Effects of sedative and hypnotic drug combinations on transcranial magnetic motor evoked potential, bispectral index and ARX-derived auditory evoked potential index in dogs.
Relationships between onset latency and peak-to-peak amplitude of magnetic motor evoked potentials (MMEP) after transcranial magnetic stimulation (TMS), together with the electroencephalographic parameters bispectral analysis index (BIS) and the autoregressive model with exogenous input (ARX)-derived auditory evoked potential index (AAI) were explored during different sedative and hypnotic drug combinations in six dogs. TMS was performed under sedation with acepromazine/methadone or medetomidine and after a single bolus injection of propofol or etomidate. Data for BIS and AAI were continuously collected during the periods of treatment with the hypnotic drugs. Changes in BIS and AAI during both periods were not statistically correlated with changes in onset latencies and peak-to-peak amplitudes of MMEP after TMS. Therefore, both electroencephalographic techniques are of limited use in titrating sedation and anaesthesia during TMS in the dog.
Van Soens
Iris
I
Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. Iris.VanSoens@UGent.be
Struys
Michel M
MM
Polis
Ingeborgh E
IE
Tshamala
Mulenda
M
Nollet
Heidi
H
Bhatti
Sofie F
SF
Van Ham
Luc M
LM
D000075:Acepromazine / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D004285:Dogs / Q000502:physiology*; D018492:Dopamine Antagonists / Q000494:pharmacology; D004338:Drug Combinations; D005072:Evoked Potentials, Auditory / Q000187:drug effects*; D019054:Evoked Potentials, Motor / Q000187:drug effects*; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D008279:Magnetic Resonance Imaging; D020926:Medetomidine / Q000494:pharmacology; D008691:Methadone / Q000494:pharmacology; D009294:Narcotics / Q000494:pharmacology
D018492:Dopamine Antagonists; D004338:Drug Combinations; D006993:Hypnotics and Sedatives; D009294:Narcotics; D000075:Acepromazine; D020926:Medetomidine; D008691:Methadone