title: Tranexamic acid reduces blood loss and blood transfusion after TKA: a prospective randomized controlled trial.
abstract: BACKGROUND
  TKA may be associated with considerable blood loss, and transfusion carries substantial risk of immunologic reaction and disease transmission. Blood transfusion also involves additional cost, therefore a reduction in its use is important. Several methods reportedly reduce postoperative blood loss and avoid homologous blood transfusion with traditional TKA approaches, but it is unclear these reductions apply to a minimally invasive technique.
  
  
  OBJECTIVE
  We asked whether tranexamic acid administration could reduce blood loss and blood transfusion requirements after TKA.
  
  
  METHODS
  Between March 2008 and May 2008, we enrolled 100 patients with primary osteoarthritis undergoing a unilateral cemented TKA in a prospective, randomized, double-blind study. Patients were randomized into one of two groups: the control group received a placebo and the study group received tranexamic acid intravenously (10 mg/kg) 10 minutes before inflation of the tourniquet and 3 hours postoperatively and orally (250 mg/capsule; two capsules three times daily) for 5 days. We measured volume of drained blood 48 hours postoperatively, decrease in hemoglobin levels 12 hours postoperatively, amount of blood transfused, and number of patients requiring allogenic blood transfusion. The minimum followup was 6 months (mean, 10.4 months; range, 6-12 months).
  
  
  RESULTS
  Mean (± SD) postoperative volume of drained blood was lower in the group receiving tranexamic acid (727.50 ± 234 mL) than in control subjects (1208.77 ± 421 mL). The mean hemoglobin decrease 12 hours postoperatively was lower in patients receiving tranexamic acid (2.12 ± 0.64 g/dL) than in control subjects (3.33 ± 0.88 g/dL). The amount of blood transfused and number of patients requiring blood transfusion were lower in patients receiving tranexamic acid than in control subjects.
  
  
  CONCLUSIONS
  Tranexamic acid reduced postoperative blood loss after TKA, as reflected in reduction in the number of blood transfusions. We did not observe any change in symptomatic thromboembolic phenomenon.
  
  
  METHODS
  Level 1, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, Siriraj Hospital, Mahidol University, 2 Prannok Road, Bangkok 10700, Thailand. KeeratiC@hotmail.com
authors.forename: Keerati
authors.initials: K
authors.lastname: Charoencholvanich
authors.forename: Pichet
authors.initials: P
authors.lastname: Siriwattanasakul
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000933:Antifibrinolytic Agents / Q000008:administration & dosage*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D015415:Biomarkers / Q000097:blood; D001803:Blood Transfusion; D016009:Chi-Square Distribution; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D019106:Postoperative Hemorrhage / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013785:Thailand; D013997:Time Factors; D014148:Tranexamic Acid / Q000008:administration & dosage*; D065227:Transfusion Reaction; D016896:Treatment Outcome
chemical_list: D000933:Antifibrinolytic Agents; D015415:Biomarkers; D006454:Hemoglobins; D014148:Tranexamic Acid