Patent ID: 7089927

Claim:
A method for monitoring anesthetization of a patient undergoing a medical procedure, comprising the steps of: (a) removably connecting a plurality of electroencephalograph (“EEG”) electrodes to a scalp of the patient; (b) administering sufficient anesthesia to the patient so that the patient attains a plane of anesthesia selected by an operator; (c) amplifying and digitizing brain waves of the patient after step (b) and before beginning the medical procedure to obtain a first set of digital data; (d) amplifying and digitizing brain waves of the patient during the medical procedure to provide a second set of digital data; (e) analyzing the first and second sets of digital data in at least one of a time domain and a frequency domain; (f) computing from the data analysis of step (e) separate trajectories for at least two different indices of an anesthetic state of the patient during the medical procedure, the indices being selected from a group including a Depth Index (DI), a Memory Index (MI) and a Pain Index (PI), wherein the DI corresponds to a depth of anesthesia of the patient, PI corresponds to a sensitivity of the patient to pain and MI corresponds to an ability of the patient to form and store memories; (g) providing a control signal when any of the trajectories indicates that the patient is deviating from the selected plane of anesthesia; and (h) automatically, in response to the control signal, adjusting an amount of an anesthetic agent administered to the patient to restore the patient to the selected plane of anesthesia, wherein a plurality of anesthetic agents are administered to the patient with each of the anesthetic agents begin directed primarily toward regulating a corresponding one of indices, with the amount of each being controlled as a function of the trajectory corresponding to that index.