Methods, systems and devices for non-invasive ventilation including a non-sealing ventilation interface with a free space nozzle feature
09962512 ยท 2018-05-08
Assignee
Inventors
- Joseph Cipollone (San Ramon, CA)
- Joey Aguirre (San Ramon, CA)
- Todd Allum (Livermore, CA)
- Darius Eghbal (Oakland, CA)
- Anthony D. Wondka (Thousand Oaks, CA)
Cpc classification
A61M2016/0021
HUMAN NECESSITIES
A61M2016/0024
HUMAN NECESSITIES
A61M16/208
HUMAN NECESSITIES
International classification
A61M16/00
HUMAN NECESSITIES
Abstract
A system for supplying ventilatory support may include a nasal interface configured to communicate with a patient's nose while allowing the patient to breathe ambient air directly without flowing through the nasal interface. A nozzle may be associated with the nasal interface at a distance from a nose. The nozzle may be connectable to the gas delivery circuit and the gas delivery source. The nozzle may be capable of delivering gas into the nasal passage by creating negative pressure area near the nozzle and a positive pressure area near the entrance to the nose. A combination of gas from the gas delivery source and air entrained from the gas exiting the nozzle may provide ventilatory support.
Claims
1. A system for supplying ventilatory support, comprising: a gas delivery source; a gas delivery circuit; a non-sealing nasal interface configured to be placed under a nose of a patient and to communicate with the patient's nostril airway while allowing the patient to breathe ambient air; a nozzle associated with the non-sealing nasal interface and configured to be positioned a distance from a nostril entrance of the patient's nostril airway when the non-sealing nasal interface is placed under the nose of the patient, the nozzle being connectable to the gas delivery circuit and the gas delivery source; wherein the nozzle is configured to deliver a gas flow cone defined by the gas exiting the nozzle, such that when the non-sealing nasal interface is placed under the nose of the patient, the gas flow cone intersects with an internal wall of the patient's nostril airway at an intersecting point, the area inside the gas flow cone and the area within the patient's nostril airway distal to the intersecting point defining a positive pressure area wherein a laminar positive pressure flow is developed, the area outside the gas flow cone defining a negative pressure area entraining ambient air into the patient's nostril airway; and wherein a combination of gas from the gas delivery source and air entrained into the patient's nostril airway provide ventilatory support.
2. The system of claim 1, wherein the non-sealing nasal interface comprises a manifold, and wherein the manifold comprises the nozzle.
3. The system of claim 2, wherein the manifold is configured to position the nozzle at the distance away from the nostril entrance, and configured to position the nozzle at an angle relative a centerline of the nostril airway.
4. The system of claim 1, further comprising one or more sensors.
5. The system of claim 4, wherein the one or more sensors comprise a sensing channel that extends away from the nozzle toward the nose terminating in the positive pressure area.
6. The system of claim 4, wherein the one or more sensors comprise a sensing channel that extends distally away from the nozzle.
7. The system of claim 6, wherein the sensing channel extends into the nose of the patient.
8. The system of claim 6, wherein the sensing channel extends to within approximately +/5 mm from the nostril entrance.
9. The system of claim 1, further comprising two or more nozzles per nostril.
10. The system of claim 1, wherein the nozzle is an oval-shaped gas delivery nozzle orifice.
11. The system of claim 1, wherein the nozzle comprises an array of multiple gas delivery nozzles arranged in a circular or oval pattern.
12. The system of claim 1, further comprising a jet pump throat comprising a flow path.
13. The system of claim 12, wherein the jet pump throat is associated with a manifold, and the nozzle is associated with a jet pump throat flow path through the jet pump throat.
14. The system of claim 13, wherein the manifold comprises an entrainment port in communication with the jet pump throat flow path.
15. The system of claim 1, wherein the nozzle angles inward.
16. The system of claim 15, wherein the nozzle angles inward at an angle of 1 degree to 20 degrees.
17. The system of claim 1, wherein the nozzle creates an oval shaped gas flow cone within a nostril airway.
18. The system of claim 17, wherein the nozzle is rotatably adjustable.
19. The system of claim 1, wherein the nozzle comprises at least one left nozzle and at least one right nozzle, wherein the spacing between the at least one left nozzle and the at least one right nozzle is adjustable.
20. The system of claim 19, wherein the at least one left nozzle and the at least one right nozzle are rotatably adjustable.
21. The system of claim 1, wherein spacing between the nostril entrance and nozzle is adjustable.
22. The system of claim 1, wherein the non-sealing nasal interface is available in different sizes, differing in nozzle spacing, nozzle rotational orientation and nozzle distance to nostril entrance.
23. The system of claim 1, wherein a negative pressure of the negative pressure area is less than ambient.
24. The system of claim 23, wherein the negative pressure of the negative pressure area is 5 cmH.sub.2O to 28 cmH.sub.2O.
25. The system of claim 1, wherein the positive pressure of the positive pressure area is greater than ambient.
26. The system of claim 25, wherein the positive pressure of the positive pressure area is approximately 0.01 psi to approximately 0.50 psi.
27. The system of claim 1, wherein the nozzle is positioned at a distance of up to 1.5 inches from the nostril entrance of the patient's nostril airway when the non-sealing nasal interface is placed under the nose of the patient.
28. The system of claim 1, wherein delivery of gas through the nozzle is synchronized with a breathing pattern of the patient.
29. The system of claim 1, wherein the gas from the gas delivery source is controlled by a wearable ventilator.
30. The system of claim 1, wherein ventilatory support comprises reducing the work of breathing to treat respiratory insufficiency.
31. The system of claim 1, wherein ventilatory support comprises elevating airway pressure to treat sleep apnea.
32. The system of claim 1, wherein the non-sealing nasal interface comprises a connector for coupling the system to a bridge of the nose and aligning the nozzle with the nostril entrance of the patient's nostril airway.
33. The system of claim 32, wherein the aligning of the nozzle with the nostril entrance of the patient's nostril airway comprises adjusting the angle of the nozzle to be in alignment with the centerline of the nostril airway.
34. A method for providing portable non-invasive open-airway ventilatory support, the method comprising: providing a non-sealing nasal interface configured to be placed under a nose of a patient and to communicate with the patient's nostril airway while allowing the patient to breathe ambient air; and providing a nozzle associated with the non-sealing nasal interface and configured to be positioned a distance from a nostril entrance of the patient's nostril airway when the non-sealing nasal interface is placed under the nose of the patient, the nozzle being adapted to be in fluid communication with a gas delivery circuit and a gas delivery source; wherein the nozzle is of configured to deliver a gas flow cone defined by the gas exiting the nozzle, such that when the non-sealing nasal interface is placed under the nose of the patient, the gas flow cone intersects with an internal wall of the patient's nostril airway at an intersecting point, the area inside the gas flow cone and the area within the patient's nostril airway distal to the intersecting point defining a positive pressure area wherein a laminar positive pressure flow is developed, the area outside the gas flow cone defining a negative pressure area entraining ambient air into the patient's nostril airway; wherein a combination of gas from the gas delivery source and air entrained into the patient's nostril airway provides ventilatory support.
35. The method of claim 34, wherein the non-sealing nasal interface comprises a manifold, and wherein the manifold comprises the nozzle.
36. The method of claim 35, wherein the manifold is configured to position the nozzle at the distance away from the nostril entrance, and configured to position the nozzle at an angle relative a centerline of the nostril airway.
37. The method of claim 34, further comprising one or more sensors.
38. The method of claim 37, wherein the one or more sensors comprise a sensing channel that extends away from the nozzle toward the nose terminating in the positive pressure area.
39. The method of claim 37, wherein the one or more sensors comprise a sensing channel that extends distally away from the nozzle.
40. The method of claim 39, wherein the sensing channel extends into the nose of the patient.
41. The method of claim 39, wherein the sensing channel extends to within +/5 mm from the nostril entrance.
42. The method of claim 34, further comprising two or more nozzles per nostril.
43. The method of claim 34, wherein the nozzle is an oval-shaped gas delivery nozzle orifice.
44. The method of claim 34, wherein the nozzle comprises an array of multiple gas delivery nozzles arranged in a circular or oval pattern.
45. The method of claim 34, further comprising a jet pump throat comprising a flow path.
46. The method of claim 45, wherein the jet pump throat is associated with a manifold, and the nozzle is associated with a jet pump throat flow path through the jet pump throat.
47. The method of claim 46, wherein the manifold comprises an entrainment port in communication with the jet pump throat flow path.
48. The method of claim 34, wherein the nozzle angles inward.
49. The method of claim 48, wherein the nozzle angles inward at an angle of 1 degree to 20 degrees.
50. The method of claim 34, wherein the nozzle creates an oval shaped gas flow cone within the nostril airway.
51. The method of claim 50, wherein the nozzle is rotatably adjustable.
52. The method of claim 34, wherein the nozzle comprises at least one left nozzle and at least one right nozzle, wherein the spacing between the at least one left nozzle and the at least one right nozzle is adjustable.
53. The method of claim 52, wherein the at least one left nozzle and the at least one right nozzle are rotate-ably adjustable.
54. The method of claim 34, wherein spacing between the nostril entrance and nozzle is adjustable.
55. The method of claim 34, wherein the non-sealing nasal interface is available in different sizes, differing in nozzle spacing, nozzle rotational orientation and nozzle distance to nostril entrance.
56. The method of claim 34, wherein the negative pressure of the negative pressure area is less than ambient.
57. The method of claim 56, wherein the negative pressure of the negative pressure area is 5 cmH.sub.2O to 28 cmH.sub.2O.
58. The method of claim 34, wherein the positive pressure of the positive pressure area is greater than ambient.
59. The method of claim 58, wherein the positive pressure of the positive pressure area is 0.01 psi to 0.50 psi.
60. The method of claim 34, wherein the nozzle is positioned at a distance of up to 1.5 inches from the nostril entrance of the patient's nostril airway when the non-sealing nasal interface is placed under the nose of the patient.
61. The method of claim 34, wherein delivery of gas through the nozzle is synchronized with a breathing pattern of the patient.
62. The method of claim 34, wherein the gas from the gas delivery source is controlled by a wearable ventilator.
63. The method of claim 34, wherein ventilatory support comprises reducing the work of breathing to treat respiratory insufficiency.
64. The method of claim 34, wherein ventilatory support comprises elevating airway pressure to treat sleep apnea.
65. The method of claim 34, wherein the non-sealing nasal interface comprises a connector for coupling the system to a bridge of the nose and aligning the nozzle with the nostril entrance of the patient's nostril airway.
66. The method of claim 65, wherein the aligning of the nozzle with the nostril entrance of the patient's nostril airway comprises adjusting the angle of the nozzle to be in alignment with a centerline of the nostril airway.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and together with the detailed description serve to explain the principles of the invention.
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DETAILED DESCRIPTION OF THE EMBODIMENTS
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(58) A similar system to
(59) Embodiments of the present invention will now be described with reference to the remaining figures. Respiratory support or airway support is provided in a manner and way that the patient is unencumbered. The non-invasive, non-sealing and unobtrusive systems and methods may allow for mobility and activities of daily life. The systems and methods allow for the sensation of breathing from ambient surroundings normally. The systems and methods provide an easily portable system that can be readily borne or worn by the patient, and gas delivery tubing that does not encumber the patient.
(60) Systems and methods may include a gas delivery source, a gas delivery circuit, and a nasal interface that allow breathing ambient air through the nasal interface. A gas flow path through the nasal interface may have a distal gas flow path opening. A nozzle may be associated with a proximal end of the nasal interface a distance from the distal end gas flow path opening. In certain embodiments, at least a portion of an entrainment port may be between the nozzle and the distal end gas flow opening. The nozzle may deliver gas into the nasal interface to create a negative pressure area in the gas flow path at the entrainment port. The nasal interface and the nozzle may create a positive pressure area between the entrainment port and the distal end of the nasal interface. Gas from the gas delivery source and air entrained through the entrainment port may increase airway pressure.
(61)
(62) The present invention may include a non-sealing nasal mask patient interface, connected to the ventilator with small bore gas delivery tubing. The nasal mask may be uniquely non-sealing, so that the patient can inhale and exhale ambient air directly through the mask while receiving ventilatory support, in which there is negligible dead space volume in the mask. The mask may include a unique Venturi system that makes it possible for the ventilator to deliver relatively small amounts of gas to achieve relatively high levels of ventilatory support or airway pressure. The Venturi mask is described in more detail in
(63) Various embodiments of the nasal interface 303 are described in detail in the following disclosure. The nasal interface 303 may be minimally obtrusive compared to standard masks, so that the patient can feel and act normally while receiving the therapy. For example, the patient can talk, swallow, eat or drink, and feel like they are breathing normally, with the nasal interface and therapy. The gas delivery tubing required may be very small compared to standard ventilator tubing, which more readily allows the patient to move around with the system, and to conceal the equipment and tubing needed for the therapy. The efficiency of the Venturi system in achieving therapeutic levels of lung or airway pressure while using low levels of gas volume, allows the gas supply to be relatively small, further enabling mobility of the patient, and or miniaturization of the ventilation equipment. A nasal interface may be configured to communicate with a patient's nose while allowing the patient to breathe ambient air directly without flowing through the nasal interface.
(64) While
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(66) A ventilator module 401 may include or is in communication with several other functional accessories. The ventilator and the patient's internal anatomy from
(67) An oxygen source 407 and/or a compressed air source 409 can be included, typically external to the ventilator module 401. In certain embodiments, however, the oxygen source 407 and/or the compressed air source 409 can be internal to the ventilator module 401 if the therapy is being used for stationary use, for example, in the home. A blender 411 can be included to control the fractional delivered O2 in a gas delivery circuit 413. A pulse oximeter 415 can be used to titrate settings of the ventilator module 401 to meet the physiological needs of the patient, for example setting the correct oxygen blender setting or ventilator volume output. In addition to compressed supplies of oxygen and air gas, the ventilator module 401 can include internal or external air and oxygen generating systems 417, such as a compressor, pump or blower to create pressurized air, an oxygen generator and/or pump to create pressurized oxygen gas, and/or a compressed gas accumulator. The oxygen source can also be liquid oxygen, or a liquid oxygen generating system. An internal or external humidifier 405 can be included for extended uses of the therapy, or if using in dry climates.
(68) As the therapy is frequently used to help ADL's, and to promote activity, a pedometer 419 and/or actigraphy sensor 421 can be included internal to or external to a ventilator module 401. Optional sensors may include a CO.sub.2 sensor 425, and/or an external breathing sensor unit 437. A CO.sub.2 sensing line 439 and/or an airway pressure sensing line 441 may be present. One or more other external sensors may be included. For example, other external sensors may include an external respiration sensor or respiration effort sensor 427, such as a respiratory muscle effort sensor, a chest impedance sensor 435, or other types of sensors, such as a tracheal or other microphone or vibration sensor 443 or acoustical or ultrasonic sensor. The one or more external sensors may be used either as a redundant sensor to a nasal airflow or nasal pressure sensor 429, or to complement the information obtained from the nasal airflow or nasal pressure sensor 429, or in place of the nasal airflow or nasal pressure sensor 429. An oral airflow breathing sensor may also be used, for example nasal airflow or nasal pressure sensor 429 may alternatively be an oral airflow sensor.
(69) A drug delivery module 431 can be incorporated internally or externally to a ventilator module 401. Because of the challenges with current aerosolized drug delivery inhalers, the drug delivery module 431 can be used to propel and deposit medication particles deep in the respiratory system without a carrier propellant. Because the patient's using the therapy often may also require prescription medication, this may be a convenient and efficient way to administer the medication.
(70) When the therapy is being used for respiratory support, the user may have two options: (1) wearing or toting the ventilator module 401 so that the user can be ambulatory or enjoy the activities of daily living, or (2) stationary use, in the event the patient plans on being stationary or does not have the ability to ambulate. For the later, the delivery circuit can optionally be provided in a 25-100 foot length, such that the gas source and ventilator module 401 can be stationary in the patient's home, while the patient can move around their home while wearing the interface and receiving the therapy. Or, the gas source can be stationary, and connected to the ventilator module 401 with a 25-100 foot hose, so that the patient can wear or tote the ventilator and be mobile within the range of the hose.
(71) The ventilator module 401 may include one or more processors 445 and one or more memories 447 to analyze information and output therapies.
(72) Ventilation gas 449 may exit at a speed that entrains ambient air 451, such that the combination of ventilation gas 449, entrained ambient air 451 and spontaneously inhaled air, if the patient is spontaneously breathing, is delivered 453 to the patient's airways, such as the nasal cavity 455, oropharyngeal airway 457, trachea 459, lung 461 and others, under power to create a clinically efficacious effect on the lung and airways. Patient may exhale 463 through the nose or mouth. Various airways are also included, such as nostril airway 473, nasal airway 475, oral airway 481, upper airway 477, and lower airway 479.
(73) When using the invention, the patient breathes normally through their upper airway and through their nose, while receiving mechanical support through the interface. During exhalation, the exhaled gas preferably does not enter the gas delivery circuit but rather exits the nose or mouth directly to ambient air, or through, across or around the nasal interface 400 to ambient air. The patient can keep their mouth closed during use for example during inspiration, to help direct the mechanical support to the lower airways and past the oral cavity 465, base of the tongue 467, palate 469 and esophagus 471, or can use a mouth guard or chin band, if necessary. The patient may exhale through their mouth when using the therapy.
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(76) Gas delivery tubing 511 and pressure sensing tubing 515 from a ventilator, as shown in
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(78) In certain embodiments, a rotatable joint 517 between the gas delivery tubing 511 and manifold 503 and/or a rotatable joint 519 between the pressure sensing tube 515 and manifold 503, may include detent settings. These detent setting joints 517, 519 can be used to adjust the angle of the manifold 503 to adjust the angle of the gas delivery nozzles 507 to be in alignment with the patient's nostril airway. Alternatively, the gas delivery tubing 511 and pressure sensing tubing 515 can be connectable to the manifold 503 in different rotational orientations to likewise align the gas delivery nozzles 507 with the patient's nostril airway.
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(81) Distance from Nozzle to Nose:
(82) The gas delivery nozzle 713 may be integrated into a manifold 709, and the manifold 709 may be shaped, dimensioned and configured to position the gas delivery nozzle 713 at an ideal position under a nostril entrance 707. A distance of the gas delivery nozzle 713 to the nostril entrance 707 may be chosen to optimize the function of the Venturi created by the gas delivery nozzle 713 and the nares. Optimal function may be described as generating maximal pressure in the nostril airway 703 while the gas delivery is still comfortable and tolerable to the user.
(83) Typically, laminar positive pressure flow should be developed before the airflow reaches deep into the nostril. This positive pressure flow may be defined by the area inside and distal to the gas flow cone defined by the gas exiting the gas delivery nozzle 713. The area outside of this cone is negative pressure created by the Venturi, which entrains ambient air into the nose and nasal passage, thus generating the energy required for mechanical ventilatory support. When this cone intersects with the internal wall of the nostril, the distal side of that intersecting point is positive pressure.
(84) Alternatively, based on position of the gas delivery nozzle 713 and other operational parameters and device dimensions, this cone can be wider than the entrance to the nostril when it reaches the nostril. In this event, positive pressure occurs outside of the nostril and extends distally. Also alternatively, this cone can intersect with the nostril walls at a distance inside the nostril, thereby allowing a negative pressure zone to occur at the entrance to and slightly inside the nostril, but then transitioning to positive pressure distal to the intersecting point. Because the cross sectional geometry is non-uniform, for example, not a perfectly circular, there is variability with the gas flow cone intersecting points with the nostril wall, around the circumference of the cone and nostril. As will be described subsequently, specific embodiments of the nasal mask may address this nuance such that more uniform and predictable performance can be achieved.
(85) In the embodiment of
(86) Position of Breathing Pressure Sensing Port:
(87) For embodiments of the invention to be effective, it may be necessary to measure and monitor breathing of the patient to properly synchronize a ventilator gas delivery control system with spontaneous breathing patterns of the patient, as desired clinically. Therefore, while the gas delivery nozzles 713 may be positioned ideally at a distance away from the user's nostril entrance 707, breathing pressure sensing cannula 715, breathing pressure sensing ports or other sensors may need to be placed near, at or inside the nostril entrance 707. For example, the distal end of the pressure sensing cannula 715 can be placed slightly inside the nose in the area where positive pressure has been created by the Venturi system.
(88) It may be beneficial to have multiple locations for measuring pressure. For example, one location may be used for detecting and measuring the spontaneous breathing pressure of the patient, and a different location for measuring the pressure generated by the ventilation system. For example, a breathing pressure sensing port may be placed slightly inside the nostril entrance 707, and a ventilation gas pressure sensor may be placed outside the nostril entrance 707, or alternatively deeper inside the nostril airway 703.
(89) The location of pressure sensing ports, such as the breathing pressure sensing cannula 715, may be selected to optimize accuracy and fidelity. For example, a breathing pressure sensing port, such as the breathing pressure sensing cannula 715, may be arranged so that it is located near the medial aspect of the nostril airway 703, or at the posterior aspect of the nostril airway 703. Multiple breathing pressure sensing locations may also be used. For example, a sensing port at a medial posterior aspect of the nostril airway 703 may be used to measure inhalation pressures accurately, and a sensing port at the anterior aspect of the nostril airway 703 may be used to measure exhalation pressures accurately.
(90) In addition to a nostril airway breathing pressure sensor, other sensor types or locations may be used. For example, a microphone or ultrasonic sensor can be used to detect phases of breathing when placed on the user's neck to detect movements of air in the trachea. Other sensors and sensor locations can be used.
(91) In addition to the ventilation pressure being measured by a pressure sensing port outside of the nose, at the nostril entrance, or inside the nostril airway, the ventilation pressure can be derived by other apparatus and methods. For example, a gas delivery pressure in the gas delivery circuit can be correlated to a delivered ventilation pressure that is delivered to the patient by the ventilation system by measuring key relevant patient parameters, such as airway resistance and respiratory track compliance, and correlating those parameters with delivered pressure based on a gas delivery pressure.
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(94) Key dimensions and values of the ventilation nasal mask are indicated in Table 1. The parameters provided by the ventilation nasal mask and system are indicated in Table 2. Additional exemplary dimensions, values and materials of the ventilation nasal mask are indicated in Table 3.
(95) Nozzle Patterns:
(96) In certain situations, delivery of ventilation gas to the patient through one left and one right gas delivery nozzles may not develop the laminar flow desired due to the variability found in patient's nostril and nasal air passage geometries. Therefore, in certain embodiments of the invention, the mask's left and right gas delivery may each be performed by multiple nozzles.
(97) For example, as shown in
(98) In addition to the gas delivery nozzle pattern, the included angle between the gas flow path axis created by the left and right nozzles or nozzle patterns may be non-parallel. For example, as shown in
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(100) Nasal Mask with Jet Pump Throat:
(101) In addition, as shown in
(102) The jet pump throat section 1901 can be useful in creating consistent performance of the ventilation system from one person to another, by minimizing the effect of patient anatomy on performance. The jet pump throat section 1901 can also be useful in dampening the sound that is generated by the high velocity gas exiting gas delivery nozzles 1903 and entraining ambient air. The jet pump throat section 1901 can alternatively include entrainment ports 1905 at the base of the jet pump throat section 1901 as shown in
(103) The nozzle in
(104) Other Mask Form Factors:
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(106) The vertical extension arm 2107 can be adjustable to position the gas delivery nozzles 2103 at the appropriate distance from the user, and the horizontal extension arm 2105 can be rotate-ably adjustable to angle the gas delivery nozzles 2103 correctly to be in alignment with the nostril airway. The spacing between the gas delivery nozzles 2103 can be adjustable, for example by a linear adjustment in the horizontal arm.
(107) Breathing pressure sensing ports (not shown) may extend upward from the nose piece 2109 to be positively located at, near or inside the entrance to the nose. The nose piece 2109 may include a shelf 2113 at its bottom end which is used to position against the outside of the nostril rim. The breathing pressure sensing tube 2111 may be attached to one side of the nose piece 2109, the user's right side in
(108) The nasal mask 2101 may also include additional sensing functions such as a CO2 gas sampling port (not shown) and conduit extending to a capnometer (not shown), which can be included by integrating a secondary channel into the gas delivery tubing or pressure sensing tubing, and integrating the requsite channel into the mask nose piece and or extension arms. The nose piece 2109 may also prevent gas being delivered from the gas delivery nozzles 2103 from being directed toward the eyes when the nasal mask 2101 is not fitted properly to the user.
(109) The nasal mask 2101 may also include additional sensing functions such as a CO.sub.2 gas sampling port (not shown) and conduit extending to a capnometer (not shown). The nose piece 2109 may also prevent gas being delivered from the gas delivery nozzles 2103 from being directed toward the eyes when the nasal mask 2101 is not fitted properly to the user.
(110) This embodiment of the invention may use the angle of the medial aspect of the bridge of the nose to align the therapy to the patient. During testing, it was determined that the optimal performance was achieved when the gas delivery nozzles 2103 were aimed parallel to the bridge of the nose to align the jets of ventilation gas with the nares. The gas delivery nozzles 2103 of the nasal mask 2101 may be aimed parallel to the nose piece 2109, such that by placing the nose piece 2109 on the bridge of the nose, the gas delivery nozzles 2103 may be parallel to the bridge of the nose.
(111) If there is some misalignment, performance may degrade. The gas delivery nozzles 2103 preferably are kept within 10 degrees of being properly aligned with a nasal opening and an axis of the nares. As such, when a patient moves their nose to the left or right (e.g. by moving your jaw in an exaggerated manner), the nasal mask 2101 may follow the nose, ensuring that the gas delivery nozzles 2103 remain aligned with the centerline of the nose, and therefore the nostrils. In
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(113) The nasal air pressure sensing ports may be protrusions to help achieve a positive location of the sensing ports in the breath path in the nares. The gas delivery ports may be positioned such that the gas delivery path has a clear path to the nostril airway. There may be two or more sizes of nasal mask 2201, and or adjustment features in the mask, so that the sensing ports and gas delivery zones are properly aligned with the nasal airway path. The previous figures describe that the sensing locations must be in proximity to the entrance of the nostril, either inside, coplanar to the entrance, or slightly outside but if outside no more than 5 mm away from the entrance, whereas the gas delivery nozzle tips are located a distance from the entrance to the nostrils, for example 10-25 mm away. This configuration may allow the nasal mask 2201 to take advantage of the jet pump geometry, while not sacrificing sensing accuracy, so that the ventilator is in proper synchrony with the patient. Also, the gas flow profile may become more organized before entering the patient's nostril, rather than a turbulent jet entering the nostril, which would be quite uncomfortable and intolerant to the patient.
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(117) The following tables list exemplary values only and are not to be construed as limiting the disclosure.
(118) TABLE-US-00001 TABLE 1 Nasal Mask Exemplary Key Dimensions and Values Preferred/ Feature ideal Range Nozzle diameter: 0.033 in .010-.050 in Flow rate delivered to nozzle: 30 lpm 6-40 lpm Input pressure delivered to nozzle: 35 psi 5-60 psi Throat length, if included: .6-1.0 in .3-1.5 in Throat typical cross sectional area, 0.04 in.sup.2 0.02-0.06 in.sup.2 if included: Nozzle distance to proximal edge of 0.5-1.2 in 0.3-1.3 in nose:
(119) TABLE-US-00002 TABLE 2 Exemplary Ventilatory Support Parameters Preferred Parameter Range (Adult*) Lung Volume Augmentation (%) 10-150% 15-65% WOB reduction (%) 5-80% 10-50% Lung Pressure increase (cmH.sub.2O) 1-30 3-20 Upper Airway pressure increase 3-34 7-25 (cmH.sub.2O) Lung Pressure or Volume Waveform (1) R Entrained ambient air (% of Ventilator 10-300% 50-100% gas delivery) Gas exit speed out of gas delivery 25-350 50-200 nozzle (m/sec) Ventilator Output flow rate, average 5-40 10-20 (lpm) Gas Delivery Tubing outer diameter 3-7 4-6 (mm) Ventilator Output Pressure (psi) 10-60 20-40 Ventilator Drive Pressure (psi) 10-80 20-50 Ventilator Operating Pressure (psi) 5-40 25-35 Ventilator Output Volume (ml) 10-750 50-350 Ventilator Output Pulse Time (sec.) 0.100-1.25 0.200-0.750 Therapy's nominal source gas 0.5-6.0 2-4 consumption (lpm) Ventilator Output Synchronization (ms) variable variable depending on depending on comfort and comfort and need need (25-500 ms (75-250 ms delay) delay) Ventilator Output Waveform (1) Descending
(120) TABLE-US-00003 TABLE 3 Additional Exemplary Dimensions, Values and Materials Preferred Feature Range Range Dimensions Gas delivery hose, ID (mm) 2.0-7.0 2.5-4.5 Gas delivery hose, Length (ft), ambulating with 2-6 2.5-4 wearable system Gas delivery hose, Length (ft), ambulating with 20-75 40-60 stationary system Gas delivery hose, Length (ft), sleeping 4-15 6-10 Jet Nozzle, Length (mm) 0.5-15 2-10 Manifold Length (mm) 20-160 mm 30-80 mm Manifold spontaneous breathing gas flow path 0 ml 0 ml volume Manifold pressure sensing line diameter (in) .008-.055 .015-.040 Manifold breathing resistance 0 0.01-0.10 (cmH.sub.2O @ 60 lpm) Breathing sensing port, distance to nose (mm) 5 to 2 10 to 5 Materials Types Preferred Gas delivery hose PP, PE, PS, PVC PE Cannula PU, PVC, Silicone PVC, Silicone Manifold PVC, Silicone, PU, PE, Polysolfone PVC, Silicone Jet Nozzle Metal, Ultem, Nylon, LCP, PVC, PC, PVC ABS, PEEK (1) Square, Rounded, Descending, Ascending, Sinusoidal, Oscillating. * Dimensions listed are exemplary and for average sized adults; pediatric sizes 20% less, neonatal sizes 50% less. Diameters listed are effective diameters (average cross sectional dimension).
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(122) In the graph shown, the area inside the curve below the pressure axis is the inspiratory WOB, and the area defined by the area inside the curve above the pressure axis is the expiratory WOB. The arrows show the progression of a single breath over time, starting from RV to VT then returning from VT to RV. RV1 and VT1 are the residual volume and tidal volume without the therapy. Line 3201 represents spontaneous breathing without non-invasive open nasal ventilation. Line 3203 represents spontaneous breathing with non-invasive open nasal ventilation, with inspiratory augmentation and positive end-expiratory pressure (PEEP) therapy. RV2 and VT2 are the residual volume and tidal volume with the therapy. As can be seen, RV increases with the therapy because in this example, expiratory flow is provided as part of the therapy, which may increase residual volume. Importantly, VT is increased with the therapy and is increased more that the RV is increased, indicating that more volume is entering and leaving the lung as a result of the therapy. The increase in tidal volume is considered clinically efficacious, however is technically challenging to achieve in an open ventilation, non-invasive and minimally obtrusive system. As is shown in the graph, the patient's inspiratory WOB with the invention ON may be about 25% less than the patient's inspiratory WOB with the invention OFF. Also, inspiratory lung pressure increases (is less negative) and tidal volume increases, and optionally exhaled pressure increases if the therapy is provided during exhalation. While residual volume increases in the example shown because the ventilator is providing gas in this example during the expiratory phase, the ventilation parameters can be titrated to not effect residual volume, and because of the ability of the patient to exercise their lung muscles when receiving the therapy, the patient's lung mechanics may remodel in the case of COPD, actually causing a reduction of residual volume to a more normal value. In the graph shown, the waveform with therapy assumes an early inspiratory trigger time for the ventilator inspiratory phase therapy output, and that the volume output is delivered within the patient's inspiratory time. Optionally, however, different delivery waveforms and delivery synchronizations can be performed, which may adjust the WOB curve. For example, the ventilator inspiratory phase therapy can be delivered late in the person's inspiratory cycle, with delivery completing at the end of inspiration, and delivered with a square or ascending waveform profile. In this case the WOB curve with therapy will be tilted upward to the right of the curve, such that inspiration ends and transitions to exhalation at a point above the lung pressure zero axis.
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(133) The lung pressure resulting from the therapy may be governed by a combination of factors: the gas delivery circuit pressure, the jet pump design and configuration, the patient's lung compliance and airway resistance, the patient's breathing effort, the timing of the ventilator output relative to the patient's inspiratory phase, and the ventilator output waveform. Typically, however, a gas delivery circuit pressure of 30 psi delivering 100 ml with a square waveform, and delivered for 500 msec starting at the beginning of the patient's inspiratory phase, may increase lung pressure by 5-15 cmH2O. And, typically a gas delivery circuit pressure of 30 psi delivering 250 ml with a trapezoidal waveform, and delivered for 700 msec during the majority of the patient's inspiratory phase, may increase lung pressure by 10-25 cmH2O. The gas delivered by the ventilator can be oxygen, air, oxygen-air mixtures, or therapeutic gases such as helium. In a main mechanism of action of the invention, the patient's lung pressure and lung volume is increased, which allows the patient to exert them self without being limited by fatigue and dyspnea. In another main mechanism of action of the invention, the patient reduces their breathing effort in response to the pressure and volume support provided by the therapy, thus resulting in no change in total lung volume from the therapy, but resulting in a reduced work of breathing. In another main embodiment of the invention, a combination of the above two mechanisms of action can occur.
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(135) Although the foregoing description is directed to the preferred embodiments of the invention, it is noted that other variations and modifications will be apparent to those skilled in the art, and may be made without departing from the spirit or scope of the invention. Moreover, features described in connection with one embodiment of the invention may be used in conjunction with other embodiments, even if not explicitly stated above.