Effects of concentrations of enflurane or isoflurane on EEG power spectrums.
- VernacularTitle:相同MAC浓度的安氟醚和异氟醚对脑电图功率谱的影响
- Author:
Xiao HU
;
Meijin MENG
;
Jinfan ZHANG
- Publication Type:Journal Article
- Keywords:
Median power frequency;
Spectral edge frequency;
Enflurane;
Isoflurane
- From:
Chinese Journal of Anesthesiology
1995;0(10):-
- CountryChina
- Language:Chinese
-
Abstract:
The purpose of this study was prospectively to research the relationship between EEG power spectrum and anesthesia depth. Twenty-four patients,aged 20 to 50 years , ASA grade ,scheduled for selected surgical operations, were randomly divided into two groups:enflurane and isoflurane groups. Anesthesia was induced by thiopental 5 mg/kg and atracurium 6-7 mg/kg intravenously and maintained by inhalation anesthetics. After intubation patients were ventilated mechanically to maintain the level of PETCO2 between 4. 27 and 4. 93 kpa. NIBP,HR,SpO2 , ECG and EEG were recorded during anesthesia. According to TOF stimulation test intravenous atracurium 10-15 mg was given intermittently to maintain the ratio of T4/T1 less than 25%. Two channels EEG monitor was applied with the filtration range from 0 to 30 Hz Anesthesia level, adjusted at 0. 5,0. 8, 1. 0, 1. 3, 1. 5, 1. 3, 1. 0, 0.8 or 0. 5 MAC in sequence ,was maintained for 10 to 15 minutes before SEF (spectral edge frequency)and MPF (median power frequency) were recorded. NIBP decreased and HR increased with the inhaled agent concentration (IAC) level rising. The lowest BPs were 13. 1 /9. 33 kPa and 12. 9/8. 1kpa in both groups. There were negative remarkable correlations between either SEF or MPF and IAC in both groups (=- 0. 94 and -0. 82,P
