Dexmedetomidine low dose followed by constant rate infusion and antagonism by atipamezole in isoflurane-anesthetized cats: an echocardiographic study.

Autor: Carvalho ER; Department of Veterinary Medicine, Federal University of Fronteira Sul, Realeza, PR, Brazil. Electronic address: beth_rcarvalho@hotmail.com., Champion T; Department of Veterinary Medicine, Federal University of Fronteira Sul, Realeza, PR, Brazil., Ambrosini F; Department of Veterinary Medicine, Federal University of Fronteira Sul, Realeza, PR, Brazil., da Silva GA; Department of Veterinary Medicine, Federal University of Fronteira Sul, Realeza, PR, Brazil., Freitas GC; Department of Veterinary Medicine, Federal University of Fronteira Sul, Realeza, PR, Brazil., D'Otaviano de Castro Vilani RG; Laboratory of Veterinary Anesthesia and Analgesia, Federal University of Paraná, Curitiba, PR, Brazil.
Jazyk: angličtina
Zdroj: Veterinary anaesthesia and analgesia [Vet Anaesth Analg] 2019 Jan; Vol. 46 (1), pp. 43-54. Date of Electronic Publication: 2018 Sep 27.
DOI: 10.1016/j.vaa.2018.09.040
Abstrakt: Objective: To investigate the effects of a low dose of dexmedetomidine (DEX) followed by constant rate infusion (CRI) and reversal with atipamezole on systolic and diastolic functions in isoflurane-anesthetized healthy cats.
Study Design: Prospective cohort study.
Animals: A group of 11 client-owned adult cats.
Methods: Baseline transthoracic echocardiography (TTE) was performed, followed by intramuscular (IM) administration of DEX (5 μg kg -1 ). After 10 minutes, sedation was scored, adverse effects were recorded and another TTE performed. Approximately 40 minutes after DEX administration, anesthesia was induced by isoflurane mask and maintained with 1.2% end-tidal isoflurane and DEX CRI (1 μg kg -1  hour -1 ) for 80 minutes. Physiological variables were recorded every 10 minutes, and TTE was repeated 10, 30 and 60 minutes after the start of anesthesia. CRI was stopped, atipamezole (30 μg kg -1 ) was administered IM and a final TTE was performed after 10 minutes. Repeated measures over time were submitted to one-way analysis of variance or Kruskal-Wallis test according to data distribution; significance was assumed at p < 0.05.
Results: After DEX premedication, mild sedation and a slight but significant increase in systolic arterial pressure occurred, and vomiting was a common adverse effect. The cardiac output (CO) and heart rate decreased during anesthesia, with no changes after administration of atipamezole. Trivial valvular insufficiencies were commonly seen after DEX premedication and during CRI. Myocardial radial and longitudinal systolic functions were not affected by sedation or by anesthesia. The late phase of diastole on both right and left ventricles was affected by isoflurane-DEX CRI. Global left ventricular myocardial performance was not impaired.
Conclusions: and clinical relevance Decreased CO and late diastolic impairment were observed in healthy cats administered a low dose of DEX for premedication followed by anesthesia with isoflurane and DEX CRI.
(Copyright © 2018 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)
Databáze: MEDLINE