Thoracic epidural anesthesia attenuates halothane-induced myocardial sensitization to dysrhythmogenic effect of epinephrine in dogs. Anesthesiology 1995 Jan;82(1):129-34
Date
01/01/1995Pubmed ID
7832294DOI
10.1097/00000542-199501000-00017Scopus ID
2-s2.0-0028861187 (requires institutional sign-in at Scopus site) 37 CitationsAbstract
BACKGROUND: The autonomic nervous system plays a critical role in the central modulation of cardiac dysrhythmias. Because sympathetic blockade by thoracic epidural anesthesia has been documented to protect patients from various stress responses, the authors speculate that epidural anesthesia can attenuate the dysrhythmogenic interaction between halothane and epinephrine.
METHODS: In adult mongrel dogs anesthetized with halothane, the dysrhythmogenic dose (DD) of epinephrine, defined as the smallest dose producing four or more premature ventricular contractions within a 15-s period, was determined in the presence of thoracic epidural mepivacaine or saline. To address the effect of circulating mepivacaine after epidural administration, the authors examined the DD of epinephrine in the presence of intravenous mepivacaine. They also investigated the effect of thoracic epidural anesthesia in bilaterally vagotomized dogs.
RESULTS: Epidural mepivacaine significantly increased the DD of epinephrine compared with epidural saline. However, intravenous mepivacaine did not affect the DD of epinephrine, even when the plasma concentration of mepivacaine during the dysrhythmias was twice that in the epidural mepivacaine group. The beneficial effect of epidural mepivacaine was not seen in bilaterally vagotomized dogs.
CONCLUSIONS: Thoracic epidural anesthesia attenuated the myocardial sensitization by halothane, and vagal activity had an essential role in this action.
Author List
Kamibayashi T, Hayashi Y, Mammoto T, Yamatodani A, Taenaka N, Yoshiya IAuthor
Tadanori Mammoto MD, PhD Associate Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Anesthesia, EpiduralAnimals
Arrhythmias, Cardiac
Dogs
Dose-Response Relationship, Drug
Drug Interactions
Epinephrine
Female
Halothane
Heart
Hemodynamics
Injections, Epidural
Injections, Intravenous
Male
Mepivacaine
Vagotomy