Effects of Sevoflurane on Central Nervous System Electrical Activity in Cats

• Published in: Anesthesia and analgesia Vol. 79; no. 1; pp. 52 - 57
• Main Authors: Osawa, Masami, Shingu, Koh, Murakawa, Masahiro, Adachi, Takehiko, Kurata, Jiro, Seo, Norimasa, Murayama, Takanori, Nakao, Shin-ichi, Mori, Kenjiro
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD International Anesthesia Research Society 01.07.1994; Lippincott
• Subjects: Anesthetics - pharmacology; Anesthetics. Neuromuscular blocking agents; Animals; Biological and medical sciences; Brain - drug effects; Brain - physiology; Cats; Electroencephalography - drug effects; Electrophysiology; Ethers - pharmacology; Evoked Potentials, Somatosensory - drug effects; Female; Male; Medical sciences; Methyl Ethers; Neuropharmacology; Pharmacology. Drug treatments; Reticular Formation - drug effects; Reticular Formation - physiology; Sevoflurane; Volatile compound; Fissipedia; Carnivora; Vertebrata; Mammalia; General anesthetic; Animal; Cat; Central nervous system; Electrophysiology; Electroencephalography
• ISSN: 0003-2999; 1526-7598
• DOI: 10.1213/00000539-199407000-00011

We analyzed the effect of a new volatile anesthetic, sevoflurane (2%-5% in oxygen) on the electroencephalogram (EEG) of the neocortex, amygdala, and hippocampus, cortical somatosensory evoked potential (SEP), and brainstem reticular multiunit activity (R-MUA) in cats. Sevoflurane suppressed the background activity of the neocortex more than the amygdala and hippocampus. With increasing concentration of sevoflurane, the cortical EEG progressed from high-amplitude slow waves to a suppression-burst pattern, which was followed by an isoelectric pattern and then spikes with isoelectricity. The amplitude of the SEP was augmented and the R-MUA was suppressed by sevoflurane in a dose-related manner. Repetitive peripheral electrical stimulation induced generalized seizures at 5% sevoflurane in 2 of 13 cats. These results suggest that sevoflurane suppresses the background central nervous system electrical activities in a dose-related manner, leaving the reactive capabilities facilitated at deep anesthesia.