Sevoflurane concentration for cannulation in developmental disabilities

Objective: The goal of this study was to compare the end-tidal sevoflurane concentration and time for intravenous cannulation at induction of anesthesia using sevoflurane with or without nitrous oxide in healthy children and in those with developmental disabilities. Methods: Normal and developmentally disabled children were anesthetized by inhalation of sevoflurane with nitrous oxide or with nitrous oxide-free oxygen, and intravenous cannulae were introduced. The following parameters were recorded for each patient: age, sex, height, weight, BMI, duration of intravenous cannulation, intertidal concentration of sevoflurane at the completion of intravenous cannulation, and use of nitrous oxide. Two-way ANOVA was used for statistical evaluation of the experimental data. All values were expressed as mean ± standard deviation (SD) or number (n). p-values below 0.001 were considered statistically significant (two-way ANOVA). Results: In healthy children, the end-tidal sevoflurane concentrations at the completion of the intravenous cannulation showed a significant difference between when nitrous oxide was used (4.1 ± 0.8 %) and when nitrous oxide was not used (5.1 ± 1.1 %) (p<0.001). Also, in children with developmental disabilities, the end-tidal sevoflurane concentrations at intravenous cannulation showed a significant difference between when nitrous oxide was used (4.2 ± 0.9 %) and when nitrous oxide was not used (4.9 ± 1.3 %) (p<0.001). However, there was no significant difference in the time required for intravenous cannulation from the start of anesthesia induction in either group. Conclusions：Between the healthy children and the children with developmental disabilities, no significant differences in the end-tidal sevoflurane concentrations at the completion of the intravenous cannulation and the time for the intravenous cannulation from the beginning of anesthetic induction.