Ventilating element, system, and methods
A manually operated ventilating element such as a bellows for administration of artificial respiration, for example, during anesthesia, has wall sections or pleats of different diameters. When the element is actuated through a small stroke length, the smaller section is actuated. A small volume of gas is delivered and the change in delivered volume per unit stroke length is small, so that the operator can precisely control the delivered volume. When the element is actuated through a larger stroke length, a larger volume per unit stroke length is delivered. The same element can be used to treat children and adults.
1. A ventilating element for use with a breathing apparatus, the element comprising a hollow body having a closed end, an open end and a plurality of wall sections between the ends, the body defining an interior space, the wall sections being movable in an output direction toward the open end to diminish the volume of the interior space and movable in an intake direction away from the open end to increase the volume of the interior space, the element further including a fitting disposed at the open end,
wherein the wall sections include a plurality of first wall sections disposed adjacent the open end, the plurality of first wall sections having a common first cross-sectional area and one or more second wall sections disposed adjacent the closed end, the one or more second wall sections having a second cross-sectional area less than the first cross-sectional area,
the ventilating element further including a closed-end plate disposed at the closed end of the body and mechanically connected to one of the one or more second wall sections adjacent the closed end, whereby the wall sections can be moved by manipulating the closed end plate, and a handle mechanically connected to the closed end plate,
wherein the fitting is constructed and arranged to connect the body with the breathing apparatus so that the open end of the body communicates with the breathing apparatus and so that the open end of the body is constrained against movement, and wherein the body is constructed and arranged so that without the need for an operator to select or adjust different controls, the operator can selectively either (i) manually move only the second wall sections without moving the first wall sections to pump a relatively small volume of gas per unit length of motion, or (ii) manually move the first wall sections to pump a relatively large volume of gas per unit length of motion.
2. A ventilating element as claimed in claim 1 wherein the body has an axis extending between the ends and the wall sections surround the axis.
3. A ventilating element as claimed in claim 1 wherein the fitting includes an open end plate mechanically connected to one of the plurality of first wall sections adjacent the open end.
4. A ventilating element as claimed in claim 1 wherein the wall sections include pleats formed from a flexible material.
5. A ventilating element as claimed in claim 1 wherein the first cross-sectional area is about 100 to about 160 cm 2 and the second cross-sectional area is about 30 to about 60 cm 2 .
6. A ventilating element as claimed in claim 1 wherein the wall sections include one or more third wall sections disposed between the first wall sections and the second wall sections, the third wall sections having cross-sectional area less than the first cross-sectional area but greater than the second cross-sectional area.
7. A breathing system including a breathing circuit, a machine chassis and a ventilating element as claimed in any of claim 1 , 2 , or 3 through 5 , the element being mechanically connected to the machine chassis so that the interior space within the body is in communication with the breathing circuit, so that the open end of the body is fixed to the machine chassis and so that the ventilating element is supported by the breathing machine chassis.
8. A system as claimed in claim 7 wherein the closed end of the body is disposed above the open end.
9. A ventilating element for a breathing apparatus comprising a unitary bellows defining an interior space, the bellows having a closed end, an open end, an axis extending between the ends and a plurality of pleats formed from a flexible material extending around the axis between the ends, the pleats including a plurality of large pleats having a common first diameter disposed adjacent the open end and one or more small pleats having a second diameter less than the first diameter disposed adjacent the closed end,
the element further including a closed end plate disposed at the closed end of the bellows and mechanically connected to one of the one or more small pleats adjacent the closed end, and a handle mechanically connected to the closed end plate;
the element further including a fitting disposed at the open end and mechanically connected to one of the plurality of large pleats adjacent the open end, the fitting being constructed and arranged to connect the bellows with the breathing apparatus so that the open end of the bellows communicates with the breathing apparatus and so that the open end of the bellows is constrained against movement, the bellows being constructed and arranged so that an operator can selectively either (i) manually move only the small pleats without moving the large pleats to pump a relatively small volume of gas per unit length of motion, or (ii) manually move the large pleats to pump a relatively large volume of gas per unit length of motion.