System and Method for Improved Treatment of Sleeping Disorders using Therapeutic Positive Airway Pressure

• US 20120000466A1
• Filed: 09/14/2011
• Published: 01/05/2012
• Est. Priority Date: 06/18/2003
• Status: Abandoned Application

• Current Assignee: New York University
• Original Assignee: New York University
• Inventors: Rapoport, David M.
• Application Number:
  US13/232,673
• Publication Number:
  US 20120000466A1
• Time in Patent Office: Days
• US Class Current: 128/204.23
• 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 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit

Abstract

Described is a method and system providing therapeutic positive airway pressure to a particular area of patient'"'"'s airways. The system may include a flow generator and a processing arrangement. The flow generator supplies an airflow to an airway of the patient. The processing arrangement is connected to the flow generator to control a supply pressure at which the airflow is generated by the flow generator. The processing arrangement continuously adjusts the supply pressure to maintain a pressure in a predetermined portion of the patient'"'"'s airway substantially constant. The predetermined portion of the patient'"'"'s airway includes a collapsible portion of an upper airway of the patient. The processing arrangement also controls the supply pressure to maintain the pressure in the collapsible portion of the patient'"'"'s airway at a value at least as great as a tissue pressure below which the collapsible portion collapses.

Claims

1-22. -22. (canceled)

23. A device for treatment of a sleeping disorder, comprising:

a flow generator configured to supply air to an airway of a patient at a predetermined pressure P_A;

a processing arrangement operably connected to the flow generator to maintain a gas pressure within a predetermined portion of the patient'"'"'s airway within a desired range by adjusting one or both of the rate of airflow and a pressure supplied by the flow generator.

24. The device of claim 23, wherein the processing arrangement is configured to maintain a substantially constant pressure C_P within the patient'"'"'s airway, the pressure C_P being selected to prevent a collapse of the patient'"'"'s airway.

25. The device of claim 24, further comprising a mask connected to the tube and configured to connect the flow generator to the airway of the patient.

26. The device of claim 25, further comprising a flow tube extending from the flow generator to the airway of the patient, the flow tube having a resistance R_AB, wherein the value R_AB is measured when the flow generator is providing the airflow and the mask is open to the atmosphere.

27. The device of claim 26, wherein the flow generator is configured to provide the airflow at one of a constant and a variable flow rate.

28. The device of claim 26, wherein the pressure P_A may be continuously adjusted according to the formula:

P_A=C_P+R_AB*F_S+R_BC*Fp, wherein;

R_BC is a resistance in the predetermined portion of the patient'"'"'s airway;

F_s is an instantaneous rate of flow of air flowing from the flow generator to the patient;

F_p is an instantaneous rate of flow of air via inhalation and exhalation of the patient;

wherein the values of F_S and F_P are negative during expiration and positive during inspiration.

29. The device of claim 26, wherein the pressure P_A is continuously adjusted according to R_AB and R_BC, wherein R_BC is a resistance in the predetermined portion of the patient'"'"'s airway.

30. The device of claim 28, wherein the value of R_BC may be determined from one of (a) a resistance measured from the patient, (b) a fixed standardized resistance, (c) a resistance based on a rhinometric analysis of the patient and (d) an estimated resistance based on a pathology of the patient'"'"'s nose.

31. The device of claim 29, wherein the value of R_BC may be determined from one of (a) a resistance measured from the patient, (b) a fixed standardized resistance, (c) a resistance based on a rhinometric analysis of the patient and (d) an estimated resistance based on a pathology of the patient'"'"'s nose.

32. The device of claim 24, wherein the pressure C_P is maintained substantially constant throughout one of an entire inspiratory phase and a full respiratory cycle.

33. The device of claim 32, wherein the pressure C_P applied during the expiratory phase is lower than the pressure C_P applied during the inspiratory phase.

34. The device of claim 23, further comprising a venting arrangement configured to prevent the patient from rebreathing exhaled gases.

35. The device of claim 34, wherein the venting arrangement is one of a leak port or a non-rebreathing valve.

36. The device of claim 34, wherein the venting arrangement vents the exhaled gas to the atmosphere.

37. The device of claim 28, further comprising a first pressure sensor coupled to the flow tube and configured to measure a pressure within the flow tube and provide the measured data to the processing arrangement.

38. The device of claim 37, further comprising a second pressure sensor configured to measure a pressure in one of the mask and the flow generator and provide the measured data to the processing arrangement.

39. The device of claim 23, wherein the predetermined portion of the patient'"'"'s airway is a portion of the upper airway susceptible to collapse.

40. A method for treating a sleeping disorder, comprising the steps of:

supplying an airflow to an airway of a patient at a predetermined pressure P_A; and

maintaining a gas pressure within a predetermined portion of the patient'"'"'s airway within a desired range by adjusting one or both of the rate of airflow and a pressure supplied by the flow generator via a processing arrangement operably connected to a flow generator.

41. The method according to claim 40, wherein the processing arrangement is configured to maintain a substantially constant pressure C_P within the patient'"'"'s airway, the pressure C_P being selected to prevent a collapse of the patient'"'"'s airway.

42. The method according to claim 41, wherein the pressure C_P is maintained substantially constant in the predetermined portion throughout one of an entire inspiratory phase and a full respiratory cycle.

43. The method according to claim 41, further comprising the steps of:

generating the airflow using the flow generator, the flow generator being coupled to the patient'"'"'s airway by a flow tube; and

providing the airflow to a mask situated over at least one of a nose and a mouth of the patient via the flow tube.

44. The method according to claim 40, further comprising the step of:

diverting, via a venting arrangement, gases exhaled by the patient from an incoming airflow to prevent re-breathing of the exhaled gases.

45. The method according to claim 43, further comprising the step of:

determining a supply pressure P_A according to the following formula;

P_A=C_P+R_AB*Fs+R_BC*F_P

wherein,

P_A is the supply pressure provided by the flow generator;

R_AB is a resistance in the flow tube, wherein the value R_AB is measured when the flow generator is providing the airflow and the mask is opened to the atmosphere;

F_s is an instantaneous rate of flow of air flowing from the flow generator to the patient;

R_BC is a resistance in the predetermined portion of the patient'"'"'s airway, wherein the value of R_BC may be determined from one of (a) a resistance measured from the patient, (b) a fixed standardized resistance, (c) a resistance based on a rhinometric analysis of the patient and (d) an estimated resistance based on a pathology of the patient'"'"'s nose; and

F_P is an instantaneous rate of flow of air via inhalation and exhalation of the patient,

wherein the values of F_S and F_P are negative during expiration and positive during inspiration.

46. The method according to claim 45, further comprising the steps of:

measuring, via a first sensor, a first value of pressure in the flow tube; and

providing the measured data to the processing arrangement.

47. The method according to claim 46, further comprising the steps of:

measuring, via a second sensor, a second value of pressure within one of the flow generator and the mask; and

providing the measured data to the processing arrangement.