Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-28T01:03:59.120Z Has data issue: false hasContentIssue false
  • English
  • Français

The influence of the α2-adrenoceptor agonist, clonidine, on the EEG and on the MAC of isoflurane

Published online by Cambridge University Press:  16 August 2006

H. M. M. El-Kerdawy ,
E. E. Van Zalingen  and
J. G. Bovill
H. M. M. El-Kerdawy
Affiliation:
Department of Anaesthesiology, Leiden University Medical Centre, Leiden, The Netherlands Present address: Department of Anaesthesia, University of Cairo, Cairo, Egypt.
E. E. Van Zalingen
Affiliation:
Department of Anaesthesiology, Leiden University Medical Centre, Leiden, The Netherlands
J. G. Bovill
Affiliation:
Department of Anaesthesiology, Leiden University Medical Centre, Leiden, The Netherlands
Get access

Abstract

We investigated the influence of intravenous clonidine 2, 4 and 6 μg kg−1 on the electroencephalogram and on the minimal alveolar concentration of isoflurane in 40 patients aged 20–60 years undergoing elective surgery. Minimal alveolar concentration was determined using the Dixon ‘up-and-down’ method. Thirty min after the clonidine infusion anaesthesia was induced with etomidate, 0.25 mg kg−1. Skin incision was made after stable end-tidal isoflurane concentrations had been maintained for at least 15 min. Clonidine caused significant decreases in the spectral edge (95%) and median power frequency of the electroencephalogram and in the bispectral index. The minimal alveolar concentration of isoflurane decreased in a dose-dependent manner from 1.32% (95% CI, 1.28%–1.36%) in the control group to 1.03% (0.9%–1.18%) in patients given clonidine 6 μg kg−1. Clonidine 4 and 6 μg kg−1 was associated with a moderate reduction in heart rate and arterial systolic blood pressure. We recommend the use of clonidine intravenously as an adjunct to general anaesthesia in a dose of 4 μg kg−1 given 15 min before induction of anaesthesia.

Keywords

alpha2-adrenoceptor agonistclonidineintravenousminimal alveolar concentrationiso-fluraneEEG
Type
Original Article
Information
European Journal of Anaesthesiology , Volume 17 , Issue 2 , February 2000 , pp. 105 - 110
Copyright
2000 European Society of Anaesthesiology

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)