Clinical implementation of advanced control in anaesthesia

A multi-sensor fusion system for monitoring and control of depth of anaesthesia in the operating theatre is described. Two types of anaesthesia measures are considered, the first being based on auditory evoked responses, while the second measure is based on cardiovascular system signals. The first measure is based on analysis of the signal using wavelets and a neuro-fuzzy system, while the second measure is based on analysis of the measurements using a rule-based fuzzy logic system. The two measures are combined to give a final level of depth of anaesthesia using another rule-based fuzzy logic system. The depth of anaesthesia level is fed back to a target controlled infusion system (TCI) to control the infusion of the drug propofol for maintaining a constant level of depth of anaesthesia.