Optimum sevoflurane concentration for I-gel insertion in unpremedicated children ★★★

• We studied sevoflurane EC50 for I-gel insertion in children.
• We found that I-gel insertion in children can be accomplished at nearly half end-tidal sevoflurane concentration (0.094%) of that required for CLMA insertion (1.9%).
• All children in both the groups did not have any major airway-related complication.

Study objectiveEnd-tidal concentration of sevoflurane for I-gel insertion in children has not been studied. This study was designed to determine the sevoflurane EC50 and EC95 for I-gel placement in children as compared with classic laryngeal mask airway (CLMA) placement.DesignThe design was a prospective, randomized controlled study.SettingsThe setting was single tertiary care center.PatientsPediatric subjects of either sex aged 1.5-8 years, weighing 10-20 kg having American Society of Anesthesiologists physical status I/II of undergoing elective cataract surgery were included in the study.InterventionInduction and maintenance of anesthesia were achieved with sevoflurane and oxygen with preservation of spontaneous breathing. Children were randomly subjected to either I-gel size 2 (group I) or CLMA size 2 (group II) insertion. The target end-tidal sevoflurane concentration (ET SEVO) was maintained for 8-10 minutes before supraglottic airway device was inserted in both the groups. In the first child, the ET SEVO was kept at 2% and was increased or decreased by 0.2% in the next child depending on the previous child's response according to Dixon method. After each supraglottic airway device insertion, child was observed for 1 minute for any “movement” or “no movement.”MeasurementsThe measurements were EC50 and EC95 for I-gel and CLMA placement in children.Main resultsEC50 and EC95 for group I were 0.94% (0.83%-1.06%) and 1.26% (1.12%-1.66%) and for group II were 1.9% (1.70%-2.1%) and 2.54% (2.24%-3.41%), respectively.ConclusionI-gel insertion in children can be accomplished at nearly half ET SEVO (0.94%) of that required for CLMA insertion (1.9%).