title: Propofol is associated with impaired brain metabolism during hypothermic circulatory arrest: an experimental microdialysis study.
abstract: BACKGROUND
  Propofol is a widely used anesthetic in cardiac surgery. It has been shown to increase cerebrovascular resistance resulting in decreased cerebral blood flow. Efficient brain perfusion and tissue oxygenation during cardiopulmonary bypass (CPB) is essential in surgery requiring hypothermic circulatory arrest (HCA). The effects of propofol on brain metabolism are reported in a surviving porcine model of HCA.
  
  
  METHODS
  Twenty female juvenile pigs undergoing 75 minutes of HCA at a brain temperature of 18 degrees C were assigned to either propofol- or isoflurane anesthesia combined with alpha-stat perfusion strategy during CPB cooling and rewarming. Brain microdialysis analysis was used for determination of brain metabolism, and tissue oxygen partial pressure and intracranial pressures were also followed-up until 8 hours postoperatively.
  
  
  RESULTS
  Brain concentrations of glutamate and glycerol were significantly higher in the propofol group throughout the experiment (P < .01 and P < .01, respectively). The lactate/pyruvate ratio was significantly higher in the propofol group at 6-, 7-, and 8-hour intervals (P < .05, P < .01, and P < .05, respectively). The intracranial pressure was significantly higher at the 8-hour postoperative interval (P < .05) in the propofol group. A trend toward higher brain oxygen concentrations was observed in the isoflurane group.
  
  
  CONCLUSIONS
  Anesthesia with propofol as compared with isoflurane is associated with impaired brain metabolism during experimental HCA.
authors.affiliation: Department of Surgery, Clinical Research Center, Oulu University Hospital, University of Oulu, Oulu, Finland. sdahlbac@paju.oulu.fi
authors.forename: Sebastian
authors.initials: S
authors.lastname: Dahlbacka
authors.forename: Jussi
authors.initials: J
authors.lastname: Mäkelä
authors.forename: Timo
authors.initials: T
authors.lastname: Kaakinen
authors.forename: Hanna
authors.initials: H
authors.lastname: Alaoja
authors.forename: Janne
authors.initials: J
authors.lastname: Heikkinen
authors.forename: Päivi
authors.initials: P
authors.lastname: Laurila
authors.forename: Kai
authors.initials: K
authors.lastname: Kiviluoma
authors.forename: Timo
authors.initials: T
authors.lastname: Salomäki
authors.forename: Hannu
authors.initials: H
authors.lastname: Tuominen
authors.forename: Pasi
authors.initials: P
authors.lastname: Ohtonen
authors.forename: Pasi
authors.initials: P
authors.lastname: Lepola
authors.forename: Fausto
authors.initials: F
authors.lastname: Biancari
authors.forename: Tatu
authors.initials: T
authors.lastname: Juvonen
mesh_terms: D018686:Anesthetics, Intravenous / Q000009:adverse effects; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism*; D001928:Brain Diseases, Metabolic / Q000139:chemically induced* / Q000175:diagnosis / Q000378:metabolism*; D050792:Circulatory Arrest, Deep Hypothermia Induced; D005260:Female; D017551:Microdialysis; D015742:Propofol / Q000009:adverse effects*; D013552:Swine
chemical_list: D018686:Anesthetics, Intravenous; D015742:Propofol