Related Experiment Video
Updated: Aug 13, 2026
Application of Dixon's Up-and-Down Design to Estimate the Minimum Alveolar Concentration of Sevoflurane in Rats with Refined Movement Classification
Published on: July 25, 2025
Clonidine premedication effects on inhaled induction with sevoflurane in adults: a prospective, double-blind,
T Watanabe1, Y Inagaki, Y Ishibe
1Department of Anesthesiology and Critical Care Medicine, Tottori University Faculty of Medicine, Yonago, Tottori, Japan.
Background:
The purpose of this study was to evaluate whether oral clonidine premedication becomes an alternative to N2O in terms of shortening the induction time and attenuation of the adrenergic response to tracheal intubation during inhalation induction with sevoflurane, and to evaluate the quality of anesthetic induction according to the patient's satisfaction.
Methods:
We studied 84 female patients who were randomly allocated into four study groups: Groups I and II received a placebo orally, and Groups III and IV received clonidine at 150 and 300 microg, respectively, 90 min before induction of anaesthesia. Patients were anesthetized using a triple-deep-breath technique with 5% sevoflurane in Groups I, III and IV, and with 60% N2O-5% sevoflurane in group II.
Results:
Induction time was significantly longer (P < 0.05) in Group I. Increases in mean blood pressure and heart rate after tracheal intubation were significantly suppressed in Groups III and IV but not in Group II compared with Group I. Comfort and impression of anesthesia was better in Groups III and IV than in Groups I and II.
Conclusion:
In volatile anesthetic induction, pre-anesthetic clonidine may become an alternative to N2O and may provide more comfort than with N2O.
Related Concept Videos
01:20Inhalational Anesthetics: Overview
01:24Parenteral Anesthetics: Overview
01:22Stages of General Anesthesia
01:23Sedatives and Hypnotics: Overview
Sedative-hypnotics are categorized into barbiturates, benzodiazepines (BZDs), and non-benzodiazepines or Z-drugs. These drugs work by suppressing central nervous system activity, and this suppression is dose-dependent. Older sedative medications, like barbiturates, follow a linear curve in...
01:17Sedatives and Hypnotics Drugs: Miscellaneous Agents
Melatonin congeners like ramelteon (Rozerem) and tasimelteon (Hetlioz) selectively bind to melatonin receptors (MT1 and MT2) and thus mimic the actions of melatonin, a hormone that regulates sleep-wake cycles. Tasimelteon is primarily used for non-24-hour sleep-wake disorder, common in blind patients. They are also used to treat conditions like insomnia...
01:24General Anesthesia: Overview
General anesthesia induces unconsciousness in the whole body, while the others target specific areas or sensations. It is administered to minimize adverse effects, maintain...