Determination of the minimum alveolar concentration of sevoflurane that blunts adrenergic responses and the effect of a constant rate infusion of ketamine in sheep

Publication date: Available online 6 December 2019Source: Research in Veterinary ScienceAuthor(s): Michele Barletta, Jane E. Quandt, Rachel A. Reed, Erik H. Hofmeister, Kristen M. MessengerAbstractMinimizing sympathetic stimulation under anesthesia prevents activation of the neuroendocrine stress response. The minimum alveolar concentration blunting adrenergic responses in 50% of the population when exposed to a noxious stimulus is defined as MAC-BAR. The purpose of this study was to determine the MAC-BAR of sevoflurane (MAC-BARsevo) in sheep and the MAC-BAR sparing effects of ketamine.Thirteen healthy Dorset-cross adult ewes, 4 ± 1 year old and weighing 74 ± 9 kg, were enrolled in a randomized blinded crossover study design. Ewes were anesthetized twice for MAC-BARsevo determination. After face mask induction with sevoflurane, sheep received intravenous ketamine at 1.5 mg/kg and a constant rate infusion of 1.5 mg/kg/h or an equivalent volume of saline (placebo). After 8 day washout, the other treatment was administered. A bracketing technique was used for MAC-BARsevo determination and values were collected in duplicate. The mechanical stimulus (sponge forceps) was applied at the coronary band for 1 min and blood was collected for ketamine plasma concentrations. The MAC-BARsevo values of each treatment were compared using a paired t-test.Mean MAC-BARsevo of the ketamine and placebo were 2.73 ± 0.23% and 2.77 ± 0.31%, res...
Source: Research in Veterinary Science - Category: Veterinary Research Source Type: research

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Source: Anesthesiology - Category: Anesthesiology Source Type: research
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Source: Journal of Cardiothoracic and Vascular Anesthesia - Category: Anesthesiology Authors: Tags: Review Article Source Type: research
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Source: Cardiovascular Toxicology - Category: Cardiology Authors: Tags: Cardiovasc Toxicol Source Type: research
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Source: Medicine - Category: Internal Medicine Tags: Research Article: Observational Study Source Type: research
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This article is protected by copyright. All rights reserved. PMID: 31891193 [PubMed - as supplied by publisher]
Source: The Journal of Physiology - Category: Physiology Authors: Tags: J Physiol Source Type: research
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Source: Experimental Neurology - Category: Neurology Authors: Tags: Exp Neurol Source Type: research
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Source: BMC Pharmacology and Toxicology - Category: Drugs & Pharmacology Tags: BMC Pharmacol Toxicol Source Type: research
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Source: Health News from Medical News Today - Category: Consumer Health News Tags: Pain / Anesthetics Source Type: news
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