Gas scrubbing vent for patient interface

Abstract

A medical device is provided that has one or more improved comfort, cost, effectiveness, ease of use, and manufacturability for use in diagnosing, ameliorating, treating, or preventing respiratory disorders. [Solution] A gas cleaning vent and a patient interface with the gas cleaning vent configured to allow CO2 exhaled by a patient to flow outside the plenum chamber and minimize rebreathing of the exhaled CO2 by the patient, wherein the gas cleaning vent includes at least one exit orifice; a diffusion member at least partially covering the exit orifice; and a blocking member having an air-impermeable material, which prevents gas exiting the exit orifice from flowing directly into the diffusion member.

Description

[Technical Field]

[0001] The present technology relates to one or more of the detection, diagnosis, treatment, prevention and amelioration of respiratory-related disorders. The present technology also relates to medical devices or apparatus and their uses. [Background technology]

[0002] 1.2.1 The human respiratory system and its diseases The body's respiratory system facilitates gas exchange. The nose and mouth form the entrance to a patient's airways.

[0003] The airways contain a series of branches that become narrower, shorter, and more numerous as they penetrate deeper into the lungs. The primary function of the lungs is gas exchange, where oxygen is transferred from the air into the venous blood and carbon dioxide is carried out. The trachea divides into the left and right main bronchi, which then branch further into the terminal bronchioles. The bronchi make up the conducting airways and do not participate in gas exchange. The airways further divide into the respiratory bronchioles and ultimately into the alveoli. The alveolar regions of the lungs where gas exchange occurs are called the respiratory zone. See "Respiratory Physiology," by John B. West, Lippoincott Williams & Wilkins, 9th ed. 2011.

[0004] There is a spectrum of respiratory disorders, some of which can be characterized by specific events such as apnea, hypopnea and hyperpnea.

[0005] Obstructive sleep apnea (OSA) is a sleep-disordered breathing disorder (SDB) characterized by events involving closure or obstruction of the upper airway during sleep. This is the result of an abnormally small upper airway combined with the normal loss of muscle tone in the area of ​​the tongue, soft palate, and posterior oropharyngeal wall during sleep. Affected individuals typically stop breathing for 30 to 120 seconds, sometimes 200 to 300 times per night. Excessive daytime sleepiness is frequent, which can lead to cardiovascular disease and brain damage. This syndrome is particularly common in overweight, middle-aged men, although affected individuals may be unaware of the problem. See U.S. Patent 4,944,310 (Sullivan).

[0006] Cheyne-Stokes respiration (CSR) is another form of sleep-disordered breathing. CSR is a disorder of the patient's respiratory regulator, resulting in rhythmic alternating waxing and waning of breathing, known as CSR cycles. CSR is characterized by repeated deoxygenation and reoxygenation of arterial blood. CSR can be harmful due to repeated hypoxia. In some patients, CSR is associated with repeated arousals during sleep, which can result in severe sleep disruption, increased sympathetic nervous system activity, and increased afterload. See U.S. Patent 6,532,959 (Berthon-Jones).

[0007] Obesity hyperventilation syndrome (OHS) is defined as the combination of severe obesity and chronic awake hypercapnia in the absence of a known cause of hypoventilation. Symptoms include dyspnea, morning headache, and excessive daytime sleepiness.

[0008] Chronic obstructive pulmonary disease (COPD) includes any group of lower respiratory tract diseases that share certain characteristics. These include increased resistance to air movement, prolonged expiratory phase of breathing, and a decrease in normal lung elasticity. Examples of COPD are emphysema and chronic bronchitis. COPD is caused by regular smoking (the primary risk factor), occupational exposure, air pollution, and genetic factors. Symptoms include exertional dyspnea, chronic cough, and sputum production.

[0009] Neuromuscular diseases (NMDs) are a broad term encompassing many illnesses and conditions that impair muscle function either directly through underlying muscle lesions or indirectly through nerve lesions. Some NMD patients are characterized by progressive muscle impairment that leads to loss of ambulation, wheelchair confinement, swallowing difficulties, respiratory muscle weakness, and ultimately death from respiratory failure. Neuromuscular diseases can be divided into rapidly progressive and slowly progressive: (i) rapidly progressive diseases, characterized by months of muscle dysfunction and death within a few years (e.g., amyotrophic lateral sclerosis (ALS) and teenage Duchenne muscular dystrophy (DMD)); (ii) variable or slowly progressive diseases, characterized by worsening over several years and a slight reduction in life expectancy (e.g., limb-girdle, facioscapulohumeral muscular dystrophy, and myotonic dystrophy). Symptoms of respiratory failure in NMD include increasing general weakness, difficulty swallowing, dyspnea on exertion and at rest, fatigue, drowsiness, morning headache, difficulty concentrating, and difficulty shifting mood.

[0010] Chest wall disorders are a group of thoracic deformities that result in inadequate connection between the respiratory muscles and the rib cage. These disorders are usually characterized by restrictive obstruction and can lead to long-term hypercapnic respiratory failure. Scoliosis and / or kyphoscoliosis can lead to severe respiratory failure. Symptoms of respiratory failure include: exertional dyspnea, peripheral edema, orthopnea, recurrent pulmonary infections, morning headache, fatigue, poor sleep quality, and loss of appetite.

[0011] A variety of treatments have been used to treat or ameliorate these conditions, and in some cases, healthy individuals can take advantage of these treatments to prevent the onset of respiratory disease, but these have many drawbacks.

[0012] 1.2.2 Treatment Nasal continuous positive airway pressure (CPAP) therapy has been used to treat obstructive sleep apnea (OSA). The hypothesis is that continuous positive airway pressure acts as a pneumatic splint, pushing the soft palate and tongue forward and away from the posterior oropharyngeal wall, thereby preventing upper airway obstruction. Treatment of OSA with CPAP therapy is voluntary, and patients may opt out of this treatment if the device providing such treatment is one or more of the following: uncomfortable, difficult to use, expensive, and aesthetically unappealing.

[0013] Noninvasive ventilation (NIV) provides ventilatory support to a patient through the upper airway, performing some or all of the work of breathing to help the patient breathe adequately and / or maintain adequate oxygen levels. Ventilatory support is delivered via a patient interface. NIV has been used to treat CSR, OHS, COPD, MD, and chest wall disease. In some forms, it can improve the comfort and effectiveness of these treatments.

[0014] Invasive ventilation (IV) provides ventilatory support to patients who can no longer breathe effectively on their own and is delivered using a tracheostomy tube. Some forms can improve the comfort and effectiveness of these treatments.

[0015] 1.2.3 Diagnostic and therapeutic systems These treatments are provided by treatment systems or devices. Systems and devices can also be used to diagnose conditions without the use of treatments.

[0016] The therapy system consists of a respiratory pressure therapy (RPT) device, air circuit, humidifier, patient interface and data management.

[0017] 1.2.3.1 Patient Interface A patient interface can be used to interface a respiratory device to its wearer, for example, by providing airflow to the entrance of the airways. Airflow can be provided via a mask to the nose and / or mouth, a tube to the mouth, or a tracheostomy tube to the patient's trachea. Depending on the therapy being applied, the patient interface may form a seal, for example, to deliver gas to the patient's face, at a pressure sufficiently different from ambient pressure to be effective for the therapy, for example, at a positive pressure of approximately 10 cmH2O relative to ambient pressure. For other modes, such as oxygen delivery, the patient interface need not include a seal that allows delivery of gas to the airways at a positive pressure of approximately 10 cmH2O.

[0018] Patient interface design presents several challenges. The face has a complex three-dimensional shape. Nose size and shape vary considerably between individuals. The head contains bone, cartilage, and soft tissue, and different areas of the face respond differently to mechanical forces. The jaw or mandible can move in relation to the other bones of the skull. The entire head can move during respiratory therapy.

[0019] Because of these challenges, some masks suffer from one or more of the following problems: occlusiveness, aesthetic unpleasing, high cost, poor fit, difficulty to use, wear after extended use, or discomfort when the patient is unfamiliar with the system. For example, masks designed specifically for aviators, masks designed as part of personal protective equipment (e.g., filter masks), SCUBA masks, or masks for anesthesia administration may hold up for their intended use but are undesirably uncomfortable to wear for extended periods, e.g., several hours. This discomfort can lead to poor patient compliance with treatment, especially if the mask must be worn while sleeping.

[0020] CPAP therapy is particularly effective in treating certain respiratory conditions as long as the patient complies with the treatment. If the mask is uncomfortable or difficult to use, the patient may not comply with the treatment. Because patients are often encouraged to clean their masks regularly, if the mask is difficult to clean (e.g., difficult to assemble or disassemble), patients may not clean their masks, which affects patient compliance.

[0021] Masks intended for other applications (e.g., aviators) may not be appropriate for use with sleep-disordered breathing, but masks designed for use with sleep-disordered breathing may be suitable for other applications.

[0022] For these reasons, patient interfaces for the delivery of CPAP during sleep are a unique field.

[0023] 1.2.3.1.1 Seal forming part The patient interface includes a seal-forming portion that comes into direct contact with the patient's face, and the shape and configuration of the seal-forming portion can directly affect the effectiveness and comfort of the patient interface.

[0024] Patient interfaces are characterized in part by the design intent of where the seal-forming portion contacts the face during use. In one form of patient interface, the seal-forming portion can have two sub-portions, one for the left and one for the right nostril. In one form of patient interface, the seal-forming portion can be a single element that surrounds both nostrils during use. Such a single element can be designed, for example, to cover the upper lip region and the bridge of the nose region of the face. In one form of patient interface, the seal-forming portion can comprise an element that surrounds the mouth region during use, for example, forming a seal over the lower lip region of the face. In one form of patient interface, the seal-forming portion can comprise a single element that surrounds both nostrils and the mouth region during use. These different types of patient interfaces are known by various names given by their manufacturers, including nasal masks, full face masks, nasal pillows, nasal sprays, and nasal bridge masks.

[0025] A seal that is effective in one area of ​​a patient's face may not be suitable for another area due to differences in the shape, structure, variability, and sensitivity of the patient's face. For example, a seal on goggles that covers the patient's forehead may not be suitable for use on the patient's nose.

[0026] A seal-forming portion can be designed for mass production so that one design is comfortable and effective for a variety of different face shapes and sizes. Until there is a mismatch between the patient's face shape and the seal-forming portion of the mass-produced patient interface, one or both must be adapted to form a seal.

[0027] One type of seal-forming portion extends around the periphery of the patient interface, where the seal-forming portion attempts to engage the patient's face and is intended to seal against the patient's face when force is applied to the patient interface. The seal-forming portion can include an air- or liquid-filled cushion, or a molded or formed surface of a resilient sealing element made of an elastomer such as rubber. With this type of seal, if the fit is not proper, there will be a gap between the seal-forming portion and the face, requiring additional force to be applied to the patient interface against the face to form a seal.

[0028] Another type of seal-forming section includes a flap seal made of a thin material located near the periphery of the mask that self-seals against the patient's face when positive pressure is applied within the mask. As with the previous type of seal-forming section, if the fit between the face and the mask is not good, additional force is required to form a seal or the mask will leak. Furthermore, if the shape of the seal-forming section does not match that of the patient, it may wrinkle or bend during use, causing leakage.

[0029] Another type of seal-forming portion may include a mating element, such as a nostril insertion, which some patients find uncomfortable.

[0030] Another form of seal-forming part uses adhesives to achieve the seal, and some patients find it inconvenient to constantly apply and remove adhesive from the face.

[0031] Various patient interface seal forming technologies are disclosed in the following patent applications assigned to ResMed Limited: WO1998 / 004,310; WO2006 / 074,513; WO2010 / 135,785.

[0032] One form of nasal pillow is found in the Adam Circuit manufactured by Puritan Bennet. Another nasal pillow or nasal spray is the subject of U.S. Patent 4,782,832 (Trimble et al.), assigned to Puritan-Bennet Corporation.

[0033] ResMed Limited manufactured the following products incorporating nasal sprays: SWIFT TM (R) Nasal Pillows Mask, SWIFT TM II Nasal Pillow Mask, SWIFT TM LT Nasal Pillow Mask, SWIFT TM FX Nasal Pillow Mask and Mirage Liberty TM (registered trademark) Full Face Mask. Examples of nasal pillow masks are described in the following patent applications assigned to RedMed: International Patent Application WO 2004 / 073,778 (among others RedMed Limited SWIFT TM (Describing Features of Nasal Pillows), U.S. Patent Application 2009 / 0044808 (among others, RedMed Limited SWIFT TM LT Nasal Pillows); International Patent Applications WO2005 / 063,328 and WO2006 / 130,903 (in particular ResMed Limited MIRAGE LIBERTY TM International Patent Application WO2009 / 052,560 (in particular ResMed Limited SWIFT TM (Describes the features of the FX nasal pillow.)

[0034] 1.2.3.1.2 Positioning and stabilization The seal-forming portions of patient interfaces used in positive air therapy are subject to air pressure forces that tend to disrupt the seal. As such, various techniques have been used to position the seal-forming portion and maintain it in sealing relationship with the appropriate portion of the face.

[0035] One technique involves the use of adhesives, see for example US Patent Application No. US2010 / 0000534, however the use of adhesives can be uncomfortable for some patients.

[0036] Another technique involves the use of one or more straps and / or stabilizing harnesses. Many such harnesses suffer from one or more of the following problems: poor fit, bulkiness, discomfort, and awkwardness.

[0037] 1.2.3.1.3 Venting Technology Some forms of patient interface systems may include a vent for cleaning exhaled carbon dioxide. The vent may allow gas to flow from the patient interface interior space, e.g., a plenum chamber, to the exterior of the patient interface, e.g., to the atmosphere. The vent includes an orifice through which gas passes during mask use. Many such vents are noisy. Others become blocked during use and are inadequately cleaned. Some vents may disturb the sleep of the patient's 1000 bed partner 1100 due to noise or focusing of the airflow.

[0038] ResMed Limited has developed a number of improved mask venting technologies, see International Patent Application WO1998 / 034,665; International Patent Application WO2000 / 078,381; U.S. Patent No. 6,581,594; U.S. Patent Application US2009 / 0050156; and U.S. Patent Application 2009 / 0044808.

[0039] [Table 1]

[0040] (*Measured using only one sample in CRAP mode at 10cmH2O using the test method specified in ISO3744) The sound pressure of various objects is listed below.

[0041] [Table 2]

[0042] 1.2.3.2 Respiratory Pressure Therapy (RPT) Devices Air pressure generators are known for a variety of applications, such as industrial-scale ventilation systems. However, air pressure generators for medical use have specific requirements, such as reliability, size, and weight, that are not met by more general-purpose air pressure generators. Furthermore, even devices designed for medical use suffer from shortcomings related to one or more of comfort, noise, ease of use, efficiency, size, weight, manufacturability, cost, and reliability.

[0043] An example of a special requirement of some RPT devices is acoustic noise.

[0044] [Table 3]

[0045] One known RPT device used to treat sleep-disordered breathing is the S9 Sleep Therapy System manufactured by ResMed Limited. Another example of an RPT device is a mechanical ventilator. Mechanical ventilators, such as the ResMed Stella™ series of adult and pediatric ventilators, can provide invasive and non-invasive dependent respiratory support to a variety of patients treating a number of conditions, such as, but not limited to, NMD, OHS, and COPD.

[0046] ResMed Elisee TM ResMed VSIII with the ResMed 150 Ventilator TM (R) ventilators can provide support for invasive and non-invasive dependent ventilation suitable for adult or pediatric patients to treat a number of conditions. These ventilators provide volumetric and pressure-dependent breaths with single or dual limb circuits. RPT devices typically consist of a pressure generator, such as a motor-driven blower or compressed gas reservoir, and are configured to deliver a flow of air to the patient's airway. In some cases, the airflow can be delivered to the patient's airway at positive pressure. The outlet of the RPT device is connected to the patient interface via an air circuit.

[0047] 1.2.3.3 Humidifier Delivering airflow without humidification can dry out the airway. Using a humidifier with an RPT device and patient interface produces humidified gas, which minimizes drying of the nasal mucosa and increases patient airway comfort. Furthermore, in cooler climates, warm air applied to the face in and around the patient interface is much more comfortable than cool air. Various artificial humidifiers and systems are known, but they may not meet the special requirements of medical humidifiers.

[0048] Typically, medical humidifiers are used to increase the humidity and / or temperature of the airflow relative to the ambient air when a patient is sleeping or resting (e.g., in a hospital), if necessary. Bedside medical humidifiers can be small. Medical humidifiers can be configured to only humidify and / or heat the airflow delivered to the patient without humidifying and / or heating the area around the patient. For example, room-based systems (e.g., saunas, air conditioners, or evaporative coolers) can also humidify the air a patient breathes, but these systems can humidify and / or heat the entire room, causing discomfort to the occupants. Furthermore, medical humidifiers are subject to stricter safety restrictions than industrial humidifiers.

[0049] Many medical humidifiers are known, but these may suffer from one or more drawbacks: some provide inadequate humidification, and others are difficult or inconvenient for patients to use. Summary of the Invention [Means for solving the problem]

[0050] The present technology provides medical devices for use in diagnosing, ameliorating, treating or preventing respiratory disorders that have one or more improved comfort, cost, effectiveness, ease of use and manufacturability.

[0051] A first aspect of the present technology relates to a device for use in the diagnosis, amelioration, treatment or prevention of respiratory disease.

[0052] Another aspect of the technology relates to methods used in the diagnosis, amelioration, treatment or prevention of respiratory disorders.

[0053] An aspect of certain forms of the present technology is to provide methods and / or devices that improve patient compliance with respiratory therapy.

[0054] One form of the present technology includes at least one exit orifice; a diffusing member covering the exit orifice; and a blocking member having an air-impermeable member, wherein the blocking member prevents gas that has exited the exit orifice from flowing directly through the diffusing member.

[0055] Another aspect of one form of the present technology is a patient interface for sealed delivery of airflow at a continuous positive pressure relative to ambient pressure to a patient's airway entrance, the patient interface including at least one nasal entrance of the patient, wherein the patient interface maintains a therapeutic pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure during use throughout the patient's respiratory cycle while the patient is sleeping to improve sleep disordered breathing, the patient interface comprising: a sealing structure configured to seal around the patient's airway entrance; and a sealing structure configured to seal around the patient's airway entrance while maintaining the therapeutic pressure at the patient's airway entrance. a positioning and stabilizing structure that maintains the sealing structure in sealing contact with the surrounding area; a plenum chamber configured to be pressurized to a pressure above atmospheric pressure during use; a gas cleaning vent that allows CO2 exhaled by the patient to flow outside the plenum chamber to minimize rebreathing of CO2 by the patient, the gas cleaning vent including at least one exit orifice; a diffusion member at least partially covering the exit orifice; and a blocking member having an air-impermeable member that prevents gas exiting the exit orifice from flowing directly to the diffusion member.

[0056] In embodiments, (a) the diffusing member and block member are configured to direct gas exiting the exit orifice outward from the diffusing member in a direction different from the exit orifice; (b) the diffusing member provides a flow path parallel to a surface of the block member that abuts the diffusing member; (c) the diffusing member is a porous material; (d) the diffusing member is an open-cell foam; (e) the diffusing member is a fibrous material; (f) the block member is secured to the diffusing member along a surface of the block member that abuts the diffusing member; (g) the surface of the diffusing member is opposite the exit orifice with respect to the thickness of the diffusing member; (h) the patient interface further comprises a plurality of exit orifices; (i) the diffusing member overlies each of the plurality of exit orifices; (j) an axis defined by the center of an orifice is not perpendicular to a surface nearest the diffusing member; (k) the air impermeable material is a flexible material; and (l) the air impermeable material is a rigid material. material; (m) the patient interface further includes a channel configured to drain liquid from the exit orifice; (n) the orifice is within the channel; (o) the channel has a V-shaped or U-shaped cross-section; (p) the orifice is within a leg of the V-shaped or U-shaped cross-section; (q) the block member includes holes configured to redirect gas exiting the orifice; (r) the holes include multiple directions of holes configured to direct gas in multiple directions; (s) the diffusion member and the block member are removably attached to a plenum chamber; (t) the orifice is sized to result in substantially all pressure drop of gas passing through the irrigation vent and the diffusion member when subjected to a treatment pressure; (u) the orifice produces choked flow at treatment pressure; and / or (v) the orifice produces choked flow when the treatment pressure is approximately 4 cmH2O.

[0057] Another aspect of one form of the present technology is a gas irrigation vent for a patient interface configured to maintain a therapeutic pressure above ambient pressure in a range of about 4 cmH2O to about 30 cmH2O throughout a patient's respiratory cycle to ameliorate a sleep disorder while the patient is sleeping, the gas irrigation vent including: at least one exit orifice; a diffusion member covering the exit orifice; and a blocking member having an air-impermeable material, the blocking member preventing gas exiting the exit orifice from passing directly through the diffusion member.

[0058] In embodiments, (a) the diffusing member and block member are configured to direct gas exiting the exit orifice outward from the diffusing member in a direction different from the exit orifice; (b) the diffusing member provides a flow path parallel to a surface of the block member that abuts the diffusing member; (c) the diffusing member is a porous material; (d) the diffusing member is an open-cell foam; (e) the diffusing member is a fibrous material; (f) the block member is secured to the diffusing member along a surface of the block member that abuts the diffusing member; (g) the surface of the block member is opposite the exit orifice with respect to the thickness of the diffusing member; (h) the gas cleaning vent further includes a plurality of exit orifices; (i) the diffusing member covers each of the plurality of exit orifices; (j) an axis defined by the center of an orifice is not perpendicular to a surface of the diffusing member nearest the surface; (k) the air impermeable material is a flexible material; and (l) the air impermeable material is a rigid material. (m) the patient interface further comprises a channel configured to drain liquid from the exit orifice; (n) the orifice is within the channel; (o) the channel has a V-shaped or U-shaped cross-section; (p) the orifice is within a leg of the V-shaped or U-shaped cross-section; (q) the block member comprises holes configured to redirect gas exiting the orifice; (r) the holes comprise multiple directions of holes configured to direct gas in multiple directions; (s) the diffusing member and the block member are removably attached to a gas irrigation vent; (t) the orifice is sized to result in substantially all pressure drop of gas passing through the irrigation vent and the diffusing member when subjected to a treatment pressure; (u) the orifice produces choked flow at treatment pressure; and / or (v) the orifice produces choked flow when the treatment pressure is about 4 cmH2O.

[0059] Another aspect of one form of the present technology is a gas irrigation vent for a patient interface configured to maintain a therapeutic pressure above ambient pressure in a range of about 4 cmH2O to about 30 cmH2O throughout a patient's respiratory cycle to ameliorate a sleep disorder while the patient is sleeping, the gas irrigation vent comprising: at least one exit orifice defining a first axis; a diffusion member covering the exit orifice; and a blocking member having an air impermeable material; the blocking member preventing gas exiting the exit orifice from passing directly through the diffusion member, the blocking member having at least one hole therethrough, the hole defining a second axis, wherein the first axis and the second axis are not aligned or parallel.

[0060] In embodiments, (a) the first axis and the second axis form an angle of 15 to 75 degrees; (b) the first axis and the second axis form an angle of 30 to 60 degrees; (c) the gas cleaning vent includes a plurality of exit orifices and a plurality of holes; (d) at least one exit orifice is formed through the thickness of the material, and the first axis forms an acute angle with a normal to the surface of the material; the acute angle is 15 to 75 degrees; and / or (e) the acute angle is 30 to 60 degrees.

[0061] Of course, portions of the embodiments form sub-embodiments of the invention, and sub-embodiments and / or embodiments can be combined in various ways to form further embodiments or sub-embodiments of the technology.

[0062] Other features of the technology will become apparent from consideration of the information contained in the following detailed description, abstract, drawings, and claims.

[0063] 3.1 Treatment System The present technology is illustrated by way of example, and not by way of limitation, in the accompanying drawings, in which like reference numerals refer to like elements and in which: [Brief explanation of the drawings]

[0064] [Figure 1A]Figure 1A shows a system including a patient 1000 wearing a patient interface 3000 in the form of nasal pillows that receives a supply of air at positive pressure from an RPT device 4000. The air from the RPT device is humidified in a humidifier 5000 and supplied to the patient 1000 through an air circuit 4170. A bed partner 1100 is also shown. [Figure 1B] Figure 1B shows a system including a patient 1000 wearing a patient interface 3000 in the form of a nasal mask that receives a supply of air at positive pressure from an RPT device 4000. The air from the RPT device is humidified in a humidifier 5000 and supplied to the patient 1000 through an air circuit 4170. [Figure 1C] Figure 1C shows a system including a patient 1000 wearing a patient interface 3000 in the form of a full face mask that receives a supply of air at positive pressure from an RPT device 4000. The air from the RPT device is humidified in a humidifier 5000 and supplied to the patient 1000 through an air circuit 4170. [Figure 1D] Figure 1D shows a patient 1000 undergoing polysomnography (PSG). 3.2 Respiratory System and Facial Anatomy [Figure 2A] Figure 2A shows an overview of the human respiratory system, including the nasal and oral cavities, larynx, vocal cords, esophagus, trachea, bronchi, lungs, alveolar sacs, heart, and diaphragm. [Figure 2B] Figure 2B shows an overview of the human upper respiratory tract, including the nasal cavity, nasal bones, lateral nasal cartilages, greater alar cartilages, nostrils, upper lip, lower lip, larynx, hard palate, soft palate, oropharynx, tongue, epiglottis, vocal folds, esophagus, and trachea. [Figure 2C] Figure 2C is a front view of several features of the superficial anatomy, including the upper lip, upper vermilion, lower vermilion, lower lip, mouth width, endocanthion, alae of the nose, nasolabial folds, and cheilion. Additionally, superior, inferior, medial, and lateral radial directions are shown. [Figure 2D] Figure 2D is a lateral view of the head showing several features of the surface anatomy, including the glabella, therion, pronasal, subnasal point, upper lip, lower lip, supramenton, nasal ridge, alar crest point, superior and inferior ear base points, and also shows the superior and inferior directions and the anterior and posterior directions. [Figure 2E] Figure 2E is a further lateral view of the head, with the Frankfort horizontal and nasolabial angle also identified. The frontal plane is also shown. [Figure 2F] Figure 2F is a bottom view of the nose showing some of the features identified, including the nasolabial fold, lower lip, upper vermilion lip, nostrils, inferior nasal point, columella, pronasal passages, and the major and sagittal axes of the nostrils. [Figure 2G] FIG. 2G is a side view of the nasal surface features. [Figure 2H] Figure 2H shows the subcutaneous structures of the nose, including the lateral cartilage, septum cartilage, larger alar cartilage, smaller alar cartilage, sesamoid cartilage, nasal bones, epithelium, adipose tissue, frontal process of the maxilla, and fibroadipose tissue. [Figure 2I] Figure 2I shows the medial anatomy of the nose approximately a few millimeters from the sagittal plane, particularly the septal cartilage and medial crus of the greater alar cartilage. [Figure 2J] Figure 2J is a frontal view of the bones of the head, including the frontal nasal and zygomatic bones, with the nasal conchae shown as the upper and lower jaws. [Figure 2K] Figure 2K shows a lateral view of the contours of the head surface along with some muscles. The following bones are shown: frontal bone, sphenoid bone, nasal bone, zygomatic bone, maxilla, mandible, parietal skull, temporal and occipital bones. The mental protuberance is shown. The following muscles are shown: digastric, masseter, sternocleidomastoid, and trapezius. [Figure 2L] Figure 2L shows an anterolateral view of the nose. 3.3 Patient Interface [Figure 3A] FIG. 3A shows a patient interface in the form of a nasal mask in accordance with one form of the present technology. [Figure 3B] FIG. 3B shows a patient interface in the form of a full face mask, depicting various contoured areas of seal-forming structures such as a dome region, a saddle region, edge cushion surfaces, and holes in the cushion surfaces. [Figure 3C] FIG. 3C shows an exemplary profile of the seal-forming structure in cross section taken along line 3C-3C of FIG. 3B. [Figure 3D]FIG. 3D shows a bladder cushion of a full face mask, the bladder cushion having a toric surface and depicting a saddle region and a dome region. [Figure 3E] FIG. 3E shows an exemplary outline of the contour of the bladder cushion in cross section taken along line 3E-3E of FIG. 3D. [Figure 3F] FIG. 3F depicts a swivel and associated cylindrical region in accordance with one form of the present technology. [Figure 3G] FIG. 3G depicts an example of a saddle region. [Figure 3H] FIG. 3H depicts an example of negative and positive curves that combine to define the saddle region. [Figure 3I] FIG. 3I depicts an example of a dome region. [Figure 3J] FIG. 3J depicts an example of negative curves that combine to form the outline of a dome region. [Figure 4] FIG. 4 depicts the orifice and the diffusing and blocking members that form part of the gas washing vent. [Figure 5] FIG. 5 depicts a diffusion member and a blocking member that form part of a gas washing vent, with a hole in the blocking member. [Figure 6] FIG. 6 is an exploded view of the orifice, the diffusing member and the blocking member that form part of the gas cleaning vent, which are formed annularly around a central hole. [Figure 7] FIG. 7 depicts a simplified diagram of the orifice, diffusing element and blocking element that form part of the gas washing vent, which are formed annularly around a central hole. [Figure 8] FIG. 8 is a cross-sectional view taken along line 8-8 of FIG. [Figure 9A] FIG. 9A depicts a partial view of an elbow with a gas scrubbing vent with one annular outlet. [Figure 9B] FIG. 9B depicts an axial view of the orifice in the gas washing vent of FIG. 9B. [Figure 9C]FIG. 9C is a cross-sectional depiction taken through the plane of the drawing of FIG. 9B, equivalent to the section 9C-9C in FIG. 9B. [Figure 10A] FIG. 10A depicts an elbow with a ball and socket joint and a gas flushing vent. [Figure 10B] FIG. 10B depicts an exploded view of the elbow of FIG. 10A. [Figure 10C] FIG. 10C depicts a side view of the elbow. [Figure 10D] FIG. 10D depicts a cross-sectional view taken along line 10D-10D of FIG. 10C. DETAILED DESCRIPTION OF THE INVENTION

[0065] Before describing the present technology in further detail, it is to be understood that the present technology is not limited to the specific embodiments described herein, which may vary, and the terminology used in this disclosure is for the purpose of describing only the specific embodiments discussed herein, and is not intended to be limiting.

[0066] The following description is provided in terms of various embodiments that share one or more characteristics and / or features. It should be understood that one or more features of any one implementation may be combined with one or more features of another embodiment or other embodiments. Furthermore, any single feature or combination of features of any embodiment may constitute an additional embodiment.

[0067] 4.1 Treatment In one form, the present technology comprises a method of treating respiratory disorders comprising applying positive pressure to an airway entrance of a patient 1000.

[0068] In one embodiment of the present technology, air at positive pressure is delivered to the patient's nasal passages through one or both nostrils.

[0069] In some embodiments of the present technology, mouth breathing is limited, inhibited or prevented.

[0070] 4.2 Treatment System In one form, the present technology comprises an apparatus or device for treating a respiratory disorder, the apparatus or device including an RPT device 4000 that supplies pressurized air to a patient 1000 via an air circuit 4170 to a patient interface 3000.

[0071] 4.3 Patient Interface A non-invasive patient interface 3000 in accordance with one aspect of the present technology has the following functional aspects: a seal-forming structure 3100, a plenum chamber 3200, a positioning and stabilizing structure 3300, and a form of connection port 3600 for connection to an air circuit 4170. In some cases, the functional aspects may be provided by one or more physical components. In some forms, a single physical component may provide one or more functional aspects. In use, the seal-forming structure 3100 is positioned to surround the entrance to the patient's airways such that the supply of air to the airways is at positive pressure.

[0072] 4.3.1 Seal formation structure In one form of the present technology, a seal-forming structure 3100 provides a seal-forming surface and may also provide cushioning functionality.

[0073] The seal-forming structure 3100 according to the present technology can be constructed from a soft, flexible and resilient material such as silicone.

[0074] In one form, the seal-forming portion of the non-invasive patient interface 3000 includes a pair of nasal sprays or nasal pillows, each constructed and arranged to form a seal with a respective nostril of the patient's nose.

[0075] Nasal pillows according to aspects of the present technology include a mounting cone, at least a portion of which forms a seal with the underside of the patient's nose, legs, flexible portions at the base of the mounting cone and connecting the mounting cone to the legs. Additionally, the structure to which the nasal pillows of the present technology are connected includes flexible regions adjacent the bases of the legs. The flexible regions act in unison to act as a universal joint structure, accommodating both displacement and angular relative movement of the mounting cone and the structure to which the nasal pillows are connected. For example, the mounting cone can be displaced axially toward the structure to which the legs are connected.

[0076] In one form, the non-invasive patient interface 3000 includes a seal-forming portion that forms a seal with the upper lip portion of the patient's face (this is the lip superior) during use.

[0077] In one form, the non-invasive patient interface 3000 includes a seal-forming portion that forms a seal with the chin region of the patient's face during use.

[0078] 4.3.2 Plenum chamber The plenum chamber 3200 has a periphery 3210 (see FIG. 3c) that is shaped to complement the contoured surface of an average human face in the area where a seal will be formed during use. In use, the peripheral edge 3220 (see FIG. 3c) of the plenum chamber 3200 is positioned adjacent to the adjacent surface of the face. The actual contact with the face is made by the seal-forming structure 3100, which may extend around the entire periphery 3210 of the plenum chamber 3200 during use.

[0079] 4.3.3 Positioning and Stabilizing Structures 3300 The seal-forming portion 3100 of the patient interface 3000 of the present technology is held in a sealing position during use by a positioning and stabilising structure 3300.

[0080] In one form of the present technology, the positioning and stabilizing structure 3300 is configured to be suitable for being worn by a patient while sleeping. In one embodiment, the positioning and stabilizing structure 3300 has a low profile or cross-sectional thickness to reduce the volume of the grasping or actual device. In one embodiment, the positioning and stabilizing structure 3300 has at least one strap with a rectangular cross-section. In one embodiment, the positioning and stabilizing structure 3300 includes at least one flat strap.

[0081] In one form of the present technology, the positioning and stabilizing structure 3300 includes a strap made from a laminate of a patient-contacting layer of fabric, an inner layer of foam, and an outer layer of fabric. In one form, the foam is porous to allow moisture (e.g., sweat) to penetrate the strap. In one form, the outer layer of fabric includes loop material to engage portions of hook material.

[0082] In some forms of the present technology, the positioning and stabilizing structure 3300 comprises an elastic, e.g., elastically stretchable, strap. For example, the strap is configured to be stretched during use, directing a force to retract the cushion into sealing contact with portions of the patient's face. In some embodiments, the strap is configured as a fastener.

[0083] In one form of the present technology, the positioning and stabilizing structure 3300 comprises bendable, e.g., non-rigid straps. The advantage of this embodiment is that it is more comfortable for the patient to lie down while sleeping.

[0084] 4.3.4 Venting In one form, the patient interface 3000 includes a vent 3400 connected and arranged to scrub exhaled carbon dioxide, and is therefore also referred to as a gas scrubbing vent.

[0085] One form of vent 3400 according to the present technology includes a plurality of orifices 3402, such as from about 20 to about 80 orifices, or from about 40 to about 60 orifices, or from about 45 to about 55 orifices, including each whole integer in the stated ranges.

[0086] The vent 3400 may be located within the plenum chamber 3200. Alternatively, the vent 3400 may be located within an isolation structure 3500, such as a swivel (see Figure 3a).

[0087] FIG. 4 illustrates cross sections of several orifices 3402. The orifices 3402 are illustrated as holes through the wall 3404 of the plenum chamber 3200. However, the orifices 3402 can be located in locations other than the wall 3404. For example, the orifices 3402 can be located between the isolation structure 3500 and the connection port 3600 or in a portion of the air circuit 4170, preferably near the connection port 3600. The holes are illustrated with a diameter that is shorter than the axial length of the holes. The length and / or diameter can be selected to generate an appropriate flow rate when the plenum chamber 3200 is pressurized to a treatment pressure. The flow through the orifices 3402 is choked (e.g., at a Mach number of 1) at treatment pressures (e.g., 4 cmH2O or greater) or produces a flow rate less than the pressure drop sufficient to choke the flow. The choked flow results in substantially all of the pressure drop across the vent 3400 where the orifices 3402 are created. The arrows conceptually illustrate the direction of flow when the plenum chamber 3200 is pressurized above atmospheric pressure.

[0088] The orifices 3402 are formed through the thickness of the material of the wall 3404. Each of the orifices 3402 defines an axis, for example, along the center of the orifice. This axis forms an acute angle with a normal to the surface of the wall 3404. This angle can be between 15 and 75 degrees or between 30 and 60 degrees, including any whole number within the ranges described. For example, the angle can be approximately 45 degrees.

[0089] The orifice 3402 is covered with a diffusing member 3406 such that flow exiting the orifice 3402 impinges on and at least partially through the diffusing member 3406. The diffusing member 3406 can be formed from a material, such as a porous material, that allows gas to flow through the material but diffuses any jets or other flow formations exiting the orifice 3402. Some suitable examples of diffusing materials include nonwoven fibrous materials; woven fibrous materials; or open-cell foams. The diffusing material can be a medium similar to or the same as a filter media. The diffusing material 3406 can reduce the perceptible noise generated by the vent 3400 during use (e.g., when under therapeutic pressure).

[0090] The diffusion member 3406 is illustrated covered by a block member 3408 that prevents gas from flowing out of the orifice 3402 directly through the diffusion member 3406. The block member 3408 is constructed, at least in part, from an air-impermeable material. The air-impermeable material may be any suitable flexible or rigid material. For example, the air-impermeable material may be a hard plastic (e.g., molded polycarbonate) or a flexible plastic (e.g., plastic commercially available in sheet form). The block member 3408 may be molded integrally with the diffusion member 3406, molded separately but permanently attached to the diffusion member 3406, molded separately and removably in contact with the diffusion member 3406, or a combination thereof. The block member 3408 is illustrated opposite the exit orifice 3402 with respect to the thickness of the diffusion member 3406.

[0091] The block member redirects the flow (with respect to the direction through the orifice 3402) before exiting the diffusing member 3406. The block member 3408 and / or diffusing member 3406 are configured so that the flow exiting the orifice 3402 must flow at least a predetermined distance through the diffusing member 3406 before exiting the ambient atmosphere. The block member 3408 may also be configured to provide a particular direction and / or orientation so that the flow exiting the vent 3400 minimizes disturbance to the wearer and / or bed partner caused by the flow. For example, the block member 3408 may direct the gas through the diffusing member 3406 generally parallel to the surface of the block member 3408 nearest the diffusing member 3406.

[0092] In FIG. 4, the orifices 3402 and diffusing member 3406 are oriented relative to one another such that the central axes of each orifice are not perpendicular to the nearest surface of the diffusing member 3406, although a perpendicular arrangement is also possible as shown in FIG.

[0093] The channel 3410 can be applied to the outer surface of the wall 3404. The channel 3410 is illustrated as having a V-shaped cross section, but can be formed with any suitable cross section, such as, for example, a U-shape. The channel 3410 can be configured to drain liquid from one or more outlets of the orifice 3402. The orifice 3402 can be formed in the leg of the V-shape or U-shape.

[0094] Figure 5 illustrates an alternative configuration for the block member 3408. In Figure 5, the block member 3408 includes holes 3412. The holes 3412 can direct the outflow of the diffusion member 3406 opposite the orifice 3402, but in a different direction. The flow path is not a straight line through the orifice 3402 and the diffusion member 3406. The arrows associated with the holes 3412 are illustrated as parallel, but this is merely for ease of illustration. The holes 3412 can be configured to redirect flow in multiple directions.

[0095] Each hole 3412 is not aligned with or parallel to the axis defined by each orifice 3402. When viewed from the cross-section of Figure 5, any axis defined by a hole 3412 forms an angle with any axis defined by an orifice 3402. This angle can be between 15 degrees and 75 degrees, or between 30 degrees and 60 degrees, including any whole number in the ranges described. For example, the angle can be approximately 45 degrees.

[0096] Figures 6-8 illustrate alternative configurations of the vent 3400. Figure 6 is a partially exploded view, Figure 7 is a partially assembled view, and Figure 8 is a cross-sectional view taken along line 8-8 in Figure 7. In these figures, the orifices 3402 are illustrated in a circular array around a central hole 3414. This circular array is illustrated as including three main rows of holes, where the two innermost circular rows are closer together than the outermost circular rows, although any number of circular rows can be provided with equal spacing between the rows. The central hole 3414 allows fluid communication between the plenum chamber 3200 and the connection port 3600, and also with the air circuit 4170. A diffusion member 3406 and a block member 3408 are also illustrated as being disposed around the central hole 3414. In this configuration, the block member 3408 may be removably attached (e.g., a snap or screw mount that can be removed) or fixedly attached (e.g., a permanently bonded or a snap mount that must be broken to disassemble), and the diffusion member 3406 may or may not be fixedly held by the block member 3408. As best shown in FIG. 7, radial openings 3416 are provided to allow gas to exit the diffusion member 3406 radially outward from the central hole 3414.

[0097] Figures 9a through 9c illustrate another alternative configuration of vent 3400. Figure 9a is a partial view of the flow path of one form of elbow 3418, which may be disposed between isolation structure 3500 and connection port 3600 (both illustrated in Figure 3a), and includes vent 3400. This configuration largely obscures the features of vent 3400, so the remainder of the discussion will refer to Figures 9b and 9c.

[0098] FIG. 9b is an axial view without the cap 3422 and diffusing member 3406. The exit orifices 3402 are clearly visible in this view. Two annular rows are illustrated, each containing 40 exit orifices 3402. The orifices are offset so that the exit orifices 3402 in the inner and outer rows are radially aligned. This configuration allows for closer spacing of the annular rows. While two rows are illustrated, any number of rows can be provided, for example, one, three, or more. While 40 exit orifices 3402 are illustrated in each annular row, more or fewer orifices can be provided as needed to maintain an appropriate level of gas scrubbing. For example, one, five, 10, 15, 20, 25, 30, 35, 40, 45, 50, or more orifices 3402 per annular row, or any number in between, can be provided.

[0099] 9c, the annular array of orifices 3402 can be seen in cross section through wall 3420. Wall 3420 is similar to wall 3404, except that wall 3420 is illustrated separate from plenum chamber 3200; however, wall 3420 is part of plenum chamber 3200.

[0100] The diffusion member 3406 is illustrated as being ring-shaped with a rectangular cross section. The block member 3408 is illustrated as being a relatively thin sheet-like ring on the side of the diffusion member 3406 opposite the orifice 3402. The block member 3408 is attached to the diffusion member 3406 by any suitable method, such as, for example, an adhesive.

[0101] A cap 3422 is illustrated covering the diffusing member 3406 and the blocking member 3408. The cap 3422 abuts the blocking member 3408 such that the diffusing member 3406 is pressed against the wall 3420. Alternatively, the diffusing member 3406 does not have to be pressed against the wall 3420. The cap 3422 can serve as the blocking member, in which case the ring-shaped blocking member 3408 illustrated in FIG. 9c can be omitted.

[0102] The cap 3422 includes an angled annular flange 3424 that is spaced from the wall 3420 to form an annular gap 3426. The annular flange 3424 can also be considered skirt-like or frusto-conical. The annular gap 3426 provides a flow path for the ambient atmosphere so that the flow of the gas flushing is not unduly restricted. Alternatively, one or more openings (such as the radial openings 3416) can be provided in the annular flange 3424 to provide a flow path for the ambient atmosphere, thereby eliminating all or part of the annular gap 3426.

[0103] The cap 3422 is illustrated with an annular groove 3428 mated with an annular protrusion 3430 that holds the cap 3422 in place. The annular protrusions may be a series or multiple annularly spaced protrusions to form a snap fit, provide minimal or no interference with axial insertion, and provide a torsional configuration to hold the cap 3422 in place. In FIG. 9c, the annular protrusions 3430 are illustrated as three annularly spaced annular protrusions. The lips 3432 of the annular groove 3428 may be omitted at three corresponding locations, sized to provide minimal or no interference with the cap 3422 during axial insertion. Other forms of attachment are possible. For example, a threaded clamping arrangement may be provided, with the cap 3422 held in place by adhesive or welding. Releasable clamping, such as the illustrated configuration or a threaded connection, allows for replacement of the diffusion member 3406, for example, if the diffusion member becomes damaged, clogged, or contaminated.

[0104] Although the vent 3400 is illustrated on one side of the bend at the elbow 3418 (eg, upstream relative to the direction of exhalation), the vent 3400 may be upstream or downstream of the bend.

[0105] 10a through 10c illustrate another alternative configuration of a vent 3400. Like reference numerals are the same as above and will therefore not be described further except as follows. The vent 3400 in these figures is formed around an example of a separation structure 3500 that includes a ball 3434 and socket 3436 that are part of the elbow 3418. In the illustrated configuration, the ball 3434 and socket 3436 have three degrees of rotational freedom; however, several degrees of rotational freedom are possible, such as one or two degrees of rotational freedom.

[0106] As best seen in Figure 10d, the cap 3422 is connected to a first half 3440 located on the cap 3422 and a second half on the mating component by a snap-fit ​​connection 3438. Six of each of the first half 3440 and second half 3442 are provided between the radial openings 3416, three of which are visible in Figure 10a, although more or fewer may be provided as needed to obtain adequate retention and / or flow rate.

[0107] As best seen in FIG. 10c, 44 orifices 3402 are illustrated, evenly spaced in a single annular array. However, the number and spacing of the orifices 3402 can be configured differently. For example, fewer orifices 3402 can be provided if a lower flow rate is desired, and more orifices 3402 can be provided if a higher flow rate is desired. As explained above, more arrays can be provided. Also, the orifices need not be arranged in an annular array. If the orifices are located in locations other than those illustrated, they can be arranged in a grid based on Cartesian coordinates. Alternatively, the orifices 3402 need not be arranged in any type of array, but can be placed in random or pseudo-random locations.

[0108] 4.3.5 Separated Structures (Multiple) In one form, the patient interface 3000 includes at least one isolation structure 3500, such as a swivel or a ball and socket.

[0109] 4.3.6 Connection Port The connection port 3600 allows connection to the air circuit 4170 .

[0110] 4.3.7 Forehead support In one form, the patient interface 3000 includes a forehead support 3700 .

[0111] 4.3.8 Anti-breath valve In one form, the patient interface 3000 includes an anti-asphyxiation valve.

[0112] 4.3.9 Ports In one form of the present technology, the patient interface 3000 includes one or more ports that allow access to the volume within the plenum chamber 3200. In one form, the clinician can add supplemental oxygen. In one form, a property of the gas within the plenum chamber 3200, such as pressure, can be measured directly.

[0113] 4.4 Glossary For purposes of disclosure of this technology, one or more of the following definitions may apply in some forms of this technology. In other forms of this technology, alternative definitions may apply.

[0114] 4.4.1 General Air: In some forms of the present technology, air refers to atmospheric air, and in other forms of the present technology, air refers to some other combination of breathable gases, such as oxygen-rich atmospheric air.

[0115] Ambient: In certain forms of the present technology, the term ambient means (i) external to the treatment system or patient; (ii) immediately surrounding the treatment of the system or patient.

[0116] For example, the surroundings of the humidifier humidity is the humidity immediately surrounding the humidifier, such as the humidity in the room the patient is sleeping in. Such ambient humidity is different from the humidity outside the room the patient is sleeping in.

[0117] In another embodiment, the surrounding pressure is the pressure immediately surrounding or outside the body.

[0118] In some forms, the surrounding noise (e.g., acoustics) may be considered the background noise level in the room the patient is in, excluding, for example, noise generated by the RPT device or noise emanating from the mask or patient interface. Ambient noise originates from sources outside the room.

[0119] Continuous Positive Airway Pressure (CPAP) Therapy: CPAP therapy involves the application of air to the entrance of the airways at a pressure that is continuously positive relative to the atmosphere, with the pressure remaining approximately constant throughout the patient's respiratory cycle. In some forms, the pressure at the entrance of the airways is slightly higher during inhalation and slightly lower during exhalation. In some forms, the pressure varies during different respiratory cycles of the patient, for example, increasing in response to the detection of signs of partial obstruction of the patient's upper airway and decreasing in the absence of signs of partial obstruction of the upper airway.

[0120] Patient: A human being whether or not suffering from a respiratory disease.

[0121] Automatic Positive Airway Pressure (APAP) Therapy: For example, CRAP therapy in which the therapy pressure is automatically adjusted from breath to breath, between minimum and maximum, depending on the presence or absence of an SDB event.

[0122] 4.4.2 Aspects of the respiratory rate cycle Apnea: According to some definitions, apnea is said to occur when flow drops below a predetermined threshold for a period of time, e.g., 10 seconds. Obstructive apnea is said to occur when air does not flow due to an obstructed airway despite the patient's efforts. Central apnea is said to occur when apnea is detected by a decreased or no respiratory effort despite an open airway. Mixed apnea is said to occur when a decreased or absent respiratory effort occurs simultaneously with an obstructed airway.

[0123] Respiratory rate: The rate at which a patient is spontaneously breathing, usually measured in breaths per minute.

[0124] Duty cycle: ratio of inhalation time, ratio of total breathing time to Ti, Tiot.

[0125] Effort (Respiratory): Respiratory effort is described as the work done by the patient's spontaneous breathing in an attempt to breathe.

[0126] Expiratory portion of the respiratory cycle: the period from the start of expiratory flow to the start of inspiratory flow.

[0127] Flow limitation: Flow limitation is understood as a condition in the patient's respiratory effort where the patient's efforts do not result in a corresponding increase in flow. When flow limitation occurs during the inspiratory portion of the respiratory cycle, it is described as inspiratory flow limitation. When flow limitation occurs during the expiratory portion of the respiratory cycle, it is described as expiratory flow limitation.

[0128] Flow-limited inspiration waveform types: (i) Flattened: There is an ascent, followed by a relatively flat area, and then a descent. (ii) M-type: There are two local peaks, one at the leading edge and one at the trailing edge, with a relatively flat area between the two peaks. (iii) Chair-shaped: There is a single local peak at the leading edge followed by a relatively flat area. (iv) Inverted chair shape: a relatively flat area followed by a single local peak at the trailing edge.

[0129] Hypopnea: Preferably, hypopnea refers to a decrease in flow, not an interruption of flow. In one form, hypopnea occurs when there is a period of time where flow is reduced below threshold. When hypopnea occurs due to a reduction in respiratory effort, central apnea occurs. In one form in adults, any of the following can be considered hypopneas: (i) The patient's breathing decreases by 30% for at least 10 seconds with an associated desaturation of 4%; or (ii) The patient's breathing is reduced (but not more than 50%) for at least 10 seconds, and there is an associated desaturation or arousal of at least 3%.

[0130] Hyperventilation: An increase in flow to a level higher than normal.

[0131] Inspiratory Portion of the Respiratory Cycle: The period from the start of the inspiratory flow to the start of the expiratory flow is called the inspiratory portion of the respiratory cycle.

[0132] Patency (Airway): The degree to which the airway is open or the degree to which the airway is open. A patent airway is open. Airway patency is quantified with a value of one (1) being open and a value of zero (0) being closed.

[0133] Positive end-expiratory pressure (PEEP): Pressure above atmospheric pressure in the lungs that exists at the end of expiration.

[0134] Peak flow (Qpeak): The maximum value of flow during the inspiratory portion of the respiratory airflow waveform.

[0135] Respiratory flow, airflow, patient airflow, respiratory airflow (Qr); these synonyms may be understood to refer to the RPT device's estimate of respiratory flow, as opposed to the actual respiratory flow experienced by the patient, "true respiratory flow" or "true respiratory airflow", usually expressed in liters per minute.

[0136] Tidal volume (Vt): The volume of air inhaled or exhaled during normal breathing without extra effort.

[0137] (Inspiratory Time) (Ti): The duration of the inspiratory portion of the respiratory flow waveform.

[0138] (Expiratory) Time (Te): The duration of the respiratory portion of the respiratory airflow waveform.

[0139] (Total) Time (Ttot): The total duration between the start of the inspiratory portion of one respiratory flow waveform and the start of the inspiratory portion of the following respiratory flow waveform.

[0140] Typical Recent Ventilation: The ventilation value around which recent values ​​tend to cluster over a given time scale; i.e., a measure of central tendency for recent values ​​of ventilation.

[0141] Upper airway obstruction (UAO) includes both partial and total upper airway obstruction. It is associated with a state of flow limitation, where increasing pressure differentials across the upper airway can result in slightly increased or even decreased levels of flow (Starling-Register behavior).

[0142] Vent: A measure of the total amount of gas exchanged by a patient's respiratory system. Measurements of ventilation include one or both of the inspiratory flow and expiratory flow per unit of time. When expressed as volume per minute, this amount is often called "minute ventilation." Minute ventilation is sometimes given simply as volume and is understood as volume per minute.

[0143] 4.4.3 RPT device parameters Flow: The instantaneous volume (or mass) of air delivered per unit time. Flow and ventilation have the same magnitude of volume or mass per unit time. Flow is measured over a much shorter period of time. Sometimes, references to flow are to a scalar quantity, i.e., a quantity with magnitude only. Other times, references to flow are to a vector quantity, i.e., a quantity with both magnitude and direction. When a signed quantity, flow is nominally positive during the inspiratory portion of the patient's respiratory cycle and therefore negative during the expiratory portion of the patient's respiratory cycle. Flow is given by the symbol Q. "Flow" is sometimes shortened to simply "flow." Total flow, Qt, is the flow of air exiting the PAP device. Vent flow, Qv, is the flow of air leaving the vent to scavenge exhaled gases. Leakage flow, Ql, is the flow of leakage from the patient interface system. Respiratory flow, Qr, is the flow of air received by the patient's respiratory system.

[0144] Leak: The term leak is understood to mean an unintended flow of air. In one embodiment, a leak is the result of an incomplete seal between the mask and the patient interface. In another example, a leak occurs in the swivel elbow.

[0145] Noise, Conducted (Acoustic): As used herein, conducted noise refers to noise transmitted to the patient in an airway, such as the air circuit and patient interface and the air therein. In one form, conducted noise is quantified by measuring the sound pressure at the end of the air circuit.

[0146] Noise, radiated (acoustic): Radiated noise herein refers to noise brought to the patient by the ambient air. In one form, radiated noise is quantified by measuring the sound power / pressure level of the object in question according to ISO 3744.

[0147] Noise, Vent (Acoustic): Vent noise, as used herein, refers to the noise generated by the airflow through any vents, such as holes in the patient interface.

[0148] Pressure: Force acting on a unit area. Pressure is expressed in cmH2O or gf / cm 2 It is measured in various units such as hectopascals and 1cmH2O is 1g-f / cm 2 which is approximately 0.98 hectopascals. Unless otherwise specified, pressures are given herein in cmH2O. The pressure at the patient interface is given by the symbol Pm, and the therapeutic pressure, which indicates the target value to be achieved at the mask pressure Pm at the current time, is given by Pt.

[0149] Sound power: The energy carried by a sound wave per unit time. Sound power is proportional to the square of the sound pressure multiplied by the area of ​​the wavefront. Sound power is usually given in decibels (SWL), which are stated in terms of a reference power, usually in the range of 10 -12 It is said to be a watt.

[0150] Sound pressure: the local deviation from ambient pressure at a given time resulting from sound waves passing through a medium. Sound pressure is usually described in SPL, i.e., relative to a reference pressure, usually 20 x 10 -6 It is measured in pascals (Pa) and is considered the threshold of human hearing.

[0151] 4.4.4 Ventilator terminology Adaptive servo-ventilator (ASV): A servo-ventilator with a variable rather than fixed target ventilation. The variable target ventilation can be learned from some characteristics of the patient, such as the patient's breathing characteristics.

[0152] Backup Rate: A ventilator parameter that determines the minimum number of breaths (typically in breaths per minute) that the ventilator will deliver to the patient if not triggered by spontaneous respiratory effort.

[0153] Cycled: The end of the inspiratory phase of a ventilator. When a ventilator is delivering breaths to a spontaneously breathing patient, at the end of the inspiratory portion of the respiratory cycle, the ventilator is said to be cycled so that it stops delivering breaths.

[0154] EPAP: The base pressure to which fluctuating pressure is applied during breathing to generate the desired mask pressure the ventilator attempts to achieve at any given time.

[0155] IPAP: The desired mask pressure that the ventilator attempts to achieve during the inspiratory portion of the breath.

[0156] Pressure Support: A number that indicates the increase in pressure during expiration in a ventilator, meaning the difference in pressure between the maximum value during expiration and the minimum value when breathing out (e.g., PS = IPAP - EPAP). In some situations, Pressure Support refers to the difference the ventilator intends to achieve rather than what the ventilator actually achieves.

[0157] Servo-ventilator: A ventilator that measures the patient's ventilation and has a target ventilation, which adjusts the level of pressure support to direct the patient's ventilation toward the target ventilation.

[0158] Spontaneous / Timed (S / T): A mode of a ventilator or other device that attempts to detect the onset of a breath in a spontaneously breathing patient, but if the device does not sense a breath within a predetermined time, the device automatically begins delivering a breath.

[0159] Swing: Equivalent term for pressure support.

[0160] Triggered: When the ventilator delivers a breath of air to a spontaneously breathing patient, it is said to be triggered at the start of the expiratory portion of the respiratory cycle due to patient effort.

[0161] Typical Recent Ventilation: Typical recent ventilation Vtyp is the value around which recent measurements of ventilation over a given time scale tend to cluster. For example, a measure of the central tendency of measurements of ventilation over the recent history would be an appropriate value for typical recent ventilation.

[0162] Ventilator: A mechanical device that provides pressure support to a patient and performs some or all of the work of breathing.

[0163] 4.4.5 Facial Anatomy Alar: the outer wall or “wing” of each nostril (plural: alar).

[0164] Alar: the lateral-most point of the wing of the nose.

[0165] Alar curvature (or alar apex) point: the most posterior point on the curvature baseline of each wing, found in the crease formed by the junction of the wing and cheek.

[0166] Pinna: the entire external visible part of the ear.

[0167] (Nasal) skeleton: The nasal skeleton consists of the nasal bones, the frontal process of the maxilla, and the nasal part of the frontal bone.

[0168] (Nasal) Symchondral Skeleton: The symchondral skeleton of the nose consists of the interseptal, lateral, major and minor cartilages.

[0169] Axillary column: a strip of skin that separates the nostrils and runs anteriorly from the nose to the upper lip.

[0170] Axial-columnar angle: the angle between a line passing through the middle of the nostril opening and a line perpendicular to the Frankfurt horizontal that crosses the underside of the nose.

[0171] Frankfurt horizontal plane: a line extending from the lowest part of the orbital rim to the left auricular point, which is the deepest point in the notch of the auricle above the tragus.

[0172] Glabella: Located in the soft tissue, the most prominent point in the midsagittal plane of the forehead.

[0173] Lateral nasal cartilage: a generally triangular plate of cartilage whose upper margin is attached to the nasal bone and frontal process of the maxilla, and whose lower margin is connected to the greater alar cartilage.

[0174] Lower lip (labralei inferius):

[0175] Upper lip (Labraria superioris):

[0176] Major alar cartilage: a cartilaginous surface lying beneath the lateral nasal cartilage. It curves around the anterior part of the nostril. Its upper end is connected to the cartilaginous frontal process by a tough fibrous membrane containing three or four minor alar cartilages.

[0177] Nostril (nostril): roughly oval opening that forms the entrance to the nasal cavity. The singular form of nostril is nostril. The nostrils are separated by the nasal septum.

[0178] Nasolabial fold or nasolabial fold: a fold of skin or dermal groove that runs from each side of the nose to the corner of the mouth, separating the cheek from the upper lip.

[0179] Naso-labial angle: the angle between the axis and the upper lip, crossing the underside of the nose.

[0180] Inferior auricular point: the lowest point of attachment of the pinna to the skin of the face.

[0181] Superior auricular point: the uppermost point of attachment of the pinna to the skin of the face.

[0182] Anterior nose: the most prominent point or tip of the nose, identifiable in a lateral view of the rest of the head.

[0183] Subnasal depression: a median groove running from the lower border of the nasal septum to the top of the lip in the upper lip region.

[0184] Mandibular point: Located in the soft tissue, the most anterior midpoint of the jaw.

[0185] Nasal process (nasal): The nasal process is a midline prominence of the nose, extending from therion to the pronazare.

[0186] Sagittal plane: the vertical plane running from front to back and dividing the body into right and left halves.

[0187] Therion: The most concave point in the soft tissue, covering the area of ​​the frontal suture.

[0188] Nasal septum cartilage (nose): The nasal septum cartilage forms part of the septum, separating the anterior part of the nasal cavity.

[0189] Subala: The point on the lower edge of the wing base where it joins the skin of the upper lip.

[0190] Nasal spine point: Located in soft tissue, this point meets the upper lip in the midsagittal plane.

[0191] Supramentale: Point of greatest concavity in the midline of the lower lip between the upper labial teeth and the soft tissue pogonion.

[0192] 4.4.6 Skull anatomy Frontal bone: The frontal bone contains a large vertical portion, the scales frontalis, corresponding to the area known as the forehead.

[0193] Mandible: The mandible forms the lower jaw. The mental protuberance is the bony prominence of the jaw that forms the jaw.

[0194] Maxilla: The maxilla forms the upper jaw and lies above the mandible and below the orbit. The frontal process of the maxilla projects upwards next to the nose and forms the anterior part of its lateral border.

[0195] Nasal bones: The nasal bones are two small, oval bones that vary in size and shape between individuals; they lie side by side in the middle and upper part of the face and together form the "proboscis" of the nose.

[0196] Nasal base: the intersection of the frontal bone and the two nasal bones, a depression between the eyes and the top of the nasal prominence.

[0197] Occipital bone: The occipital bone is located at the back and bottom of the skull. It contains an oval opening, the foramen magnum, through which the cranial cavity communicates with the spinal canal. The curved surface behind the foramen magnum is the occipital squama.

[0198] Orbit: bony cavity within the skull that contains the eyeball.

[0199] Parietal bones: bones that when fused form the top and sides of the skull.

[0200] Temporal bone: The temporal bone is located at the base and sides of the skull and supports parts of the face known as the temples.

[0201] Cheekbones: The two cheekbones located at the top and sides of the face form the cheek prominences. 4.4.7 Anatomy of the Respiratory System

[0202] Diaphragm: A sheet of muscle that stretches across the base of the rib cage. The diaphragm separates the thoracic cavity, which contains the heart, lungs, and ribs, from the abdominal cavity. When the diaphragm contracts, it increases the volume of the rib cage and draws air into the lungs.

[0203] Larynx: The larynx, or larynx, houses the vocal cords and connects the lower part of the pharynx (hypopharynx) to the trachea.

[0204] Lung: respiratory organ in humans. The conducting zone of the lung includes the trachea, bronchi, bronchioles, and terminal bronchioles. The respiratory zone includes the respiratory bronchioles, alveolar ducts, and alveoli.

[0205] Nasal Cavity: The nasal cavity (or nasal fossa) is an air-filled space in the center of the face, above and behind the nose. The nasal cavity is divided into two halves by a vertical fin called the nasal septum. On the nasal side, there are three horizontal outgrowths called nasal conchae (singular "concha") or turbinates. The nose is located in front of the nasal cavity, and at the back, it merges into the nasopharynx via the choanae.

[0206] Pharynx: Located just below (below) the nasal cavity and above the esophagus and pharynx is the part of the throat. The pharynx is usually divided into three sections: the nasopharynx (nasopharynx) (nasal part of the pharynx), the oropharynx (middle pharynx) (oral part of the pharynx), and the laryngopharynx (hypopharynx).

[0207] 4.4.8 Materials Silicone or Silicone Elastomer: Synthetic rubber. Herein, silicone refers to liquid silicone rubber (LSR) or compression-molded silicone rubber (CMSR). One commercially available form of LSR is SILASTIC (included in the range of products sold under this trademark) manufactured by Dow Corning. Another manufacturer of LSR is Wacker. Unless otherwise specified, exemplary forms of LSR have a Shore A (or Type A) indentation hardness in the range of about 35 to 45, measured according to ASTM D2240.

[0208] Polycarbonate: A typically transparent thermoplastic polymer of bisphenol-A carbonate.

[0209] 4.4.9 Patient Interface Aspects Anti-asphyxiation valve (AAV): A component or subassembly of a mask system that, when vented to atmosphere in a fail-safe manner, reduces the patient's risk of excessive CO2 rebreathing.

[0210] Elbow: A conduit that changes the axis of airflow and redirects it through an angle. In one form, the angle may be approximately 90 degrees. In another form, the angle may be less than 90 degrees. The conduit has a generally circular cross section. In another form, the conduit may have an oval or rectangular cross section.

[0211] Frame: Frame refers to the mask structure that bears the load of tension between two or more connection points with the headgear. The mask frame may be a non-airtight, load-bearing structure in the mask, although some forms of mask frames may also be airtight.

[0212] Headgear: Headgear may be taken to mean any form of positioning and stabilizing structure designed for use on the head. Preferably, the headgear includes one or more braces, retainers, and stiffeners configured to position and hold the patient interface in place on the patient's face for delivery of respiratory therapy. Some retainers are formed from a soft, flexible, resilient material, such as a laminated composite of foam and fabric.

[0213] Membrane: Preferably understood to mean a typically thin element that is substantially impervious to bending but resistant to stretching.

[0214] Plenum chamber: Mask plenum chamber is understood to mean a part of the patient interface having walls enclosing a volume within which, during use, air is pressurized above atmosphere. The shell may form part of the mask plenum chamber.

[0215] Seal: The noun form (“a seal”) is taken to mean a structure or barrier that intentionally resists the flow of air through the interface of two surfaces. The verb form (“to seal”) is taken to mean to resist the flow of air.

[0216] Shell: A shell is understood to mean a curved, relatively thin structure that has bending, tensile, and compressive rigidity. For example, the curved structural wall of a mask can be a shell. In some embodiments, the shell can be faceted. In some cases, the shell can be airtight. In some cases, the shell can be non-airtight.

[0217] Stiffener: Stiffener is understood to mean a structural component designed to increase the bending resistance of another component in at least one direction.

[0218] Bracing: Bracing is understood to mean a structural component designed to increase the compressive resistance of another component in at least one direction.

[0219] Swivel: (noun) An assembly of components configured to rotate about a common axis, preferably independently, and preferably under low torque. In one form, the swivel may be constructed to rotate at least 360 degrees. In another form, the swivel may be constructed to rotate less than 360 degrees. When used in the context of air delivery conduits, the component subassembly preferably includes a matched pair of cylindrical conduits. During use, there is little or no air leakage from the swivel.

[0220] Anchorage: Anchorage can be interpreted to mean a structural component designed to resist tension forces.

[0221] Vent: (noun) A structure that provides a deliberate flow of air from the interior of a mask or conduit to the ambient air, e.g., to clean exhaled gases.

[0222] 4.4.10 Terminology used in relation to patient interfaces Curvature (at a point on a surface): At a point p on a surface, there is a normal (e.g. perpendicular to the outer surface). Each plane containing the normal (a 'normal plane') cuts the surface and defines a curve. The curvature of that curve at p can be described as having a sign and a magnitude (e.g. 1 / radius of the circle tangent to the curve at p). The directions of the normal plane where the curve has its maxima and minima are called the principal directions. The principal curvatures at p are the curvatures in the principal directions.

[0223] Curvature (of a surface): A region of a surface that has a saddle shape that curves up in one direction and down in a different direction is said to have negative curvature. A region of a surface that has a dome shape that curves equally in both major directions is said to have positive curvature. A flat surface is considered to have zero curvature.

[0224] Cylindrical region: A surface region containing a path, where each point in the region near the path has zero curvature (or effectively zero curvature) tangent to the path and non-zero curvature in the direction perpendicular to the path.

[0225] Dome area: the set of points on a surface whose principal curvatures have the same sign, e.g., all positive or all negative.

[0226] Edge (of a surface): the boundary or limit of a surface.

[0227] Floppy: A quality of material, construction, or composite that is one or more of the following: · Follow the acupressure immediately. · It cannot maintain its shape when it has to support its own weight. -Not rigid. · Can be stretched and bent elastically with little effort.

[0228] The quality of being floppy is related to direction, so that a particular material, structure, or composition may be floppy in a first direction, but stiff or rigid in a second direction, such as a second direction perpendicular to the first direction.

[0229] Intersection of two surfaces: the path where two surfaces meet.

[0230] Negative curvature: If the curve at p deviates from the normal (e.g., concave downward), the curvature in that direction at that point is considered negative.

[0231] Path: In some aspects of the present technology, a 'path' refers to a path in the mathematical-topological sense, e.g., a continuous space on a surface from f(0) to f(1). In some aspects of the present technology, a 'path' includes, e.g., a set of points on a surface, and is described as a route or course.

[0232] Patient's perspective: The direction of the object as it would appear to the patient during normal use.

[0233] Planar Region: A surface region where both principal curvatures are zero (or zero, for example, within manufacturing tolerances).

[0234] Positive curvature: If the curve at p points towards the normal (e.g., concave up), then the curvature at that point in that direction is considered positive.

[0235] Resilient: Capable of substantial elastic deformation and releasing substantially all of its energy in a relatively short time, e.g., 1 second, when the load is removed.

[0236] Ridge: A region of a surface where the curvature in the first direction at each point is non-zero and has the same magnitude and sign.

[0237] Rigid: Does not easily deform under finger pressure and / or tension or loads typically encountered when setting up and maintaining a patient interface in sealing relationship with the patient's airway entrance.

[0238] Surface Labeling: Some physical structures according to the present technology can include one or more surfaces. Such surfaces can be distinguished using labels that describe the orientation, location, function, or some other characteristic of the associated surfaces. For example, a structure may comprise one or more of a front, back, inner, and outer surface. In another example, a cushioning structure may comprise a face-contacting (e.g., outer) surface and a separate, non-face-contacting (e.g., lower or inner) surface. In another embodiment, the structure comprises a first surface and a second surface.

[0239] Semi-rigid: means sufficiently rigid so as not to deform substantially under the influence of mechanical forces typically applied during respiratory pressure therapy.

[0240] Saddle area: A set of points on a surface where at each point in the set, the principal curvatures have opposite signs, one positive and one negative.

[0241] Surface: A set of three-dimensional points described by two independently varying parameters, e.g., a sphere is parameterized by latitude and longitude.

[0242] 4.5 Other notes A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to anyone making a facsimile reproduction of the patent document or the patent disclosure so long as it appears in the Patent and Trademark Office patent file or records. Otherwise, all copyright is reserved.

[0243] Unless the context clearly dictates otherwise, and unless a range of values ​​is described, each intervening value, between the upper and lower limits of that range, to one-tenth of the unit of the lower limit, and any other stated or intervening value in that stated range, is encompassed within the technology. The upper and lower limits of these intervening ranges may be independently included in the intervening ranges, and are encompassed within the technology, subject to any specifically excluded limit in the stated range. When a stated range includes one or both limits, ranges excluding either or both of those included limits are also encompassed within the technology.

[0244] Furthermore, where one or more values ​​are described as being incorporated herein as part of the technology, unless otherwise specified, it will be understood that such values ​​may be approximated and may utilize any suitable significant digits to the extent practical technology implementation permits or requires.

[0245] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this technology belongs. Although any methods or materials similar or equivalent to those described herein can also be used in the practice or testing of the present technology, a limited number of exemplary methods and materials are described herein.

[0246] Where a particular material is identified as being used to construct a component, obviously alternative materials having similar properties may be used as a substitute. Further, unless otherwise specified to the contrary, it is understood that any and all components described herein may be manufacturable and therefore may be manufactured together or separately.

[0247] It should be noted that as used in this specification and the appended claims, the singular forms "a," "an," and "the" include the plural forms unless the context clearly dictates otherwise.

[0248] All publications mentioned herein are incorporated by reference to disclose and describe the methods and / or materials that are the subject of such publications. The publications discussed herein are provided for their disclosure prior to the filing date of the present application. Nothing contained herein should be construed as an admission that the present technology is entitled to antedate such publication by virtue of prior invention. Further, the publication dates provided may be different from the actual publication dates and each must be independently confirmed.

[0249] The words "comprises" and "comprising" when referring to elements, components, or steps, should be construed in a non-exclusive manner such that the referenced element, component, or step is intended to be combined with any other elements, components, or steps that may be present or utilized or that are not expressly referenced.

[0250] The subject headings used in the detailed description are included solely for the reader's ease of reference and should not be used to limit the subject matter found throughout the disclosure or claims. The subject headings should not be used to construe the scope of the claims or claim limitations.

[0251] Although the technology described herein has been described with reference to particular embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the technology. In some cases, terms and symbols may imply specific details not required to practice the technology. For example, the terms "first" and "second" are used unless otherwise noted, but they are not intended to imply any order and may be used to distinguish between distinct elements. Furthermore, while process steps in a methodology may be described or illustrated in order, such order is not required. Those skilled in the art will recognize that such order may be modified and / or that features may be performed simultaneously or synchronously.

[0252] It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the technology. [Explanation of symbols]

[0253] 1000 patients 1100 Bed Partner 3000 Patient Interface 3100 Seal forming structure 3200 Plenum Chamber Around 3210 3220 Peripheral Edge 3300 Structure 3400 Vent 3402 Outlet orifice 3404 Wall 3406 Diffusion material 3408 Block members 3410 Channel 3412 holes 3414 Center hole 3416 Radial opening 3418 Elbow 3420 Wall 3422 Cap 3424 flange 3426 Annular Gap 3428 Annular groove 3430 Annular protrusion 3432 lips 3434 ball 3436 socket 3438 Snap-on Connection 3440 First Half 3442 Second Half 3500 Separate structure 3500 At least one isolation structure 3600 connection port 3700 forehead support 4000 RPT equipment 4170 Air Circuit 5000 humidifier

Claims

1. 1. A patient interface for sealed delivery of a flow of air at a continuous positive pressure relative to ambient air pressure to an entrance of a patient's airways, the patient interface including at least one nasal entrance of the patient, the patient interface providing a therapeutic pressure of approximately 4 cmH throughout the patient's respiratory cycle while the patient is asleep. ２ Approximately 30cmH from O ２ and configured to maintain a pressure above atmospheric pressure in the range of 0 to 1000 to improve sleep disordered breathing, the patient interface comprising: a sealing structure configured to seal around an entrance to the patient's airway; a positioning and stabilizing structure that maintains the sealing structure in sealing contact with an area surrounding the patient's airway entrance while maintaining a therapeutic pressure at the patient's airway entrance; a plenum chamber configured to be pressurized above ambient pressure in use; a connection port configured to connect the patient interface to an air circuit; CO exhaled by the patient ２ flows outside the plenum chamber, and the CO2 exhaled by the patient ２ a gas scrubbing vent configured to minimize rebreathing of the air, the gas scrubbing vent including at least two exit orifices extending through a wall of the plenum chamber; a diffusing member covering each of said exit orifices; a block member having an air impermeable material; a cap constructed and arranged to cover the diffusing member; Equipped with the at least two outlet orifices are on either side of a central bore of the patient interface, the central bore being configured to allow fluid communication between the plenum chamber and the connection port; the diffusing member includes a first side and a second side opposite the first side across a thickness of the diffusing member; the first side of the diffusing member is constructed and arranged to cover each of the exit orifices such that flow exiting each of the exit orifices impinges on and flows into the diffusing member via the first side; a wall of the plenum chamber in which the at least two exit orifices are formed includes a groove such that a first peripheral region and a second peripheral region of the first side of the diffusion member contact a wall of the plenum chamber, and a central portion of the first side of the diffusion member provided between the first peripheral region and the second peripheral region is spaced from a surface of the wall of the plenum chamber in which the at least two exit orifices are formed; the cap is configured to removably connect to the plenum chamber via a snap-fit ​​connection to allow replacement of the diffusion member; the cap has the block member made of an air-impermeable material; the diffusing member is held by the block member, the blocking member is configured to prevent gas exiting each of the exit orifices from flowing directly through the diffusing member; the block member is constructed and arranged so that gas flows through the diffusing member parallel to a surface of the block member that contacts the diffusing member; 10. A patient interface according to claim 9, wherein the diffusing member is constructed and arranged so that gas exits the diffusing member radially outward through the central hole.

2. 10. The patient interface of claim 1, wherein the diffusion member is a porous material.

3. 10. A patient interface according to claim 1, wherein the diffusion member is an open cell foam.

4. 10. A patient interface according to claim 1, wherein the diffusion member is a fibrous material.

5. A patient interface according to claim 1 , wherein the blocking member is not fixed to the diffusing member.

6. A patient interface according to any preceding claim, wherein a surface of the block member faces each of the exit orifices relative to a thickness of the diffusion member.

7. A patient interface according to any preceding claim, wherein an axis defined by the centre of each of the exit orifices is not perpendicular to the nearest surface of the diffusing member.

8. A patient interface according to any preceding claim, wherein the air impermeable material is a flexible material.

9. A patient interface according to any preceding claim, wherein the air impermeable material is a rigid material.

10. 10. The patient interface of claim 1, wherein at least one of the exit orifices produces choked flow at treatment pressure.

11. At least one of the outlet orifices has a treatment pressure of about 4 cmH ２ 10. The patient interface of claim 1, wherein choked flow occurs when O.

12. To improve sleep disorders while the patient is asleep, the patient's breathing cycle should be maintained at approximately 4 cmH. ２ Approximately 30cmH from O ２ 1. A gas irrigation vent for a patient interface configured to maintain a therapeutic pressure above ambient air pressure in the range of O, the patient interface comprising: a plenum chamber configured to be pressurized above ambient air pressure in use; and a connection port configured to connect the patient interface to an air circuit, the gas irrigation vent comprising: at least two exit orifices through a wall of the plenum chamber, the at least two exit orifices configured to be located on either side of a central hole in the patient interface in use, the central hole configured to allow communication between the plenum chamber and the connection port; a diffusing member covering each of said exit orifices; and a block member having an air impermeable material; a cap constructed and arranged to cover the diffusing member; the diffusing member includes a first side and a second side opposite the first side across a thickness of the diffusing member; the first side of the diffusing member is constructed and arranged to cover each of the exit orifices such that flow exiting each of the exit orifices impinges on and flows into the diffusing member via the first side; a wall of the plenum chamber on which the at least two exit orifices are formed is provided with a groove such that a first peripheral region and a second peripheral region of the first side of the diffusion member contact a wall of the plenum chamber, and a central portion of the first side of the diffusion member provided between the first peripheral region and the second peripheral region is spaced apart from a surface of the wall of the plenum chamber on which the at least two exit orifices are formed; the cap is configured to removably connect to the plenum chamber via a snap-fit ​​connection to allow replacement of the diffusion member; the cap has the block member made of an air-impermeable material; the diffusing member is held by the block member, the blocking member is configured to prevent gas exiting each of the exit orifices from flowing directly through the diffusing member; the block member is constructed and arranged so that gas flows through the diffusing member parallel to a surface of the block member that contacts the diffusing member; 10. A gas washing vent, wherein the diffusion member is constructed and arranged so that gas exits the diffusion member radially outward from the central hole.

13. 13. The gas washing vent of claim 12, wherein the diffusion member is a porous material.

14. 13. The gas washing vent of claim 12, wherein the diffusing member is an open cell foam.

15. 13. The gas washing vent of claim 12, wherein the diffusing member is a fibrous material.

16. 16. The gas cleaning vent of any of claims 12 to 15, wherein the blocking member is not fixed to the diffusing member.

17. 17. The gas washing vent of claim 12, wherein the surface of the block member faces each of the outlet orifices across the thickness of the diffusing member.

18. 18. A gas washing vent according to any one of claims 12 to 17, wherein an axis defined by the centre of each of said exit orifices is not perpendicular to a nearest surface of said diffusing member.

19. 19. A gas cleaning vent according to any one of claims 12 to 18, wherein the air impermeable material is a flexible material.

20. 19. A gas washing vent according to any one of claims 12 to 18, wherein the air impermeable material is a rigid material.

21. 13. The gas washing vent of claim 12, wherein at least one of the exit orifices produces choked flow at the treatment pressure.

22. At least one of the outlet orifices is configured to provide a pressure at which the treatment pressure is about 4 cmH ２ 13. The gas washing vent of claim 12, wherein choked flow occurs when O.

Images