[Intraoperative computed EEG monitoring for evaluating the adequacy of general anesthesia]

The article analyses the possibilities of computed EEG monitoring for evaluation of the magnitude and adequacy of the modern methods of general anesthesia: NLA, NLA with halothane inhalation, NLA including Kalipsol bolus administration. An original coefficient, called the adequacy index (AI), was found, which reflects the percentage contribution of deep rhythms (delta and theta) to the total power of the EEG in the range of 0 to 20 Hz. It is shown that the dynamics of this index correlates with the degree of the blocking of entry of sensory nociceptive information into the CNS. The lower boundary of AI-70% was determined, below which the generally accepted signs of anesthesia inadequacy appear: hyperactivity develops, a shift of pH in the acid direction occurs, and the base deficiency increases. It is suggested that determination of AI is used as a highly sensitive and operative test for routine monitoring of the patient's intraoperative condition and express diagnosis of inefficacy of anesthesia.