title: Differential effects of intravenous anaesthetic agents on the response of rat mesenteric microcirculation in vivo after haemorrhage.
abstract: BACKGROUND
  The differential effects of i.v. anaesthesia on the response of the mesenteric microcirculation after haemorrhage in vivo are previously unexplored.
  
  
  METHODS
  Male Wistar rats (n=56) were anaesthetized intravenously either with propofol and fentanyl (propofol/fentanyl), ketamine or thiopental. A tracheostomy and carotid cannulation were performed and the mesentery surgically prepared for observation of the microcirculation using fluorescent in vivo microscopy. Animals were allocated to one of three groups: control, haemorrhage or haemorrhage re-infusion.
  
  
  RESULTS
  After haemorrhage, the response of the microcirculation differed during propofol/fentanyl, ketamine and thiopental anaesthesia. During propofol/fentanyl anaesthesia there was constriction of arterioles (-16.7 (3.9)%), venules (-5.9 (1.7)) and capillaries (-16.3 (2.8)) (n=12). During ketamine and thiopental anaesthesia both constriction and dilation was observed. After haemorrhage and re-infusion, macromolecular leak occurred from venules during propofol/fentanyl and thiopental anaesthesia (P<0.05), but not during ketamine anaesthesia.
  
  
  CONCLUSIONS
  In summary, i.v. anaesthetic agents differentially alter the response of the mesenteric microcirculation to haemorrhage.
authors.affiliation: Division of Clinical Sciences, University of Sheffield, Royal Hallamshire Hospital, UK.
authors.forename: Z L S
authors.initials: ZL
authors.lastname: Brookes
authors.forename: N J
authors.initials: NJ
authors.lastname: Brown
authors.forename: C S
authors.initials: CS
authors.lastname: Reilly
mesh_terms: D019162:Anesthetics, Combined / Q000494:pharmacology; D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D000818:Animals; D005283:Fentanyl / Q000494:pharmacology; D006439:Hemodynamics / Q000187:drug effects; D006470:Hemorrhage / Q000503:physiopathology*; D007649:Ketamine / Q000494:pharmacology; D008297:Male; D008833:Microcirculation / Q000187:drug effects; D008856:Microscopy, Fluorescence; D015742:Propofol / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013152:Splanchnic Circulation / Q000187:drug effects*; D013874:Thiopental / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
chemical_list: D019162:Anesthetics, Combined; D018686:Anesthetics, Intravenous; D007649:Ketamine; D013874:Thiopental; D005283:Fentanyl; D015742:Propofol