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Perioperative use of α2-adrenoceptor agonists and the cardiac patient

Published online by Cambridge University Press:  01 March 2006

R. Aantaa  and
J. Jalonen
R. Aantaa
Affiliation:
University of Turku, Department of Anaesthesiology and Intensive Care, Turku, Finland Turku University Hospital, Department of Anaesthesiology and Intensive Care, Turku, Finland
J. Jalonen
Affiliation:
University of Turku, Department of Anaesthesiology and Intensive Care, Turku, Finland Turku University Hospital, Department of Anaesthesiology and Intensive Care, Turku, Finland
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Abstract

Summary

The centrally acting α2-adrenoceptor agonists clonidine and dexmedetomidine have been used with success to provide haemodynamic stability for patients undergoing surgery. Particularly in the case of patients with overt or underlying cardiac disease the actions of α2-adrenoceptor agonists, which include maintenance of stable systemic blood pressure and low heart rate and a reduction in overall oxygen consumption, can be expected to reduce the risk of procedure-related cardiac events. This expectation has been corroborated in clinical trials with clonidine, dexmedetomidine and mivazerol and meta-analyses; additional large controlled trials would be instructive in establishing a robust estimate of the scale of the benefit. In addition, α2-adrenoceptor agonists used as premedication have been shown to substantially reduce anaesthetic requirements among surgical patients, and the use of these agents has been associated with a reduced risk of postoperative delirium, which may be expected to improve considerably the postoperative course for at-risk patients. Dexmedetomidine is the only α2-adrenoceptor agonist currently approved for use in the intensive care unit. A distinctive feature of dexmedetomidine in that setting is that in addition to haemodynamic stability it confers a distinctive and advantageous quality of sedation: patients are tranquil but responsive to requests from attending staff. This review examines the pharmacological principles underlying the use of α2-adrenoceptor agonists as adjuncts to surgery and clinical experience in that indication.

Keywords

ADRENERGIC AGONISTS, α2, clonidine, dexmedetomidine, mivazerolSURGERY CARDIACCARDIOVASCULAR PHYSIOLOGY, blood pressure, heart rateSEDATIONANAESTHESIA GENERAL, anaesthetic requirements
Type
EACTA Review
Information
European Journal of Anaesthesiology , Volume 23 , Issue 5 , May 2006 , pp. 361 - 372
Copyright
2006 European Society of Anaesthesiology

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