title: Preoperative Aspirin Use and Lung Injury After Aortic Valve Replacement Surgery: A Retrospective Cohort Study.
abstract: BACKGROUND
  Acute respiratory distress syndrome (ARDS) occurs uncommonly after cardiac surgery but has a mortality rate as high as 80%. Aspirin may prevent lung injury in at-risk patients by reducing platelet-neutrophil aggregates in the lung. We hypothesized that preoperative aspirin use would be associated with a decreased risk of ARDS after aortic valve replacement surgery.
  
  
  METHODS
  We performed a retrospective single-center cohort study that included all adult patients who had aortic valve replacement surgery during a 5-year period. The primary outcome variable was postoperative ARDS. The secondary outcome variable was nadir PaO2/FIO2 ratio during the first 72 hours after surgery. Both crude and propensity score-adjusted logistic regression analyses were performed to estimate the odds ratio for developing ARDS in aspirin users. Subgroups were analyzed to determine whether preoperative aspirin use might be associated with improved oxygenation in patients with specific risk factors for lung injury.
  
  
  RESULTS
  Of the 375 patients who had aortic valve replacement surgery during the study period, 181 patients took aspirin preoperatively (48.3%) with most taking a dose of 81 mg (72.0%). There were 22 cases of ARDS in the cohort (5.5%). There was no significant difference in the rate of ARDS between aspirin users and nonusers (5.0% vs 6.7%, P = 0.52). There was also no significant difference in the nadir PaO2/FIO2 ratio between aspirin users and nonusers (P = 0.12). The crude odds ratio for ARDS in aspirin users was 0.725 (99% confidence interval, 0.229-2.289; P = 0.47), and the propensity score-adjusted odds ratio was 0.457 (99% confidence interval, 0.120-1.730; P = 0.13).
  
  
  CONCLUSIONS
  Within the constraints of this analysis that included only 22 affected patients, preoperative aspirin use was not associated with a decreased incidence of ARDS after aortic valve replacement surgery or improved oxygenation.
authors.affiliation: From the Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Michael
authors.initials: M
authors.lastname: Mazzeffi
authors.forename: Woderyelesh
authors.initials: W
authors.lastname: Kassa
authors.forename: James
authors.initials: J
authors.lastname: Gammie
authors.forename: Kenichi
authors.initials: K
authors.lastname: Tanaka
authors.forename: Philip
authors.initials: P
authors.lastname: Roman
authors.forename: Min
authors.initials: M
authors.lastname: Zhan
authors.forename: Bartley
authors.initials: B
authors.lastname: Griffith
authors.forename: Peter
authors.initials: P
authors.lastname: Rock
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery*; D001241:Aspirin / Q000008:administration & dosage*; D015142:Baltimore; D004334:Drug Administration Schedule; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects*; D006801:Humans; D016015:Logistic Models; D008168:Lung / Q000187:drug effects / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D057216:Propensity Score; D012128:Respiratory Distress Syndrome / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin