Fuzzy control of blood pressure during anesthesia with isoflurane

A fuzzy controller which controls the depth of anesthesia during surgery with isoflurane was designed and implemented on a personal computer. The mean arterial pressure (MAP) was taken as a measure for the depth of anesthesia. The design process was iterative and the reference points of the membership functions as well as the linguistic rules were determined by trial and error. The control rules made use of the error between the desired and the actual values of MAP as well as the integral of the error. The controller was tested in several surgical operations, and it was observed that the anesthetists supervising the controller never had to intervene or override it