Effect of Two Doses of Dexmedetomidine on Index of Consciousness and Permutation Entropy in Rabbits

Aura Silva, Almir P. Souza, Carlos Venâncio, David A. Ferreira, Luis Antunes

Abstract

The Index of Consciousness (IoC) and the Permutation Entropy (PE) are the most recent EEG-based indexes for depth of anesthesia monitoring but their use during ketamine or dexmedetomidine anesthesia has never been reported. In this study, the ability of these measures o differentiate between the effects of two different doses of dexmedetomidine combined with a fixed dose of ketamine in rabbits was studied. Five adult female rabbits received one of two ketamine/dexmedetomidine com-binations (15/0.025 and 15/0.05 mg/kg: G0.025 and G0.05, respectively). The effect of the two doses on IoC and PE were compared. The effect of dexmedetomidine dosage on the EEG was not significantly different between groups for any of the studied indexes (IoC (p=0.058); PE (p=0.392)). Only the IoC showed a significantly lower value in G0.05 than G0.025 at T15. The analysis revealed a significant effect of time on the IoC (p=0.001) and PE (p=0.0195). IoC and PE did not decrease to values correspondent to the anesthetized state, as was expected regarding previous works. This may be explained by the known excitatory effects of ketamine on the EEG. However, the tendency of the indexes to decrease after induction and to be lower in the animals that received the higher dexmedetomidine dosage suggests the capacity of these parameters to detect depressant effects of alpha-2-agonists.

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Paper Citation


in Harvard Style

Silva A., P. Souza A., Venâncio C., A. Ferreira D. and Antunes L. (2012). Effect of Two Doses of Dexmedetomidine on Index of Consciousness and Permutation Entropy in Rabbits . In Proceedings of the International Workshop on Veterinary Biosignals and Biodevices - Volume 1: VBB, (BIOSTEC 2012) ISBN 978-989-8425-94-2, pages 43-50. DOI: 10.5220/0003879100430050


in Bibtex Style

@conference{vbb12,
author={Aura Silva and Almir P. Souza and Carlos Venâncio and David A. Ferreira and Luis Antunes},
title={Effect of Two Doses of Dexmedetomidine on Index of Consciousness and Permutation Entropy in Rabbits},
booktitle={Proceedings of the International Workshop on Veterinary Biosignals and Biodevices - Volume 1: VBB, (BIOSTEC 2012)},
year={2012},
pages={43-50},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0003879100430050},
isbn={978-989-8425-94-2},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Workshop on Veterinary Biosignals and Biodevices - Volume 1: VBB, (BIOSTEC 2012)
TI - Effect of Two Doses of Dexmedetomidine on Index of Consciousness and Permutation Entropy in Rabbits
SN - 978-989-8425-94-2
AU - Silva A.
AU - P. Souza A.
AU - Venâncio C.
AU - A. Ferreira D.
AU - Antunes L.
PY - 2012
SP - 43
EP - 50
DO - 10.5220/0003879100430050