title: Postoperative delirium and short-term cognitive dysfunction occur more frequently in patients undergoing valve surgery with or without coronary artery bypass graft surgery compared with coronary artery bypass graft surgery alone: results of a pilot study.
abstract: OBJECTIVE
  The authors tested the hypothesis that patients undergoing valve repair or replacement surgery with or without coronary artery bypass graft (CABG) surgery using cardiopulmonary bypass (CPB) had a greater incidence of postoperative delirium and cognitive dysfunction compared with patients undergoing CABG surgery alone.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Veterans Affairs medical center.
  
  
  METHODS
  Forty-four age- and education-balanced male patients (≥ 55 years of age) undergoing elective cardiac surgery with CPB (n = 22 valve ± CABG surgery and n = 22 CABG surgery alone) and nonsurgical controls (n = 22) were recruited.
  
  
  METHODS
  None.
  
  
  RESULTS
  Delirium was assessed with the Intensive Care Delirium Screening Checklist before and for 5 consecutive days after surgery. Recent verbal and nonverbal memory and executive functions were assessed using a psychometric test battery before and 1 week after cardiac surgery or at 1-week intervals in nonsurgical controls. Intensive care unit stay, hospital stay, and 30-day readmission were significantly (p = 0.03, p = 0.01, and p = 0.04, respectively) longer in patients undergoing valve surgery ± CABG surgery versus CABG surgery alone. Postoperative delirium occurred more frequently (p = 0.01) in patients undergoing valve ± CABG surgery versus CABG surgery alone. Overall cognitive performance (composite z score) after surgery also was impaired significantly (p = 0.004) in patients undergoing valve ± CABG surgery compared with CABG surgery alone. The composite z score after surgery decreased by at least 1.5 standard deviations in 11 patients (50%) versus 1 patient (5%) without valve surgery compared with nonsurgical controls (p = 0.001, Fisher's exact test). The presence of delirium predicted a composite z score decrease of 1.2 points (odds ratio = 0.30; 95% confidence interval, 0.13-0.68).
  
  
  CONCLUSIONS
  The results indicated that patients undergoing valve surgery with or without CABG surgery have a higher incidence of postoperative delirium and cognitive dysfunction 1 week after surgery compared with those undergoing CABG surgery alone.
authors.affiliation: Department of Anesthesiology, Medical College of Wisconsin and Clement J Zablocki Veterans Administration Medical Center, Milwaukee, WI 53295, USA. judith.hudetz@va.gov
authors.forename: Judith A
authors.initials: JA
authors.lastname: Hudetz
authors.forename: Zafar
authors.initials: Z
authors.lastname: Iqbal
authors.forename: Sweeta D
authors.initials: SD
authors.lastname: Gandhi
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Patterson
authors.forename: Alison J
authors.initials: AJ
authors.lastname: Byrne
authors.forename: Paul S
authors.initials: PS
authors.lastname: Pagel
mesh_terms: D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D057189:Checklist; D003072:Cognition Disorders / Q000453:epidemiology* / Q000209:etiology / Q000523:psychology; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003693:Delirium / Q000453:epidemiology* / Q000209:etiology; D003863:Depression / Q000209:etiology / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D056344:Executive Function / Q000187:drug effects; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects; D006351:Heart Valves / Q000601:surgery*; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects; D008875:Middle Aged; D009483:Neuropsychological Tests; D010865:Pilot Projects; D011183:Postoperative Complications / Q000453:epidemiology* / Q000523:psychology; D011569:Psychiatric Status Rating Scales