title: Preoperative regional cerebral oxygen saturation is a predictor of postoperative delirium in on-pump cardiac surgery patients: a prospective observational trial.
abstract: BACKGROUND
  Postoperative delirium is an important problem in patients undergoing major surgery. Cerebral oximetry is a non-invasive method to detect imbalances in the cerebral oxygen supply/demand-ratio. Low preoperative cerebral oxygen saturation (ScO₂) levels have been associated with postoperative delirium in non-cardiac surgery patients. The present prospective observational study determines the relationship between pre- and intra-operative ScO₂ levels and postoperative delirium in patients undergoing on-pump cardiac surgery.
  
  
  METHODS
  After approval of the local ethical committee and written informed consent, N = 231 patients scheduled for elective/urgent cardiac surgery were enrolled. Delirium was assessed by the confusion-assessment-method for the intensive care unit (CAM-ICU) on the first three days after surgery. ScO₂ was obtained on the day before surgery, immediately before surgery and throughout the surgical procedure. Preoperative cognitive function, demographic, surgery related, and intra- and post-operative physiological data were registered.
  
  
  RESULTS
  Patients with delirium had lower pre- and intra-operative ScO₂ readings, were older, had lower mini-mental-status-examination(MMSE) scores, higher additive EuroScore and lower preoperative haemoglobin-levels. The binary logistic regression identified older age, lower MMSE, neurological or psychiatric disease and lower preoperative ScO₂ as independent predictors of postoperative delirium.
  
  
  CONCLUSIONS
  The presented study shows that a low preoperative ScO₂ is associated with postoperative delirium after on-pump cardiac surgery.
authors.affiliation: Department of Anaesthesiology, University of Luebeck, Ratzeburger Allee 160, Luebeck, 23538, Germany.
authors.forename: Julika
authors.initials: J
authors.lastname: Schoen
authors.forename: Joscha
authors.initials: J
authors.lastname: Meyerrose
authors.forename: Hauke
authors.initials: H
authors.lastname: Paarmann
authors.forename: Matthias
authors.initials: M
authors.lastname: Heringlake
authors.forename: Michael
authors.initials: M
authors.lastname: Hueppe
authors.forename: Klaus-Ulrich
authors.initials: KU
authors.lastname: Berger
mesh_terms: D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D054022:Cerebrum / Q000378:metabolism*; D003693:Delirium / Q000209:etiology*; D005260:Female; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D008875:Middle Aged; D010092:Oximetry; D010100:Oxygen / Q000378:metabolism*; D011237:Predictive Value of Tests; D011446:Prospective Studies
chemical_list: D010100:Oxygen