title: Sevoflurane and desflurane protect cholinergic-induced bronchoconstriction of hyperreactive airways in rabbits.
abstract: OBJECTIVE
  The potential of desflurane to alter respiratory mechanics in the presence of bronchial hyperresponsiveness (BHR) is still a subject of debate. Accordingly, we evaluated the bronchoprotective potential of desflurane compared with sevoflurane following cholinergic lung constriction in rabbits with normal and hyperreactive airways.
  
  
  METHODS
  The input impedance of the respiratory system (Zrs) was measured during midazolam-based anesthesia before and during intravenous infusions of increasing doses of methacholine (MCh). The rabbits in the control group (Group C) were then randomized to receive either sevoflurane 1 MAC followed by desflurane 1 MAC or vice versa, whereas ovalbumin-sensitized rabbits received sevoflurane followed by desflurane (Group S-SD) or vice versa (Group S-DS). Baseline Zrs measurements and the MCh provocations were repeated under the maintenance of each volatile agent. Airway resistance (Raw), tissue damping (G), and elastance data were obtained from Zrs by model fitting.
  
  
  RESULTS
  Similar bronchoprotective effects of sevoflurane and desflurane against MCh-induced bronchoconstriction were observed independently of the severity of the bronchospasm and the presence of BHR. With sevoflurane, the decreases in Raw ranged from 22 (8.8)% to 44 (12)%, and with desflurane, they ranged from 22 (8.7)% to 50 (12)%. The increases in G reflecting the enhanced ventilation heterogeneities in the lung periphery were not affected by the volatile agents.
  
  
  CONCLUSIONS
  If the contractile stimulus is cholinergic in origin, sevoflurane and desflurane exert similar bronchoprotective potentials to act against lung constriction independent of the presence of BHR. These volatile anesthetics otherwise lack a potential to improve the enhanced ventilation heterogeneities that develop particularly in the presence of BHR.
authors: Anesthesiological Investigation Unit, University of Geneva, Switzerland.
authors: Carole F
authors: CF
authors: Myers
authors: Fabienne
authors: F
authors: Fontao
authors: Tibor Z
authors: TZ
authors: Jánosi
authors: Krisztina
authors: K
authors: Boda
authors: Ferenc
authors: F
authors: Peták
authors: Walid
authors: W
authors: Habre
mesh_terms: D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D016535:Bronchial Hyperreactivity / Q000503:physiopathology*; D016084:Bronchoconstriction / Q000187:drug effects*; D000077335:Desflurane; D007530:Isoflurane / Q000031:analogs & derivatives* / Q000494:pharmacology; D016210:Methacholine Chloride / Q000494:pharmacology*; D008738:Methyl Ethers / Q000494:pharmacology*; D018721:Muscarinic Agonists / Q000494:pharmacology*; D011817:Rabbits; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D018721:Muscarinic Agonists; D016210:Methacholine Chloride; D000077149:Sevoflurane; D000077335:Desflurane; D007530:Isoflurane