title: The interaction of nitrous oxide and fentanyl on the minimum alveolar concentration of sevoflurane blocking motor movement (MACNM) in dogs.
abstract: The study objective was to determine the effects of 70% nitrous oxide (N2O) and fentanyl on the end-tidal concentration of sevoflurane necessary to prevent movement (MACNM) in response to noxious stimulation in dogs. Six healthy, adult, intact male, mixed-breed dogs were used on 3 occasions in a randomized crossover design. After induction of anesthesia with sevoflurane, each of the following treatments was randomly administered: fentanyl loading dose (Ld) of 15 μg/kg and infusion of 6 μg/kg per hour [treatment 1 (T1)], 70% N2O (T2), or fentanyl (Ld of 15 μg/kg and infusion of 6 μg/kg per hour) combined with 70% N2O (T3). Each dog received each of the 3 treatments once during the 3-week period. Determination of MACNM was initiated 90 min after the start of each treatment. The values were compared using the baseline MACNM, which had been determined in a previous study on the same group of dogs. Data were analyzed using a mixed-model analysis of variance (ANOVA) and Tukey-Kramer tests, and expressed as least squares mean ± SEM. The baseline MACNM decreased by 36.6 ± 4.0%, 15.0 ± 4.0%, and 46.0 ± 4.0% for T1, T2, and T3, respectively (P < 0.05), and differed (P < 0.05) among treatments. Mean fentanyl plasma concentrations did not differ (P ≥ 0.05) between T1 (3.70 ± 0.56 ng/mL) and T3 (3.50 ± 0.56 ng/mL). The combination of fentanyl and N2O resulted in a greater sevoflurane MACNM sparing effect than either treatment alone.
authors: Department of Large Animal Clinical Sciences (Seddighi, Doherty); Department of Small Animal Clinical Sciences (Egger, Henn); Department of Biomedical and Diagnostic Sciences (Rohrbach), College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA; Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA (Kukanich).
authors: Reza
authors: R
authors: Seddighi
authors: Department of Large Animal Clinical Sciences (Seddighi, Doherty); Department of Small Animal Clinical Sciences (Egger, Henn); Department of Biomedical and Diagnostic Sciences (Rohrbach), College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA; Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA (Kukanich).
authors: Thomas J
authors: TJ
authors: Doherty
authors: Department of Large Animal Clinical Sciences (Seddighi, Doherty); Department of Small Animal Clinical Sciences (Egger, Henn); Department of Biomedical and Diagnostic Sciences (Rohrbach), College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA; Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA (Kukanich).
authors: Butch
authors: B
authors: Kukanich
authors: Department of Large Animal Clinical Sciences (Seddighi, Doherty); Department of Small Animal Clinical Sciences (Egger, Henn); Department of Biomedical and Diagnostic Sciences (Rohrbach), College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA; Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA (Kukanich).
authors: Christine M
authors: CM
authors: Egger
authors: Department of Large Animal Clinical Sciences (Seddighi, Doherty); Department of Small Animal Clinical Sciences (Egger, Henn); Department of Biomedical and Diagnostic Sciences (Rohrbach), College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA; Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA (Kukanich).
authors: Melissa A
authors: MA
authors: Henn
authors: Department of Large Animal Clinical Sciences (Seddighi, Doherty); Department of Small Animal Clinical Sciences (Egger, Henn); Department of Biomedical and Diagnostic Sciences (Rohrbach), College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA; Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA (Kukanich).
authors: Whitney M
authors: WM
authors: Long
authors: Department of Large Animal Clinical Sciences (Seddighi, Doherty); Department of Small Animal Clinical Sciences (Egger, Henn); Department of Biomedical and Diagnostic Sciences (Rohrbach), College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA; Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA (Kukanich).
authors: Barton W
authors: BW
authors: Rohrbach
mesh_terms: D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology; D000818:Animals; D018592:Cross-Over Studies; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D005283:Fentanyl / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000494:pharmacology*; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D009609:Nitrous Oxide / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000494:pharmacology*; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D000077149:Sevoflurane; D009609:Nitrous Oxide; D005283:Fentanyl