Postoperative blood loss reduction in computer-assisted surgery total knee replacement by low dose intra-articular tranexamic acid injection together with 2-hour clamp drain: a prospective triple-blinded randomized controlled trial.

A high-dose local tranexamic acid has been introduced in total knee arthroplasty for bleeding control. We are not sure about the systemic absorption and side effects. The aim of this study was to evaluate the effect of low dosage of intra-articular tranexamic acid injection combined with 2-hour clamp drain in minimally bleeding computer-assisted surgery total knee replacement (CAS-TKR). A prospective randomized controlled trial was conducted in a total of 48 patients underwent CAS-TKR. The patients were randomly assigned to receive either of a mixed intra-articular solution of tranexamic acid 250 mg with physiologic saline (TXA group), or physiologic saline (control group) and then followed by clamp drain for 2 hours. Postoperative blood loss was measured by three different methods as drainage volume, total hemoglobin loss and calculated total blood loss. Transfusion requirement and postoperative complications were recorded. All patients were screened for deep vein thrombosis and the functional outcomes were evaluated at 6 months after surgery. The mean postoperative drainage volume, total hemoglobin loss and calculated total blood loss in TXA group were 308.8 mL, 2.1 g/dL and 206.3 mL compared to 529.0 mL, 3.0 g/dL and 385.1 mL in the control group (P=0.0003, 0.0005 and <0.0001 respectively). Allogenic blood transfusion was needed for one patient (4.2%) in TXA group and for eight patients (33.3%) in the control group. Postoperative knee scores were not significantly different between groups. No deep vein thrombosis, infection or wound complication was detected in both groups. In this study, low dose intra-articular tranexamic acid injection combined with 2-hour clamping drain was effective for reducing postoperative blood loss and transfusion requirement in CAS-TKR without significant difference in postoperative complications or functional outcomes.