title: Associations between preoperative anemia and outcomes after off-pump coronary artery bypass grafting.
abstract: BACKGROUND
  It is still unclear whether patients with preoperative anemia have worse outcomes after coronary artery bypass grafting (CABG) than patients without preoperative anemia. The aim of this study was to assess differences in outcomes between patients with and without preoperative anemia who underwent off-pump CABG.
  
  
  METHODS
  A total of 1,123 patients who underwent isolated off-pump CABG between September 2004 and December 2010 were enrolled. Perioperative outcomes were compared between 254 patients with preoperative anemia (hemoglobin level: males, <12 g/dL; females, <11 g/dL) and 869 patients without preoperative anemia.
  
  
  RESULTS
  Patients with preoperative anemia were significantly older and more likely to be female than patients without preoperative anemia. Patients with preoperative anemia had higher rates of diabetes mellitus, acute coronary syndrome, and history of congestive heart failure, and had lower ejection fraction and estimated glomerular filtration rate. Patients with preoperative anemia had a higher operative death rate than patients without preoperative anemia, but this difference was not statistically significant (1.6% versus 0.3%; p = 0.0501). Univariate analysis showed that postoperative low cardiac output syndrome, hemodialysis requirement, and the composite adverse outcome were significantly higher in patients with preoperative anemia than in patients without preoperative anemia. However, multivariate analysis showed that preoperative anemia was not an independent predictor of operative death, low cardiac output, hemodialysis requirement, or the composite adverse outcome.
  
  
  CONCLUSIONS
  In patients undergoing isolated off-pump CABG, preoperative anemia was not an independent predictor of postoperative adverse events.
authors.affiliation: Department of Anesthesiology, Sakakibara Heart Institute, Tokyo, Japan.
authors.forename: Sonoo
authors.initials: S
authors.lastname: Matsuda
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Fukui
authors.forename: Jun
authors.initials: J
authors.lastname: Shimizu
authors.forename: Ayako
authors.initials: A
authors.lastname: Takao
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Takanashi
authors.forename: Hitonobu
authors.initials: H
authors.lastname: Tomoike
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications / Q000401:mortality / Q000601:surgery*; D000368:Aged; D000740:Anemia / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D047549:Coronary Artery Bypass, Off-Pump / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D057234:Preoperative Period; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends