title: Neuromuscular blocking properties of atracurium during sevoflurane or propofol anaesthesia in dogs.
abstract: OBJECTIVE
  To quantify the neuromuscular blockade (NMB) produced by atracurium in either sevoflurane or propofol-anaesthetized dogs.
  
  
  METHODS
  Twelve healthy, female adult mixed-breed dogs weighing 13 +/- 3 kg (range 10-22 kg).
  
  
  METHODS
  Three doses of atracurium (0.1, 0.2 and 0.3 mg kg(-1)) were tested at 1-week intervals. Anaesthesia was induced with inhaled sevoflurane or intravenous propofol and maintained with end-tidal sevoflurane concentrations of 1.95% (1.25 x MAC) or propofol 0.6 mg kg(-1) minute(-1) respectively. Acceleromyography and train-of-four stimulation of the fibular nerve were used for the assessment of NMB. The percentage depression of the first twitch (T1) and the fourth to the first twitch ratio (T4/T1), the maximum degree of neuromuscular block achieved and surgical muscle relaxation were recorded. Before and during neuro muscular blockade (at 10 minute intervals) body temperature, ECG, arterial blood pressure, inspired and expired CO2 concentrations and SpO2 were recorded.
  
  
  RESULTS
  Atracurium produced a dose-dependent duration of NMB in both propofol and sevoflurane-anaesthetized dogs. Duration of block was longer in dogs anaesthetized with sevoflurane. All studied doses of atracurium caused twitch depression > or =95% with little or no cardiovascular changes.
  
  
  CONCLUSIONS
  Sevoflurane produces a clinically relevant potentiation of atracurium-induced NMB in dogs compared with propofol.
  
  
  CONCLUSIONS
  Significant differences in the potentiation of NMB drugs are encountered with commonly used anaesthetics in the dog.
authors: Veterinary School, Fluminense Federal University, Rio de Janeiro, Brazil.
authors: Marcelo R
authors: MR
authors: Kastrup
authors: Firmino F
authors: FF
authors: Marsico
authors: Fabio O
authors: FO
authors: Ascoli
authors: Thomas
authors: T
authors: Becker
authors: João H N
authors: JH
authors: Soares
authors: Ignacio A
authors: IA
authors: Gomez de Segura
mesh_terms: D000768:Anesthesia, General / Q000662:veterinary*; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000494:pharmacology; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D001279:Atracurium / Q000008:administration & dosage / Q000494:pharmacology*; D004285:Dogs / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D007262:Infusions, Intravenous / Q000662:veterinary; D008738:Methyl Ethers / Q000008:administration & dosage / Q000494:pharmacology; D018482:Muscle, Skeletal / Q000187:drug effects*; D009213:Myography / Q000662:veterinary; D019148:Neuromuscular Blockade / Q000662:veterinary; D003473:Neuromuscular Nondepolarizing Agents / Q000008:administration & dosage / Q000494:pharmacology*; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology; D000077149:Sevoflurane; D016896:Treatment Outcome
chemical_list: D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D003473:Neuromuscular Nondepolarizing Agents; D001279:Atracurium; D000077149:Sevoflurane; D015742:Propofol