A microprocessor based instrument for the spectral analysis of the EEG in anaesthesia.

An instrument for monitoring the frequency components contained in the electroencephalogram is described. The technique uses the fast Fourier transform which is implemented in a microprocessor controlled 'black box'. The control and display of the data are organised by a conventional microcomputer. The system is designed for use by practising anaesthetists in a district general hospital environment and is, therefore, inexpensive and simple to operate. The operation of the equipment is described and some limited results from early clinical trials are presented.