A method and apparatus for preparing a required concentration of anaesthetic

摘要

893,006. Anaesthetic apparatus. HARTMANN & BRAUN A.G. Jan. 24, 1961 [Jan. 26, 1960], No. 2746/61. Class 81 (2). In order to prevent a patient receiving an excess of anaesthetic, the respirable gas is brought into contact with anaesthetic which has been adsorbed or dissolved. In one form of apparatus, a container 9 encloses active carbon 16 and is charged by passing anaesthetic gas through it from inlet 10 to outlet 11. These orifices may then be closed, by caps 13, 12, until the container is required for use when it is connected in the breathing circuit so that respirable gas passes through it, entraining the gas as it does so. In another form, the anaesthetic is dissolved in an oil and respirable gas is bubbled through it as it flows to the patient. In the latter case the concentration of anaesthetic is determined by an hydrometer but in a further modification further anaesthetic is added to the solution through a valve controlled by a float influenced by the specific gravity of the solution. In each case the total, quantity of anaesthetic administered may be predetermined and, owing to the slow release of anaesthetic from its container, the concentration is kept within safe limits.