Faculty Collaboration Database

Vascular responsiveness to brachial artery infusions of phenylephrine during isoflurane and desflurane anesthesia. Anesth Analg 2002 May;94(5):1137-40, table of contents

Date

04/26/2002

Pubmed ID

11973175

DOI

10.1097/00000539-200205000-00014

Scopus ID

2-s2.0-0036241718 (requires institutional sign-in at Scopus site)   4 Citations

Abstract

UNLABELLED: Compared with equi-minimum alveolar anesthetic concentration (MAC) isoflurane, desflurane is associated with greater levels of sympathetic nerve activity in humans but similar reductions in blood pressure. To explore these divergent effects, we evaluated vascular alpha(1)-adrenoceptor responses in the human forearm during isoflurane and desflurane anesthesia to determine if alpha(1)-adrenoceptor responses were more substantially attenuated during desflurane administration. Bilateral forearm venous occlusion plethysmography was used to examine arterial blood flow and to determine changes in forearm vascular resistance during brachial artery infusions of saline and phenylephrine (0.2, 0.4, 0.8, and 1.6 microg/min) in 22 conscious subjects and during anesthesia with 0.65 and 1.3 MAC isoflurane or desflurane. Infusion of phenylephrine into the brachial artery increased the forearm vascular resistance in a dose-dependent manner. The arterial response to phenylephrine was significantly attenuated by 0.65 and 1.3 MAC desflurane and similarly attenuated during 1.3 MAC isoflurane (P < 0.05). Impaired arterial alpha(1)-adrenoceptor responsiveness occurred during desflurane. However, this effect was statistically similar (P > 0.05) to the impaired responses during isoflurane. Blood pressure decreases during volatile anesthesia may be, in part, caused by decreased alpha(1)-adrenoceptor responsiveness.

IMPLICATIONS: alpha-receptors on blood vessels regulate constriction and dilation and therefore modulate blood pressure. This research indicates that vasoconstriction via the alpha(1)-receptor vascular response is impaired during isoflurane and desflurane anesthesia.

Author List

Arain SR, Williams DJ, Robinson BJ, Uhrich TD, Ebert TJ

Author

Thomas J. Ebert MD, PhD Adjunct Professor in the Anesthesiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adrenergic alpha-Agonists
Adult
Anesthetics, Inhalation
Brachial Artery
Female
Forearm
Humans
Isoflurane
Male
Phenylephrine
Receptors, Adrenergic, alpha-1
Vascular Resistance