Bispectral Index™ values are higher during halothane vs. sevoflurane anesthesia in children, but not in infants

BACKGROUND: Previously, we have shown in adult patients that bispectral index score (BIS) values are significantly higher during halothane anesthesia (53-61 units) as compared with those observed during equipotent concentrations of sevoflurane (39-43 units). Because halothane is frequently used in the pediatric setting, we tested the hypothesis that BIS values observed in children might also be higher during general anesthesia with halothane than with sevoflurane. METHODS: Forty-one healthy, unpremedicated pediatric patients scheduled for elective operations received either halothane or sevoflurane titrated as appropriate for surgical stimulation. RESULTS: During maintenance sevoflurane anesthesia (n=20), the mean BIS values and percent end-tidal concentrations were 44+/-14 and 2.1+/-0.6, respectively, whereas for the halothane group (n=21) the corresponding values were 61+/-7 and 1.1+/-0.4, respectively. CONCLUSION: These findings suggest that BIS values are higher during halothane vs. sevoflurane anesthesia in children, but not in infants.