Comparative Efficacy and Safety of Intravenous vs. Combined Intravenous and Intraarticular Tranexamic Acid Administration in Total Knee Arthroplasty: A Stratified Analysis Based on Bleeding Risk.

Objectives: Tranexamic acid (TXA) effectively reduces blood loss in total knee arthroplasty (TKA) without raising thromboembolism risk, though the best administration route is still debated. This study aimed to classify patients based on bleeding risk factors and determine whether intravenous (IV) alone or combined IV and intraarticular (IA) administration of TXA provides the greatest benefit. Methods: This study included 200 patients who underwent TKA, with 100 patients with IV administration only and 100 with combined IV and IA administration. The bleeding risk stratification criteria were based on patient body mass index, age, the use of increased anticoagulant doses in patients with atrial fibrillation, and cases where synovectomy was performed. The primary outcomes measured were tube drainage volume, hemoglobin (Hb) and hematocrit (Ht) levels, and blood transfusion rates. Secondary outcomes included wound complications, symptomatic deep vein thrombosis (DVT), and symptomatic pulmonary embolism (PE). Results: Combined IV and IA administration showed better outcomes in terms of Hb reduction (difference of 0.98 g/dl, 95%CI: 0.69 to 1.26, P<0.0001), Ht reduction (difference of 2.66%, 95% CI: 1.78 to 3.54, P<0.0001), tube drainage (294 vs 358 ml, 95% CI: 11.58 to 115.93, P=0.0170) and shorter hospitalization stay (difference of 0.53 days, 95% CI: 0.16 to 0.90, P=0.0050) compared to only IV administration. Patients who underwent synovectomy had lower tube drainage with combined TXA administration compared to IV only (355.42 ± 161.68 ml vs. 429.79 ± 268.48 ml). Neither group experienced any cases of symptomatic (i.e. DVT) or pulmonary embolism (PE). Conclusion: The combined administration of TXA (IV and IA) in patients undergoing TKA was more effective than IV-only administration.