A portable medical device for sedating a patient includes a first vessel with a first substance contained under pressure and a second vessel with a second substance contained under pressure. A Y-valve may be provided with a first inlet, a second inlet, an outlet, a first pressure control valve between the first inlet and the outlet, and a second pressure control valve between the second inlet and the outlet. Tubes may connect the first and second vessels and a face mask to the Y-valve. The first pressure control valve may be opened to permit a fluid flow of the first substance from the first vessel to the face mask, and the second pressure control valve may be opened to permit a fluid flow of the second substance from the second vessel to the face mask.