System, apparatus and method for supplying gases

• US 10,099,026 B2
• Filed: 12/02/2011
• Issued: 10/16/2018
• Est. Priority Date: 12/03/2010
• Status: Active Grant

• Current Assignee: Fisher & Paykel Healthcare Limited
• Original Assignee: Fisher & Paykel Healthcare Limited
• Inventors: Rapoport, David M., Kuriger, Donald Roy, Arrowsmith, Mark John
• Primary Examiner(s): Dixon, Annette
• Application Number:
  US13/991,131
• Publication Number:
  US 20140000610A1
• Time in Patent Office: 2,510 Days
• Field of Search: 12820222, 12820418, 12820421, 12820422, 12820423, 12820426, 12820524, 12820525
• CPC Class Codes: A61M 16/0057 Pumps therefor
• CPC Class Codes: A61M 16/0066 Blowers or centrifugal pumps
• CPC Class Codes: A61M 16/0069 the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/0816 Joints or connectors
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/20 Valves specially adapted to medical respiratory devices
• CPC Class Codes: A61M 16/208 Non-controlled one-way valves, e.g. exhalation, check, pop-off non-rebreathing valves
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/3653 by Joule effect, i.e. electric resistance
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards

Abstract

A system, apparatus and methods are provided for supplying gases to a user. The supply includes a sub-therapeutic mode and a pressure support mode for delivering therapy to a user. A flow diversion device or valve switches from a first mode corresponding with the sub-therapeutic mode of the system to a second mode corresponding with the pressure support mode of the system. In the first mode, the valve opens a larger flow path between the interior of the user interface and ambient air than in the second mode.

Claims

1. An apparatus comprising:

a flow generator,

a controller connected to the flow generator to control output of the flow generator,

a conduit extending from the flow generator to connect with a user interface, an inside of the conduit and an inside of the user interface defining a gases space, and

a valve positioned at or adjacent the user interface and in a flow path between the flow generator and a user, the valve being switchable between a first mode in which the gases space is significantly open to ambient through the valve and a second mode in which the gases space is not significantly open to ambient through the valve, the valve including a valve member, a flow passage at least partially defined by a wall, and a gap between the valve member and the wall, wherein the valve is not actively controlled by the controller and wherein the valve is configured to be responsive to change in the output of the flow generator;

the controller comprising one or more positive airway pressure support modes in which the controller is adapted to cause the flow generator to deliver pressure support to an airway of a user with the valve in the second mode, and

the controller comprising one or more sub-therapeutic modes in which the controller is adapted to cause the flow generator to deliver flow of gases to the user with the valve in the first mode,

wherein, with the valve in the first mode and the controller operating in the sub-therapeutic mode, the valve remains stable for flows up to at least about 20 liters per minute with delivered pressures below about 2 cm H2O.

2. The apparatus of claim 1, wherein the valve includes an aperture communicating the gases space with ambient and a valve member that in a second position substantially closes the aperture and is substantially out of a flow path of gases through an portion of the gases space in which the valve is position, and the valve member in a first position leaving the aperture substantially open for substantially unimpeded flow from the user interface to ambient.

3. The apparatus of claim 2, wherein in the first position the valve member partially, but not fully, occludes flow from the flow generator to the user interface.

4. The apparatus of claim 3, wherein the valve member, when in the first position, occludes between about 50% and about 80% of a cross-sectional area of a flow path from the flow generator to the user interface.

5. The apparatus of claim 1, wherein the first position of the valve comprises a valve member of the valve being bent towards the user interface when the user is inhaling.

6. The apparatus of claim 1, wherein the first position of the valve comprises a valve member of the valve being bent towards the flow generator when the user is exhaling.

7. The apparatus of claim 1, wherein the one or more positive airway pressure support modes comprises a supply of gases to the user such that, with the valve in the first mode, the flow generator provides enough flow to the user interface such that, with the user interface worn by a user, a pressure greater than about 3 cm H2O is produced.

8. The apparatus of claim 1 including a sensor adapted to derive a measure of pressure in the gases space such that, in a positive airway pressure mode, the controller controls output of the flow generator according to a command pressure and feedback from the sensor.

9. The apparatus of claim 1, wherein, in the one or more sub-therapeutic modes, the controller controls output of the flow generator to provide a flow to the user interface that is not sufficient to force the valve into the second mode.

10. The apparatus of claim 9 wherein, in the one or more sub-therapeutic modes, the controller causes the flow generator to provide a flow greater than about 5 liters per minute.

11. The apparatus of claim 9, wherein, in the one or more sub-therapeutic mode, the controller causes the flow generator to provide a flow less than about 20 liters per minute.

12. The apparatus of claim 1, wherein the valve moves from the first mode to the second mode upon rising through a first threshold of flow/pressure, and from the second mode to the first mode on falling through a second threshold of flow/pressure, wherein the first threshold of flow/pressure is higher than the second threshold of flow/pressure.

13. The apparatus of claim 1, wherein, with the valve in the second mode and the controller operating in the pressure support mode, the valve remains stable at pressures down to about 3 cm H2O or lower.

14. The apparatus of claim 13, wherein the lowest pressure for which the valve is stable in the second mode when the controller is in the pressure support mode is less than about 1 cm H2O above the average delivered pressure when the valve is in the first mode and the controller is in the one or more sub-therapeutic mode supplying about 15 liters per minute.

17. The apparatus of claim 1, further comprising an aperture in the wall of the conduit between the valve and the user interface, wherein the aperture is located about 5 mm to about 100 mm downstream of the valve.

18. The apparatus of claim 17, wherein the aperture is approximately trapezoidal in perimeter shape with a shorter of two parallel sides being closer to the valve.

15. The apparatus of 1, wherein, in the one or more sub-therapeutic mode, the controller controls the flow generator to deliver an average flow at a level that assures flushing of the user interface but which does not trigger the valve to switch from the first mode to the second mode.

16. The apparatus of 1, wherein the controller controls the flow generator to provide an average flow over multiple breaths that is substantially constant.

19. A valve for use at or adjacent a user interface, the valve comprising:

a flow passage at least partially defined by a wall, the flow passage extending between an inlet and an outlet that is adapted to be fluidly connected to the user interface;

an aperture defined through the wall, the aperture being positioned between the inlet and the outlet; and

a valve member being positioned between the inlet and the aperture, the valve member being movable between a first position and a second position, the valve member in the second position closing the aperture, the valve member in the first position leaving the aperture open for flow to ambient, the valve member in the first position partially but not fully occluding flow through the flow passage, and the valve member in the first position occluding between about 50% and about 80% of a cross section area of the flow passage in a location correlating to the valve member, wherein the valve member is not actively controlled by a controller and wherein the valve member is configured to be responsive to change in the output of a flow generator;

wherein a portion of a perimeter of the valve member and an inner surface of wall is separated by a gap, and

wherein, with the valve in the first position, the valve remains stable for flows up to at least about 20 liters per minute with delivered pressures below about 2 cm H2O.

20. A valve as claimed in claim 19, wherein a cross-sectional area of the flow passage at the location correlating to the valve member is between about 350 mm2 and about 600 mm2.

21. A valve as claimed in claim 20, wherein the area of the aperture is between about 10% and about 50% of the cross sectional area of the flow passage at the location correlating to the valve.

22. A valve as claimed in claim 21, wherein the area of the aperture is between about 15% and about 25% of the cross sectional area of the flow passage through the valve.