Predicting Factors for Allogeneic Blood Transfusion and Excessive Postoperative Blood Loss after Single Low-Dosage Intra-Articular Tranexamic Acid Application in Total Knee Replacement

Background. Recently, intra-articular tranexamic acid (IA-TXA) application has become a popular method for perioperative blood loss (PBL) reduction in total knee replacement (TKR). Nevertheless, through our knowledge, no previous studies had shown the correlation perioperative factors and the risk of excessive PBL or need of blood transfusion (BT) after IA-TXA. Materials and Methods. A retrospective study was conducted in patients underwent 299 primary TKRs, using IA-TXA, during 2-year period (2013-2014). Patient's characteristic and perioperative data were reviewed and collected. PBL was measured as total hemoglobin loss (THL), estimated total blood loss (ETBL), and drainage volume per kg (DV/kg). Excessive PBL was defined as PBL that exceeded 90th percentile. Results. From multivariate analysis, low preoperative hemoglobin (Hb) level and body mass index (BMI) were the significant predictors of postoperative BT (p < 0.0001 and 0.003, resp.). Excessive THL significant associated with preoperative Hb (p < 0.0001). Excessive ETBL significantly associated with preoperative Hb, height, preoperative range-of-motion, and creatinine clearance (p < 0.05 all). Low BMI and large prosthesis size were the significant predictors of excessive DV/kg (p = 0.0001 and 0.002, resp.). Conclusions. Low preoperative Hb and BMI were the significant risks of postoperative transfusion after TKR with IA-TXA. Moreover, multiple perioperative factors could result in higher PBL.