title: Comparison of the effect of sevoflurane and propofol on oxygenation during gradual transition to one-lung ventilation.
abstract: BACKGROUND
  It is known that hypoxic pulmonary vasoconstriction increases as a result of intermittent regional hypoxic challenges. The aim of this study was to compare the effects of sevoflurane and propofol on oxygenation and shunt fraction during one-lung ventilation in a novel model of hypoxic preconditioning before one-lung ventilation.
  
  
  METHODS
  Sixteen Wistar-albino rats were anesthetized intra-peritoneally before venous and arterial cannulations and tracheotomized. The animals were randomly allocated to receive either sevoflurane 2% or 10mg/kg/h propofol infusion and ventilated with 100% oxygen at an inspiratory rate of 80 breaths/min for 30min. Three cycles of one-lung ventilation and two-lung ventilation were performed and one-lung ventilation was continued for 15min. Arterial blood gas samples were obtained as follows: after cannulation and tracheotomy, following 30min of treatment with sevoflurane or propofol, and at the 5th and 15th min of one-lung ventilation.
  
  
  RESULTS
  The PaO2 levels were higher and shunt fractions were lower in rats receiving propofol compared to rats treated with sevoflurane but the difference was not significant; the two groups were comparable in terms of PaCO2.
  
  
  CONCLUSIONS
  The similar effects of sevoflurane and propofol on PaO2 during one-lung ventilation following hypoxic preconditioning may be due to other causes beside the inhibition of hypoxic pulmonary vasoconstriction. Gradual transition to one-lung ventilation is a novel technique for preconditioning experiments for one-lung ventilation.
authors.affiliation: Department of Anesthesiology and Reanimation, Medical School, Dokuz Eylul University, İzmir, Turkey. Electronic address: ayse.karci@deu.edu.tr.
authors.forename: Ayşe
authors.initials: A
authors.lastname: Karci
authors.affiliation: Department of Anesthesiology and Reanimation, Medical School, Dokuz Eylul University, İzmir, Turkey.
authors.forename: Seden
authors.initials: S
authors.lastname: Duru
authors.affiliation: Department of Anesthesiology and Reanimation, Medical School, Dokuz Eylul University, İzmir, Turkey.
authors.forename: Hasan
authors.initials: H
authors.lastname: Hepağuşlar
authors.affiliation: Department of Anesthesiology, State Hospital, Denizli, Turkey.
authors.forename: Lügen
authors.initials: L
authors.lastname: Ciftçi
authors.affiliation: Department of Laboratory Animal Science, Medical School, Dokuz Eylul University, Inciralti, İzmir, Turkey.
authors.forename: Osman
authors.initials: O
authors.lastname: Yilmaz
mesh_terms: D000818:Animals; D008738:Methyl Ethers / Q000494:pharmacology*; D061810:One-Lung Ventilation; D010100:Oxygen / Q000097:blood*; D015742:Propofol / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D000077149:Sevoflurane
chemical_list: D008738:Methyl Ethers; D000077149:Sevoflurane; D010100:Oxygen; D015742:Propofol
keywords: Gradual transition; One-lung ventilation; Sevoflurane propofol