA surgery. A double-extraction technique was used, and included studies were assessed regarding their methodological quality prior to analysis. Outcomes analysed included blood loss, pre- and post-operative haemoglobin, number of patients requiring transfusion, number of units transfused, operative and tourniquet time, and complications associated with antifibrinolytics.

RESULTS

Three studies contributed to the quantitative analysis of 1691 patients, with 743 patients included in the TXA group and 948 in the EACA group. Estimated blood loss was similar between the two groups [95% confidence interval (CI) -0.50, 0.04; Z = 1.69; P = 0.09]. There were no differences between the two groups regarding the percentage of patients requiring transfusion (95% CI 0.14, 4.13; Z = 0.31; P = 0.76). There was no difference in the pre- and post-operative haemoglobin difference between the two groups (95% CI -0.36, 0.24; Z = 0.38; P = 0.70). There was no difference in the average number of transfused units (95% CI -0.53, 0.25; Z = 0.71; P = 0.48). There was no difference in the operative (95% CI -0.35, 0.36; Z = 0.04; P = 0.97) or tourniquet time (95% CI -0.16, 0.34; Z = 0.72; P = 0.47). Similarly, there was no difference in the percentage of venous thromboembolism between the two groups (95% CI 0.17, 2.80; Z = 0.51; P = 0.61).

CONCLUSIONS

This study did not demonstrate TXA to be superior to EACA. In fact, both antifibrinolytic therapies demonstrated similar efficacy in terms of intra-operative blood loss, transfusion requirements and complication rates. Currently EACA has a lower cost, which makes it an appealing alternative to TXA for TKA surgery.

LEVEL OF EVIDENCE