The paper describes research into a novel hierarchical architecture for fuzzy logic monitoring and control of intravenous anaesthesia with two main objectives. The primary task is to utilise auditory evoked response signals for augmenting cardiovascular and body function signs into a multisensor fuzzy model-based fusion strategy for anaesthesia monitoring and control. The secondary task is to extend an existing fuzzy patient model for use as a training simulator via computer-based models. This demonstrates a totally fuzzy-logic-based architecture for manipulating complex procedures on a complex process (i.e. hospital patients).