[Flumazenil and volatile anesthetics. Study of possible interferences in rats]

Many works suggest contradictory experimental or clinical results of flumazenil effects during inhalation anaesthesia. In ten rats anaesthesia was induced with 5% isoflurane or halothane during one minute and maintained during 5 minutes with 1% the same halogene anaesthetic in 50% N2O and O2. Then 0.2 mg of flumazenil or a same volume of placebo were administered intraperitoneally and during the last 5 minutes, the rats were exposed in 1% volatile anesthetic gas flow. Sleep times were measured in terms of reestablishment of the righting reflex. Each rat was anesthetized four time: halothane and isoflurane, with flumazenil or placebo. In those conditions, there were no significant changes in sleep times either the anaesthesia were associated, with flumazenil or with placebo.