Electroencephalography monitoring at total and managed hyperthermia to 44 degrees C

: In 34 patients the abstinence syndrome was treated by hypothermia (HT) with the EEG monitoring. HT was carried out under the general propofol-fentanil anesthesia. HT was achieved in the "Hirana" bath. The temperature was increased gradually by 1 degree C per 5 minutes up to 44 degrees C. EEG was recorded before anesthesia, as well as during and after the procedure. On the initial EEG alpha- and beta-rhythms were predominant. Under the anesthesia both alpha-rhythm frequency and amplitude were enhanced, spikes and wave discharges appeared. Under HT (t = 40-42 degrees C) low voltage and wave slowing were recorded. In the range t degree--42.5-43.4 degrees C EEG registered the appearance of clinically significant "biological break point", which was followed by neuropeptide destruction. At t degree--43-44 degrees C acute suppression and, then, electrocerebral silence were observed in a majority of patients. At the end of the procedure (t = 39 degrees C) EEG returned to the initial recording.