[Electroencephalographic monitoring during sevofluorane and halothane anesthesia in children]

Twenty-two children aged 5 to 15 years were examined. Ten children underwent fluorothane; 12 received a combination of sevofluorane and isofluorane. EEG was continuously recorded by a 9-channel computer-assisted encephalograph via bilateral electrode placement and BIS values were simultaneously measured. In the fluorothane group, EEG displayed a gradual reduction in basic rhythm, an increase in slow activity with the rhythm being recovered on emergence. The BIS index changed from 95-98 to 40-45 with a spike up to 78-84 on emergence. In the sevofluorane group, EEG recorded a pointed alpha rhythm, increased amplitude, and rhythm synchronization. The isofluorane anesthesia stage changed EEC patterns towards a reduction in cortical rhythm with slow fluctuations. The BIS value changed from 96-99 to 19-25 with 35-40 on anesthesia maintenance and up to 82-87 on emergence. The BIS data agree with EEG readings at all anesthesia stages.