Not all patients benefit from the postoperative antifibrinolytic treatment: clinical evidence against the universal use of tranexamic acid following total knee arthroplasty

BACKGROUND: The empirical use of tranexamic acid (TXA) for bleeding remains controversial because of the distinct fibrinolytic phenotypes observed after injury. This study sought to assess the efficacy of postoperative TXA in patients presenting with different fibrinolytic phenotypes after total knee arthroplasty (TKA). METHODS: This retrospective study included 270 patients who underwent primary TKA. The patients were divided into two groups: Group A, received no postoperative TXA, and Group B, received postoperative TXA; they were further categorized into four subgroups based on postoperative fibrinolytic phenotypes (non-fibrinolytic shutdown [NFSD] and fibrinolytic shutdown [FSD]). Fibrinolytic phenotypes were determined using percentage of clot lysis 30 min after maximum strength (LY30) level measured on postoperative day 1 (POD1). Data on perioperative hidden blood loss (HBL), decrease in the hemoglobin level (ΔHb), allogeneic blood transfusion (ABT) rate, fibrin degradation product (FDP) level, D-dimer (D-D) level, prothrombin time (PT), and activated partial thromboplastin time (APTT) as well as clinical baseline data were collected and compared. RESULTS: No differences in baseline clinical data were noted. Among patients presenting with NFSD, those in Group B had significantly lower HBL and ΔHb on POD1 and POD3 than those in Group A. Among patients presenting with FSD, perioperative HBL and ΔHb were similar between the two groups. No differences were observed in perioperative ABT rate, FDP level, D-D level, PT, and APTT. CONCLUSIONS: Patients exhibit various fibrinolytic phenotypes after TKA. Postoperative antifibrinolytic strategies may be beneficial for patients presenting with NFSD, but not for those presenting with FSD. The LY30 level may guide targeted TXA administration after TKA. However, well-designed prospective randomized controlled trials are needed to obtain more robust data.