Prospective, randomised, controlled study on the efficacy and safety of different strategies of tranexamic acid with total blood loss, blood transfusion rate and thrombogenic biomarkers in total knee arthroplasty: study protocol.

INTRODUCTION: Total knee arthroplasty (TKA) is a common and highly effective orthopaedic procedure for treating end-stage knee osteoarthritis. Tranexamic acid (TXA) has become a routine part of perioperative care in TKAs. The best practices regarding the delivery method of TXA in TKA remain controversial. Plasminogen activator inhibitor-1 (PAI-1), thrombin-antithrombin (TAT) complexes and prothrombin fragment F1+2 (F1+2) have been demonstrated to be elevated in patients with venous thromboembolism (VTE). The aim of this trial was to investigate the most efficacious delivery method of TXA (comparison of intravenous and topical applications and comparison of three topical applications) and to evaluate the safety of TXA strategies by investigating the effect of TXA on the plasma D-dimer, PAI-1, TAT and F1+2 levels.

METHODS AND DESIGN: This trial is a prospective, randomised, controlled study that will evaluate the efficacy and safety of strategies of TXA. A total of 250 patients undergoing primary TKA will be randomly allocated to five groups for different TXA applications. The primary outcome is total blood loss. The secondary outcomes are blood transfusion rate, drainage volume, plasma D-dimer, PAI-1, TAT and F1+2 levels, maximum haemoglobin drop, wound complications, VTE and length of hospital stay.

ETHICS AND DISSEMINATION: This study's protocol is in accordance with the declaration of Helsinki. The ethics committee of the General Hospital of Ningxia Medical University approved this study (approval ID: 2020-505). The results of this study will be disseminated in international peer reviewed journals.

TRIAL REGISTRATION NUMBER: ChiCTR2000030624.