Method and apparatus for delivery of inhaled nitric oxide to spontaneous-breathing and mechanically-ventilated patients

• US 20030131848A1
• Filed: 01/21/2003
• Published: 07/17/2003
• Est. Priority Date: 11/24/1999
• Status: Active Grant

• Current Assignee: Advanced Inhalation Therapies (AIT) Ltd
• Original Assignee: Alex Stenzler
• Inventors: Stenzler, Alex
• Granted Patent: US 6,786,217 B2
• Time in Patent Office: Days
• US Class Current: 128/204.18
• CPC Class Codes: A61M 16/0833 T- or Y-type connectors, e.g. Y-piece
• CPC Class Codes: A61M 16/1015 using a gas flush valve, e.g. oxygen flush valve
• CPC Class Codes: A61M 16/12 by mixing different gases
• CPC Class Codes: A61M 16/203 Proportional
• CPC Class Codes: A61M 16/204 used for inhalation control
• CPC Class Codes: A61M 2016/102 Measuring a parameter of the content of the delivered gas
• CPC Class Codes: A61M 2016/1025 the O2 concentration
• CPC Class Codes: A61M 2202/0275 Nitric oxide [NO]

Abstract

A device-and method is disclosed for delivering NO to a patient. The device utilizes a single controller that controls two separate flow controllers to deliver an oxygen-containing gas and a NO-containing gas to the patient. The flow profiles of the oxygen-containing gas and the NO-containing gas are controlled by the controller. In one aspect of the invention, the flow profile of the NO-containing gas is proportional to the flow profile of the oxygen-containing gas throughout patient inspiration. In this regard, the patient receives a steady concentration of NO. In another aspect of the invention, the flow profile of the NO-containing gas is quasi-proportional to the flow profile of the oxygen-containing gas. In this regard, the NO-containing gas flow profile is altered to provide an increased concentration of NO either at the beginning or end of inspiration. In one aspect, the delivery device is used with mechanically-ventilated patients. In the other aspect of the delivery device, the device is used with spontaneously-breathing patients. The device and method, in a preferred embodiment, further contemplates using a gas purge or air flush feature to remove enriched-oxygen and/or NO from the device.

Claims

1. A method of delivering a steady concentration of nitric oxide to a spontaneously breathing patient via delivery means comprising the steps of:

detecting the onset of inspiration;

determining the inspiration flow profile for an individual breath;

supplying an oxygen-containing gas to the delivery means,,the oxygen-containing gas having a flow profile that tracks the inspiration flow profile; and

supplying an nitric oxide-containing gas to the delivery means, the nitric oxide-containing gas having a flow profile that is proportionally less than the flow profile of the oxygen-containing gas throughout inspiration.

2. A method according to claim 1, wherein the method further includes the step of monitoring the concentration of one or more of the following gases prior to the delivery means:

oxygen, nitric oxide, and nitrogen dioxide.

3. A method according to claim 1, wherein the flow profile of the nitric oxide-containing gas reaches zero flow at a time near the end of the patient inspiration flow profile, and wherein when said flow reaches zero, the flow profile of the oxygen-containing gas is greater than zero such that the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

4. A method according to claim 1, wherein the flow profile of the nitric oxide-containing gas is zero flow at the beginning of the patient inspiration flow profile, and wherein when said flow is zero, the flow profile of the oxygen-containing gas is greater than zero such that the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

5. A method according to claim 1, wherein the flow profile of the nitric oxide-containing gas is zero at the beginning of the patient inspiration profile while the flow profile of the oxygen-containing gas is greater than zero, and wherein at a time near the end of the patient inspiration flow profile, the flow profile of the nitric oxide-containing gas is zero while the flow profile of the oxygen-containing gas is greater than zero, wherein when the nitric oxide-containing gas flow reaches zero and the flow profile of the oxygen-containing gas is greater than zero the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

6. A method according to claim 1, further comprising the step of truncating the flow profile of the nitric oxide-containing gas to zero near the end of patient inspiration.

7. A method according to claim 1, wherein the delivery means is a nasal cannula.

8. A method according to claim 1, wherein the delivery means is a face mask.

9. A method according to claim 1, wherein the delivery means is a transtracheal catheter.

52. A method according to claim 1, wherein the delivery means is an endotracheal tube.

10. A method of delivering a non-constant concentration of nitric oxide to a spontaneously breathing patient via delivery means comprising the steps of:

detecting the onset of inspiration;

determining the inspiration flow profile for an individual breath;

supplying an oxygen-containing gas to the delivery means, the oxygen-containing gas having a flow profile that tracks the inspiration flow profile; and

supplying an nitric oxide-containing gas to the delivery means, the nitric oxide-containing gas having a flow profile that is less than, but closely tracks the oxygen-containing gas flow profile at the beginning of inspiration, wherein the difference between the flow profile of the oxygen-containing gas and the flow profile of the nitric oxide-containing gas progressively increases through the remainder of inspiration.

11. A method according to claim 10, further including the step of monitoring the concentration of one or more of the following gases prior to the delivery means:

oxygen, nitric oxide, and nitrogen dioxide.

12. A method according to claim 10, wherein the flow profile of the nitric oxide-containing gas reaches zero flow at a time near the end of the patient inspiration flow profile, and wherein when said flow reaches zero, the flow profile of the oxygen-containing gas is greater than zero such that the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

13. A method according to claim 10, wherein the delivery means is a nasal cannula.

14. A method according to claim 10, wherein the delivery means is a face mask.

15. A method according to claim 10, wherein the delivery means is a transtracheal catheter.

53. A method according to claim 10, wherein the delivery means is an endotracheal tube.

16. A method of delivering a non-constant concentration of nitric oxide to a spontaneously breathing patient comprising the steps of:

detecting the onset of inspiration;

determining the inspiration flow profile for an individual breath;

supplying an oxygen-containing gas to the delivery means, the oxygen-containing gas having a flow profile that tracks the inspiration flow profile; and

supplying an nitric oxide-containing gas to the delivery means, the nitric oxide-containing gas having a flow profile that is substantially less than the oxygen-containing gas flow profile at the beginning of inspiration compared to the end of inspiration, and wherein the difference between the flow profile of the oxygen-containing gas and the flow profile of the nitric oxide-containing gas progressively decreases throughout the remainder of inspiration.

17. A method according to claim 16, wherein the method further includes the step of monitoring the concentration of one or more of the following gases prior to the delivery means:

oxygen, nitric oxide, and nitrogen dioxide.

18. A method according to claim 16, wherein the flow profile of the nitric oxide-containing gas is zero at the beginning of inspiration and the flow profile of the oxygen-containing gas is positive.

19. A method according to claim 16, wherein the delivery means is a nasal cannula.

20. A method according to claim 16, wherein the delivery means is a face mask.

21. A method according to claim 16, wherein the delivery means is a transtracheal catheter.

54. A method according to claim 16, wherein the delivery means is an endotracheal tube.

22. A device for delivering nitric oxide to a spontaneous-breathing patient comprising:

a source of an oxygen-containing gas connected via tubing to a patient inspiration interface device;

a source of an nitric oxide-containing gas connected via tubing to the patient inspiration interface device;

a first proportional flow controller located between the source of oxygen-containing gas and the patient inspiration interface device for varying the flow rate of the oxygen-containing gas to the patient inspiration interface device;

a second proportional flow controller located between the source of nitric oxide-containing gas and the patient inspiration interface device for varying the flow rate of the nitric oxide-containing gas to the patient inspiration interface device;

an inspiration flow profile sensor that measures the inspiration flow profile of the inspiration breath of the patient; and

a controller for controlling the first and second proportional flow controllers in response to the inspiration flow profile from the inspiration flow profile sensor, the first and second proportional flow controllers being controlled such that the oxygen-containing gas has a flow profile that tracks the inspiration flow profile, and wherein the nitric oxide-containing gas has a flow profile that is proportionally less than the oxygen-containing gas throughout inspiration.

23. A device according to claim 22, the controller controlling the second proportional flow controller to stop the flow of the nitric oxide-containing gas at a time near the end of inspiration, and wherein the oxygen-containing gas continues to flow to purge the tubing and the patient inspiration interface device of nitric oxide.

24. A device according to claim 23, the device further including an input device to input gas purge parameters to the controller to truncate the flow profile of the nitric oxide-containing gas.

25. A device according to claim 22, the device further including at least one sensor located prior to the patient inspiration interface device for measuring the concentration of one or more of the following gases:

oxygen, nitric oxide, and nitrogen dioxide.

26. A device according to claim 22, wherein the patient inspiration interface device is a face mask.

27. A device according to claim 22, wherein the patient inspiration interface device is a nasal cannula.

28. A device according to claim 22, wherein the patient-inspiration interface device is a transtracheal catheter.

29. A device according to claim 22, further including an input device that inputs a proportionality set-point to control the degree of proportionality between the oxygen-containing gas and the nitric oxide-containing gas.

30. The device according to claim 22, wherein the source of the oxygen-containing gas is a pressurized cylinder.

31. The device according to claim 22, wherein the source of the oxygen-containing gas is a wall gas supply.

32. The device according to claim 22, wherein the source of the oxygen-containing gas is an air compressor.

33. A method of delivering a constant concentration of nitric oxide to a mechanically-ventilated patient via single controller, the mechanical ventilator having an inspiration limb and an expiration limb, the method comprising the steps of:

setting the desired inspiration flow profile in the controller;

varying the flow rate of an oxygen-containing gas in accordance with the inspiration flow profile by delivering a first signal from said controller to a first control valve controlling the rate of flow of an oxygen-containing gas to the patient, thereby creating a flow profile of oxygen-containing gas; and

varying the flow rate of a nitric oxide-containing gas in accordance with the inspiration profile by delivering a second signal from said controller to a second control valve controlling the rate of flow of the nitric oxide-containing gas to the patient, creating a flow profile of nitric oxide-containing gas, said flow profile being less than and proportional to the flow profile of the oxygen-containing gas throughout patient inspiration.

34. A method according to claim 33, wherein the flow profile of the nitric oxide-containing gas reaches zero flow at a time near the end of the patient inspiration flow profile, and wherein the flow profile of the oxygen-containing gas is greater than zero such that the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

35. A method according to claim 33, wherein the flow profile of the nitric oxide-containing gas is zero flow at the beginning of the patient inspiration flow profile, and wherein when said flow is zero, the flow profile of the oxygen-containing gas is greater than zero such that the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

36. A method according to claim 33, wherein the flow profile of the nitric oxide-containing gas is zero at the beginning of the patient inspiration profile while the flow profile of the oxygen-containing gas is greater than zero, and wherein at a time near the end of the patient inspiration flow profile the flow profile of the nitric oxide-containing gas is zero while the flow profile of the oxygen-containing gas is greater than zero, wherein when the nitric oxide-containing gas flow reaches zero and the flow profile of the oxygen-containing gas is greater than zero the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

37. A method according to claim 33, further including the step of monitoring the concentration of one or more of the following gases in the inspiration limb:

oxygen, nitric oxide, and nitrogen dioxide.

38. A method according to claim 33, further comprising the step of truncating the flow profile of the nitric oxide-containing gas to zero near the end of patient inspiration.

39. A method of delivering a non-constant concentration of nitric oxide to a mechanically-ventilated patient via single controller, the mechanical ventilator having an inspiration limb and an expiration limb, the method comprising the steps of:

setting the desired inspiration flow profile in the controller;

varying the flow rate of an oxygen-containing gas in accordance with the inspiration flow profile by delivering a first signal from said controller to a first control valve controlling the rate of flow of an oxygen-containing gas to the patient, thereby creating a flow profile of oxygen-containing gas; and

varying the flow rate of a nitric oxide-containing gas in accordance with the inspiration profile by delivering a second signal from said controller to a second control valve controlling the rate of flow of the nitric oxide-containing gas to the patient, creating a flow profile of nitric oxide-containing gas that is less than, but closely tracks the oxygen-containing gas flow profile in the beginning of the inspiration, wherein the difference between the flow profiles of the oxygen-containing gas and the nitric oxide-containing gas progressively increases through the remainder of inspiration.

40. A method according to claim 39, wherein the flow profile of the nitric oxide-containing gas reaches zero flow at a time near the end of the patient inspiration flow profile, and wherein when said flow reaches zero, the flow profile of the oxygen-containing gas is greater than zero such that the oxygen-containing gas purges the inspiration limb of nitric oxide-containing gas.

41. A method according to claim 39, further including the step of monitoring the concentration of one or more of the following gases in the inspiration limb:

oxygen, nitric oxide, and nitrogen dioxide.

42. A method of delivering a non-constant concentration of nitric oxide to a mechanically-ventilated patient via single controller, the mechanical ventilator having an inspiration limb and an expiration limb, the method comprising the steps of:

setting the desired inspiration flow profile in the controller;

varying the flow rate of an oxygen-containing gas in accordance with the inspiration flow profile by delivering a first signal from said controller to a first control valve controlling the rate of flow of an oxygen-containing gas to the patient, thereby creating a flow profile of oxygen-containing gas; and

varying the flow rate of a nitric oxide-containing gas in accordance with the inspiration profile by delivering a second signal from said controller to a second control valve controlling the rate of flow of the nitric oxide-containing gas to the patient, the nitric oxide-containing gas having a flow profile that is substantially less than the oxygen-containing gas flow profile at the beginning of inspiration, and wherein the difference between the flow profile of the oxygen-containing gas and the nitric oxide-containing gas progressively decreases throughout the remainder of inspiration.

43. A method according to claim 42, wherein the flow profile of the nitric oxide-containing gas is zero at the beginning of inspiration and the flow profile of the oxygen-containing gas is positive.

44. A method according to claim 42, further including the step of monitoring the concentration of one or more of the following gases in the inspiration limb:

oxygen, nitric oxide, and nitrogen dioxide.

45. A device for delivering nitric oxide to a patient that is mechanically-ventilated comprising;

a source of an oxygen-containing gas connected to a patient inspiration limb;

a source of a nitric oxide-containing gas connected to the patient inspiration limb;

a first proportional flow control valve located between the source of oxygen-containing gas and the patient for varying the flow rate of the oxygen-containing gas to the patient;

a second proportional flow controller located between the source of nitric oxide-containing gas and the patient for varying the flow rate of the nitric oxide-containing gas to the patient;

a controller including instructions for the inspiration flow profile, the controller further controlling the first and second proportional flow controllers in response to the inspiration flow profile, the first and second proportional flow controllers being controlled such that the oxygen-containing gas has a flow profile that tracks the inspiration flow profile, and wherein the nitric oxide-containing gas has a flow profile that is proportionally less than the oxygen-containing gas throughout inspiration.

48. A device according to claim 45, the controller containing instructions for truncating the flow profile of the nitric oxide-containing gas to zero near the end of patient inspiration.

46. A device for delivering nitric oxide to a patient that is mechanically-ventilated comprising;

a source of an oxygen-containing gas connected to a patient inspiration limb;

a source of a nitric oxide-containing gas connected to the patient inspiration limb;

a first proportional flow control valve located between the source of oxygen-containing gas and the patient for varying the flow rate of the oxygen-containing gas to the patient;

a second proportional flow controller located between the source of nitric oxide-containing gas and the patient for varying the flow rate of the nitric oxide-containing gas to the patient;

a controller including instructions for the inspiration flow profile, the controller further controlling the first and second proportional flow controllers in response to the inspiration flow profile, the first and second proportional flow controllers being controlled such that the oxygen-containing gas has a flow profile that tracks the inspiration flow profile, and wherein the nitric oxide-containing gas flow profile is less than, but closely tracks the oxygen-containing gas flow profile in the beginning of the inspiration, wherein the difference between the flow profiles of the oxygen-containing gas and the nitric oxide-containing gas progressively increases through the remainder of inspiration.

47. A device for delivering nitric oxide to a patient that is mechanically-ventilated comprising;

a source of an oxygen-containing gas connected to a patient inspiration limb;

a source of a nitric oxide-containing gas connected to the patient inspiration limb;

a first proportional flow control valve located between the source of oxygen-containing gas and the patient for varying the flow rate of the oxygen-containing gas to the patient;

a second proportional flow controller located between the source of nitric oxide-containing gas and the patient for varying the flow rate of the nitric oxide-containing gas to the patient;

a controller including instructions for the inspiration flow profile, the controller further controlling the first and second proportional flow controllers in-response to the inspiration flow profile, the first and second proportional flow controllers being controlled such that the oxygen-containing gas has a flow profile that tracks the inspiration flow profile, and wherein the nitric oxide-containing gas flow profile having a flow profile that is substantially less than the oxygen-containing gas flow profile at the beginning of inspiration, and wherein the difference between the flow profile of the oxygen-containing gas and the nitric oxide-containing gas progressively decreases throughout the remainder of inspiration.

49. A device for delivering nitric oxide to a spontaneous-breathing patient comprising:

a source of an oxygen-containing gas connected via tubing to a patient inspiration interface device;

a source of an nitric oxide-containing gas connected via tubing to the patient inspiration interface device;

a first proportional flow controller located between the source of oxygen-containing gas and the patient inspiration interface device for varying the flow rate of the oxygen-containing gas to the patient inspiration interface device;

a second proportional flow controller located between the source of nitric oxide-containing gas and the patient inspiration interface device for varying the flow rate of the nitric oxide-containing gas to the patient inspiration interface device;

an inspiration flow profile sensor that measures the inspiration flow profile of the inspiration breath of the patient; and

a controller for controlling the first and second proportional flow controllers in response to the inspiration flow profile from the inspiration flow profile sensor, the first and second proportional flow controllers being controlled such that the oxygen-containing gas has a flow profile that tracks the inspiration flow profile, and wherein the nitric oxide-containing gas flow profile having a flow profile that is substantially less than the oxygen-containing gas flow profile at the beginning of inspiration, and wherein the difference between the flow profile of the oxygen-containing gas and the nitric oxide-containing gas progressively decreases throughout the remainder of inspiration.

50. A device for delivering nitric oxide to a spontaneous-breathing patient comprising:

a source of an oxygen-containing gas connected via tubing to a patient inspiration interface device;

a source of an nitric oxide-containing gas connected via tubing to the patient inspiration interface device;

1

a first proportional flow controller located between the source of oxygen-containing gas and the patient inspiration interface device for varying the flow rate of the oxygen-containing gas to the patient inspiration interface device;

a second proportional flow controller located between the source of nitric oxide-containing gas and the patient inspiration interface device for varying the flow rate of the nitric oxide-containing gas to the patient inspiration interface device;

an inspiration flow profile sensor that measures the inspiration flow profile of the inspiration breath of the patient; and

a controller for controlling the first and second proportional flow controllers in response to the inspiration flow profile from the inspiration flow profile sensor, the first and second proportional flow controllers being controlled such that the oxygen-containing gas has a flow profile that tracks the inspiration flow profile, and wherein the nitric oxide-containing gas flow profile having a flow profile that is substantially less than the oxygen-containing gas flow profile at the beginning of inspiration, and wherein the difference between the flow profile of the oxygen-containing gas and the nitric oxide-containing gas progressively decreases throughout the remainder of inspiration.

51. A method of delivering nitric oxide via delivery means to a mechanically or spontaneously breathing patient having a certain inspiration profile comprising the steps of:

supplying in a first breath a mixture of oxygen-containing gas and a nitric oxide-containing gas to the delivery means, the oxygen-containing gas and a nitric oxide-containing gas having a flow profile proportional or quasi proportional to the inspiration flow profile;

supplying in at least one next breath, a source of enriched oxygen-containing gas having a flow profile that is proportional or quasi-proportional to the inspiration flow profile; and

supplying a source of air at or near the end of the first and next breaths to flush the delivery means of enriched oxygen and nitric oxide.

55. A method of delivering nitric oxide to a spontaneously breathing patient via delivery means comprising the steps of:

detecting the onset of inspiration;

supplying an oxygen-containing gas to the delivery means, the oxygen-containing gas having a pre-programmed flow profile; and

supplying an nitric oxide-containing gas to the delivery means, the nitric oxide-containing gas having a pre-programmed flow profile that is proportional or quasi-proportional to the flow-profile of the oxygen-containing gas throughout inspiration.

56. A device for delivering nitric oxide to a spontaneous-breathing patient comprising:

a source of an oxygen-containing gas connected via tubing to a patient inspiration interface device;

a source of an nitric oxide-containing gas connected via tubing to the patient inspiration interface device;

a first proportional flow controller located between the source of oxygen-containing gas and the patient inspiration interface device for varying the flow rate of the oxygen-containing gas to the patient inspiration interface device;

a second proportional flow controller located between the source of nitric oxide-containing gas and the patient inspiration interface device for varying the flow rate of the nitric oxide-containing gas to the patient inspiration interface device;

an inspiration flow profile sensor that detects the onset of inspiration of the patient; and

a controller for controlling the first and second proportional flow controllers in response to the detection of the onset of inspiration from the inspiration flow profile sensor, the first and second proportional flow controllers being controlled such that the nitric oxide-containing gas has pre-programmed flow profile that is proportional or quasi-proportional to the flow profile of the oxygen-containing gas throughout inspiration.