title: Beta-receptor antagonism does not fully explain esmolol-induced hypotension.
abstract: Esmolol is an ultra-short-acting beta-blocker that is widely used to lower blood pressure in acute settings intraoperatively and in patients with hypertension. Other beta-blockers have not been used in this way because of the belief that beta-blockers do not acutely lower blood pressure. The purpose of this study was to determine if esmolol has a hypotensive effect that is greater than other beta-blockers at similar degrees of beta-blockade. Esmolol, metoprolol, and propranolol were administered intravenously at three doses chosen to produce comparable degrees of beta-blockade. In spite of achieving comparable beta-blockade, esmolol produced a greater reduction in blood pressure than the other beta-blockers, implying that the hypotensive effect of esmolol cannot be accounted for simply by beta-blockade. There was no evidence to support a direct vasodilatory action of esmolol, and esmolol did not lower plasma norepinephrine concentrations.
authors.affiliation: Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN.
authors.forename: R
authors.initials: R
authors.lastname: Deegan
authors.forename: A J
authors.initials: AJ
authors.lastname: Wood
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D015444:Exercise; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008790:Metoprolol / Q000494:pharmacology; D009638:Norepinephrine / Q000097:blood; D011412:Propanolamines / Q000008:administration & dosage / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology
chemical_list: D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D011433:Propranolol; D008790:Metoprolol; C036604:esmolol; D009638:Norepinephrine