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I.v. clonidine: does it work as a hypotensive agent with inhalation anaesthesia?
1Department of Anaesthesia, Royal National Throat Nose and Ear Hospital, London, UK.
British Journal of Anaesthesia
|September 3, 1999
Summary
Clonidine, an intravenous hypotensive agent, significantly reduced the need for metoprolol during anesthesia. Further studies are needed to assess its safety during the recovery period.
Area of Science:
- Anesthesiology
- Pharmacology
Background:
- Intravenous hypotensive agents are crucial for managing blood pressure during anesthesia.
- Clonidine has shown potential hypotensive effects.
Purpose of the Study:
- To evaluate the efficacy of intravenous clonidine as a hypotensive agent during anesthesia.
- To compare the requirement for metoprolol in patients receiving clonidine versus placebo.
Main Methods:
- A double-blind, randomized, placebo-controlled study involving 41 patients.
- Patients received either clonidine (3 micrograms/kg) or placebo at anesthetic induction.
- Metoprolol was administered to maintain systolic arterial pressure at 80 mm Hg.
Main Results:
- The clonidine group required significantly less metoprolol (P < 0.00035).
- No significant differences in mean arterial pressure were observed between groups over time.
Conclusions:
- Intravenous clonidine may be a viable hypotensive agent during anesthesia.
- Additional data on recovery period safety are necessary to fully assess this technique.
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