title: Cerebral oxygen desaturation predicts cognitive decline and longer hospital stay after cardiac surgery.
abstract: BACKGROUND
  Previous studies have reported an 11% to 75% incidence of postoperative cognitive decline among cardiac surgery patients. The INVOS Cerebral Oximeter (Somanetics Corp, Troy, MI) is a Food and Drug Administration approved device that measures regional cerebral oxygen (rSo(2)) saturation. The purpose of this study is to examine whether decreased rSo(2) predicts cognitive decline and prolonged hospital stay after coronary artery bypass grafting (CABG).
  
  
  METHODS
  The rSo(2) was monitored intraoperatively in a cohort of primary CABG patients. Patients were prospectively randomized to a blinded control group or an unblinded intervention group. Cognitive function was assessed preoperatively, postoperatively, and at 3 months using a battery of standardized neurocognitive tests. Cognitive decline was defined as a decrease of one standard deviation or more in performance on at least one neurocognitive measure. The rSo(2) desaturation score was calculated by multiplying rSo(2) below 50% by time (seconds). Multivariate logistic regression models were used to assess cognitive decline and hospital stay. The change in cognitive performance was also assessed using a multivariate linear regression model.
  
  
  RESULTS
  Patients with rSo(2) desaturation score greater than 3,000%-second had a significantly higher risk of early postoperative cognitive decline [p = 0.024]. Patients with rSo(2) desaturation score greater than 3,000%-second also had a near threefold increased risk of prolonged hospital stay (>6 days) [p = 0.007].
  
  
  CONCLUSIONS
  Intraoperative cerebral oxygen desaturation is significantly associated with an increased risk of cognitive decline and prolonged hospital stay after CABG.
authors.affiliation: Department of Cardiac Surgery, Morristown Memorial and Gagnon Heart Hospital, Atlantic Health, Morristown, New Jersey, USA. james.slater@atlantichealth.org
authors.forename: James P
authors.initials: JP
authors.lastname: Slater
authors.forename: Theresa
authors.initials: T
authors.lastname: Guarino
authors.forename: Jessica
authors.initials: J
authors.lastname: Stack
authors.forename: Kateki
authors.initials: K
authors.lastname: Vinod
authors.forename: Rami T
authors.initials: RT
authors.lastname: Bustami
authors.forename: John M
authors.initials: JM
authors.lastname: Brown
authors.forename: Alejandro L
authors.initials: AL
authors.lastname: Rodriguez
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Magovern
authors.forename: Thomas
authors.initials: T
authors.lastname: Zaubler
authors.forename: Kenneth
authors.initials: K
authors.lastname: Freundlich
authors.forename: Grant V S
authors.initials: GV
authors.lastname: Parr
mesh_terms: D000368:Aged; D002560:Cerebrovascular Circulation / Q000502:physiology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000379:methods; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002534:Hypoxia, Brain / Q000175:diagnosis* / Q000517:prevention & control; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D015999:Multivariate Analysis; D009483:Neuropsychological Tests; D010092:Oximetry; D010101:Oxygen Consumption / Q000502:physiology; D011183:Postoperative Complications / Q000175:diagnosis; D011237:Predictive Value of Tests; D011300:Preoperative Care / Q000379:methods; D011336:Probability; D011446:Prospective Studies; D012016:Reference Values; D012307:Risk Factors; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D016896:Treatment Outcome