Apparatus and method for controlled delivery of a breathing gas to the respiratory tracts of a user

• US 9,486,599 B2
• Filed: 04/06/2009
• Issued: 11/08/2016
• Est. Priority Date: 04/30/2008
• Status: Active Grant

• Current Assignee: ResMed Pty Ltd. (ResMed Incorporated)
• Original Assignee: ResMed R&D Germany GmbH (ResMed Incorporated)
• Inventors: Schaetzl, Stefan
• Primary Examiner(s): Philips, Bradley
• Assistant Examiner(s): BRYANT, ERIC C
• Application Number:
  US12/736,692
• Publication Number:
  US 20110108033A1
• Time in Patent Office: 2,773 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: A61M 16/0066 Blowers or centrifugal pumps
• CPC Class Codes: A61M 16/0666 Nasal cannulas or tubing devices for improving normal breathing through the nose A61F5/08; nose filters A62B23/06; outside holding devices A61M25/02
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/202 electrically actuated
• CPC Class Codes: A61M 2016/0027 pressure meter

Abstract

An apparatus for controlled delivery of a flow of breathing gas to the respiratory tracts of a user includes a blower unit adapted to provide a gas flow, a nasal cannula with first and second outlets, and first and second gas paths connecting the blower unit to the first and second outlets, respectively. The Characteristics of the gas flow through each outlet can be controlled, sensed and/or adjusted independently.

Claims

1. An apparatus for controlled delivery of a flow of breathing gas to the respiratory tracts of a user, said apparatus comprising:

a blower unit adapted to provide a gas flow; and

a nasal cannula with first and second outlets, and first and second gas paths connecting the blower unit to the first and second outlets, respectively, wherein

the nasal cannula is configured so that characteristics of the gas flow through each outlet are independently controllable, are independently adjustable and are independently sensed, and

a control unit to control the apparatus to interchange between providing the gas flow to the respiratory tracts of the user through (a) the first gas path to the first outlet and (b) the second gas path to the second outlet, so as to permit providing of the gas flow from the blower unit through one of the outlets while not providing the gas flow from the blower unit through the other one of the outlets, and to adjust at least one characteristic of the provided gas flow while detecting, via one of the first or second outlets through its respective gas path not receiving the gas flow, at least one dynamic signal resulting from a respiratory cycle of the user.

2. The apparatus according to claim 1, wherein the characteristics of the gas flow comprise a flow rate and/or a pressure of the gas flow.

3. The apparatus according to claim 1, wherein the first and/or second gas path comprises a valve.

4. The apparatus according to claim 1, wherein the first and/or second gas path comprises a pressure sensor.

5. The apparatus according to claim 1, wherein functions of the first and second gas paths are interchanged periodically.

6. The apparatus according to claim 5, wherein the period of interchange is adjusted to the respiratory cycle of the user.

7. The apparatus according to claim 1, wherein the nasal cannula is adapted not to seal with the user'"'"'s face and/or nostrils and/or wherein the apparatus is adapted to be used in an open CPAP system.

8. The apparatus according to claim 4, further comprising a humidifier positioned upstream of the first and second gas paths, the humidifier being configured to adjust a humidity and a temperature of the gas in the first and second gas paths.

9. The apparatus according to claim 8, wherein each pressure sensor is connected to a respective gas flow path through a filter configured to protect said pressure sensor from condensing water.

10. The apparatus according to claim 9, wherein the filter is a diaphragm filter.

11. The apparatus according to claim 1, wherein the apparatus is configured to detect a condition of an upper airway of the user based on the at least one dynamic signal, wherein the condition of the upper airway of the user is indicative of a flow limitation.

12. The apparatus according to claim 11, wherein the apparatus is configured to adjust at least one characteristic of the provided gas flow based on a number of flow limitations per unit of time.

13. The apparatus according to claim 12, wherein the at least one dynamic signal is a pressure signal.

14. The apparatus according to claim 1, wherein the apparatus is adapted to provide the gas flow to the respiratory tracts of the user through one of the first and second gas paths in response to a pressure change indicated by the at least one dynamic signal.

15. The apparatus according to claim 14, wherein the apparatus is adapted to provide the gas flow to the respiratory tracts of the user through one of the first and second gas paths when the pressure is above a predetermined threshold.

16. The apparatus according to claim 15, wherein the apparatus is adapted to terminate the gas flow to the respiratory tracts of the user when no dynamic signal is detected for a predetermined amount of time.

17. The apparatus according to claim 1, wherein the apparatus is adapted to provide the gas flow to the respiratory tracts of the user through one of the first and second gas paths in response to an inspirational flow indicated by the at least one dynamic signal.

18. The apparatus according to claim 17, wherein the at least one dynamic signal indicates the inspirational flow when the dynamic signal is above a first predetermined threshold.

19. The apparatus according to claim 18, wherein the first predetermined threshold is set to a high, medium or low sensitivity.

20. The apparatus according to claim 19, wherein the apparatus is adapted to reduce a flow rate of the gas flow provided to the respiratory tracts of the user when the at least one dynamic signal indicates an expirational flow.

21. The apparatus according to claim 20, wherein the at least one dynamic signal indicates the expirational flow when the dynamic signal is below a second predetermined threshold.

22. The apparatus according to claim 21, wherein the apparatus is adapted to provide the gas flow to the respiratory tracts of the user through both of the first and second gas paths while the user is in expiration.

23. The apparatus according to claim 1 wherein the control unit includes a screening process to detect flow limitation and a flow controlling process to respond to the detected flow limitation by adjusting applied gas flow rate to pneumatically splint an obstructed airway with at least one of the first or second outlets.

24. A method of controlling an apparatus for controlled delivery of a flow of breathing gas, wherein the apparatus comprises a blower unit adapted to provide a gas flow;

and a nasal cannula with first and second outlets, and first and second gas paths connecting the blower unit to the first and second outlets, respectively, wherein the nasal cannula is configured so that characteristics of the gas flow through each outlet are independently controllable, are independently adjustable and are independently sensed, and a control unit to control the apparatus to interchange between providing the gas flow to the respiratory tracts of the user through (a) the first gas path to the first outlet and (b) the second gas path to the second outlet, so as to permit providing of the gas flow from the blower unit through one of the outlets while not providing the gas flow from the blower unit through the other one of the outlets, and to adjust at least one characteristic of the provided gas flow while detecting, via one of the first or second outlets through its respective gas path not receiving the gas flow, at least one dynamic signal resulting from a respiratory cycle of the user;

said method comprising the following steps;

a) providing a first gas flow in the first gas path;

b) detecting a dynamic pressure signal in the second gas path; and

c) adjusting a characteristic of the first gas flow in response to the detected dynamic pressure signal,

wherein steps a) to c) are performed simultaneously.

25. The method according to claim 24, wherein steps a) to c) are performed repeatedly.

26. The method according to claim 25, wherein the function of the first and second gas paths are interchanged after each repetition.

27. The method of claim 24, wherein the apparatus is an open CPAP system.

28. A method of delivering a flow of breathable gas to the respiratory tracts of a user via a nasal cannula with first and second outlets, said method comprising the following steps:

a) selectively providing the flow of breathable gas to the respiratory tracts of a user through the first outlet and the second outlet so as to interchangeably provide the flow through one of the outlets while not providing the flow through the other one of the outlets;

b) measuring a dynamic pressure signal in a gas path connected to the one of the first and second outlets when not receiving the flow of breathable gas; and

c) adjusting a parameter of the flow of breathable gas in response to the measured dynamic pressure signal,

wherein steps a) to c) are performed simultaneously.

29. The method according to claim 28, wherein steps a) to c) are performed repeatedly.

30. The method according to claim 29, wherein functionalities of the first and second outlets are interchanged after each repetition.

31. The method according to claim 28, wherein the method further comprises humidifying and adjusting a temperature of the flow of breathable gas.

32. The method according to claim 28, further comprising:

d) analyzing the dynamic pressure signal to detect flow limitations; and

e) adjusting a parameter of the gas flow depending on frequency of detected flow limitations.

33. The method according to claim 32, wherein the parameter of the gas flow is one of:

a flow rate of the gas flow, and a pressure of the gas flow.

34. The method according to claim 28 wherein a screening process detects flow limitation and a flow controlling process responds to the detected flow limitation by adjusting applied gas flow rate to pneumatically splint an obstructed airway with at least one of the first or second outlets.