Two-gas variable ratio, variable dose, metering system and method of use

摘要

A displacement metering device for administering a mixture of oxygen and an anesthetic gas to a patient measures single dose quantities of each of the two gases in separate sets of gas displacing means and dispenses a dose of each gas in admixture to a patient during the inspiration phase of the patient's respiratory cycle. Coordinating means ensure that the two gases are delivered in constant ratio and also provide means for changing the ratio between the two gases. Means are also provided to change the volume, or dose size, of the two administered gases.