Tranexamic Acid Reduces Blood Loss and Transfusion Rate in Obese Patients Undergoing Total Joint Arthroplasty

Background: The aim of this study was to evaluate the effect of Tranexamic Acid 3 (TXA) on haematocrit, hemoglobin levels, and packed red blood cell (pRBC) 4 transfusions in obese patients undergoing total joint arthroplasty (TJA). 5 6 Material and Methods: Between January and December 2014, 117 consecutive 7 primary TJAs with BMI ≥ 30 were identified from our prospective database 8 (THA=23; TKA=94). TXA was utilized in 45 (38.5%) TJAs (study group) and was 9 compared to a consecutive series of 72 (61.5%) TJAs (control group). Low-risk 10 patients (ASA I or II) received Aspirin 325 mg, twice a day; otherwise low-molecular 11 weight heparin was used to DVT prophylaxis. Transfusion thereshold was 12 haematocrit < 25% or hemoglobin level of < 8.0 g/dl. Changes in hemoglobin and 13 haematocrit levels, number of pRBC transfusions, and thrombolytic events were 14 recorded. 15 16

Results: The changes in haematocrit (4.5% vs. 9.7%) and hemoglobin levels (2.7 g/dl 17 vs. 3.6 g/dl) were significantly less for the study group than the control group 18 (p<0.001). 21 patients (29.1%) in the control group required a pRBC transfusion, 19 whereas only 5 patients (11.1%) in the study group required transfusion (p=0.023). In 20 morbid obesity patients (BMI >40), blood transfusion decreased from 27.3% to 21 14.3%. No thrombolytic events were noted in the study group. 22 23

Conclusion: The use of TXA in obese patients undergoing total joint arthroplasty 24 significantly reduced drop in haematocrit and hemoglobin levels as well as pRBC 25 transfusion rate.