Correlation between bispectral index and patient state index in children under sevoflurane anesthesia

Background Because the unanticipated arousal or hemodynamic instability during anesthesia may adversely affect the physical and emotional welfare of children, adequate management of the anesthesia depth is required. We aimed to compare Bispectral Index (BIS) and Patient State Index (PSI) in children during sevoflurane anesthesia and evaluate PSI as depth of anesthesia monitor in children aged 6 months–12 years. Methods In this prospective observational study, children aged 6 months–12 years old scheduled for elective surgery under sevoflurane anesthesia were enrolled from November 2018 to June 2019. We monitored BIS and PSI at different sevoflurane concentrations. The primary outcome was the correlation between BIS and PSI. The correlation between BIS and PSI at different sevoflurane concentrations (at 1, 1.5, and 2 MACs) and at different age groups (6 months–2 years, 2–7 years, and 8–12 years) was also investigated. Results Bispectral index and PSI showed a fair correlation (r = .430; 95% confidence interval [CI], 0.297–0.546; p