BACKGROUND: Although sevoflurane and desflurane exert bronchoactive effects, their impact on the airway and respiratory tissue mechanics have not been systematically compared in children, especially in those with airway susceptibility (AS). The aim of this study was to assess airway and respiratory tissue mechanics in children with and without AS during sevoflurane and desflurane anesthesia. METHODS: Respiratory system impedance was measured in healthy control children (group C, n = 20) and in those with AS (group AS, n = 20). Respiratory system impedance was determined during propofol anesthesia and during inhalation of sevoflurane and desflurane 1 minimum alveolar concentration in random order. Airway resistance, tissue damping, and elastance were determined from the respiratory system impedance spectra by model fitting. RESULTS: Children in group AS exhibited significantly higher respiratory impedance parameters compared with those in group C. Sevoflurane slightly decreased airway resistance (-7.0 +/- 1.5% vs. -4.8 +/- 2.4% in groups C and AS, respectively) in both groups. In contrast, desflurane caused elevations in airway resistance and tissue mechanical parameters, with markedly enhanced airway narrowing in children with AS (18.2 +/- 2.8% vs. 53.9 +/- 5%; P < 0.001 for airway resistance in groups C and AS, respectively). Neither the order of drug administration nor the time after the establishment of their steady state concentrations affected these findings. CONCLUSIONS: These results emphasized the deleterious effects of desflurane on the airways, particularly in children with susceptible airways in contrast with the consistent beneficial effects of sevoflurane, questioning the use of desflurane in children with AS.
BACKGROUND: Although sevoflurane and desflurane exert bronchoactive effects, their impact on the airway and respiratory tissue mechanics have not been systematically compared in children, especially in those with airway susceptibility (AS). The aim of this study was to assess airway and respiratory tissue mechanics in children with and without AS during sevoflurane and desflurane anesthesia. METHODS: Respiratory system impedance was measured in healthy control children (group C, n = 20) and in those with AS (group AS, n = 20). Respiratory system impedance was determined during propofol anesthesia and during inhalation of sevoflurane and desflurane 1 minimum alveolar concentration in random order. Airway resistance, tissue damping, and elastance were determined from the respiratory system impedance spectra by model fitting. RESULTS:Children in group AS exhibited significantly higher respiratory impedance parameters compared with those in group C. Sevoflurane slightly decreased airway resistance (-7.0 +/- 1.5% vs. -4.8 +/- 2.4% in groups C and AS, respectively) in both groups. In contrast, desflurane caused elevations in airway resistance and tissue mechanical parameters, with markedly enhanced airway narrowing in children with AS (18.2 +/- 2.8% vs. 53.9 +/- 5%; P < 0.001 for airway resistance in groups C and AS, respectively). Neither the order of drug administration nor the time after the establishment of their steady state concentrations affected these findings. CONCLUSIONS: These results emphasized the deleterious effects of desflurane on the airways, particularly in children with susceptible airways in contrast with the consistent beneficial effects of sevoflurane, questioning the use of desflurane in children with AS.