Dexmedetomidine modulates cardiovascular responses to stimulation of central nervous system pressor sites
| Autor: | Michael Staunton, David A. Schwabe, Enric Samso, Neil E. Farber, William T. Schmeling |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Bradycardia
Agonist Central Nervous System medicine.medical_specialty medicine.drug_class Stimulation Blood Pressure Pressoreceptors Cardiovascular System Heart Rate Receptors Adrenergic alpha-2 Internal medicine Heart rate medicine Animals Drug Interactions Dexmedetomidine business.industry Imidazoles Medetomidine Electric Stimulation Endocrinology Blood pressure Anesthesiology and Pain Medicine Anesthetic Anesthetics Inhalation Cats Halothane medicine.symptom business Adrenergic alpha-Agonists medicine.drug |
| Zdroj: | Anesthesia and analgesia. 88(3) |
| ISSN: | 0003-2999 |
| Popis: | UNLABELLED Halothane attenuates the alterations in arterial pressure (BP) and heart rate (HR) produced by central nervous svstem (CNS) stimulation. We examined the effects of the alpha2-adrenergic agonist dexmedetomidine, with and without halothane, on cardiovascular regulation during CNS pressor site stimulation in chronically instrumented cats. Stimuli trains via bipolar stimulating electrodes in the hypothalamus and reticular formation elicited pressor responses. Dexmedetomidine-induced (15 microg/kg PO) bradycardia was greater in the presence of halothane. CNS stimulation increased BP and HR, which were dose-dependently attenuated by halothane (hypothalamic stimulation 71 +/- 9 mm Hg at control, 25 +/- 5 and 15 +/- 3 mm Hg at 1.0% and 1.5% halothane, respectively). Although dexmedetomidine alone did not alter pressor responses, halothane plus dexmedetomidine attenuated pressor responses in a potentially synergistic fashion (hypothalamic stimulation 67 +/- 8 mm Hg at control, 2 +/- 1 and 1 +/- 0.4 mm Hg at 1.0% and 1.5% halothane, respectively). These results suggest differences in the disruptive effects of CNS-mediated cardiovascular responses by halothane and dexmedetomidine, and that dexmedetomidine has an anesthetic-sparing effect on these CNS-mediated cardiovascular control mechanisms, potentiating the depressant effect of halothane. IMPLICATIONS A new potential anesthetic adjunct, dexmedetomidine, does not attenuate brain-mediated increases in blood pressure, but the combination of dexmedetomidine and the anesthetic halothane acts to modulate central cardiovascular responses. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|