Abstract
There is no consensus regarding the ideal dosages and times of multiple-dose intravenous
tranexamic acid (IV-TXA) administration in total knee arthroplasty (TKA). This study
aimed to assess the effect of six-dose IV-TXA with the total dosage more than 6 g
on postoperative fibrinolysis and hidden blood loss (HBL) after primary TKA. A total
of 175 patients were randomized into three groups to receive placebo (group A), or
a single preoperative dose of 20 mg/kg IV-TXA (group B), or six-dose IV-TXA from the
beginning of the procedure to subsequent 24 hours with the total dosage more than
6 g (group C). The calculated HBL, maximum hemoglobin (Hb) drop, transfusion rate,
and the incidence of thromboembolic events were compared among groups. The levels
of fibrinolysis parameters in plasma including fibrin(-ogen) degradation products
(FDP) and D-dimer were measured at six time points from preoperatively to 3-month
postoperative period. The mean HBL and maximum Hb drop in group C (515.51 ± 245.79 mL,
and 2.06 ± 0.73 g/dL, respectively) were significantly lower than those in groups
B (756.06 ± 226.79 mL, p < 0.001; and 2.77 ± 0.78 g/dL, p < 0.001, respectively) and A (987.65 ± 275.38 mL, p < 0.001; and 3.49 ± 0.86 g/dL, p < 0.001, respectively). Such differences were also detected between groups A and
B (p < 0.001 and p < 0.001, respectively). The levels of FDP and D-dimer in plasma were lower in group
C than those in groups B and A on postoperative 24, 48, 72 hours (p < 0.001 for all). No episode of transfusion occurred, and the incidence of thromboembolic
events were similar among groups (p > 0.05). The administration of six-dose IV-TXA during the first 24 hours resulted
in reduced HBL following TKA without a measured increase in thromboembolic events.
Keywords tranexamic acid - fibrinolysis - hidden blood loss - total knee arthroplasty - randomized
controlled trial
