BACKGROUND: To explore the efficacy of tranexamic acid (TXA) on reducing hidden blood loss (HBL) in total knee arthroplasty (TKA) by conducting a comparative study and meta-analysis.

MATERIAL AND METHODS: A total of 108 patients underwent TKA was equally distributed to experimental and control groups. The only difference between two groups was the administrations of 15 mg of TXA mixed in 100 mL normal saline for experimental group and 100 mL of normal saline for control group. The volumes of blood loss, red blood loss (RBL) were recorded, calculated and analyzed. Stata 12.0 software was applied for data analysis.

RESULTS: The intraoperative and postoperative blood loss volume in experimental group were remarkably reduced compared with those in control group (intraoperative: 105.1±12.1 mL vs. 185.5±20.3 mL, P<0.001; postoperative: 220.7±16.8 mL vs. 290.5±22.4 mL, P<0.001). Accordingly, the control group had significantly higher transfusion rate than experimental group (3.7% vs.25.9%, P=0.001). Our results also found that both the measured and hidden RBL were obviously reduced in experimental group compared with control group (measured RBL: 96.9±11.8 mL vs. 135.2±13.5 mL, P<0.001; hidden RBL: 170.8±37.2 mL vs. 364.2±41.5 mL, P<0.001). Furthermore, meta-analysis confirmed that TXA can notably decrease HBL (SMD=2.68, 95%CI=1.55~3.80, P<0.001).

CONCLUSIONS: TXA can significantly reduce the intraoperative and postoperative blood loss and HBL, therefore decreasing the transfusion need in TKA.

Keywords: Arthroplasty, Replacement, Knee - adverse effects, Blood Coagulation - drug effects, Blood Loss, Surgical - prevention & control, Blood Transfusion, Body Mass Index, Case-Control Studies, Meta-Analysis as Topic, Tranexamic Acid - therapeutic use