title: The risk-benefit profile of aprotinin versus tranexamic acid in cardiac surgery.
abstract: BACKGROUND
  Aprotinin is superior to other antifibrinolytic drugs for preventing major blood loss after cardiac surgery but may also increase perioperative mortality. It remains unclear whether its risk-benefit profile differs among low-, moderate-, and high-risk cardiac surgical patients.
  
  
  METHODS
  In this retrospective single-center cohort study, we included 15,365 patients who underwent cardiac surgery with cardiopulmonary bypass from 2000 to 2008. Of these, 1017 received aprotinin (6 x 10(6) U) and 14,358 received tranexamic acid (50-100 mg/kg). Propensity score methods were used to create a matched-pairs cohort (n = 1544) that adjusted for important between-group differences. The influence of patients' risk status on aprotinin's association with in-hospital mortality, morbidity, and blood loss was measured.
  
  
  RESULTS
  In the matched set, aprotinin was only associated with increased acute kidney injury (> 50% decrease in estimated glomerular filtration or dialysis; odds ratio 1.5; 95% confidence interval [CI] 1.1-2.1). Patients' risk status significantly influenced the associations of aprotinin with mortality, acute kidney injury, and massive blood loss (transfusion of > or = 10 U of red blood cells or need for surgical reexploration). Among high-risk patients, the respective odds ratios were 0.6 (CI 0.3-1.0), 1.1 (CI 0.7-1.7), and 0.7 (CI 0.4-1.04), and among low- to moderate-risk patients, they were 1.5 (CI 0.9-2.7), 2.2 (CI 1.4-3.5), and 1.2 (CI 0.9-1.07) (Breslow-Day test for homogeneity of odds ratios between high-risk versus low- to moderate-risk patients: P < 0.05 for all 3 outcomes).
  
  
  CONCLUSIONS
  Aprotinin tends to have a better risk-benefit profile than tranexamic acid in high-risk, but not low- to moderate-risk, patients. Its use in high-risk cases may therefore be warranted.
authors.affiliation: Department of Anesthesia, University of Toronto, and Toronto General Hospital, Toronto, ON, Canada M5G 2C4. keyvan.karkouti@uhn.on.ca
authors.forename: Keyvan
authors.initials: K
authors.lastname: Karkouti
authors.forename: Duminda N
authors.initials: DN
authors.lastname: Wijeysundera
authors.forename: Terrence M
authors.initials: TM
authors.lastname: Yau
authors.forename: Stuart A
authors.initials: SA
authors.lastname: McCluskey
authors.forename: Gordon
authors.initials: G
authors.lastname: Tait
authors.forename: W Scott
authors.initials: WS
authors.lastname: Beattie
mesh_terms: D000368:Aged; D000933:Antifibrinolytic Agents / Q000009:adverse effects* / Q000627:therapeutic use*; D007611:Aprotinin / Q000009:adverse effects* / Q000627:therapeutic use*; D016063:Blood Loss, Surgical; D006348:Cardiac Surgical Procedures / Q000401:mortality; D002315:Cardiopulmonary Bypass; D015331:Cohort Studies; D005260:Female; D006490:Hemostatics / Q000009:adverse effects* / Q000627:therapeutic use*; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011183:Postoperative Complications / Q000517:prevention & control*; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D014148:Tranexamic Acid / Q000009:adverse effects* / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000933:Antifibrinolytic Agents; D006490:Hemostatics; D014148:Tranexamic Acid; D007611:Aprotinin