[Analysis of EEG frequency in althesin anesthesia]

Twelve subjects were given Althesin until the EEG level of burst suppression was reached. The cerebral electrical activity was continuously monitored by the conventional EEG-tracing method and by a tracing compression technique (BFA), based on the time to-frequency domain conversion and the display of the spectra in prospectical array. The BFA computed in real time the power spectra of 64 frequencies (0,25-16 Hz) by means of the Fourier's transform. The depth of Althesin anesthesia proved to correlate with the EEG spectra.