title: Retrospective evaluation of the effect of carotid artery stenosis on cerebral oxygen saturation during off-pump coronary artery bypasses grafting in adult patients.
abstract: BACKGROUND
  It is unknown whether cerebral oxygenation in patients with carotid artery stenosis (CAS) undergoing off-pump coronary artery bypass grafting (CABG) differs from that in patients without CAS. Thus, the effect of the presence of CAS ≥ 50 % on cerebral oxygenation during off-pump CABG in adult patients was evaluated retrospectively.
  
  
  METHODS
  Eleven patients with CAS ≥ 50% and 14 patients without CAS ≥ 50% were enrolled. Regional cerebral tissue oxygen saturation (rSO2) was quantified using near-infrared spectroscopy. Mean arterial pressure, cardiac index, central venous pressure (CVP), and rSO2 at specific points were collected, and significant changes in each parameter were detected using repeated analysis of variance. Mean rSO2 and minimum rSO2 during anastomosis were analyzed by one-way analysis of variance. Multiple logistic regression analysis was used to estimate the odds ratio (OR) with 95% confidence interval (CI) for cerebral desaturation (a decrease in rSO2 ≥ 10% from preoperative value).
  
  
  RESULTS
  Two patients with CAS ≥ 50% who received complete carotid artery stenting preoperatively were excluded from the analyses. In both patients with and without CAS, a decrease in rSO2 and cardiac index and an increase in CVP were observed during anastomosis. Mean (SD) maximum decrease in rSO2 from preoperative value was 9.2 (12.7) % on the left side and 8.1 (11.7) % on the right side in patients with CAS ≥ 50%, and 13.5 (11.3) % on the left side and 16.1 (9.8) % on the right side in patients without CAS ≥ 50% (p = 0.316). Neurological complications were not identified in both patients with and without CAS ≥ 50%. In multiple logistic regression analysis, CAS ≥ 50% was not associated with an increased risk of cerebral desaturation (OR 0.160, 95% CI 0.036-0.707, p = 0.016), and rSO2 decreased with decreasing cardiac index < 2.0 l/min/m(2) (OR 3.287, 95 % CI 2.218-5.076, p < 0.001).
  
  
  CONCLUSIONS
  CAS ≥ 50% was not an independent risk factor of cerebral desaturation during off-pump CABG. Our results suggest that maintaining cardiac output can prevent a decrease in cerebral oxygenation in both patients with and without CAS ≥ 50%.
authors.affiliation: Department of Anesthesiology, Medical Hospital of Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-Ku, Tokyo, 113-8519, Japan. s-toyama@suite.plala.or.jp.
authors.forename: S
authors.initials: S
authors.lastname: Toyama
authors.affiliation: Department of Anesthesiology, Teikyo University Chiba Medical Center, 3426-3 Anesaki, Ichihara-City, Chiba, 299-0111, Japan. inchonmu@yahoo.co.jp.
authors.forename: K
authors.initials: K
authors.lastname: Matsuoka
authors.affiliation: Department of Anesthesiology, Teikyo University Chiba Medical Center, 3426-3 Anesaki, Ichihara-City, Chiba, 299-0111, Japan. ytagaito@yahoo.co.jp.
authors.forename: Y
authors.initials: Y
authors.lastname: Tagaito
authors.affiliation: Department of Anesthesiology, Teikyo University Chiba Medical Center, 3426-3 Anesaki, Ichihara-City, Chiba, 299-0111, Japan. mshimoy@jikei.ac.jp.|Department of Palliative Medicine, Jikei University Graduate School of Medicine, 3-19-18 Nishi-shimbashi, Minato-Ku, Tokyo, 105-8471, Japan. mshimoy@jikei.ac.jp.
authors.forename: M
authors.initials: M
authors.lastname: Shimoyama
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000714:Anastomosis, Surgical / Q000009:adverse effects; D001921:Brain / Q000378:metabolism*; D016893:Carotid Stenosis / Q000150:complications*; D016022:Case-Control Studies; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects* / Q000379:methods; D003331:Coronary Vessels / Q000601:surgery*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D016896:Treatment Outcome