title: Incidence of and Risk Factors for Delirium After Cardiac Surgery at a Quaternary Care Center: A Retrospective Cohort Study.
abstract: OBJECTIVE
  Delirium after cardiac surgery is associated with persistent cognitive deficits and increased mortality. The authors' objective was to determine the incidence of and risk factors for delirium in a mixed cohort of patients undergoing on-pump and off-pump cardiac surgery and transcatheter aortic valve implantations (TAVI) in a Canadian quaternary care center. This study followed a pilot from the same center on patients treated in 2007.
  
  
  METHODS
  A retrospective cohort study.
  
  
  METHODS
  A quaternary care center in Vancouver, B.C., Canada.
  
  
  METHODS
  Patients undergoing cardiopulmonary bypass grafts (CABG), conventional valve replacements, combined CABG-valve replacements, transfemoral TAVI, or transapical TAVI in 2008.
  
  
  METHODS
  Data from 679 charts on demographics, medical history, medications, laboratory results, surgical procedure, and anesthesia were abstracted and analyzed using univariate and multivariate analyses. Nurses screened for delirium using the Confusion Assessment Method, and the final diagnoses were made clinically by physicians. Risk factors were identified using logistic regression and bootstrapping.
  
  
  RESULTS
  Delirium occurred in 28% of patients. Delirium was most common in transapical TAVI (47%), and least common in transfemoral TAVI (17%). Delirious patients were older and had greater preoperative cardiac and neurologic burdens than nondelirious patients. Age≥64 years, history of delirium, history of stroke/transient ischemic attack, cognitive impairment, depression, and preoperative use of beta-blocker(s) were associated independently with delirium.
  
  
  CONCLUSIONS
  The incidence of delirium varied greatly with the type of procedure. The authors' logistic regression model showed that age and certain pre-existing neurologic conditions could predict delirium after cardiac surgery.
authors.affiliation: Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, B.C. Canada.
authors.forename: Lurdes
authors.initials: L
authors.lastname: Tse
authors.affiliation: Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, B.C. Canada; Department of Anesthesia, St. Paul's Hospital, Vancouver, B.C., Canada.
authors.forename: Stephan K W
authors.initials: SK
authors.lastname: Schwarz
authors.affiliation: Department of Anesthesia, St. Paul's Hospital, Vancouver, B.C., Canada.
authors.forename: John B
authors.initials: JB
authors.lastname: Bowering
authors.affiliation: Department of Anesthesia, St. Paul's Hospital, Vancouver, B.C., Canada.
authors.forename: Randell L
authors.initials: RL
authors.lastname: Moore
authors.affiliation: Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, B.C. Canada. Electronic address: al.barr@ubc.ca.
authors.forename: Alasdair M
authors.initials: AM
authors.lastname: Barr
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001955:British Columbia / Q000453:epidemiology; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000639:trends*; D015331:Cohort Studies; D003693:Delirium / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D016304:Hospitals, Private / Q000639:trends*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
keywords: cardiac surgery; delirium; incidence; risk factor