title: Determination of the minimum anesthetic concentration of sevoflurane in thick-billed parrots (Rhynchopsitta pachyrhyncha).
abstract: OBJECTIVE
  To determine the minimum anesthetic concentration (MAC) of sevoflurane in thick-billed parrots (Rhynchopsitta pachyrhyncha) and compare MAC obtained via mechanical and electrical stimulation.
  
  
  METHODS
  15 healthy thick-billed parrots.
  
  
  METHODS
  Anesthesia was induced in each parrot by administration of sevoflurane in oxygen. An end-tidal sevoflurane concentration of 2.5% was established in the first bird. Fifteen minutes was allowed for equilibration. Then, 2 types of noxious stimulation (mechanical and electrical) were applied; stimuli were separated by 15 minutes. Responses to stimuli were graded as positive or negative. For a positive or negative response to a stimulus, the target end-tidal sevoflurane concentration of the subsequent bird was increased or decreased by 10%, respectively. The MAC was calculated as the mean end-tidal sevoflurane concentration during crossover events, defined as instances in which independent pairs of birds evaluated in succession had opposite responses. A quantal method was used to determine sevoflurane MAC. Physiologic variables and arterial blood gas values were also measured.
  
  
  RESULTS
  Via quantal analysis, mean sevoflurane MAC in thick-billed parrots determined with mechanical stimulation was 2.35% (90% fiducial interval, 1.32% to 2.66%), which differed significantly from the mean sevoflurane MAC determined with electrical stimulation, which was 4.24% (90% fiducial interval, 3.61% to 8.71%).
  
  
  CONCLUSIONS
  Sevoflurane MAC in thick-billed parrots determined by mechanical stimulation was similar to values determined in chickens and mammals. Sevoflurane MAC determined by electrical stimulation was significantly higher, which suggested that the 2 types of stimulation did not induce similar results in thick-billed parrots.
authors.affiliation: Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA. kaphair@gmail.com
authors.forename: Kristen A
authors.initials: KA
authors.lastname: Phair
authors.forename: R Scott
authors.initials: RS
authors.lastname: Larsen
authors.forename: Raymund F
authors.initials: RF
authors.lastname: Wack
authors.forename: Yael
authors.initials: Y
authors.lastname: Shilo-Benjamini
authors.forename: Bruno H
authors.initials: BH
authors.lastname: Pypendop
mesh_terms: D000769:Anesthesia, Inhalation / Q000379:methods / Q000662:veterinary*; D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D000818:Animals; D001784:Blood Gas Analysis; D001786:Blood Glucose / Q000378:metabolism; D001831:Body Temperature / Q000502:physiology; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D004573:Electrolytes / Q000097:blood; D005260:Female; D006339:Heart Rate / Q000502:physiology; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage*; D010311:Parrots / Q000502:physiology*; D012119:Respiration; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D001786:Blood Glucose; D004573:Electrolytes; D008738:Methyl Ethers; D000077149:Sevoflurane