Method and apparatus for administering anesthetics

A mask for administering anesthetic gas, said mask comprising:

• (a) an inner, cup-shaped mask body defining a cup-shaped cavity, said inner mask body including an inner opening having a central axis, an outer opening spaced from said inner opening along said central axis, and a continuous sidewall extending from said inner opening to said outer opening, said sidewall having a flexible edge defining the outer opening, said outer opening having a larger area than said inner opening and a shape adapted to engage the face of a patient in substantially gas-tight sealing relationship outwardly of the patient's nose and mouth;
• (b) an outer, cup-shaped body including an inner opening having a central axis, an outer opening larger than and spaced from said inner opening along said central axis and a second continuous sidewall having a shape corresponding with the shape of said inner body extending from said inner opening to said outer opening, said continuous sidewall having an outer edge defining the outer opening of the outer body;
• (c) said outer body and said inner body being arranged with said outer body surrounding but spaced from said inner body to define an extraction passageway therebetween bounded by the sidewalls of said inner and outer bodies, the outer opening of said outer body positioned relative to said central axis between the outer and inner openings of said inner body to thereby define an annular extraction slot between the edge of said inner body and the edge of said outer body, said inner opening of said outer body surrounding said inner opening of said inner body and communicating with said extraction slot through said extraction passageway;
• (d) deflecting means supported in said cup-shaped cavity opposite said inner opening for deflecting incoming fluid passing through said inner opening of said inner body outwardly at an angle to said central axis;
• and
• (e) coupling means for connection to said inner opening of said outer body to provide communication with an exhaust system and for connection to said inner opening of said inner body to provide communication with a source of pressurized anesthetic gas and with an exhaust system to withdraw gas exhaled by the patient.