title: [Local application of tranexamic acid reduces blood less in unilateral total knee arthroplasty: a retrospective comparison analysis].
abstract: OBJECTIVE
  To investigate the efficacy and safety of tranexamic acid in patients who receiving unilateral total knee arthroplasty (TKA).
  
  
  METHODS
  From March 2011 to March 2012, clinical data of 95 patients who received primary unilateral TKA were analyzed retrospectively, including 23 male and 72 female patients, age from 60 to 87 years, mean (71 ± 4) years. The patients in treatment group received 0.5 g of tranexamic acid inside knee joint after capsule closure, and patients in control group did not receive tranexamic acid. Two groups of patient's age, height, weight and disease diagnosis and other parameters of the differences were no statistical significance (P > 0.05). The amounts of intraoperative blood loss, postoperative visible blood loss, the hidden blood loss, and blood transfusion, the number of patients needing blood transfusion, symptoms of deep venous thrombosis and lower extremity ecchymosis were observed. The values of preoperative and 3 hours of postoperative D-dimer and related coagulation markers were recorded. Group t test was used to compare between the two groups.
  
  
  RESULTS
  There were no significant differences in intraoperative blood loss (P > 0.05). The amounts of postoperative visible blood loss, the hidden blood loss was significant different (t = 17.51 and 64.18, P < 0.05). Transfusion of both groups were (470 ± 150) ml and (708 ± 245) ml. The value of postoperative hemoglobin and hematocrit was lower in control group as compared with those in treatment group (t = -18.88 and -13.05, P < 0.05). No deep venous thrombosis was observed through Doppler ultrasound examination. Postoperative 3 hours D-dimer in the two groups for (0.91 ± 0.44) and (1.21 ± 0.65) mg/L, were significantly higher than that of preoperative (0.36 ± 0.11) and (0.37 ± 0.14) mg/L, with a statistically significant difference (t = 5.40 and 44.68, P < 0.05), and the control group was higher than treatment group (t = 1.99, P < 0.05). There was not statistically significant difference between the coagulation indicators of the two groups.
  
  
  CONCLUSIONS
  The local application of tranexamic acid intraoperatively in unilateral TKA patients could significantly reduce the amounts of postoperative blood loss and blood transfusion to avoid TKA patients' perioperative anemia-related complications. It is also safe, ecnomic and easy to use during surgery.
authors.affiliation: Department of Joint Surgery & Sport Medicine, the First Affiliated Hospital of People Liberation Army General Hospital, Beijing 100048, China.
authors.forename: Yun-qing
authors.initials: YQ
authors.lastname: Ma
authors.forename: Yi-chao
authors.initials: YC
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000933:Antifibrinolytic Agents / Q000627:therapeutic use*; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019106:Postoperative Hemorrhage / Q000517:prevention & control*; D012189:Retrospective Studies; D014148:Tranexamic Acid / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000933:Antifibrinolytic Agents; D014148:Tranexamic Acid