VALVED HOLDING CHAMBER FOR USE WITH DRY POWDER INHALER
A valved holding chamber includes a holding chamber adapted to contain a substance and having an input end adapted to receive a dry powder inhaler, an output end and an interior volume defined between the input end and output end. An inhalation valve is disposed at the output end of the holding chamber and is moveable to an open position in response to an inhalation flow through the interior space. A vacuum generator, expandable volume and/or positive pressure may be used to draw medication from the dry powder inhaler into the holding chamber. Methods of using and assembling the system are also provided.
1 . A valved holding chamber comprising:
a holding chamber adapted to contain a substance and comprising an input end adapted to receive a dry powder inhaler, an output end and an interior volume defined between the input end and output end;
an inhalation valve disposed at the output end of the holding chamber and moveable to an open position in response to an inhalation flow through the interior space; and
a vacuum generator in fluid communication with the interior space, wherein the vacuum generator is configured to create a vacuum in the interior space.
2 . The valved holding chamber of claim 1 wherein the interior volume comprises a main chamber separated from an ante chamber by a release valve, wherein the vacuum generator is in fluid communication with the main chamber such that the vacuum is created in the main chamber, and wherein the ante chamber is in fluid communication with the input end.
3 . The valved holding chamber of claim 2 wherein the vacuum generator comprises a retractable piston.
4 . The valved holding chamber of claim 3 wherein the retractable piston is disposed in the main chamber.
5 . The valved holding chamber of claim 3 wherein the retractable piston is disposed in an auxiliary chamber in fluid communication with the main chamber.
6 . The valved holding chamber of claim 2 wherein the release valve is coupled to an actuator, wherein the release valve is moveable in response to an input from the actuator from a closed position, wherein the release valve separates the main chamber and the ante chamber, and an open position, wherein the main chamber is in fluid communication with the ante chamber.
7 . The valved holding chamber of claim 2 wherein the vacuum generator comprises a pump.
8 . The valved holding chamber of claim 7 wherein the pump comprises a manual pump.
9 . The valved holding chamber of claim 7 wherein the pump comprises an electric pump.
10 . The valved holding chamber of claim 2 wherein the vacuum in the main chamber comprises a minimum of −10 cmH2O to −40 cmH2O.
11 . The valved holding chamber of claim 11 wherein the vacuum in the main chamber is less than or equal to −821 cmH2O.
12 . The valved holding chamber of claim 2 further comprising a flow resistor disposed between the input end and the main chamber.
13 . The valved holding chamber of claim 2 further comprising at least one auxiliary air inlet in fluid communication with the main chamber.
14 . A valved holding chamber comprising:
a holding chamber adapted to contain a substance and comprising an input end adapted to receive a dry powder inhaler, an output end and an expandable interior volume defined between the input end and output end;
an inhalation valve disposed at the output end of the holding chamber and moveable to an open position in response to an inhalation flow through the interior volume; and
an expander coupled to the holding chamber, wherein the expander is moveable from a first configuration, wherein the expandable interior volume comprises a first interior volume, and a second configuration, wherein the expandable interior volume comprises a second interior volume, wherein the second interior volume is greater than the first interior volume.
15 . The valved holding chamber of claim 14 wherein the expander comprises a piston disposed in the interior volume.
16 . The valved holding chamber of claim 15 further comprising a spring biasing the piston from a first position, wherein the piston defines in part the first interior volume, to a second position, wherein the piston defines in part the second interior volume.
17 . The valved holding chamber of claim 16 further comprising an actuator coupled to the piston and/or spring, wherein the actuator is configured to release the spring so as to bias the piston from the first position to the second position.
18 . The valved holding chamber of claim 15 wherein the piston is disposed in the main chamber.
19 . The valved holding chamber of claim 18 wherein the piston comprises a one-way valve.
20 . The valved holding chamber of claim 19 wherein the one-way valve comprises a first one-way valve, and further comprising a second one-way valve disposed at the input end.
21 . The valved holding chamber of claim 15 wherein the retractable piston is disposed in an auxiliary chamber in fluid communication with the main chamber.
22 . The valved holding chamber of claim 15 wherein the retractable piston comprises a pull handle configured to be grippable by a user.
23 . The valved holding chamber of claim 14 wherein the expander comprises a collapsible wall defining in part the holding chamber.
24 . The valved holding chamber of claim 23 wherein the collapsible wall comprises telescoping sections.
25 . The valved holding chamber of claim 23 wherein the collapsible wall comprises pleats.
26 . The valved holding chamber of claim 23 wherein the collapsible wall comprises a deformable elastic side wall defining the holding chamber.
27 . The valved holding chamber of claim 18 wherein the expander further comprises a collapsible wall disposed inside the chamber housing, wherein a first end of the collapsible wall is coupled to the input end of the chamber housing and a second end of the collapsible wall is coupled to the piston, wherein the collapsible wall defines the expandable interior volume.
28 . The valved holding chamber of claim 27 further comprising a backpiece coupled to and connecting the input end of the chamber housing and the first end of the collapsible wall, wherein the backpiece comprises an opening configured to receive the dry powder inhaler.
29 . The valved holding chamber of claim 28 wherein the backpiece comprises a one-way inhalation valve in communication with the expandable interior volume defined by the collapsible wall.
30 . The valved holding chamber of claim 27 wherein the output end of the holding chamber comprises a one-way exhaust valve positioned upstream of the piston.
31 - 45 . (canceled)