MECHANICAL VENTILATION IN THE PRESENCE OF SLEEP DISORDERED BREATHING

• US 20110284003A1
• Filed: 08/01/2011
• Published: 11/24/2011
• Est. Priority Date: 12/29/2003
• Status: Active Grant

• Current Assignee: ResMed Pty Ltd. (ResMed Incorporated)
• Original Assignee: Resmed Limited (ResMed Incorporated)
• Inventors: Ujhazy, Anthony John, Richards, Glenn, Buckley, Mark David, Schindhelm, Klaus Henry, DOUGLAS, Robert
• Granted Patent: US 8,683,999 B2
• Time in Patent Office: Days
• US Class Current: 128/204.23
• CPC Class Codes: A61B 5/4818 Sleep apnoea
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61M 16/0051 with alarm devices
• 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 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/06 Respiratory or anaesthetic masks
• CPC Class Codes: A61M 16/0875 Connecting tubes
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/15 Detection of leaks

Abstract

A method for controlling operation of a CPAP apparatus. The apparatus has a blower, a patient interface, an air delivery conduit for delivering air from the blower to the patient interface, a sensor for determining the pressure in the patient interface, and a control mechanism that causes air to be delivered at a desired pressure to the patient interface and that detects transitions between inhalation and exhalation of a respiratory cycle of a patient in order to synchronise the blower output with the patient'"'"'s efforts. In one form the CPAP apparatus provides pressure in accordance with a bi-level waveform with at least one characterising parameter of the waveform being automatically adjusted in accordance with indications of sleep disordered breathing. The indications of sleep disordered breathing can be one or more of snoring, apnea, hypopnea, and flow limitation.

Claims

1-18. -18. (canceled)

19. A method for controlling bi-level delivery of pressurized air to a patient comprising the steps of:

capturing a signal representing the patient'"'"'s respiratory cycle,

delivering pressurized air based on said respiratory cycle and a pressure-time template encompassing a first treatment pressure and a second treatment pressure,

determining the extent of any leak,

determining the presence of any flow flattening in the patient'"'"'s respiratory cycle,

determining the presence of any apnea or hypopnea, and

adjusting at least one of said first treatment pressure and said second treatment pressure based on the extent of said leak, the presence of any flow flattening in the patient'"'"'s respiratory cycle, and the presence of apnea or hypopnea;

wherein said method is implemented by a bi-level ventilation device comprised of a controller, blower, patient interface, and flow sensor.

20. The method of claim 19 in which said template is one of a square wave and a shark-fin wave.

21. The method of claim 19 in which said template has a maximum allowable swing between said first treatment pressure and sais second treatment pressure.

22. The method of claim 19 wherein the first treatment pressure is decreased in the absence of an indication of apnea, hypopnea, and snoring.

23. The method of claim 19 wherein the second treatment pressure is decreased in the absence of any indication of flow flattening and snoring.

24. The method of claim 19 wherein said pressure-time template is stored in look-up tables or arrays.

25. A ventilatory apparatus for delivering pressurized air to a patient comprising:

a blower,

a controller,

a patient interface, and

a flow sensor;

wherein said apparatus (1) delivers pressurized air according to the patient'"'"'s respiratory cycle and a pressure-time template encompassing a first treatment pressure and a second treatment pressure;

(2) determines the patient'"'"'s respiratory cycle, the extent of any leak, the presence of any flow flattening, and the presence of any apnea or hypopnea; and

(3) adjusts said first treatment pressure and said second treatment pressure based on the determined extent of said leak, presence of flow flattening, and presence of any apnea or hypopnea.

26. The apparatus of claim 25 in which said template is one of a square wave and a shark-fin wave.

27. The apparatus of claim 25 in which said template has a maximum allowable swing between said first treatment pressure and said second treatment pressure.

28. The apparatus of claim 25 wherein the first treatment pressure is decreased in the absence of an indication of apnea, hypopnea and snoring.

29. A apparatus in accordance with claim 25 wherein the second treatment pressure is decreased in the absence of any indication of flow flattening and snoring.

30. The apparatus of claim 25 wherein said pressure-time template is stored in look-up tables or arrays.

31. A method for treating sleep disordered breathing with a ventilatory device;

said device including a controller, a blower, a patient interface, and a flow sensor;

comprising the steps of;

sensing leaks from the patient interface, the flow of air to the patient through the patient interface, and transitions between inspiration and expiration of the patient'"'"'s breathing cycle with said flow sensor;

detecting the pressure in the patient interface with said controller,

determining with said controller the presence of a first event and a second event based upon detected information, the first and second events being different indications of sleep disordered breathing; and

setting with said controller a first pressure as a function of the occurrence of the first event and adjusted for any leak, and setting a second pressure as a function of the occurrence of the second event and adjusted for any leak, the first pressure being used to determine the treatment pressure provided during the expiratory phase of the patient'"'"'s breathing cycle and the second pressure being used to determine the treatment pressure provided during the inspiratory phase of the patient'"'"'s breathing cycle.

32. The method of claim 31 wherein said first event indicative of the presence of sleep disordered breathing is one or more of apnea, hypopnea and snoring.

33. The method of claim 31 wherein said second event indicative of the presence of sleep disordered breathing is a flow limitation.

34. The method of claim 31 wherein said first pressure is an EPAP or EEP pressure.

35. The method of claim 31 wherein said second pressure is an IPAP pressure.

36. The method of claim 31 wherein said second pressure is greater than or equal to the first pressure.

37. The method of claim 36 wherein there is a predetermined maximum pressure difference between said first pressure and said second pressure.

38. The method of claim 36 wherein said first pressure and said second pressure have a maximum value of about 25 cm H2O.

39. The method of claim 31 wherein said first pressure has a minimum value of about 4 cm H2O.

40. The method of claim 31 wherein said controller causes said blower to provide the supply of air at positive pressure in accordance with a pressure-time template.

41. The method of claim 40 wherein said pressure-time template is a square wave.

42. The method of claim 40 wherein said pressure-time template is a shark-fin wave.

43. The method of claim 40 wherein said pressure-time template is stored in look-up tables or arrays.

44. The method of claim 31 wherein said controller further causes the blower to decrease the first pressure in the absence of the detection of first events.

45. The method of claim 31 wherein said controller further causes the blower to decrease the second pressure in the absence of the detection of second events.

46. An apparatus adapted for treatment of sleep disordered breathing comprising:

a blower for providing to a patient a supply of air at a treatment pressure in phase with the patient'"'"'s respiratory breathing cycle, the respiratory breathing cycle including an expiratory phase and an inspiratory phase;

a patient interface,

an air delivery conduit for delivering air from the blower to the patient interface, and

a controller for detecting the pressure in the patient interface, leaks from the patient interface, the flow of air to the patient through the patient interface, and transitions between inspiration and expiration of the patient'"'"'s breathing cycle;

said controller further determining the presence of a first event and a second event based upon detected information, the first and second events being different indications of sleep disordered breathing; and

setting a first pressure as a function of the occurrence of the first event and adjusted for any leak, and setting a second pressure as a function of the occurrence of the second event and adjusted for any leak, the first pressure being used to determine the treatment pressure provided during the expiratory phase of the patient'"'"'s breathing cycle and the second pressure being used to determine the treatment pressure provided during the inspiratory phase of the patient'"'"'s breathing cycle.

47. The apparatus of claim 46 wherein the first event indicative of the presence of sleep disordered breathing is one or more of apnea, hypopnea and snoring.

48. The apparatus of claim 46 wherein the second event indicative of the presence of sleep disordered breathing is flow limitation.

49. The apparatus of claim 46 wherein the first pressure is an EPAP or EEP pressure.

50. The apparatus of claim 46 wherein the second pressure is an IPAP pressure.

51. The apparatus of claim 46 wherein the second pressure is greater than or equal to the first pressure.

52. The apparatus of claim 51 wherein there is a predetermined maximum pressure difference between the first pressure and the second pressure.

53. The apparatus of claim 51 wherein the first pressure and the second pressure have a maximum value of about 25 cm H2O.

54. The apparatus of claim 46 wherein the first pressure has a minimum value of about 4 cm H2O.

55. The apparatus of claim 46 wherein the controller causes the blower to provide the supply of air at positive pressure in accordance with a pressure-time template.

56. The apparatus of claim 55 wherein the pressure-time template is a square wave.

57. The apparatus of claim 55 wherein the pressure-time template is a shark-fin wave.

58. The apparatus of claim 55 wherein the pressure-time template is stored in look-up tables or arrays.

59. The apparatus of claim 46 wherein the controller further causes the blower to decrease the first pressure in the absence of the detection of first events.

60. The apparatus of claim 46 wherein the controller further causes the blower to decrease the second pressure in the absence of the detection of second events.