[Adsorption of volatile anesthetics on activated charcoal. Efficiency of an experimental filter during low-flow...

The inclusion of charcoal filters in the anaesthetic low-flow systems contributes to the acceleration of the kinetics of isoflurane (Forane). In fifty-four subjects, scheduled for extra- and intracranial surgery, ventilated with a low-flow system (Ohmeda Excel OAV7750 with rebreathing cassette) with a mean total flow of 0.7 1/min, the experimental charcoal cartridge showed: (a) a good adsorbent power (awakening within 5-6 minutes from the inclusion of the cartridge into the circuit) and (b) efficiency (adsorbent power unchanged until the sixth application). The use of charcoal during low-flow anaesthesia is both useful and economical.