The Comparison of Measured Hypnotic Levels among Propofol, Sevoflurane and Desflurane Anesthesia by Using EEG-entropy and Bispectral Index

Joo, Jin Deok; Choi, Jin Whan; In, Jang Hjeok; Choi, Jin Woo; Lee, Hae Jin; Jung, Hong Soo; Kim, Dae Woo

Abstract

BACKGROUND: Sevoflurane has been reported to associate with epileptiform activity during a rapidly increasing concentration, but desflurane isn't associated. This study was designed to compare the measured hypnotic levels by using EEG-entropy and bispectral index (BIS) among propofol target-controlled infusion (TCI), sevoflurane and desflurane anesthesia.
METHODS
Sixty-five patients undergoing total hysterectomy were studied. Thirty patients were anesthetized with propofol TCI, twenty patients with sevoflurane, and fifteen patients with desflurane anesthesia. BIS, response entropy (RE), state entropy (SE), and hemodynamic variables were collected on the effect site concentrations of 1.5-10.0micro/ml for propofol TCI group. On the other hand, those data were collected on the end-tidal concentrations of 1.0-6.0 vol% for sevoflurane group and, 1.0-13.0 vol% for desflurane group.
RESULTS
In propofol TCI group, there was a strong correlation between the measured hypnotic levels and the effect site concentrations of 1.5-10.0micro/ml. Furthermore, the measured values were significantly lower than previous corresponding values on 3.0-4.0 and 8.0micro/ml of the effect site concentrations. In sevoflurane group, the measured hypnotic levels increased paradoxically on the end-tidal concentration of 2.0-5.0 vol%. In desflurane group, the measured hypnotic levels showed ceiling effect in the concentration ranges of 3.0-12.0 vol%.
CONCLUSIONS
The measured values by using EEG-entropy and BIS with propofol TCI were considered as useful indices of hypnotic level because of showing a strong correlation. However, those values didn't reflect real clinical hypnotic levels well partly with sevoflurane anesthesia because the measured hypnotic levels increased paradoxically. And it should be considered that those values showed ceiling effect from 3.0 vol% onward with desflurane anesthesia.