title: Impact of chronic obstructive pulmonary disease severity on surgical outcomes in patients undergoing non-emergent coronary artery bypass grafting.
abstract: OBJECTIVE
  Although the association between chronic obstructive pulmonary disease (COPD) and adverse surgical outcomes has been previously demonstrated, the impact of COPD severity on postoperative mortality and morbidity remains unclear. Our objective was to analyse the prognostic implication of COPD stages as defined by the Global Initiative for Chronic Obstructive Lung Disease.
  
  
  METHODS
  Between September 1997 and April 2010, 13,638 patients undergoing first time isolated CABG were retrospectively reviewed, of whom 2421 patients were excluded due to lack of spirometry records or restrictive pattern on spirometry. The remaining 11,217 patients were divided into three groups: group 1 (including patients with normal spirometry and patients with mild COPD (FEV1/FVC ratio<70%, FEV1≥80% predicted), group 2 (moderate COPD: FEV1/FVC ratio<70%, 50%≤FEV1<80% predicted) and group 3 (severe COPD: FEV1/FVC ratio<70%, FEV1<50% predicted). Logistic regression was used to examine the effect of COPD severity on early mortality and morbidity, after adjusting for differences in patient characteristics.
  
  
  RESULTS
  Early mortality in the three groups was 1.4, 2.9 and 5.7% respectively (P<0.001). Similarly, a consistent trend of increasing frequency of postoperative complications with advanced COPD stage was noted. On multivariate analysis, severe COPD was found to be significantly associated with early mortality [adjusted OR, 2.31 (95% CI) (1.23-4.36)], P=0.01.
  
  
  CONCLUSIONS
  The severity of COPD as defined by spirometry can be a prognostic marker in patients undergoing CABG. Spirometric criteria may help refining currently used operative risk scores.
authors.affiliation: Department of Cardiothoracic Surgery, Liverpool Heart and Chest Hospital, Liverpool, UK. hzayed@hotmail.com
authors.forename: Hesham Z
authors.initials: HZ
authors.lastname: Saleh
authors.forename: Kamlesh
authors.initials: K
authors.lastname: Mohan
authors.forename: Matthew
authors.initials: M
authors.lastname: Shaw
authors.forename: Omar
authors.initials: O
authors.lastname: Al-Rawi
authors.forename: Hany
authors.initials: H
authors.lastname: Elsayed
authors.forename: Martin
authors.initials: M
authors.lastname: Walshaw
authors.forename: John A C
authors.initials: JA
authors.lastname: Chalmers
authors.forename: Brian M
authors.initials: BM
authors.lastname: Fabri
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass / Q000401:mortality; D003324:Coronary Artery Disease / Q000150:complications / Q000401:mortality / Q000601:surgery*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000401:mortality / Q000503:physiopathology*; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D013147:Spirometry; D016896:Treatment Outcome; D014797:Vital Capacity