Intraoperative EEG monitoring: (I). Parametric representation of processed EEG during anesthesia.
One of the most common techniques of EEG monitoring during operations is to produce a three dimensional image by displaying the frequency distributions with respect to time as in compressed spectral array (CSA) and density-modulated spectral array (DSA). In order to characterize these images by numerical parameters, we defined two parameters; the percent spectral edge frequency as the frequency at which the one-sided-power sum reaches the designated percentage of the total; and the mean frequency as the power-weighted mean within the interval that includes a dominant spectrum in the frequency distribution. These parameters were superimposed on displays to characterize EEG changes, and they proved to be a very powerful tool to quantitate variations in data among anesthetic techniques and thus efficiently control the depth and duration of anesthesia. We report a number of actual cases.
Kinefuchi
Y
Y
Department of Anesthesiology, School of Medicine, Tokai University, Kanagawa, Japan.
Katoh
H
H
Ohtani
I
I
Iga
T
T
Shirakura
K
K
Yamasaki
Y
Y
D000328:Adult; D000758:Anesthesia; D002047:Buprenorphine; D004569:Electroencephalography / Q000295:instrumentation; D004737:Enflurane; D005283:Fentanyl; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007432:Intraoperative Period; D007649:Ketamine; D008875:Middle Aged; D009020:Morphine; D013514:Surgical Procedures, Operative
D002047:Buprenorphine; D007649:Ketamine; D009020:Morphine; D004737:Enflurane; D005283:Fentanyl