title: Pre-existing cerebral infarcts as a risk factor for delirium after coronary artery bypass graft surgery.
abstract: OBJECTIVE
  Delirium is a common and critical clinical syndrome in older patients. We examined whether abnormalities in the brain that could be assessed by magnetic resonance imaging predisposed patients to develop delirium after coronary artery bypass graft surgery. We also analysed the association between delirium and cognitive dysfunction after coronary artery bypass graft surgery.
  
  
  METHODS
  Data were collected prospectively on 153 patients aged 60 years or older who consecutively underwent elective isolated coronary artery bypass graft surgery. All patients were assessed for prior cerebral infarctions and craniocervical artery stenosis by magnetic resonance imaging (MRI) and angiography of their brains. Atherosclerosis of the ascending aorta was examined by epiaortic ultrasound at the time of surgery. Individual cognitive status was measured using four tests in all the patients before surgery and on the seventh postoperative day. A single psychiatrist diagnosed delirium using the Diagnostic and Statistical Manual of Mental Disorders 4th edition IV criteria.
  
  
  RESULTS
  Postoperative delirium occurred in 16 patients (10.5%). Compared with patients who did not develop postoperative delirium, delirious patients had significantly higher rates of peripheral artery disease, preoperative decline in global cognitive function and pre-existing multiple cerebral infarctions on MRI. In addition, 9 (56%) of the delirious patients suffered postoperative cognitive dysfunction. Stepwise logistic regression analysis found significant independent predictors of postoperative delirium to be preoperative cerebral infarcts on MRI (odds ratio [OR], 2.26; 95% confidence interval [CI] 1.10-4.78), preoperative decline in global cognitive function (OR 4.54; 95% CI 1.21-16.51) and atherosclerosis of the ascending aorta (OR 2.44; 95% CI 1.03-5.62).
  
  
  CONCLUSIONS
  Our findings suggested that postoperative delirium was associated with pre-existing multiple cerebral infarctions on MRI, preoperative decline in global cognitive function and ascending aortic atherosclerosis in elderly patients undergoing coronary artery bypass graft surgery and increased risk of postoperative cognitive dysfunction.
authors.affiliation: Department of Anesthesiology, Kumamoto Chuo Hospital, Minami-ku, Kumamoto, Japan.
authors.forename: Sumi
authors.initials: S
authors.lastname: Otomo
authors.forename: Kengo
authors.initials: K
authors.lastname: Maekawa
authors.forename: Tomoko
authors.initials: T
authors.lastname: Goto
authors.forename: Tomoko
authors.initials: T
authors.lastname: Baba
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yoshitake
mesh_terms: D001018:Aortic Diseases / Q000150:complications / Q000175:diagnosis; D050197:Atherosclerosis / Q000150:complications / Q000175:diagnosis; D002533:Cerebral Angiography; D002544:Cerebral Infarction / Q000150:complications* / Q000175:diagnosis; D003071:Cognition; D003072:Cognition Disorders / Q000150:complications / Q000175:diagnosis; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003693:Delirium / Q000175:diagnosis / Q000209:etiology* / Q000523:psychology; D017558:Elective Surgical Procedures; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011446:Prospective Studies; D012307:Risk Factors; D018084:Ultrasonography, Interventional
keywords: Cerebral infarction; Coronary artery bypass graft surgery; Magnetic resonance imaging; Postoperative delirium