The divergent actions of volatile anaesthetics on background neuronal activity and reactive capability in the central nervous system in cats

Abstract

The effects of halothane, isoflurane, and enflurane on background neuronal activity and reactive capability in the central

Comparative effects of halothane, isoflurane, sevoflurane and desflurane on the electroencephalogram of the rat

“…The suppressive actions of halothane, sevoflurane and isoflurane on the response capability of the midbrain reticular formation to peripheral nerve stimulation in cats have also been compared (Tsushima et al 1998). In accordance with the previous study (Ogawa et al 1992), halothane caused less suppression of basal EEG activity, but had a greater effect on the response capability to peripheral stimulation than isoflurane or sevoflurane.…”

“…The position of isoflurane in this schema is at odds with the relative potency as defined by MAC value, a measure determined by antinociceptive efficacy in a rigorous test model (Urban & Bleckwenn 2002). Ogawa et al (1992) studied background electrical activity in midbrain reticular cells during volatile agent anaesthesia in cats as well as reactive capability by evoked responses in the visual neuronal pathway.…”

Anticonvulsant effects of sevoflurane on amygdaloid kindling and bicuculline-induced seizures in cats: comparison with isoflurane and halothane

“…This result is consistent with our previous report of the proconvulsant effects of large concentrations of sevoflurane in cats [4]. Isoflurane also induced spontaneous sporadic spikes on EEGs in cats [18,20], but it did not induce photic stimulationinduced spikes on EEG nor did it augment the photic stimulation-evoked potential in the visual cortex [20]. Therefore, sevoflurane, but not isoflurane, has a proconvulsant effect, and its proconvulsant effect may mask the anticonvulsant effects in this model of epilepsy.…”

Use of the bispectral index as a monitor of anesthetic depth in cats anesthetized with isoflurane

“…This EEG pattern has been described in cats and other species that received high concentrations of inhalant anesthetics 30,[32][33][34] and is associated with phasic activation of the reticular formation in the brain stem. 33 Spiking characteristics of the EEG result in an increase in the BIS value (range, 15 to 35) and may interfere with the correct interpretation of the BIS at high ET isoflurane concentrations.…”