Bispectral Index versus the University of Michigan Sedation Scale in assessing sedation depth during pediatric drug-induced sleep endoscopy.

Background And Purpose: Bispectral Index (BIS) and University of Michigan Sedation Scale (UMSS) were two commonly used methods of monitoring the sedation depth, but their correlation was not clear. The purpose of this study is to ascertain if BIS correlates with UMSS in determining the sedation level during pediatric drug-induced sleep endoscopy (DISE).

Methods: One-hundred children, aged 36-143 months, with ASA I~II grade, were enrolled. They were subject to general anesthesia for an elective adenotonsillectomy. Two drug regimens were used. After UMSS ≥ 3, the sites of airway obstructions were located by checking the supraglottic airway structures with a fibrous laryngoscope. UMSS scores, BIS values, electromyography (EMG), and signal quality indices (SQIs) were recorded at the pre-medication and pre-DISE baseline (T), 5 min subsequent to medication administration but prior to DISE initiation (T), 1 min after DISE was initiated (T), 1 min after DISE was completed (T), 1 min subsequent to tracheal intubation (T), 1 min following extubation (T), and 30 min past extubation (T).

Results: There were strong correlations between BIS monitor readings and UMSS scores for total and two regimens. Kappa values revealed moderate agreement between BIS and UMSS for total and two regimens. The agreement rates were 67.47% for the total, 61.43% for Regimen 1, and 73.42% for Regimen 2, respectively.

Conclusion: BIS correlates with UMSS in determining the sedation level during pediatric DISE for two regimens. BIS might serve as an appropriate indicator of sedation intensity when UMSS could not be used.