title: Intraoperative hypotension and delirium after on-pump cardiac surgery.
abstract: BACKGROUND
  Delirium is a common complication after cardiac surgery and may be as a result of inadequate cerebral perfusion. We studied delirium after cardiac surgery in relation to intraoperative hypotension (IOH).
  
  
  METHODS
  This observational single-centre, cohort study was nested in a randomized trial, on a single intraoperative dose of dexamethasone vs placebo during cardiac surgery. During the first four postoperative days, patients were screened for delirium based on the Confusion Assessment Method (CAM) for Intensive Care Unit on the intensive care unit, CAM on the ward, and by inspection of medical records. To combine depth and duration of IOH, we computed the area under the curve for four blood pressure thresholds. Logistic regression analyses were performed to investigate the association between IOH and the occurrence of postoperative delirium, adjusting for confounding and using a 99% confidence interval to correct for multiple testing.
  
  
  RESULTS
  Of the 734 included patients, 99 patients (13%) developed postoperative delirium. The adjusted Odds Ratio for the Mean Arterial Pressure <60 mm Hg threshold was 1.04 (99% confidence interval: 0.99-1.10) for each 1000 mm Hg(2) min(2) AUC(2) increase. IOH, as defined according to the other three definitions, was not associated with postoperative delirium either. Deep and prolonged IOH seemed to increase the risk of delirium, but this was not statistically significant.
  
  
  CONCLUSIONS
  Independent of the applied definition, IOH was not associated with the occurrence of delirium after cardiac surgery.
authors.affiliation: Department of Anesthesiology, University Medical Center Utrecht, P.O. Box 85500, Utrecht 3508 GA, the Netherlands e.m.wesselink-5@umcutrecht.nl.
authors.forename: E M
authors.initials: EM
authors.lastname: Wesselink
authors.affiliation: Department of Anesthesiology, University Medical Center Utrecht, P.O. Box 85500, Utrecht 3508 GA, the Netherlands.
authors.forename: T H
authors.initials: TH
authors.lastname: Kappen
authors.affiliation: Department of Anesthesiology, University Medical Center Utrecht, P.O. Box 85500, Utrecht 3508 GA, the Netherlands.
authors.forename: W A
authors.initials: WA
authors.lastname: van Klei
authors.affiliation: Department of Anesthesiology, University Medical Center Utrecht, P.O. Box 85500, Utrecht 3508 GA, the Netherlands.
authors.forename: J M
authors.initials: JM
authors.lastname: Dieleman
authors.affiliation: Department of Intensive Care Medicine, University Medical Center Utrecht, P.O. Box 85500, Utrecht 3508 GA, the Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: van Dijk
authors.affiliation: Department of Intensive Care Medicine, University Medical Center Utrecht, P.O. Box 85500, Utrecht 3508 GA, the Netherlands.
authors.forename: A J C
authors.initials: AJ
authors.lastname: Slooter
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult; D000932:Antiemetics / Q000008:administration & dosage; D006348:Cardiac Surgical Procedures; D015331:Cohort Studies; D003693:Delirium / Q000453:epidemiology; D003907:Dexamethasone / Q000008:administration & dosage; D007022:Hypotension / Q000453:epidemiology; D007431:Intraoperative Complications / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology; D016032:Randomized Controlled Trials as Topic
chemical_list: D000932:Antiemetics; D003907:Dexamethasone
keywords: cardiac surgical procedures; delirium dementia, amnestic cognitive disorders; hypotension