NZ787138A - Patient interface - Google Patents

Abstract

A seal-forming structure (3130) for a patient interface, the seal-forming structure comprising a patient-contacting outer membrane (3139) configured to engage the patient’s facial skin to form a seal with at least one opening (3132) formed through the outer membrane (3139), the opening configured to provide sealed delivery of the flow of air at a continuously positive pressure with respect to ambient air pressure to one or both of the patient’s nares. The seal forming structure includes an undercushion layer (3135) configured to support an inferior portion (3141) against the patient’s lip superior and having alar sealing portion supports (3137) that correspond to two alar sealing portions (3131) in lateral portions (3142) of the seal-forming structure (3130) to support the alar sealing portions (3131) between corresponding ones of the patient’s nasal ala and nasolabial sulcus. A superior portion (3140) of the seal-forming structure is configured to engage the patient’s nose inferior to the patient’s pronasale to form a seal against the patient’s nose proximal to the tip of the patient’s pronasale, the superior portion (3140) not being supported by the undercushion layer and wherein the outer membrane (3139) comprises a thickened region (3134) at each lateral portion (3142) that is thicker than the remainder of the outer membrane (3139).

Description

ResMed Ref: Z3 PATIENT INTERFACE 1 REFERENCE TO RELATED APPLICATIONS The present application claims the benefit of U.S. Provisional ation No. ,988, filed April 28, 2016, and U.S. Provisional Application No. 62/480,059, filed March 31, 2017, the entire contents of each of which is incorporated herein by reference. 2 BACKGROUND OF THE TECHNOLOGY 2.1 FIELD OF THE TECHNOLOGY 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 use. 2.2 DESCRIPTION OF THE RELATED ART 2.2.1 Human Respiratory System and its Disorders The respiratory system of the body facilitates gas exchange. The nose and mouth form the entrance to the airways of a patient.

The airways include a series of branching tubes, which become er, shorter and more numerous as they penetrate deeper into the lung. The prime function of the lung is gas exchange, allowing oxygen to move from the inhaled air into the venous blood and carbon dioxide to move in the opposite direction. The a divides into right and left main bronchi, which r divide eventually into terminal bronchioles. The bronchi make up the conducting airways, and do not take part in gas exchange. Further ons of the s lead to the respiratory bronchioles, and eventually to the alveoli. The alveolated region of the lung is where the gas exchange takes place, and is referred to as the respiratory zone. See "Respiratory Physiology", by John B. West, Lippincott Williams & Wilkins, 9th edition hed 2012.

A range of respiratory disorders exist. Certain disorders may be characterised by particular events, e.g. apneas, hypopneas, and hyperpneas.

ResMed Ref: P1218NZ3 Examples of respiratory disorders include Obstructive Sleep Apnea (OSA), Cheyne-Stokes Respiration (CSR), respiratory insufficiency, Obesity Hyperventilation Syndrome (OHS), Chronic Obstructive Pulmonary Disease (COPD), Neuromuscular Disease (NMD) and Chest wall disorders.

Obstructive Sleep Apnea (OSA), a form of Sleep Disordered Breathing (SDB), is terised by events including occlusion or obstruction of the upper air passage during sleep. It results from a combination of an ally small upper airway and the normal loss of muscle tone in the region of the tongue, soft palate and ior oropharyngeal wall during sleep. The condition causes the affected patient to stop breathing for periods typically of 30 to 120 seconds in duration, sometimes 200 to 300 times per night. It often causes excessive daytime somnolence, and it may cause cardiovascular disease and brain damage. The syndrome is a common disorder, particularly in middle aged ight males, although a person affected may have no awareness of the problem. See US Patent No. 4,944,310 (Sullivan).

Cheyne-Stokes Respiration (CSR) is another form of sleep disordered breathing. CSR is a disorder of a patient's respiratory ller in which there are rhythmic alternating periods of waxing and waning ventilation known as CSR cycles.

CSR is characterised by repetitive de-oxygenation and re-oxygenation of the arterial blood. It is possible that CSR is l because of the repetitive hypoxia. In some ts CSR is ated with repetitive arousal from sleep, which causes severe sleep disruption, increased sympathetic activity, and increased oad. See US Patent No. 6,532,959 (Berthon-Jones).

Respiratory failure is an umbrella term for respiratory disorders in which the lungs are unable to inspire sufficient oxygen or exhale sufficient CO2 to meet the patient’s needs. Respiratory failure may encompass some or all of the following disorders.

A patient with atory insufficiency (a form of atory failure) may experience abnormal shortness of breath on exercise.

ResMed Ref: P1218NZ3 Obesity Hyperventilation Syndrome (OHS) is defined as the ation of severe obesity and awake chronic hypercapnia, in the absence of other known causes for ntilation. Symptoms e dyspnea, morning headache and excessive daytime sleepiness.

Chronic Obstructive ary Disease (COPD) asses any of a group of lower airway es that have certain characteristics in common. These include increased resistance to air movement, extended expiratory phase of respiration, and loss of the normal elasticity of the lung. Examples of COPD are emphysema and chronic bronchitis. COPD is caused by c tobacco smoking (primary risk ), occupational exposures, air pollution and genetic factors.

Symptoms e: dyspnea on exertion, chronic cough and sputum production.

Neuromuscular Disease (NMD) is a broad term that asses many diseases and ailments that impair the functioning of the s either directly via intrinsic muscle pathology, or indirectly via nerve pathology. Some NMD patients are characterised by progressive muscular impairment leading to loss of ambulation, being wheelchair-bound, swallowing difficulties, respiratory muscle weakness and, eventually, death from respiratory failure. Neuromuscular disorders can be divided into rapidly progressive and slowly progressive: (i) y progressive disorders: Characterised by muscle impairment that worsens over months and results in death within a few years (e.g. Amyotrophic l sclerosis (ALS) and ne muscular dystrophy (DMD) in teenagers); (ii) Variable or slowly progressive disorders: Characterised by muscle impairment that worsens over years and only mildly reduces life expectancy (e.g. Limb girdle, Facioscapulohumeral and Myotonic ar dystrophy). Symptoms of respiratory failure in NMD include: increasing generalised weakness, dysphagia, dyspnea on exertion and at rest, fatigue, sleepiness, morning headache, and difficulties with concentration and mood changes.

Chest wall disorders are a group of thoracic deformities that result in inefficient coupling between the respiratory muscles and the thoracic cage. The disorders are usually characterised by a restrictive defect and share the potential of long term hypercapnic respiratory failure. Scoliosis and/or kyphoscoliosis may cause ResMed Ref: P1218NZ3 severe respiratory failure. Symptoms of respiratory failure include: dyspnea on exertion, peripheral oedema, orthopnea, repeated chest infections, morning headaches, fatigue, poor sleep y and loss of te.

A range of therapies have been used to treat or rate such conditions.

Furthermore, otherwise healthy individuals may take age of such therapies to prevent respiratory disorders from arising. However, these have a number of shortcomings. 2.2.2 Therapy Various therapies, such as Continuous Positive Airway Pressure (CPAP) y, Non-invasive ventilation (NIV) and Invasive ventilation (IV) have been used to treat one or more of the above respiratory disorders.

Continuous Positive Airway Pressure (CPAP) therapy has been used to treat Obstructive Sleep Apnea (OSA). The mechanism of action is that continuous positive airway pressure acts as a pneumatic splint and may prevent upper airway occlusion, such as by pushing the soft palate and tongue forward and away from the ior oropharyngeal wall. Treatment of OSA by CPAP therapy may be voluntary, and hence patients may elect not to comply with y if they find devices used to provide such therapy one or more of: uncomfortable, difficult to use, expensive and aesthetically unappealing.

Non-invasive ventilation (NIV) provides ventilatory support to a patient through the upper s to assist the patient breathing and/or maintain adequate oxygen levels in the body by doing some or all of the work of breathing. The ventilatory t is provided via a non-invasive patient interface. NIV has been used to treat CSR and respiratory failure, in forms such as OHS, COPD, NMD and Chest Wall disorders. In some forms, the comfort and effectiveness of these therapies may be improved.

Invasive ventilation (IV) provides ventilatory support to patients that are no longer able to effectively breathe themselves and may be provided using a ResMed Ref: P1218NZ3 tracheostomy tube. In some forms, the comfort and effectiveness of these therapies may be improved. 2.2.3 Treatment Systems These therapies may be provided by a ent system or . Such systems and devices may also be used to diagnose a condition without treating it.

A treatment system may comprise a Respiratory Pressure Therapy Device (RPT device), an air circuit, a humidifier, a patient interface, and data management.

Another form of treatment system is a mandibular repositioning device. 1 Patient ace A patient interface may be used to interface atory equipment to its wearer, for e by providing a flow of air to an entrance to the airways. The flow of air may be provided via a mask to the nose and/or mouth, a tube to the mouth or a tracheostomy tube to the trachea of a patient. Depending upon the therapy to be applied, the patient interface may form a seal, e.g., with a region of the patient's face, to facilitate the ry of gas at a pressure at sufficient variance with ambient pressure to effect therapy, e.g., at a positive pressure of about 10 cmH2O relative to t pressure. For other forms of therapy, such as the delivery of oxygen, the patient interface may not include a seal sufficient to facilitate delivery to the airways of a supply of gas at a positive pressure of about 10 cmH2O.

Certain other mask systems may be functionally able for the present field. For example, purely ornamental masks may be unable to maintain a suitable pressure. Mask systems used for underwater swimming or diving may be configured to guard t ingress of water from an external higher pressure, but not to maintain air internally at a higher re than ambient.

Certain masks may be clinically unfavourable for the present technology e.g. if they block airflow via the nose and only allow it via the mouth.

ResMed Ref: P1218NZ3 Certain masks may be uncomfortable or impractical for the present logy if they require a patient to insert a portion of a mask structure in their mouth to create and maintain a seal via their lips.

Certain masks may be impractical for use while sleeping, e.g. for sleeping while lying on one’s side in bed with a head on a pillow.

The design of a patient interface presents a number of challenges. The face has a complex three-dimensional shape. The size and shape of noses and heads varies considerably between individuals. Since the head includes bone, cartilage and soft tissue, different regions of the face respond differently to mechanical forces. The jaw or mandible may move relative to other bones of the skull. The whole head may move during the course of a period of respiratory therapy.

As a consequence of these challenges, some masks suffer from being one or more of ive, aesthetically undesirable, costly, poorly fitting, difficult to use, and uncomfortable especially when worn for long periods of time or when a patient is unfamiliar with a system. Wrongly sized masks can give rise to reduced compliance, d comfort and poorer patient outcomes. Masks designed solely for aviators, masks designed as part of personal protection equipment (e.g. filter masks), SCUBA masks, or for the stration of anaesthetics may be tolerable for their original ation, but nevertheless such masks may be undesirably uncomfortable to be worn for extended s of time, e.g., several hours. This discomfort may lead to a reduction in patient compliance with therapy. This is even more so if the mask is to be worn during sleep.

CPAP therapy is highly effective to treat certain respiratory disorders, provided patients comply with therapy. If a mask is uncomfortable, or difficult to use a patient may not comply with therapy. Since it is often recommended that a t regularly wash their mask, if a mask is difficult to clean (e.g., ult to assemble or disassemble), patients may not clean their mask and this may impact on patient compliance.

ResMed Ref: Z3 While a mask for other applications (e.g. aviators) may not be suitable for use in treating sleep disordered breathing, a mask ed for use in treating sleep disordered breathing may be suitable for other applications.

For these reasons, patient interfaces for delivery of CPAP during sleep form a distinct field. 2.2.3.1.1 Seal-forming structure t interfaces may include a seal-forming structure. Since it is in direct contact with the patient’s face, the shape and configuration of the orming structure can have a direct impact the effectiveness and comfort of the patient interface.

A patient interface may be partly characterised ing to the design intent of where the seal-forming structure is to engage with the face in use. In one form of patient ace, a seal-forming ure may comprise a first sub-portion to form a seal around the left naris and a second sub-portion to form a seal around the right naris. In one form of patient interface, a seal-forming structure may comprise a single element that surrounds both nares in use. Such single element may be designed to for example overlay an upper lip region and a nasal bridge region of a face. In one form of patient ace a seal-forming structure may comprise an element that surrounds a mouth region in use, e.g. by forming a seal on a lower lip region of a face.

In one form of patient interface, a seal-forming structure may comprise a single element that surrounds both nares and a mouth region in use. These different types of patient interfaces may be known by a variety of names by their manufacturer including nasal masks, full-face masks, nasal pillows, nasal puffs and oro-nasal masks.

A seal-forming structure that may be effective in one region of a patient’s face may be inappropriate in another region, e.g. because of the different shape, structure, variability and sensitivity regions of the patient’s face. For example, a seal on swimming goggles that overlays a patient’s ad may not be appropriate to use on a patient’s nose.

ResMed Ref: P1218NZ3 Certain seal-forming structures may be designed for mass manufacture such that one design fit and be comfortable and effective for a wide range of ent face shapes and sizes. To the extent to which there is a mismatch between the shape of the patient’s face, and the seal-forming structure of the mass-manufactured patient interface, one or both must adapt in order for a seal to form.

One type of orming structure extends around the periphery of the patient interface, and is intended to seal against the patient's face when force is applied to the t interface with the seal-forming structure in confronting engagement with the patient's face. The seal-forming structure may e an air or fluid filled cushion, or a moulded or formed surface of a resilient seal element made of an elastomer such as a rubber. With this type of seal-forming structure, if the fit is not adequate, there will be gaps between the seal-forming structure and the face, and additional force will be required to force the patient interface against the face in order to achieve a seal.

Another type of seal-forming structure incorporates a flap seal of thin material positioned about the periphery of the mask so as to e a self-sealing action against the face of the patient when ve pressure is applied within the mask. Like the previous style of seal forming portion, if the match between the face and the mask is not good, additional force may be required to e a seal, or the mask may leak. Furthermore, if the shape of the orming structure does not match that of the patient, it may crease or buckle in use, giving rise to leaks.

Another type of seal-forming structure may comprise a friction-fit element, e.g. for insertion into a naris, r some patients find these ortable.

Another form of seal-forming structure may use adhesive to achieve a seal. Some patients may find it inconvenient to constantly apply and remove an adhesive to their face.

ResMed Ref: P1218NZ3 A range of patient interface seal-forming structure technologies are disclosed in the following patent applications, assigned to ResMed Limited: WO 04,310; One form of nasal pillow is found in the Adam Circuit manufactured by Puritan t. r nasal pillow, or nasal puff is the subject of US Patent 4,782,832 (Trimble et al.), assigned to Puritan-Bennett ation.

ResMed Limited has manufactured the following products that incorporate nasal pillows: SWIFTTM nasal pillows mask, SWIFTTM II nasal pillows mask, SWIFTTM LT nasal pillows mask, SWIFTTM FX nasal pillows mask and MIRAGE LIBERTYTM full-face mask. The following patent applications, assigned to ResMed Limited, describe examples of nasal pillows masks: International Patent Application WO2004/073,778 (describing amongst other things aspects of the ResMed Limited SWIFTTM nasal pillows), US Patent ation 044808 (describing amongst other things aspects of the ResMed Limited SWIFTTM LT nasal pillows); International Patent Applications (describing amongst other things aspects of the ResMed Limited MIRAGE LIBERTYTM full-face mask); International Patent Application (describing amongst other things aspects of the ResMed Limited SWIFTTM FX nasal pillows). 1.2 Positioning and stabilising A seal-forming structure of a patient interface used for positive air pressure therapy is subject to the corresponding force of the air pressure to t a seal. Thus a variety of techniques have been used to position the seal-forming structure, and to maintain it in sealing relation with the riate portion of the face.

One technique is the use of adhesives. See for e US Patent Application Publication No. US 2010/0000534. However, the use of ves may be uncomfortable for some.

ResMed Ref: P1218NZ3 Another que is the use of one or more straps and/or stabilising harnesses. Many such harnesses suffer from being one or more of ill-fitting, bulky, ortable and d to use. 2 Respiratory Pressure Therapy (RPT) Device A respiratory pressure therapy (RPT) device may be used to deliver one or more of a number of therapies described above, such as by generating a flow of air for delivery to an entrance to the airways. The flow of air may be pressurised. Examples of RPT devices include a CPAP device and a ventilator.

Air pressure tors are known in a range of applications, e.g. industrial-scale ventilation systems. However, air pressure generators for medical applications have particular requirements not fulfilled by more generalised air pressure generators, such as the reliability, size and weight requirements of medical devices. In addition, even devices designed for medical ent may suffer from omings, pertaining to one or more of: t, noise, ease of use, efficacy, size, weight, manufacturability, cost, and reliability.

An example of the special requirements of certain RPT devices is acoustic noise.

Table of noise output levels of prior RPT devices (one specimen only, measured using test method specified in ISO 3744 in CPAP mode at 10 cmH2O).

RPT Device name A-weighted sound Year (approx.) pressure level dB(A) C-Series TangoTM 31.9 2007 C-Series TangoTM with Humidifier 33.1 2007 S8 EscapeTM II 30.5 2005 S8 EscapeTM II with H4iTM Humidifier 31.1 2005 S9 AutoSetTM 26.5 2010 S9 AutoSetTM with H5i Humidifier 28.6 2010 ResMed Ref: P1218NZ3 One known RPT device used for ng sleep disordered breathing is the S9 Sleep y System, manufactured by ResMed Limited. Another example of an RPT device is a ventilator. Ventilators such as the ResMed Stellar™ Series of Adult and Paediatric Ventilators may provide support for invasive and non-invasive nondependent ventilation for a range of patients for treating a number of conditions such as but not limited to NMD, OHS and COPD.

The ResMed Elisée™ 150 ventilator and ResMed VS III™ ventilator may provide t for invasive and non-invasive dependent ventilation suitable for adult or paediatric patients for treating a number of conditions. These ventilators provide volumetric and barometric ventilation modes with a single or double limb circuit.

RPT devices typically comprise a pressure generator, such as a motor-driven blower or a compressed gas reservoir, and are configured to supply a flow of air to the airway of a patient. In some cases, the flow of air may be supplied to the airway of the patient at positive pressure. The outlet of the RPT device is connected via an air circuit to a patient ace such as those bed above.

The designer of a device may be presented with an infinite number of choices to make. Design criteria often conflict, meaning that certain design choices are far from routine or able. Furthermore, the comfort and efficacy of certain aspects may be highly sensitive to small, subtle changes in one or more parameters. 2.2.3.3 Humidifier Delivery of a flow of air without humidification may cause drying of airways. The use of a humidifier with an RPT device and the patient ace produces humidified gas that minimizes drying of the nasal mucosa and increases patient airway comfort. In addition in cooler climates, warm air applied generally to the face area in and about the t interface is more comfortable than cold air.

A range of artificial fication s and systems are known, however they may not fulfil the lised requirements of a medical humidifier.

Medical humidifiers are used to increase humidity and/or temperature of the flow of air in relation to ambient air when required, typically where the patient ResMed Ref: Z3 may be asleep or resting (e.g. at a hospital). A medical humidifier for bedside placement may be small. A medical humidifier may be configured to only humidify and/or heat the flow of air delivered to the patient without humidifying and/or heating the patient’s surroundings. Room-based systems (e.g. a sauna, an air conditioner, or an evaporative cooler), for example, may also humidify air that is breathed in by the patient, however those systems would also humidify and/or heat the entire room, which may cause discomfort to the occupants. Furthermore medical humidifiers may have more stringent safety constraints than industrial humidifiers While a number of medical humidifiers are known, they can suffer from one or more shortcomings. Some medical humidifiers may provide uate humidification, some are difficult or inconvenient to use by patients. 2.2.3.4 Data ment There may be al reasons to obtain data to determine whether the patient prescribed with respiratory therapy has been "compliant", e.g. that the patient has used their RPT device according to certain a "compliance rule". One example of a ance rule for CPAP therapy is that a patient, in order to be deemed compliant, is required to use the RPT device for at least four hours a night for at least 21 of 30 utive days. In order to determine a t's compliance, a provider of the RPT device, such as a health care provider, may manually obtain data describing the patient's therapy using the RPT device, calculate the usage over a ermined time period, and compare with the compliance rule. Once the health care provider has determined that the patient has used their RPT device according to the compliance rule, the health care provider may notify a third party that the patient is compliant.

There may be other aspects of a patient’s therapy that would benefit from communication of therapy data to a third party or external .

Existing processes to communicate and manage such data can be one or more of , onsuming, and error-prone.

ResMed Ref: P1218NZ3 2.2.3.5 Mandibular repositioning A mandibular repositioning device (MRD) or mandibular advancement device (MAD) is one of the treatment options for sleep apnea and snoring. It is an adjustable oral appliance available from a dentist or other supplier that holds the lower jaw (mandible) in a forward position during sleep. The MRD is a removable device that a patient s into their mouth prior to going to sleep and removes following sleep. Thus, the MRD is not ed to be worn all of the time. The MRD may be custom made or produced in a standard form and includes a bite sion portion designed to allow g to a patient’s teeth. This mechanical protrusion of the lower jaw expands the space behind the tongue, puts tension on the pharyngeal walls to reduce collapse of the airway and diminishes palate vibration.

In certain examples a mandibular advancement device may comprise an upper splint that is intended to engage with or fit over teeth on the upper jaw or maxilla and a lower splint that is intended to engage with or fit over teeth on the upper jaw or le. The upper and lower splints are connected together laterally via a pair of connecting rods. The pair of connecting rods are fixed symmetrically on the upper splint and on the lower .

In such a design the length of the connecting rods is selected such that when the MRD is placed in a patient’s mouth the mandible is held in an advanced position. The length of the ting rods may be ed to change the level of protrusion of the mandible. A dentist may determine a level of protrusion for the mandible that will determine the length of the connecting rods.

Some MRDs are structured to push the mandible forward relative to the maxilla while other MADs, such as the ResMed Narval CC™ MRD are designed to retain the mandible in a forward position. This device also reduces or minimises dental and temporo-mandibular joint (TMJ) side s. Thus, it is configured to minimises or prevent any movement of one or more of the teeth.

ResMed Ref: P1218NZ3 2.2.3.6 Vent technologies Some forms of treatment systems may include a vent to allow the washout of exhaled carbon dioxide. The vent may allow a flow of gas from an interior space of a patient interface, e.g., the plenum chamber, to an exterior of the patient interface, e.g., to ambient.

The vent may comprise an orifice and gas may flow through the orifice in use of the mask. Many such vents are noisy. Others may become d in use and thus provide insufficient washout. Some vents may be disruptive of the sleep of a bed partner 1100 of the patient 1000, e.g. h noise or focussed airflow.

ResMed Limited has ped a number of improved mask vent technologies. See International Patent Application Publication No.

International Patent Application Publication No. 594; US Patent Application Publication No. US 2009/0050156; US Patent Application Publication No. 2009/0044808.

Table of noise of prior masks (ISO 17510-2:2007, 10 cmH2O pressure at Mask name Mask type A-weighted A-weighted Year (approx.) sound power sound pressure level dB(A) dB(A) (uncertainty) (uncertainty) n (*) nasal 50.9 42.9 1981 ResCare nasal 31.5 23.5 1993 standard (*) ResMed nasal 29.5 21.5 1998 MirageTM (*) ResMed nasal 36 (3) 28 (3) 2000 UltraMirageTM ResMed nasal 32 (3) 24 (3) 2002 Mirage ResMed nasal 30 (3) 22 (3) 2008 Mirage MicroTM ResMed Ref: P1218NZ3 ResMed nasal 29 (3) 22 (3) 2008 MirageTM SoftGel ResMed nasal 26 (3) 18 (3) 2010 TM FX ResMed nasal s 37 29 2004 Mirage SwiftTM ResMed nasal pillows 28 (3) 20 (3) 2005 Mirage SwiftTM ResMed nasal pillows 25 (3) 17 (3) 2008 Mirage SwiftTM ResMed AirFit nasal pillows 21 (3) 13 (3) 2014 (* one en only, measured using test method specified in ISO 3744 in CPAP mode at 10 cmH2O) Sound pressure values of a variety of objects are listed below Object A-weighted sound pressure dB(A) Notes Vacuum cleaner: Nilfisk 68 ISO 3744 at 1m Walter Broadly Litter Hog: B+ distance Grade Conversational speech 60 1m distance Average home 50 Quiet library 40 Quiet bedroom at night 30 ound in TV studio 20 2.2.4 Diagnosis and Monitoring Systems Polysomnography (PSG) is a conventional system for diagnosis and monitoring of cardio-pulmonary disorders, and typically involves expert clinical staff to apply the system. PSG typically involves the placement of 15 to 20 contact sensors ResMed Ref: P1218NZ3 on a patient in order to record various bodily signals such as oencephalography (EEG), electrocardiography (ECG), electrooculograpy (EOG), electromyography (EMG), etc. PSG for sleep disordered ing has involved two nights of observation of a patient in a clinic, one night of pure diagnosis and a second night of titration of treatment parameters by a clinician. PSG is therefore expensive and inconvenient. In particular it is unsuitable for home sleep testing.

Clinical experts may be able to diagnose or monitor patients adequately based on visual observation of PSG s. However, there are circumstances where a clinical expert may not be available, or a clinical expert may not be affordable.

Different al s may disagree on a patient’s condition. In addition, a given clinical expert may apply a different standard at different times. 3 BRIEF SUMMARY OF THE TECHNOLOGY The present technology is directed towards providing medical devices used in the diagnosis, amelioration, treatment, or prevention of respiratory disorders having one or more of ed comfort, cost, efficacy, ease of use and manufacturability.

A first aspect of the present technology relates to apparatus used in the diagnosis, amelioration, treatment or tion of a atory disorder.

Another aspect of the present logy relates to methods used in the diagnosis, amelioration, treatment or prevention of a respiratory er.

An aspect of certain forms of the present technology is to provide methods and/or apparatus that improve the compliance of patients with respiratory therapy.

An aspect of the present technology is directed to a seal-forming structure for a patient interface that is configured to form a seal with the patient’s nares and the seal-forming structure comprises a support structure forming a continuous loop with an interior surface of the orming structure, the loop structure supporting a superior portion of a patient contacting surface of the orming structure, and the ResMed Ref: P1218NZ3 superior portion of the patient contacting surface having a single layer that is not supported by an undercushion.

An aspect of the present technology is ed to a patient interface that comprises: a plenum chamber pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum r including a plenum chamber inlet port sized and structured to e a flow of air at the therapeutic pressure for breathing by a patient, a seal-forming structure constructed and arranged to form a seal with a region of the patient’s face nding an ce to the patient’s s, the seal-forming ure ucted and arranged to maintain said therapeutic pressure in the plenum chamber throughout the patient’s respiratory cycle in use; a positioning and stabilising structure to provide a force to hold the sealforming structure in a therapeutically effective position on the patient’s head, the positioning and stabilising structure comprising a tie, the tie being ucted and arranged so that at least a portion overlies a region of the patient’s head or to an otobasion superior of the patient’s head in use; and a vent structure to allow a continuous flow of gases exhaled by the patient from an interior of the plenum chamber to ambient, said vent structure being sized and shaped to maintain the therapeutic pressure in the plenum r in use, n the patient interface is configured to allow the t to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient interface is configured to leave the t’s mouth uncovered, wherein the seal-forming structure further comprises a patient-contacting surface configured to engage the patient’s facial skin to form a seal and a posterior opening formed in the patient-contacting surface, the posterior opening configured to provide the flow of air at said therapeutic pressure to the patient’s nares, and wherein the seal-forming structure includes a support structure extending from the patient contacting surface to an interior surface of the seal-forming structure, the support structure and the interior surface forming a continuous loop.

In examples, (a) the orming structure may comprise an anterior opening formed in a non-patient contacting surface and an anterior tie that spans the anterior opening, and a first end of the support structure may be connected to the ResMed Ref: P1218NZ3 anterior tie, (b) the seal-forming structure may comprise an edge bounding the ior opening in the patient contacting e, and a second end of the support structure may be connected to the patient contacting surface at a superior region of the edge, (c) the seal-forming structure may comprise an undercushion that supports the patient contacting surface, (d) an inferior n of the seal-forming structure may include the undercushion and a superior portion of the seal-forming structure may not include the undercushion, and/or (e) the undercushion may be structured to only support the patient contacting surface against the patient’s lip superior.

An aspect of the present technology is directed to a seal-forming structure for a t interface, the seal-forming structure constructed and ed to form a seal with a region of the patient’s face nding an entrance to the patient’s airways, the seal-forming structure constructed and arranged to maintain a eutic pressure of at least 6 cmH2O above ambient air pressure in a plenum chamber hout the patient’s respiratory cycle in use. The seal-forming structure comprises: a patient-contacting surface configured to engage the patient’s facial skin to form a seal; a posterior opening formed in the patient-contacting surface, the posterior opening configured to provide the flow of air at said therapeutic re to the patient’s nares; and a support ure extending from the t contacting surface to an interior surface of the seal-forming structure, the support structure and the interior surface forming a continuous loop, wherein the patient interface is configured to allow the patient to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum r inlet port, or the patient interface is configured to leave the patient’s mouth uncovered.

In examples, (a) the seal-forming structure may se an anterior opening formed in a non-patient contacting surface and an anterior tie that spans the anterior opening, and a first end of the support structure may be ted to the anterior tie, (b) the seal-forming structure may comprise an edge bounding the posterior opening in the patient contacting surface, and a second end of the t structure may be connected to the patient contacting surface at a superior region of the edge, (c) the seal-forming ure may comprise an undercushion that supports the patient contacting surface, (d) an inferior n of the seal-forming structure may ResMed Ref: P1218NZ3 include the ushion and a superior portion of the seal-forming structure may not include the undercushion, and/or (e) the undercushion may be structured to only t the patient contacting surface t the patient’s lip superior.

Another aspect of the present technology is directed to a t ace for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to the patient’s airways including at least an entrance of a t’s nares, wherein the patient interface is ured to in a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the patient’s respiratory cycle, while the patient is ng, to ameliorate sleep disordered breathing. The patient interface may comprise: a seal forming structure to form a seal with the entrance to the patient’s airways including at least the entrance of the patient’s nares; a plenum chamber pressurised at a pressure above ambient pressure in use, the seal g structure attached to the plenum chamber; and a positioning and stabilising structure to maintain the seal forming structure in g contact with an area surrounding the entrance to the patient’s airways while maintaining a therapeutic pressure at the entrance to the patient’s airways, wherein the positioning and stabilising structure is connected to the plenum chamber such that forces imposed on the oning and stabilising structure by movement of the patient’s head are decoupled from the plenum chamber and the seal forming structure.

In examples, (a) the positioning and stabilising structure may comprise a rigidiser arm assembly, the rigidiser arm assembly being flexibly attached to the plenum chamber, (b) the rigidiser arm assembly may be flexibly attached to the plenum chamber such that in use the rigidiser arm ly is e substantially independently relative to the plenum chamber and the seal forming structure, (c) the rigidiser arm assembly may be flexibly attached to the plenum chamber such that movement of the positioning and stabilising structure in use does not disrupt the g contact of the seal forming structure with the area surrounding the entrance to the patient’s airways, (d) the rigidiser arm assembly may be ly attached to a medial, anterior surface of the plenum chamber, (e) the rigidiser arm assembly may be flexibly attached to the plenum chamber with an elastic material, (f) the positioning ResMed Ref: P1218NZ3 and stabilising structure may comprise a plurality of straps to secure the patient interface on the patient’s head in use by attachment to the rigidiser arm assembly, (g) the plurality of straps may be only connected to the rigidiser arm assembly, (h) the ser arm assembly may comprise two rigider arms, each of the rigidiser arms configured to pass along one of the patient’s cheeks in use, and each of the ser arms having an opening, (i) the plurality of straps may comprise two side straps, each of the side straps configured to connect to one of the rigidiser arms at the opening, and each of the side straps configured to pass below the patient’s eye and above the patient’s ear in use, (j) each of the side straps may e one of a hook al and a loop material and each of the side straps may include a connector of the other of the hook material and the loop material to secure the side straps to the rigidiser arms through each opening, (k) a first strap of the plurality of straps may be made of a first material having a first elasticity and a second strap of the plurality of straps may be made of a second material having a second city that is different from the first elasticity, (l) each of first material and the second material may be one of textile, foam, and breathable neoprene, (m) the plurality of straps may comprise a crown strap to engage the patient’s head proximal to the al bone and a rear strap to engage the patient’s head proximal to the occipital bone, (l) the rear strap may be more elastic than the crown strap, (m) the seal forming ure may have one opening to e the pressurised gas to both of the patient’s nares or the seal forming ure may have two openings such that each of the two gs provide the pressurised gas to a corresponding one of the t’s nares, (n) the seal g structure may include two alar sealing portions, each alar sealing portion being shaped and dimensioned to seal between corresponding ones of the patient’s nasal ala and nasolabial sulcus, (o) the seal forming structure may include an undercushion shaped and dimensioned to only support an inferior portion of the seal forming structure against the patient’s lip superior and the alar sealing portions against corresponding ones of the patient’s nasal ala and nasolabial sulcus, (p) the seal forming structure and the undercushion may be formed from one homogeneous piece of material, and/or (q) the seal forming structure and the undercushion may be formed from silicone. r aspect of the present technology may be directed to a patient interface for sealed delivery of a flow of air at a continuously positive pressure with ResMed Ref: P1218NZ3 respect to ambient air pressure to an entrance to the patient’s airways including at least an entrance of a patient’s nares, wherein the patient ace is configured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the patient’s respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing. The patient interface may comprise: a seal forming structure to form a seal with the entrance to the patient’s airways including at least the entrance of the patient’s nares; a plenum r pressurised at a pressure above ambient pressure in use, the seal g structure attached to the plenum chamber; and a positioning and stabilising structure to maintain the seal forming structure in sealing contact with an area surrounding the entrance to the patient’s airways while ining a therapeutic pressure at the entrance to the patient’s airways, wherein the positioning and stabilising structure comprises a rigidiser arm assembly that is ly connected to the plenum chamber by at least one flexible ling structure such that forces imposed on the positioning and stabilising structure by movement of the t’s head are led from the plenum chamber and the seal forming structure.

In es, (a) the plenum chamber may comprise a plenum chamber connector and the rigidiser arm assembly may se a rigidiser arm connection ring, and the plenum chamber connector and the rigidiser arm connection ring may be flexibly connected by the at least one flexible decoupling structure, wherein the plenum chamber connector is fixed to a medial, anterior surface of the plenum chamber, (b) the rigidiser arm ly may comprise two r arms, each of the rigidiser arms configured to pass along one of the patient’s cheeks in use, and the rigidiser arm ly may se two rigidiser arm connectors, each of the rigidiser arm connectors connecting a corresponding rigidiser arm to the rigidiser arm connection ring, (c) the rigidiser arm connection ring and the two rigidiser arm connectors may be formed from one homogeneous piece of a first material, (d) each of the rigidiser arms may be formed from a second material that is different from the first material, (e) the first material may be more rigid than the second material, (f) each of the rigidiser arms may be connected to a corresponding one of the rigidiser arm connectors with a chemical bond or a mechanical interlock, (g) the at least one flexible decoupling ure may comprise an elastic material, (h) the positioning and ResMed Ref: P1218NZ3 stabilising structure may comprise a plurality of straps to secure the patient interface on the patient’s head in use by ment to the rigidiser arm assembly, (i) the plurality of straps may be only connected to the rigidiser arm assembly, (j) each of the rigidiser arms may have an opening, and the plurality of straps may se two side straps, each of the side straps configured to connect to one of the rigidiser arms at the opening, and each of the side straps configured to pass below the t’s eye and above the patient’s ear in use, (k) each of the side straps may include one of a hook material and a loop material and each of the side straps may include a connector of the other of the hook material and the loop material to secure the side straps to the rigidiser arms through each opening, (l) a first strap of the plurality of straps may be made of a first material having a first elasticity and a second strap of the plurality of straps may be made of a second material having a second elasticity that is different from the first elasticity, (m) each of first material and the second al may be one of e, foam, and breathable neoprene, (n) the plurality of straps may comprise a crown strap to engage the patient’s head proximal to the parietal bone and a rear strap to engage the t’s head proximal to the occipital bone, (o) the rear strap may be more elastic than the crown strap, (p) the seal g structure may have one opening to provide the pressurised gas to both of the patient’s nares or the seal g ure may have two gs such that each of the two openings provide the pressurised gas to a corresponding one of the patient’s nares, (q) the seal forming structure may e two alar sealing portions, each alar sealing portion being shaped and dimensioned to seal between corresponding ones of the patient’s nasal ala and nasolabial sulcus, (r) the seal forming structure may include an undercushion shaped and dimensioned to only support an inferior portion of the seal forming structure against the patient’s lip superior and the alar sealing portions against corresponding ones of the patient’s nasal ala and nasolabial sulcus, (s) the seal forming structure and the undercushion may be formed from one homogeneous piece of material, and/or (t) the seal forming structure and the undercushion are formed from silicone.

Another aspect of the t technology is directed to a seal-forming structure for a patient interface configured to provide sealed delivery of a flow of air at a continuously ve pressure with respect to ambient air pressure to an entrance to the patient’s airways including at least an entrance of a patient’s nares, wherein the ResMed Ref: P1218NZ3 t interface is ured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the patient’s respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing. The seal-forming structure may comprise: an outer membrane configured to form a seal with the inferior periphery of the patient’s nose, the outer membrane having an inferior portion to form a seal with the patient’s lip superior, and the outer membrane having two alar sealing portions, each alar sealing portion being shaped and dimensioned to seal between corresponding ones of the patient’s nasal ala and nasolabial sulcus; at least one opening formed through the outer membrane to e sealed delivery of the flow of air at the uously positive pressure with respect to t air re to one or both of the patient’s nares; an undercushion to support the inferior portion against the patient’s lip superior and having alar sealing portion supports that pond to each of the alar sealing portions to support the alar sealing portions between corresponding ones of the patient’s nasal ala and bial sulcus.

In examples, (a) the undercushion layer may extend partially around the periphery of the outer membrane, (b) the ushion layer may terminate at each lateral side at the alar sealing portion supports, (c) the seal-forming structure may comprise a or portion to form a seal proximal to the tip of the patient’s nose, the superior portion not being supported by the undercushion layer, (d) in use the sealforming structure may not extend beyond the patient’s septal age, (e) in use the seal-forming structure may not extend beyond the patient’s alar cartilage, (f) the sealforming structure may comprise a lateral portion on each lateral side of the seal- forming structure to form a seal with a corresponding ala of the patient’s nose, (g) the outer membrane may comprise a thickened region at each lateral portion that is thicker than the remainder of the outer membrane, (h) the seal-forming structure may comprise one opening formed through the outer membrane to provide sealed ry of the flow of air at the continuously positive pressure with t to ambient air pressure to both of the patient’s nares, and/or (i) the seal-forming structure may comprise two openings formed through the outer membrane to e sealed ry of the flow of air at the continuously positive pressure with respect to ambient air pressure to a corresponding one of the patient’s nares and a columella ResMed Ref: P1218NZ3 engagement portion between the openings to engage the columella of the patient’s nose. r aspect of the present technology is directed to a patient interface for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to the patient’s airways including at least an ce of a patient’s nares, wherein the patient interface is configured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the patient’s respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing. The t interface may se: a plenum chamber pressurised at a pressure above ambient pressure in use; the seal forming structure including one or more of the features bed in the two preceding paragraphs, the seal forming structure having a plenum chamber connection portion attached to the plenum chamber; and a positioning and stabilising structure to maintain the seal forming structure in g contact with an area surrounding the entrance to the patient’s airways while maintaining a therapeutic pressure at the entrance to the patient’s airways. r aspect of one form of the present technology is a patient interface that is moulded or otherwise constructed with a perimeter shape which is complementary to that of an intended wearer.

An aspect of one form of the t technology is a method of manufacturing apparatus.

An aspect of certain forms of the t technology is a medical device that is easy to use, e.g. by a person who does not have l training, by a person who has limited dexterity, vision or by a person with d experience in using this type of medical device.

An aspect of one form of the present technology is a patient interface that may be washed in a home of a patient, e.g., in soapy water, without ing specialised cleaning equipment. An aspect of one form of the present technology is a ResMed Ref: Z3 humidifier tank that may be washed in a home of a patient, e.g., in soapy water, without requiring specialised cleaning equipment.

Of course, portions of the aspects may form sub-aspects of the present logy. Also, various ones of the sub-aspects and/or aspects may be combined in various manners and also constitute additional s or sub-aspects of the present technology.

Other features of the technology will be apparent from consideration of the information contained in the following detailed description, abstract, drawings and claims. 4 BRIEF DESCRIPTION OF THE DRAWINGS The present technology is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to similar elements including: 4.1 TREATMENT SYSTEMS Fig. 1A shows a system including a patient 1000 wearing a patient interface 3000, in the form of nasal pillows, receiving a supply of air at ve pressure from an RPT device 4000. Air from the RPT device 4000 is humidified in a humidifier 5000, and passes along an air circuit 4170 to the t 1000. A bed partner 1100 is also shown. The patient is sleeping in a supine sleeping on.

Fig. 1B shows a system including a t 1000 wearing a patient interface 3000, in the form of a nasal mask, receiving a supply of air at positive pressure from an RPT device 4000. Air from the RPT device is humidified in a humidifier 5000, and passes along an air circuit 4170 to the patient 1000.

Fig. 1C shows a system including a t 1000 wearing a patient interface 3000, in the form of a full-face mask, receiving a supply of air at positive pressure from an RPT device 4000. Air from the RPT device is humidified in a humidifier 5000, and passes along an air t 4170 to the patient 1000. The t is sleeping in a side sleeping position.

ResMed Ref: P1218NZ3 4.2 RESPIRATORY SYSTEM AND FACIAL ANATOMY Fig. 2A shows an overview of a human respiratory system including the nasal and oral cavities, the larynx, vocal folds, oesophagus, trachea, bronchus, lung, alveolar sacs, heart and diaphragm.

Fig. 2B shows a view of a human upper airway including the nasal cavity, nasal bone, lateral nasal cartilage, greater alar cartilage, nostril, lip superior, lip inferior, larynx, hard palate, soft palate, oropharynx, tongue, epiglottis, vocal folds, oesophagus and trachea.

Fig. 2C is a front view of a face with l features of surface anatomy identified including the lip superior, upper ion, lower vermilion, lip inferior, mouth width, endocanthion, a nasal ala, nasolabial sulcus and on. Also indicated are the directions superior, or, radially inward and radially outward.

Fig. 2D is a side view of a head with several features of e anatomy identified including glabella, sellion, pronasale, subnasale, lip or, lip inferior, supramenton, nasal ridge, alar crest point, otobasion superior and otobasion inferior.

Also indicated are the directions or & inferior, and anterior & posterior.

Fig. 2E is a further side view of a head. The approximate locations of the Frankfort horizontal and nasolabial angle are indicated. The coronal plane is also indicated.

Fig. 2F shows a base view of a nose with several features identified including naso-labial sulcus, lip inferior, upper Vermilion, naris, subnasale, columella, ale, the major axis of a naris and the midsagittal plane.

Fig. 2G shows a side view of the superficial features of a nose.

Fig. 2H shows subcutaneal structures of the nose, ing lateral cartilage, septum cartilage, greater alar cartilage, lesser alar age, id cartilage, nasal bone, epidermis, adipose tissue, frontal process of the maxilla and fibrofatty tissue.

ResMed Ref: P1218NZ3 Fig. 2I shows a medial dissection of a nose, approximately l millimeters from the midsagittal plane, amongst other things showing the septum cartilage and medial crus of greater alar age.

Fig. 2J shows a front view of the bones of a skull including the frontal, nasal and zygomatic bones. Nasal concha are indicated, as are the maxilla, and mandible.

Fig. 2K shows a lateral view of a skull with the outline of the surface of a head, as well as several muscles. The ing bones are shown: frontal, sphenoid, nasal, zygomatic, maxilla, mandible, parietal, temporal and occipital. The mental protuberance is indicated. The following muscles are shown: digastricus, masseter, sternocleidomastoid and trapezius.

Fig. 2L shows an anterolateral view of a nose. 4.3 PATIENT INTERFACE Fig. 3A shows a patient interface in the form of a nasal mask in accordance with one form of the present technology.

Fig. 3B shows a schematic of a cross-section through a structure at a point. An outward normal at the point is ted. The curvature at the point has a ve sign, and a relatively large magnitude when compared to the ude of the curvature shown in Fig. 3C.

Fig. 3C shows a tic of a cross-section through a structure at a point. An outward normal at the point is indicated. The curvature at the point has a ve sign, and a relatively small magnitude when compared to the magnitude of the curvature shown in Fig. 3B.

Fig. 3D shows a schematic of a cross-section through a structure at a point. An outward normal at the point is indicated. The curvature at the point has a value of zero.

ResMed Ref: P1218NZ3 Fig. 3E shows a schematic of a cross-section through a structure at a point. An outward normal at the point is indicated. The curvature at the point has a negative sign, and a relatively small magnitude when compared to the magnitude of the ure shown in Fig. 3F.

Fig. 3F shows a schematic of a cross-section through a structure at a point.

An outward normal at the point is indicated. The curvature at the point has a ve sign, and a relatively large magnitude when compared to the magnitude of the ure shown in Fig. 3E.

Fig. 3G shows a cushion for a mask that includes two pillows. An exterior surface of the n is indicated. An edge of the surface is indicated. Dome and saddle regions are ted.

Fig. 3H shows a cushion for a mask. An exterior surface of the cushion is indicated. An edge of the surface is indicated. A path on the surface n points A and B is indicated. A straight line distance between A and B is indicated. Two saddle regions and a dome region are indicated.

Fig. 3I shows the surface of a structure, with a one dimensional hole in the surface. The illustrated plane curve forms the boundary of a one dimensional hole.

Fig. 3J shows a cross-section through the structure of Fig.3I. The illustrated surface bounds a two dimensional hole in the structure of Fig. 3I.

Fig. 3K shows a perspective view of the structure of Fig. 3I, including the two dimensional hole and the one dimensional hole. Also shown is the surface that bounds a two dimensional hole in the structure of Fig. 3I.

Fig. 3L shows a mask having an inflatable bladder as a cushion.

Fig. 3M shows a cross-section h the mask of Fig. 3L, and shows the interior surface of the bladder. The interior e bounds the two dimensional hole in the mask.

ResMed Ref: P1218NZ3 Fig. 3N shows a further cross-section through the mask of Fig. 3L. The interior surface is also indicated.

Fig. 3O illustrates a left-hand rule.

Fig. 3P illustrates a right-hand rule.

Fig. 3Q shows a left ear, including the left ear helix.

Fig. 3R shows a right ear, including the right ear helix.

Fig. 3S shows a right-hand helix.

Fig. 3T shows a view of a mask, including the sign of the torsion of the space curve defined by the edge of the sealing membrane in different regions of the mask.

Fig. 3U shows a view of a plenum chamber (cushion assembly) 3200 showing a sagittal plane and a mid-contact plane.

Fig. 3V shows a view of a ior of the plenum chamber of Fig. 3U.

The direction of the view is normal to the mid-contact plane. The sagittal plane in Fig. 3V bisects the plenum chamber into left-hand and right-hand sides.

Fig. 3W shows a cross-section through the plenum chamber of Fig. 3V, the section being taken at the sagittal plane shown in Fig. 3V. A ‘mid-contact’ plane is shown. The mid-contact plane is perpendicular to the sagittal plane. The orientation of the mid-contact plane corresponds to the ation of a chord 3210 which lies on the sagittal plane and just s the cushion of the plenum chamber at two points on the sagittal plane: a or point 3220 and an inferior point 3230.

Depending on the ry of the cushion in this , the mid-contact plane may be a tangent at both the superior and inferior points.

Fig. 3X shows the plenum chamber 3200 of Fig. 3U in position for use on a face. The sagittal plane of the plenum chamber 3200 generally coincides with the midsagittal plane of the face when the plenum chamber is in position for use. The ResMed Ref: P1218NZ3 mid-contact plane corresponds generally to the ‘plane of the face’ when the plenum chamber is in position for use. In Fig. 3X the plenum chamber 3200 is that of a nasal mask, and the superior point 3220 sits approximately on the sellion, while the inferior point 3230 sits on the lip superior. 4.4 RPT DEVICE Fig. 4A shows an RPT device in accordance with one form of the present technology.

Fig. 4B is a schematic diagram of the tic path of an RPT device in accordance with one form of the present technology. The directions of upstream and downstream are indicated with reference to the blower and the patient interface. The blower is defined to be upstream of the patient interface and the patient interface is defined to be downstream of the blower, regardless of the actual flow direction at any ular moment. Items which are located within the tic path between the blower and the patient interface are downstream of the blower and upstream of the patient interface. 4.5 HUMIDIFIER Fig. 5A shows an isometric view of a humidifier in accordance with one form of the present technology.

Fig. 5B shows an isometric view of a humidifier in accordance with one form of the t technology, showing a humidifier reservoir 5110 removed from the humidifier reservoir dock 5130. 4.6 BREATHING RMS Fig. 6 shows a model typical breath waveform of a person while sleeping. 4.7 PATIENT INTERFACE ACCORDING TO THE PRESENT TECHNOLOGY depicts an anterior perspective view of a orming structure of a t interface according to an e of the present technology.

ResMed Ref: P1218NZ3 s an anterior view of a seal-forming structure of a patient interface according to an example of the t technology. s a lateral view of a seal-forming structure of a patient interface according to an example of the present technology. depicts a posterior view of a seal-forming structure of a patient interface according to an example of the present technology. depicts an inferior view of a seal-forming ure of a patient ace according to an example of the present technology. depicts a superior view of a seal-forming structure of a t interface according to an e of the present technology. depicts a cross-sectional view of a seal-forming structure of a patient interface taken through line 7G-7G of according to an example of the present technology. depicts a cross-sectional view of a seal-forming structure of a t interface taken through line 7H-7H of according to an example of the present technology. depicts a cross-sectional view of a seal-forming structure of a patient interface taken through line 7I-7I of according to an example of the present technology. depicts a cross-sectional view of a seal-forming ure of a patient interface taken through line 7J-7J of according to an example of the present technology. s a cross-sectional view of a seal-forming structure of a patient interface taken through line 7K-7K of according to an example of the present technology.

ResMed Ref: P1218NZ3 depicts a cross-sectional view of a seal-forming structure of a patient interface taken through line 7L-7L of according to an example of the present technology. depicts a sectional view of a seal-forming structure of a patient interface taken through line 7M-7M of according to an example of the present technology. depicts a posterior perspective view of a decoupling structure of a patient interface according to an example of the present technology. depicts an anterior perspective view of a decoupling structure of a t ace according to an example of the present technology. depicts a posterior perspective view of a decoupling ure of a patient interface according to an example of the present technology. depicts an anterior perspective view of a decoupling structure of a t interface according to an e of the present technology. depicts a superior perspective view of a patient interface according to an example of the present technology. depicts an anterior perspective view of a patient interface according to an example of the present technology.

A depicts an or perspective view of a patient interface according to an example of the present technology worn by a patient.

B depicts an anterior view of a patient interface ing to an example of the present technology worn by a patient.

C s a lateral view of a patient ace according to an e of the present technology worn by a patient.

D depicts a superior view of a patient interface according to an example of the t technology worn by a patient.

ResMed Ref: P1218NZ3 E depicts a superior view of a patient interface according to an example of the present technology worn by a patient.

Fig. 13A shows an anterior view of a patient interface ing to an example of the present technology on a patient.

Fig. 13B shows a superior and or view of a patient interface ing to an example of the t technology on a patient.

Fig. 13C shows a superior view of a patient interface according to an example of the present technology on a patient.

Fig. 13D shows a lateral view of a patient interface according to an example of the present technology on a patient.

Fig. 13E shows a partial lateral view of a patient interface according to an e of the present technology on a patient.

Fig. 13F shows another lateral view of a patient interface according to an example of the t technology on a patient.

Fig. 13G shows another partial lateral view of a patient interface according to an example of the present technology on a patient.

Fig. 13H shows a partial posterior view of a patient interface according to an example of the present technology.

Fig. 13I shows a l superior and posterior view of a patient interface according to an example of the present technology.

Fig. 14A shows an anterior view of a patient interface according to an example of the present technology on a patient.

Fig. 14B shows a l lateral view of a patient interface according to an example of the present technology on a patient.

ResMed Ref: P1218NZ3 Fig. 14C shows another partial anterolateral view of a patient interface according to an example of the present technology on a patient.

Fig. 14D shows a partial lateral view of a patient interface according to an example of the present technology on a patient.

Fig. 14E shows another partial lateral view of a patient interface according to an example of the t technology on a patient.

Fig. 14F shows another partial lateral view of a patient interface according to an example of the present logy on a patient.

Fig. 14G shows a partial lateral view of a patient interface according to an example of the present technology.

Fig. 14H shows a partial posterior view of a patient ace ing to an example of the present technology.

Fig. 14I shows a partial superior view of a patient interface according to an example of the t technology.

Fig. 14J shows a partial inferior view of a patient interface according to an example of the present technology.

Fig. 14K shows an anterior view of a patient interface according to an example of the present technology on a t where a rigidiser arm ly is deflected.

Fig. 15A shows a posterior perspective view of a seal forming structure of a t interface according to an example of the present technology.

Fig. 15B shows an anterior perspective view of a seal forming structure of a t interface ing to an example of the present technology.

Fig. 15C shows a ior view of a seal forming structure of a patient interface according to an example of the present technology.

ResMed Ref: P1218NZ3 Fig. 15D shows an anterior view of a seal forming structure of a patient interface ing to an example of the present technology.

Fig. 15E shows a superior view of a seal g structure of a patient interface according to an example of the present technology.

Fig. 15F shows an inferior view of a seal forming structure of a patient ace according to an example of the present technology.

Fig. 15G shows a lateral view of a seal forming structure of a patient interface according to an example of the present logy.

Fig. 15H shows a cross-sectional view of a seal forming structure of a patient interface according to an example of the present technology taken through line 15H-15H of Fig. 15D.

Fig. 15I shows a cross-sectional view of a seal forming structure of a t interface according to an example of the present technology taken through line 15I-15I of Fig. 15D.

J shows another anterior perspective view of a seal forming structure of a patient interface according to an e of the t technology.

Fig. 15K shows a cross-sectional view of a seal forming structure of a t interface according to an example of the present technology taken through line K of Fig. 15D.

DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY Before the present technology is described in further detail, it is to be understood that the technology is not limited to the particular examples bed herein, which may vary. It is also to be understood that the terminology used in this disclosure is for the purpose of describing only the particular examples discussed herein, and is not intended to be limiting.

ResMed Ref: P1218NZ3 The following description is provided in relation to various examples which may share one or more common characteristics and/or features. It is to be understood that one or more features of any one example may be combinable with one or more features of another example or other examples. In addition, any single feature or combination of features in any of the examples may constitute a further example. .1 THERAPY In one form, the present technology comprises a method for treating a respiratory disorder comprising the step of ng positive pressure to the entrance of the airways of a t 1000.

In certain examples of the present technology, a supply of air at positive pressure is ed to the nasal passages of the patient via one or both nares.

In certain examples of the present technology, mouth breathing is limited, restricted or prevented. .2 TREATMENT SYSTEMS In one form, the present technology ses an apparatus or device for treating a atory disorder. The apparatus or device may comprise an RPT device 4000 for ing pressurised air to the patient 1000 via an air circuit 4170 to a patient interface 3000. .3 T INTERFACE A non-invasive patient interface 3000 in accordance with one aspect of the t technology comprises the ing functional aspects: a seal-forming structure 3100, a plenum chamber 3200, a positioning and stabilising structure 3300, a vent 3400, one form of connection port 3600 for connection to air circuit 4170, and a forehead support 3700. In some forms a functional aspect may be ed by one or more physical components. In some forms, one physical component may provide one or more functional aspects. In use the seal-forming structure 3100 is arranged to surround an entrance to the airways of the patient so as to facilitate the supply of air at ve pressure to the airways.

ResMed Ref: P1218NZ3 If a t interface is unable to comfortably deliver a minimum level of positive pressure to the airways, the patient interface may be unsuitable for respiratory pressure therapy.

The patient interface 3000 in accordance with one form of the present technology is constructed and arranged to be able to provide a supply of air at a positive pressure of at least 6 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the present technology is constructed and arranged to be able to provide a supply of air at a positive re of at least 10 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the t technology is constructed and arranged to be able to provide a supply of air at a positive pressure of at least 20 cmH2O with respect to t. .3.1 Seal-forming structure In one form of the present technology, a seal-forming structure 3100 provides a target seal-forming region, and may additionally provide a cushioning function. The target seal-forming region is a region on the orming structure 3100 where sealing may occur. The region where g ly occurs- the actual sealing surface- may change within a given treatment session, from day to day, and from patient to patient, depending on a range of factors including for example, where the patient interface was placed on the face, n in the oning and stabilising structure and the shape of a patient’s face.

In one form the target seal-forming region is located on an outside surface of the seal-forming ure 3100.

In certain forms of the present technology, the seal-forming ure 3100 is constructed from a biocompatible material, e.g. silicone rubber.

A seal-forming structure 3100 in accordance with the present technology may be constructed from a soft, flexible, resilient material such as silicone.

ResMed Ref: P1218NZ3 In certain forms of the present technology, a system is ed comprising more than one a seal-forming structure 3100, each being configured to correspond to a different size and/or shape range. For example the system may comprise one form of a seal-forming structure 3100 suitable for a large sized head, but not a small sized head and r suitable for a small sized head, but not a large sized head. 1 Sealing mechanisms In one form, the seal-forming structure includes a sealing flange utilizing a pressure assisted sealing ism. In use, the sealing flange can readily respond to a system positive pressure in the interior of the plenum chamber 3200 acting on its underside to urge it into tight sealing engagement with the face. The pressure assisted mechanism may act in conjunction with elastic tension in the positioning and stabilising structure.

In one form, the seal-forming structure 3100 comprises a sealing flange and a support flange. The sealing flange comprises a relatively thin member with a thickness of less than about 1mm, for e about 0.25mm to about 0.45mm, which extends around the ter of the plenum chamber 3200. Support flange may be relatively thicker than the sealing flange. The support flange is disposed between the sealing flange and the marginal edge of the plenum chamber 3200, and extends at least part of the way around the ter. The t flange is or includes a springlike element and functions to t the sealing flange from buckling in use.

In one form, the seal-forming ure may comprise a compression sealing portion or a gasket sealing portion. In use the compression sealing portion, or the gasket sealing portion is constructed and arranged to be in compression, e.g. as a result of elastic tension in the positioning and stabilising structure.

In one form, the seal-forming structure comprises a tension portion. In use, the tension portion is held in tension, e.g. by adjacent regions of the sealing flange.

ResMed Ref: P1218NZ3 In one form, the seal-forming structure comprises a region having a tacky or adhesive surface.

In certain forms of the present technology, a seal-forming ure may comprise one or more of a pressure-assisted sealing , a compression sealing portion, a gasket sealing portion, a tension portion, and a portion having a tacky or adhesive surface. .3.1.2 Nose bridge or nose ridge region In one form, the non-invasive patient interface 3000 comprises a rming structure that forms a seal in use on a nose bridge region or on a nose-ridge region of the patient's face.

In one form, the orming structure includes a saddle-shaped region constructed to form a seal in use on a nose bridge region or on a nose-ridge region of the patient's face. .3.1.3 Upper lip region In one form, the non-invasive patient ace 3000 comprises a sealforming structure that forms a seal in use on an upper lip region (that is, the lip superior) of the patient's face.

In one form, the seal-forming structure includes a saddle-shaped region constructed to form a seal in use on an upper lip region of the patient's face. .3.1.4 Chin-region In one form the vasive patient interface 3000 comprises a sealforming structure that forms a seal in use on a chin-region of the patient's face.

In one form, the seal-forming structure es a saddle-shaped region constructed to form a seal in use on a chin-region of the patient's face.

ResMed Ref: P1218NZ3 .3.1.5 Forehead region In one form, the seal-forming structure that forms a seal in use on a forehead region of the patient's face. In such a form, the plenum chamber may cover the eyes in use. .3.1.6 Nasal pillows In one form the seal-forming ure of the non-invasive patient interface 3000 comprises a pair of nasal puffs, or nasal pillows, each nasal puff or nasal pillow being constructed and arranged to form a seal with a respective naris of the nose of a patient.

Nasal pillows in accordance with an aspect of the present technology include: a frusto-cone, at least a portion of which forms a seal on an underside of the patient's nose, a stalk, a flexible region on the underside of the frusto-cone and connecting the frusto-cone to the stalk. In addition, the structure to which the nasal pillow of the present technology is connected includes a flexible region adjacent the base of the stalk. The flexible regions can act in t to facilitate a universal joint structure that is accommodating of ve movement both displacement and angular of the frusto-cone and the structure to which the nasal pillow is connected. For example, the frusto-cone may be axially displaced towards the structure to which the stalk is connected. .3.1.7 Seal-Forming Structure With Support Structure FIGS. 7A to 7M depict a seal-forming structure 3100 according to an example of the present technology. Figs. 12A to 12E depict a patient ace 3000 with the seal-forming structure 3100 of this example of the t technology worn by a patient.The orming ure 3100 may be characterized as a nasal cradle cushion. The seal-forming structure 3100 may be structured to seal with the patient’s face around the t’s nares to provide the pressurized, breathable air to the patient’s nasal airways while not covering the patient’s mouth.

An inferior portion of the seal-forming structure 3100 may engage the patient’s lip or to form a seal, and the seal-forming structure 3100 may not ResMed Ref: P1218NZ3 extend beyond the lip superior, i.e., to the patient’s upper vermilion. In an example, a superior portion of the orming structure 3100 may be structured to engage the patient’s nose inferior to the patient’s nasal bone to form a seal. In another example, a or portion of the orming structure 3100 may be structured to engage the patient’s nose inferior to the patient’s pronasale to form a seal. Lateral portions of the seal-forming structure 3100 may be structured to engage the t’s nasal alar and the patient’s face between the patient’s nasal alar and the patient’s cheeks to form a seal, as can be seen in Figs. 12D and 12E. The lateral portions of the seal-forming ure 3100 may be structured to extend beyond the alar crest point to engage the patient’s face and form a seal.

The seal-forming structure 3100 according to the present technology may include utes of nasal cradle cushions disclosed in ational Application Publication Nos. filed November 14, 2014, each of which is incorporated herein by reference in its entirety.

The seal-forming structure 3100 according to the e depicted in FIGS. 7A to 7M es a connection region 3102 at an anterior side thereof. The connection region 3102 is structured to connect the seal-forming structure 3100 to the plenum chamber 3200. The connection region 3102 provides an interface for engagement with the plenum chamber 3200. The connection at the connection region 3102 may be substantially airtight to allow the desired pressure level to be ined in the plenum chamber 3200 during use. The connection region 3102 may connect with the plenum chamber 3200 via a mechanical connection such as a friction fit, a snap fit, or a mechanical interlock of corresponding overhanging portions. The connection region 3102 may provide a removable connection to the plenum chamber 3200. The removable connection allows the seal-forming structure 3100 to be removed for cleaning or ement. Alternatively, the connection between the sealforming structure 3100 and the plenum chamber 3200 may be permanent, e.g., via an adhesive or ulding, such that separating the seal-forming structure 3100 and the plenum chamber 3200 would damage one or both components. In this alternative, the seal-forming structure 3100 and the plenum chamber 3200 may be replaceable as ResMed Ref: P1218NZ3 a combined unit. In another example, the seal-forming structure 3100 and the plenum chamber 3200 may be formed from one homogeneous piece of material, which may be elastomeric or which may be silicone.

The connection region 3102 of this example surrounds an anterior opening 3104 or hole. The anterior opening 3104 may be in fluid communication with the plenum chamber 3200 to receive the flow of pressurized, breathable gas, and exhaled gas from the patient may pass through the anterior opening 3104 to the plenum chamber 3200 to be exhausted by the vent 3400. The anterior opening 3104 in this example is also divided by an anterior tie 3108 that spans the anterior opening 3104 in a superior-inferior direction between an inferior portion of the connection region 3102 and a superior portion of the connection region 3102. The anterior tie 3108 may span the minor axis of the anterior opening 3104.

The seal-forming structure 3100 of this example also includes a nonpatient ting surface 3116 surrounding the connection region 3102. The non- patient contacting surface 3116 faces away from the t’s face and does not contact the patient’s face in use. The non-patient contacting surface 3116 may also at least partly contact the plenum chamber 3200.

The orming ure 3100 of this example also includes a tcontacting surface 3114. The patient-contacting surface 3114 faces the patient’s face in use. The patient-contacting surface 3114 may at least partially seal against the t’s facial skin in use. The patient-contacting surface 3114 is arranged such that the patient’s facial skin contacts the patient-contacting surface 3114 in use. The patient’s facial skin may contact only parts of the patient-contacting e 3114 or the patient’s facial skin may contact all of the t-contacting surface 3114 in use.

The patient-contacting surface 3114 may be adjacent to the non-patient ting surface 3116. The patient-contacting e 3114 may also be contiguous with the non-patient contacting surface 3116. The patient-contacting surface 3114 and the ient contacting surface 3116 may be at least one of frosted, opaque, smooth, and glossy. The patient-contacting surface 3114 and the non-patient ting surface 3116 may have different e textures, e.g., frosted, opaque, smooth, and/or glossy.

ResMed Ref: P1218NZ3 The seal-forming structure 3100 of this example also includes a chamber 3120 bounded at least partially by an interior surface 3112 of the seal-forming structure 3100. The chamber 3120 may be rized up to 30 cmH2O by the pressurized, able gas received from the plenum chamber 3200 during use.

As can be seen in the posterior view of Fig. 7D, a posterior opening 3106 or hole is formed in the t-contacting surface 3114. Pressurized, breathable gas in the chamber 3120 of the seal-forming structure 3100 is communicated to the patient’s nares through the posterior opening 3106. Gas exhaled from the patient’s nares is communicated through the posterior opening 3106 to the chamber 3120 to be exhausted via the vent 3400. The posterior opening 3106 may be a single g formed in the patient-contacting surface 3114 or the posterior opening 3106 may be divided into two separate openings that each communicates with a corresponding naris of the patient. The ior opening 3106 may be bounded by an edge 3118 of the patient-contacting surface 3114.

The seal-forming structure 3100 of this example also includes a support structure 3110 that can be seen in FIGS. 7C, 7J, and 7M. The support structure 3110 is connected to the anterior tie 3108 at one end, and the connection is with the surface of the anterior tie 3108 that faces the interior of the chamber 3120 or the connection faces in a posterior direction relative to the seal-forming structure 3100. The other end of the support structure 3110 is connected to the t-contacting surface 3114 at the edge 3118.

As can be seen in the cross-sectional views of FIGS. 7G to 7K and 7M, a or portion of the patient-contacting surface 3114 of the seal-forming structure 3100 is not ted by an undercushion. The patient-contacting e 3114 of the seal-forming structure 3100 may be a single layer that engages the patient’s nose proximate to the pronasale. The single layer of the seal-forming structure 3100 in this region may be more flexible as compared to a dual-wall arrangement, i.e., an arrangement with an undercushion, which may provide a more comfortable and effective seal for a wider range of nose . However, such a single layer arrangement may be more prone to t, e.g., where the pressurized, breathable ResMed Ref: P1218NZ3 gas causes the patient-contacting e 3114 of the seal-forming structure 3100 to disengage from the t’s nose. The support structure 3110 counteracts this effect by tying the edge 3118 of the patient-contacting e 3114 to another portion of the seal-forming structure 3100. The support structure 3110 may provide support to the superior portion of the patient-contacting surface 3114 of the seal-forming structure 3100 to prevent blowout by restraining deflection of the edge 3118 and the surrounding patient-contacting surface 3114.

Blowout may be understood to refer to the deformation of the seal forming structure 3100 that is caused, at least in part, by the pressure differential resulting from the ation of pressure during therapy such that the patientcontacting surface 3114 is displaced from sealing contact with the patient’s face, e.g., around the underside of the patient’s nose. For example, the patient may pull the patient interface 3000 away from the face during therapy (i.e., while pressure is being applied) and when the patient interface 3000 is displaced from the patient’s face by the t, the force of the therapy pressure may cause the seal forming structure 3100 to deform. When the patient interface 3000 is then reapplied to the patient’s face by the patient, the t-contacting surface 3114 of the seal forming ure 3100 may be displaced due to deformation such that an ineffective seal is formed and pressurized gas leaks from the seal forming structure 3100. During this repositioning of the seal g structure 3100, it is le for the internal pressurisation of the plenum chamber 3200 to be disturbed and cause a pressure gradient proximal to the edge 3118. The pressure gradient may provide a force, which may ultimately lead to blow out of the patient-contacting e 3114. cement of the patient-contacting surface 3114 during blow out may move the edge 3118 into a position that interrupts the seal by forming leak paths when the seal-forming structure 3100 is again repositioned onto the face. When blowout of the seal forming structure 3100 occurs at regions proximal to the patient’s eyes (e.g., when the patient-contacting surface 3114 proximal to the nasal alar is displaced), the pressurized gas may flow towards the patient’s eyes, which may be particularly disruptive and some to the patient. Accordingly, it is advantageous to reduce ResMed Ref: P1218NZ3 blowout so that adequate sealing is maintained to ensure that the patient receives gas at the intended pressure and so that the t is not disturbed.

The deformation that blowout may subject the seal forming structure 3100 to may be in an outward direction, e.g., away from the patient’s face. Indeed, in extreme conditions under high al pressurisation, blow out may include the seal forming structure 3100 folding backwards upon itself. For example, without the support structure 3110, the patient-contacting surface 3114 might t such that the edge 3118 contacts the patient-contacting surface 3114.

The nose shape can be highly variable in profile between users. Moreover, to seal in this region the inner edge of the patient-contacting e 3114 may bend inwards (e.g., into the plenum chamber and orthogonal to the Frankfort horizontal) and deform to follow the profile of the sides of the nose. As such, this area may be particularly prone to seal interruptions following blow out. That is, if the patientcontacting surface 3114 is outwardly displaced (e.g., away from the t’s face) during blow out, it is often difficult to return the edge 3118 to a sealing position due to resistance from the force of the pressurized gas.

Blowout may also occur in other areas such as the cheek region or at the upper or lower lip regions which are less prone to seal uption, but these regions have a generally flatter profile substantially along the coronal plane. During blow out, the edge 3118 may not move significantly from a position that is required to seal along this plane and often the sealing force provided by the positioning and stabilising structure 3300 is sufficient to reposition the edge 3118 to an orientation required to regain seal.

While dual wall seal forming structures 3100 may be susceptible to blowout, single wall seal forming ures 3100 such as those disclosed in examples of the present logy, may be particularly tible to blowout. The absence of an additional undercushion structure supporting the t-contacting surface 3114 may be understood to allow the t-contacting surface 3114 to deform and deflect more easily. Moreover, the undercushion in a dual wall cushion may help to ResMed Ref: P1218NZ3 reposition the outer, sealing wall against the patient’s face when the patient interface 3000 is repositioned, but this assistance may be absent in a single wall cushion.

The support structure 3110 may also partially contact the patient’s columella to prevent the patient’s nose from protruding into the chamber 3120 of the seal-forming structure 3100. The support structure 3110 may also support the tcontacting surface 3114 and urge the patient-contacting surface 3114 into engagement with the patient’s nose proximate to the pronasale to ensure effective g. , for example, also shows that the support structure 3110 does not span the posterior opening 3106 and does not extend between a superior portion and an inferior portion of the edge 3118.

The support structure 3110 may, along with the or surface 3112 and the anterior tie 3108 of the seal-forming structure 3100, form a continuous loop, as can be seen in . In an alternative example, the support structure 3110 may be connected to the interior surface 3112 of the seal-forming structure 3100 and not to the anterior tie 3108. In such an alternative e, the or tie 3108 may be omitted. also shows that the support structure 3110 is curved slightly inward into the chamber 3120 in an undeformed state. This curvature may allow the support structure 3110 to better accommodate the patient’s nose, ing the pronasale. Alternatively, the support structure 3110 may be straight in an undeformed state of another example. Additionally, shows that the patient-contacting surface 3114 is contiguous with an external or posterior surface of the support structure 3110. In an alternative e, the support structure 3110 may be connected to the or e 3112 of the seal-forming structure 3100 te the patient-contacting surface 3114 such that the edge 3118 separates the patientcontacting surface 3114 and the support ure 3110.

The orming structure 3100, particularly the support structure 3110, may include attributes of the tie 3110 disclosed by International Application Publication No. by reference in its entirety.

ResMed Ref: P1218NZ3 The seal-forming structure 3100 may also include an undercushion 3122 that supports a portion of the patient-contacting surface 3114, as can be seen in FIGS. 7G to 7M. The undercushion 3122 may only support an inferior portion of the undercushion 3122. The undercushion 3122 may be provided to only the lower half of the seal-forming structure 3100. The undercushion 3122 of these examples may be configured to support the patient-contacting surface 3114 against the patient’s lip superior to ensure an effective seal. A similar undercushion layer 3135 is disclosed by the es depicted in Figs. 15A to 15K. .3.1.8 Seal-Forming Structure With Columella Engagement Portion According to an example of the present technology, the seal-forming ure 3130 may include an outer membrane 3139 to seal against the patient’s face and around the entrance(s) to the patient’s s, such as the nares, as shown in Figs. 15A to 15C, 15E, and 15F. The outer membrane 3139 may form a seal around the inferior periphery of the patient’s nose. In the ary orming structures 3130 depicted in FIGS. 13A-13I, 14A-14J, and 15A-15K, the seal-forming structures 3130 each have a pair of openings 3132, each of which provides the flow of pressurized gas to a ponding naris of the patient’s nose. These examples also include a columella engagement portion 3133 between the openings 3132 that engages the patient’s columella. The columella engagement n 3133 may prevent the patient’s nose from ing through the openings 3132 and into the interior region of the seal-forming structure 3130. In an alternative example, there may be a single opening 3132 that provides the flow of pressurized to both of the patient’s nares.

The outer membrane 3139 may also e several regions that seal against different respective s of the patient’s face. Such examples are depicted in FIGS. 15A-15K. The outer membrane 3139 of the exemplary seal-forming structure 3130 may include a superior portion 3140 that forms a seal at the pronasale , i.e., the tip, of the patient’s nose, as shown in Figs. 13A to 13C, 14A, 14B, and 14E. The outer membrane 3139 may be shaped and dimensioned such that in use the superior portion 3140 does not extend beyond the patient’s septal cartilage or the ResMed Ref: P1218NZ3 patient’s alar cartilage, which are depicted in FIGS. 2H, 2I, and 2L. atively, the superior portion 3140 may not engage the patient’s nose in use beyond the pronasale.

The seal-forming structure 3130 may also include an inferior portion 3141 that forms a seal with the patient’s lip superior, i.e., the upper lip. The inferior portion 3141 may be curved to correspond to the curvature of the patient’s lip superior.

The seal-forming structure 3130 may also include lateral ns 3142 to seal around and under the alae of the patient’s nose. The seal-forming structure 3130 may also include alar sealing portions 3131 between the inferior portion 3141 and each lateral portion 3142 that form a seal against the patient’s face between the ala and corresponding nasolabial sulcus on each side of the patient’s nose, as shown in Figs. 13A to 13C.

The outer membrane 3139 of the seal-forming structure 3130 may also include thickened regions 3134 at each lateral portion 3142. FIGS. 14H and 14I depict the outline of the ned regions 3134, but it should be understood that the additional thickness of the outer membrane 3139 at the thickened regions 3134 may extend inwardly from an interior surface of outer membrane 3139 such that the patient-contacting e of the outer ne 3139 is smooth. FIGS. 15D and 15I depict such examples. The thickened regions 3134 may prevent buckling of the outer membrane 3139 of the seal-forming structure 3130 in use by providing additional structural strength, while ng the remaining regions of the outer membrane 3139 to be relatively thin and, thus, more conformable to the contours of the patient’s face. .3.1.8.1 ushion Layer The seal-forming structure 3130 may also include an undercushion layer 3135 to support the outer membrane 3139 against the patient’s face in use to ensure te pneumatic g. As can be seen in FIGS. 15B, 15H, 15J, and 15K, the undercushion layer 3135 may extend only around the inferior half of the outer membrane 3139. Accordingly, the undercushion layer 3135 may provide support for only the inferior portion 3141 of the outer membrane 3139 against the t’s lip superior. The undercushion layer 3135 may also include alar sealing n supports 3137 that extend into and support the respective alar g portions 3131 of the ResMed Ref: P1218NZ3 outer membrane 3139. The alar sealing portion supports 3137 may prevent creases in the outer membrane 3139. The alar sealing portion supports 3137 may also help t the alar sealing ns 3131 when engaged with the patient’s face between the alae and the nasolabial sulci – the complex geometry of this region of the face may require additional t to ensure that an adequate seal is ined. The outer membrane 3139 of the seal forming structure 3130 and the ushion layer 3135 may be formed from one neous piece of material, which may be silicone according to example of the present technology.

The undercushion layer 3135 may prevent buckling of the outer membrane 3139, which may be thinner and therefore more susceptible to buckling when urged against the patient’s face.

The undercushion layer 3135 may provide t for the orming structure 3130 by resisting the tension forces generated by the oning and stabilising ure 3330. The undercushion layer 3135 may e vertical support of the seal-forming structure 3130 by preventing the orming structure 3130 from moving in a superior direction relative to the patient’s nose due to forces from the positioning and stabilizing structure 3130 that are directed at least partially in a superior direction relative to the patient’s nose. The undercushion layer 3135 may provide support for the seal-forming structure 3130 in lateral directions by resisting forces of the positioning and stabilising structure 3330 that push the seal-forming structure 3130 onto the patient’s face in use. Such enhancements to lateral stability of the seal-forming structure 3130 may be particularly enhanced when the flow of air from the RPT device 4000 is turned off during fitting of the patient interface 3000.

The undercushion layer 3135 may provide stability by resisting movement of the seal-forming structure 3130 when engaged with the patient’s face in use and/or may aid in locating the seal-forming structure 3130 by aligning it with the patient’s nose in use. The undercushion layer 3135 may aid in locating the seal-forming structure 3130 in lateral directions by encouraging the seal-forming structure 3130 to engage the patient’s face at an optimally centered position relative to the patient’s nose and may also resist l movement of the seal-forming structure 3130 when ResMed Ref: P1218NZ3 subjected to external forces by the patient or ndings (e.g., a pillow or tube drag). The undercushion layer 3135 may also aid in locating the seal-forming structure 3130 in a superior direction relative to the patient’s nose by encouraging the seal-forming structure 3130 to engage the patient’s face at an optimally centered position relative to the patient’s nose and may also resist movement in a superior direction when subjected to external forces by the patient or surroundings (e.g., a pillow or tube drag). .3.1.8.2 Outer Membrane The outer membrane 3139 of the seal-forming ure 3130 may be shaped and dimensioned at the corner regions of the outer membrane, i.e., the regions between the superior portion 3140 and the lateral portions 3142 to accommodate patients with certain pometry that have a large portion of their nasal vestibule (nostril opening) exposed at the side/laterally. Typically such patients have a high alar rim or a hanging columella and as such it may be beneficial to extend the or portion 3140 and the l portions 3142 to accommodate such patients. Structuring the superior portion 3140 and the lateral ns 3142 in this way may also prevent crushing of the outer membrane 3139 or unintended deformation of the outer membrane 3139 when pressurized gas is not being supplied (e.g., when the user has just donned the mask) to improve usability when g, or when there is low pressure therapy (less than 4cm H2O).

The orm structure 3130 may also include a recess or recessed portion 3136 at its anterior side. The recess 3136 provides space for the rigidiser arm connectors 3337 that are described in detail below to move when forces are imparted on the rigidiser arms 3331 by the patient in use. As described below, the exemplary positioning and stabilising structure 3330 may include a rigidiser arm assembly that may move laterally. Accordingly, the recess 3136 may provide a clearance in the rming structure 3130 for the rigidiser arm connectors 3337. Also, the recess 3136 may maximise the cushioning properties of the ushion layer 3135 around the patient’s top lip.

ResMed Ref: Z3 The orming structure 3130 may also e a plenum chamber connection portion 3138 at which the orming structure 3130 attaches to the plenum chamber 3200. This connection may be permanent, e.g., due to a mechanical interlock or chemical bond, or the tion may be releasable to allow the patient to separate the seal-forming structure 3130 from the plenum chamber 3200. The connection at the plenum chamber connection portion 3138 may be substantially airtight to allow the d pressure level to be maintained in the plenum chamber 3200 during use. Also, the plenum chamber tion portion 3138 may surround the entire anterior ery of the seal-forming structure 3130 for attachment to the plenum chamber 3200.

K also shows how the undercushion layer 3135 may be profiled to conform to the patient’s upper lip, while minimizing leak through the seal formed by the outer membrane 3139. The undercushion layer 3135 includes outwardly curved portions 3145 that are curved to generally follow the contours of the patient’s upper lip, since the undercushion layer 3135 will support the outer membrane 3139 against the patient’s upper lip. Inwardly curved portions 3144 are also shown between the outwardly curved portions 3145 on the undercushion layer 3135. These inwardly curved portions 3144 help the undercushion layer 3135 support the outer ne 3139 against the patient’s upper lip to prevent leak by being curved inwardly such that a given displacement of the undercushion layer 3135 at the inwardly curved portions 3144 does not displace the undercushion layer 3135 so far that air leaks past the outer membrane 3139. The inwardly curved portions 3144 are located to prevent leak in rone areas, which are typically along the lip superior and below the nostrils and .3.2 Plenum chamber The plenum chamber 3200 has a perimeter that is shaped to be complementary to the surface contour of the face of an average person in the region where a seal will form in use. In use, a marginal edge of the plenum chamber 3200 is positioned in close proximity to an adjacent surface of the face. Actual contact with the face is provided by the seal-forming structure 3100. The seal-forming structure 3100 may extend in use about the entire perimeter of the plenum chamber 3200. In ResMed Ref: P1218NZ3 some forms, the plenum chamber 3200 and the orming structure 3100 are formed from a single homogeneous piece of al.

In certain forms of the present technology, the plenum r 3200 does not cover the eyes of the patient in use. In other words, the eyes are outside the pressurised volume defined by the plenum chamber. Such forms tend to be less obtrusive and / or more comfortable for the wearer, which can improve compliance with therapy.

In certain forms of the present technology, the plenum chamber 3200 is constructed from a transparent material, e.g. a transparent polycarbonate. The use of a transparent material can reduce the obtrusiveness of the t interface, and help improve compliance with therapy. The use of a transparent material can aid a ian to observe how the patient interface is located and oning.

In certain forms of the present technology, the plenum chamber 3200 is constructed from a translucent material. The use of a translucent material can reduce the obtrusiveness of the patient interface, and help improve compliance with therapy. .3.3 Positioning and stabilising structure The seal-forming structure 3100 of the patient interface 3000 of the present technology may be held in sealing position in use by the positioning and ising structure 3300.

In one form the positioning and stabilising structure 3300 provides a retention force at least sufficient to overcome the effect of the positive pressure in the plenum chamber 3200 to lift off the face.

In one form the positioning and stabilising structure 3300 provides a retention force to overcome the effect of the ational force on the t interface 3000.

In one form the positioning and stabilising structure 3300 provides a retention force as a safety margin to overcome the potential effect of disrupting forces ResMed Ref: P1218NZ3 on the patient interface 3000, such as from tube drag, or accidental erence with the patient interface.

In one form of the present technology, a positioning and stabilising structure 3300 is ed that is configured in a manner consistent with being worn by a patient while sleeping. In one e the positioning and ising structure 3300 has a low e, or cross-sectional thickness, to reduce the perceived or actual bulk of the apparatus. In one example, the positioning and stabilising structure 3300 comprises at least one strap having a rectangular cross-section. In one example the positioning and stabilising structure 3300 comprises at least one flat strap.

In one form of the present technology, a positioning and stabilising structure 3300 is provided that is configured so as not to be too large and bulky to prevent the patient from lying in a supine sleeping position with a back region of the patient’s head on a pillow.

In one form of the present technology, a positioning and stabilising structure 3300 is provided that is configured so as not to be too large and bulky to prevent the patient from lying in a side sleeping position with a side region of the patient’s head on a pillow.

In one form of the present technology, a oning and stabilising structure 3300 is provided with a decoupling portion located between an anterior portion of the positioning and stabilising structure 3300, and a posterior portion of the positioning and stabilising structure 3300. The decoupling portion does not resist compression and may be, e.g. a le or floppy strap. The decoupling portion is ucted and arranged so that when the patient lies with their head on a pillow, the presence of the decoupling n prevents a force on the posterior portion from being transmitted along the oning and stabilising structure 3300 and disrupting the seal.

In one form of the present technology, a oning and stabilising structure 3300 comprises a strap constructed from a laminate of a fabric patientcontacting layer, a foam inner layer and a fabric outer layer. In one form, the foam is ResMed Ref: P1218NZ3 porous to allow moisture, (e.g., sweat), to pass through the strap. In one form, the fabric outer layer comprises loop material to engage with a hook material portion.

In certain forms of the present technology, a oning and stabilising structure 3300 comprises a strap that is ible, e.g. resiliently extensible. For e the strap may be configured in use to be in tension, and to direct a force to draw a seal-forming structure into sealing contact with a portion of a patient’s face. In an e the strap may be configured as a tie.

In one form of the present technology, the positioning and stabilising structure comprises a first tie, the first tie being constructed and arranged so that in use at least a portion of an or edge thereof passes superior to an otobasion superior of the patient’s head and overlays a portion of the parietal bone without overlaying the tal bone.

In one form of the present technology suitable for a nasal-only mask or for a full-face mask, the positioning and stabilising structure includes a second tie, the second tie being constructed and ed so that in use at least a portion of a superior edge thereof passes inferior to an otobasion or of the patient’s head and overlays or lies inferior to the occipital bone of the patient’s head.

In one form of the present technology suitable for a nasal-only mask or for a full-face mask, the positioning and stabilising structure includes a third tie that is ucted and ed to interconnect the first tie and the second tie to reduce a tendency of the first tie and the second tie to move apart from one another.

In certain forms of the present technology, a positioning and stabilising structure 3300 comprises a strap that is bendable and e.g. non-rigid. An advantage of this aspect is that the strap is more comfortable for a t to lie upon while the patient is sleeping.

In certain forms of the present technology, a positioning and stabilising structure 3300 comprises a strap constructed to be breathable to allow moisture vapour to be transmitted through the strap, ResMed Ref: P1218NZ3 In certain forms of the present technology, a system is provided comprising more than one positioning and izing structure 3300, each being configured to provide a retaining force to correspond to a different size and/or shape range. For example the system may se one form of positioning and izing structure 3300 le for a large sized head, but not a small sized head, and another. suitable for a small sized head, but not a large sized head.

The positioning and stabilizing structure 3330 according to examples of the present technology, shown in Figs. 13A to 13I and 14A to 14J, may decouple forces generated when the patient lies on their cheek or the side of their head to prevent dislodging of the seal-forming structure 3130 from sealing against the areas surrounding the entrance(s) of the patient’s s. The seal-forming structure 3130 of the present technology, examples of which are bed above, may have less sealing surface area than other types of seal-forming structures and may also not have the ability of nasal pillows to physically "key" into a patient’s nares to maintain the sealing position. Thus, the seal-forming structure 3130 of the present technology may be more susceptible to seal disruption from forces experienced during therapy (e.g., tube torque, the patient sleeping on their cheek or side of their head, etc.) than other types of seal-forming structures.

The positioning and stabilizing structure 3330 of the present technology may decouple forces generated when the t lies on their cheek or the side of their head to prevent lateral nt of the seal-forming structure 3130. The decoupled positioning and stabilising structure 3330 may s the issue of side stability of the seal-forming structure 3130 by being decoupled from both the plenum chamber 3200 and the seal-forming structure 3130. It has been observed that the patient’s skin moves relatively to the seal-forming structure 3130 in use. In other words, the skin is static but the skull moves. Accordingly, if the skull moves, the nose moves too, which may be tood to be the root cause of destabilisation of the seal-forming structure 3130.

The positioning and stabilising structure 3330 may include rigidiser arms 3331 that may be made from a thermoplastic elastomer, such as Hytrel®. The plenum ResMed Ref: P1218NZ3 chamber 3200 and the seal-forming structure 3130 may pivot in the middle or medial region relative to the positioning and ising structure 3330 to decouple forces caused by the patient rolling onto the side of their cheek or the side of their head. The superior portion 3140 and the lateral portions 3142 of the seal-forming ure 3130 may stay with the nose during such motion, but the forces ed onto the positioning and stabilising structure 3330 by the patient’s movement may be isolated or decoupled. For example, the positioning and stabilising structure 3330 may be connected to the plenum r 3200 such that forces imposed on the positioning and stabilising structure 3330 by nt of the patient’s head are decoupled from the plenum chamber 3200 and the seal forming structure 3130.

In the examples depicted in FIGS. 14A to 14K, the positioning and stabilising structure 3330 may include a rigidiser arm assembly 3342 that is flexibly attached to the plenum chamber. Also, the rigidiser arm assembly 3342 may be flexibly attached to the plenum chamber such that in use the rigidiser arm assembly 3342 is e substantially independently relative to the plenum chamber 3200 and the seal forming structure 3130. This may be accomplished by flexibly attaching the rigidiser arm assembly 3342 to the plenum chamber 3200 such that movement of the positioning and stabilising structure 3330 in use does not disrupt the sealing contact of the seal forming structure 3130 with the area surrounding the ce to the t’s airways. As described above, the rigidiser arm assembly 3342 may be flexibly attached to a medial, anterior surface of the plenum chamber 3200. The rigidiser arm assembly 3342 may also be ly attached to the plenum chamber 3200 with an c material.

The rigidiser arm assembly 3342 may be flexibly connected to the plenum chamber 3200 by at least one flexible ling structure 3340 such that forces imposed on the positioning and stabilising structure 3330, e.g., the rigidiser arms 3331, by movement of the patient’s head are decoupled from the plenum chamber 3200 and the seal forming structure 3130. The plenum chamber 3200 may include a plenum chamber connector 3341 and the ser arm assembly 3342 may include a rigidiser arm connection ring 3338 that are flexibly connected by the at least one flexible decoupling structure 3340. The at least one flexible decoupling structure 3340 ResMed Ref: Z3 may be made from an c material. The plenum chamber connector 3341 may be fixed to a medial, anterior surface of the plenum chamber 3200. The rigidiser arm assembly 3342 may e two rigidiser arm connectors 3337 connecting a corresponding rigidiser arm 3331 to the rigidiser arm connection ring 3338. The ser arm connection ring 3338 and the two rigidiser arm connectors 3337 may be formed from one homogeneous piece of a first material, such as silicone. The rigidiser arm connection ring 3338 may be joined to a ler connection ring 3339 that is joined to the at least one flexible decoupling structure 3340, which is in turn ed to the plenum chamber connector 3341. Also, each of the rigidiser arms 3331 may be formed from a second material, such as a thermoplastic elastomer, that is different from the first material. The first material may be more rigid than the second material.

Each of the rigidiser arms 3331 may be connected to a ponding one of the rigidiser arm connectors 3337 with a chemical bond or a mechanical interlock. In an alternative example, the ser arms 3331, the rigidiser arm connectors 3337, and the rigidiser arm connection ring 3338 may be formed from one homogeneous piece of material, such as silicone or plastic elastomer.

The rigidiser arm connection ring 3338, the decoupler connection ring 3339, and the plenum chamber connector 3341 are all shaped with a passage or in an open construction to allow the air circuit 4170 to pass through to the connection port 3600 (not visible) and connect to the plenum chamber 3200 to provide the pressurized gas to the t.

In use, this exemplary patient interface 3000 may allow forces imparted on the rigidiser arms 3331 of the positioning and stabilising structure 3330 by the patient laying on the side of their head or cheek to be isolated or decoupled from the plenum chamber 3200 and the seal-forming structure 3130, because the only connection from the rigidiser arm assembly 3342 to the plenum chamber 3200 and the seal-forming structure 3130 is through the flexible decoupling structures 3340.

Accordingly, when the orming ure 3130 is engaged with the patient’s face during therapy, such forces imparted on the rigidiser arms 3331 that may cause movement in the rigidiser arm assembly 3342 are isolated or decoupled by elastic ResMed Ref: Z3 deformation of the le decoupling structures 3340 in the form of compression or extension, as can be seen in Fig. 14K.

In the depicted example, there are two flexible decoupling structures 3340 at a superior side, as shown in I, providing the connection, as well as two flexible decoupling structures 3340 provided on the opposite, inferior side that are not visible in J due to the rigidiser arm connectors 3337. In other words, there are two flexible decoupling ures 3340 at the twelve o’clock on and two flexible decoupling ures 3340 at the six o’clock position as viewed from an anterior perspective. Accordingly, when the rigidiser arm assembly 3342 is moved to the right side of the t’s head, the right flexible decoupling structures 3340 are compressed and the left flexible decoupling structures 3340 are ed and when the rigidiser arm assembly 3342 is moved to the left side of the patient’s head, the left flexible decoupling structures 3340 are compressed and the right flexible decoupling structures 3340 are extended, as shown in Fig. 14K. The flexible decoupling ures 3340 may also provide for flexibility of the connection when the rigidiser arm assembly 3342 is moved in the superior and inferior directions relative to the plenum chamber 3200 and the seal-forming structure 3130. This may be accomplished by joining the decoupler connection ring 3339 and the plenum chamber connector 3341 at the l sides, i.e., at the three o’clock and the nine o’clock ons as viewed from an anterior perspective.

It should be understood that only one flexible decoupling structure 3340 is necessary. Also, more than two flexible decoupling structures 3340 may be provided depending on the degree of flexibility desired at the connection.

The positioning and stabilising structure 3330 may also include a plurality of straps, which may include side straps 3332, a crown strap 3333 to engage the patient’s head proximal to the parietal bone, and a rear strap 3335 to engage the patient’s head proximal to the occipital bone, to secure the patient interface on the patient’s head in use by attachment to the rigidiser arm assembly 3342. The plurality of straps may only be ted to the rigidiser arm assembly 3342 to retain the seal- ResMed Ref: P1218NZ3 forming structure 3130 in sealing engagement with the area surrounding the entrances to the patient’s airways.

The rigidiser arm assembly 3342 may include two rigider arms 3331 that are configured to pass along the patient’s cheeks in use. Each of the rigidiser arms 3331 may also have an opening 3334 such that each of the side straps 3332 connect to the corresponding rigidiser arm 3331 at the opening 3334. Each of the side straps 3332 may e one of a hook material and a loop material and each of the side straps 3332 may include a connector 3336 of the other of the hook material and the loop material to secure the side straps 3332 to the rigidiser arms 3331 through each opening 3334. Furthermore, the positioning and stabilising structure 3330 may be shaped and dimensioned such that each of the side straps 3332 pass below the patient’s eye and above the patient’s ear in use.

The plurality of straps of the positioning and stabilising structure 3330 may be made from different materials and/or may a have different elasticity. These different materials may e textile, foam, and breathable neoprene. It has also been observed that the force vector of the side straps 3332 is predominantly nced by the rear strap 3335 and less so by the crown strap 3333. Accordingly, in one example the rear strap 3335 may be more c than the crown strap 3333. The crown strap 3333 being relatively inelastic may be length-adjustable to allow it to accommodate different shapes and sizes of a t’s head and the rear strap 3335 may not be length able, because it is elastic.

The rigidiser arms 3331 may also be shaped to conform to the shape of the patient’s cheeks so as not to protrude out from the face in use. This arrangement may provide a more streamlined appearance that is more visually appealing. This arrangement may also allow forces to only act against the rigidiser arm 3331 when pressure is applied by the patient’s cheek pushing against the bed pillow. .3.4 Vent In one form, the patient interface 3000 includes a vent 3400 constructed and ed to allow for the washout of exhaled gases, e.g. carbon dioxide.

ResMed Ref: P1218NZ3 In certain forms the vent 3400 is configured to allow a continuous vent flow from an interior of the plenum chamber 3200 to ambient whilst the pressure within the plenum chamber is ve with respect to ambient. The vent 3400 is configured such that the vent flow rate has a magnitude sufficient to reduce rebreathing of exhaled CO2 by the patient while maintaining the therapeutic pressure in the plenum r in use.

One form of vent 3400 in accordance with the present technology comprises a plurality of holes, for example, about 20 to about 80 holes, or about 40 to about 60 holes, or about 45 to about 55 holes.

The vent 3400 may be located in the plenum chamber 3200. Alternatively, the vent 3400 is located in a decoupling structure, e.g., a .

In Fig. 11, an exemplary vent 3400, e.g., for CO2 washout, is depicted on the plenum r 3200. A vent 3400 may be provided on the seal-forming structure 3100 in another example. The elbow connector 3305 may include a vent 3400 in another example. A vent 3400 (e.g., for discharging CO2 from the patient to atmosphere and/or as a bleed off for pressurized gas provided by the source of pressure (e.g., blower/PAP device)) may also be provided to one or both of the le portions 3304 in another e. Gas discharged through these holes may provide ventilation for the patient. A vent 3400 may also be provided to one or both of the conduits 3301 in another example, and gas discharged h these holes may provide ventilation for the patient. .3.5 Decoupling structure(s) In one form the patient interface 3000 includes at least one decoupling structure 3500, for example, a swivel or a ball and socket. FIGS. 8A, 8B, 9A, and 9B depict examples of decoupling structures 3500 according to examples of the t technology. The decoupling structures 3500 may be in the form of an elbow. The decoupling structures 3500 may e a swivel that connects to the air circuit 4170 and a patient interface connector 3502 that connects to the t interface 3000. The patient interface connector 3502 may permit the decoupling structure 3500 to rotate relative to the patient interface 3000. The decoupling structures 3500 may also ResMed Ref: P1218NZ3 include vent holes 3401. For example, FIGS. 8A, 8B, 9A, and 9B show two variations in number and arrangement of the vent holes 3401 on the decoupling structure 3500.

These vent holes 3401 may allow for pressurized gas delivered to the patient interface 3000 to be bled off. It is also possible for d CO2 from the patient to escape to atmosphere via the vent holes 3401 in the decoupling structure 3500. In r example, the vent holes can be provided in an added ent, e.g., an adapter in the form of a vely short flexible or rigid conduit (2-10 cm) with holes attached to the patient interface 3000, e.g., connected to the decoupling structure 3500. The short conduit can be sold with a patient interface and include an appropriate number of holes to allow bleed off of the pressurized gas to tune the therapeutic pressure to an appropriate level for the given patient interface 3000. The CO2 vent and the bleed off vent may have the same or different capacities, e.g., the bleed off vent may provide a higher or lower flow rate than the CO2 vent. .3.6 Connection port Connection port 3600 allows for connection to the air circuit 4170. .3.7 Forehead support In one form, the patient interface 3000 includes a forehead support 3700. .3.8 Anti-asphyxia valve In one form, the patient interface 3000 includes an anti-asphyxia valve. .3.9 Ports In one form of the present technology, a patient interface 3000 includes one or more ports that allow access to the volume within the plenum r 3200.

In one form this allows a clinician to supply supplemental oxygen. In one form, this allows for the direct measurement of a property of gases within the plenum chamber 3200, such as the re. .3.10 Patient Interface FIGS. 10 and 11 depict a patient interface 3000 according to an example of the present logy. The patient interface 3000 includes the seal-forming ResMed Ref: P1218NZ3 structure 3100 according to the examples described in section 5.3.1.7above. The sealforming structure 3100 may be ted to the plenum chamber 3200 as described above as well. The plenum r 3200 may be provided with one or more vents 3400.

The patient interface 3000 may include a positioning and ising structure 3300 that includes conduits 3301. The conduits 3301 serve two purposes: 1) to position and stabilize the patient interface 3000 on the patient’s head in a therapeutically effective position during use and 2) to provide the pressurized, breathable gas to the plenum chamber 3200. As such, the conduits 3301 may be constructed of a le, biocompatible material and may also form a hollow structure. The conduits 3301 may be connected to the plenum chamber 3200 with clips 3303 to provide a tic connection therebetween. The conduits 3301 may also include strap connectors 3302 to connect to a strap (not shown) that passes behind the patient’s head in use. The conduits 3301 may also include flexible portions 3304 that provide flexibility to the conduits 3301 to accommodate different sizes and shapes of patient heads. The patient interface 3000 includes an elbow connector 3305 to connect the decoupling structure 3500. The elbow connector 3305 may be hollow to allow gas from the conduit 4170 to pass through the decoupling ure 3500, through the elbow connector 3305, and into the conduits 3301.

Figs. 12A to 12E show this patient interface 3000 on a t. A strap 3306 may be joined to the strap connectors 3302 to secure the patient interface 3000 in a desired sealing position for therapy.

Further description of exemplary patient interfaces 3000, utes of which may be applied to the present technology, is ed by International Application No. , which is incorporated herein by reference in its entirety. .4 RPT DEVICE An RPT device 4000 in accordance with one aspect of the present technology comprises ical, pneumatic, and/or electrical components and is ured to execute one or more algorithms. The RPT device 4000 may be ResMed Ref: Z3 configured to generate a flow of air for delivery to a patient’s airways, such as to treat one or more of the respiratory ions described elsewhere in the present document.

In one form, the RPT device 4000 is constructed and arranged to be capable of delivering a flow of air in a range of -20 L/min to +150 L/min while maintaining a positive pressure of at least 6 cmH2O, or at least 10cmH2O, or at least cmH2O.

The RPT device may have an al g 4010, formed in two parts, an upper portion 4012 and a lower portion 4014. Furthermore, the external g 4010 may include one or more panel(s) 4015. The RPT device 4000 comprises a chassis 4016 that supports one or more internal components of the RPT device 4000.

The RPT device 4000 may include a handle 4018.

The pneumatic path of the RPT device 4000 may comprise one or more air path items, e.g., an inlet air filter 4112, an inlet muffler 4122, a pressure generator 4140 capable of supplying air at positive pressure (e.g., a blower 4142), an outlet muffler 4124 and one or more transducers 4270, such as pressure sensors and flow rate sensors.

One or more of the air path items may be located within a removable unitary structure which will be ed to as a pneumatic block 4020. The pneumatic block 4020 may be located within the external housing 4010. In one form a pneumatic block 4020 is supported by, or formed as part of the chassis 4016.

The RPT device 4000 may have an electrical power supply 4210, one or more input s 4220, a central controller, a therapy device controller, a pressure generator 4140, one or more protection circuits, memory, transducers 4270, data communication interface, and one or more output devices. Electrical components 4200 may be mounted on a single d Circuit Board Assembly (PCBA) 4202. In an alternative form, the RPT device 4000 may include more than one PCBA 4202.

ResMed Ref: P1218NZ3 .4.1 RPT device ical & pneumatic components An RPT device may comprise one or more of the ing components in an integral unit. In an alternative form, one or more of the following ents may be d as tive separate units. .4.1.1 Air (s) An RPT device in accordance with one form of the present technology may include an air filter 4110, or a plurality of air filters 4110.

In one form, an inlet air filter 4112 is located at the beginning of the pneumatic path upstream of a pressure generator 4140.

In one form, an outlet air filter 4114, for example an antibacterial filter, is located between an outlet of the pneumatic block 4020 and a patient interface 3000. .4.1.2 Muffler(s) An RPT device in accordance with one form of the present technology may include a muffler 4120, or a plurality of mufflers 4120.

In one form of the present technology, an inlet muffler 4122 is located in the pneumatic path upstream of a pressure generator 4140.

In one form of the present technology, an outlet muffler 4124 is located in the pneumatic path between the pressure generator 4140 and a t interface 3000. .4.1.3 Pressure generator In one form of the present technology, a pressure generator 4140 for producing a flow, or a supply, of air at positive pressure is a controllable blower 4142.

For example the blower 4142 may e a brushless DC motor 4144 with one or more impellers housed in a volute. The blower may be capable of delivering a supply of air, for example at a rate of up to about 120 litres/minute, at a positive pressure in a range from about 4 cmH2O to about 20 cmH2O, or in other forms up to about 30 cmH2O. The blower may be as described in any one of the following patents or patent applications the contents of which are incorporated herein by reference in their ResMed Ref: P1218NZ3 entirety: U.S. Patent No. 7,866,944; U.S. Patent No. 8,638,014; U.S. Patent No. 8,636,479; and PCT Patent Application Publication No.

The pressure tor 4140 is under the control of the therapy device controller.

In other forms, a pressure tor 4140 may be a piston-driven pump, a pressure tor connected to a high pressure source (e.g. compressed air reservoir), or a bellows. .4.1.4 Transducer(s) Transducers may be internal of the RPT device, or external of the RPT device. External transducers may be located for example on or form part of the air circuit, e.g., the patient interface. External transducers may be in the form of tact sensors such as a Doppler radar movement sensor that transmit or transfer data to the RPT device.

In one form of the present technology, one or more transducers 4270 are d upstream and/or downstream of the pressure generator 4140. The one or more transducers 4270 may be constructed and arranged to generate signals representing properties of the flow of air such as a flow rate, a pressure or a temperature at that point in the pneumatic path.

In one form of the present technology, one or more transducers 4270 may be d proximate to the patient interface 3000.

In one form, a signal from a transducer 4270 may be filtered, such as by ss, high-pass or band-pass filtering. .4.1.4.1 Flow rate sensor A flow rate sensor in accordance with the present technology may be based on a ential pressure transducer, for example, an SDP600 Series differential pressure transducer from SENSIRION.

ResMed Ref: P1218NZ3 In one form, a signal representing a flow rate from the flow rate sensor is received by the l controller. .4.1.4.2 Pressure sensor A pressure sensor in accordance with the present technology is located in fluid communication with the pneumatic path. An example of a le pressure sensor is a transducer from the HONEYWELL ASDX series. An alternative suitable pressure sensor is a transducer from the NPA Series from GENERAL ELECTRIC.

In one form, a signal from the pressure sensor is received by the central controller. .4.1.4.3 Motor speed transducer In one form of the t technology a motor speed transducer is used to determine a rotational ty of the motor 4144 and/or the blower 4142. A motor speed signal from the motor speed ucer may be provided to the therapy device controller. The motor speed transducer may, for example, be a speed sensor, such as a Hall effect sensor. .4.1.5 Anti-spill back valve In one form of the present technology, an anti-spill back valve 4160 is located between the humidifier 5000 and the pneumatic block 4020. The anti-spill back valve is constructed and arranged to reduce the risk that water will flow am from the fier 5000, for example to the motor 4144. .4.2 RPT device electrical components .4.2.1 Power supply A power supply 4210 may be located internal or external of the external housing 4010 of the RPT device 4000.

In one form of the present technology, power supply 4210 provides electrical power to the RPT device 4000 only. In another form of the present ResMed Ref: P1218NZ3 technology, power supply 4210 provides electrical power to both RPT device 4000 and humidifier 5000. .4.2.2 Input devices In one form of the present technology, an RPT device 4000 includes one or more input devices 4220 in the form of buttons, switches or dials to allow a person to interact with the device. The buttons, switches or dials may be physical devices, or software devices accessible via a touch screen. The buttons, switches or dials may, in one form, be physically connected to the external housing 4010, or may, in another form, be in ss communication with a receiver that is in electrical connection to the central ller.

In one form, the input device 4220 may be constructed and ed to allow a person to select a value and/or a menu option. .4.2.3 Central controller In one form of the present technology, the central controller is one or a plurality of processors le to control an RPT device 4000.

Suitable sors may include an x86 INTEL processor, a processor based on ARM® Cortex®-M processor from ARM Holdings such as an STM32 series microcontroller from ST LECTRONIC. In certain alternative forms of the present technology, a 32-bit RISC CPU, such as an STR9 series microcontroller from ST MICROELECTRONICS or a 16-bit RISC CPU such as a processor from the MSP430 family of microcontrollers, manufactured by TEXAS MENTS may also be suitable.

In one form of the present technology, the central controller is a ted electronic circuit.

In one form, the central controller is an ation-specific integrated circuit. In another form, the central controller comprises discrete electronic components.

ResMed Ref: P1218NZ3 The l controller may be configured to receive input signal(s) from one or more transducers 4270, one or more input devices 4220, and the humidifier 5000.

The l ller may be configured to provide output signal(s) to one or more of an output device, a therapy device controller, a data communication interface, and the humidifier 5000.

In some forms of the t technology, the central controller is configured to implement the one or more methodologies described herein, such as the one or more algorithms expressed as computer programs stored in a non-transitory computer readable storage medium, such as memory. In some forms of the present technology, the central controller may be integrated with an RPT device 4000.

However, in some forms of the present technology, some methodologies may be performed by a remotely located device. For example, the remotely located device may determine control settings for a ventilator or detect respiratory related events by analysis of stored data such as from any of the sensors described herein. .5 AIR CIRCUIT An air circuit 4170 in accordance with an aspect of the present technology is a conduit or a tube constructed and arranged to allow, in use, a flow of air to travel n two components such as RPT device 4000 and the patient interface 3000.

In particular, the air circuit 4170 may be in fluid connection with the outlet of the pneumatic block 4020 and the patient interface. The air t may be referred to as an air delivery tube. In some cases there may be separate limbs of the t for inhalation and exhalation. In other cases a single limb is used.

In some forms, the air circuit 4170 may comprise one or more heating elements configured to heat air in the air circuit, for example to maintain or raise the ature of the air. The heating element may be in a form of a heated wire circuit, and may comprise one or more transducers, such as temperature s. In one form, the heated wire circuit may be helically wound around the axis of the air circuit 4170.

The g element may be in communication with a controller such as a central ResMed Ref: P1218NZ3 controller. One example of an air circuit 4170 comprising a heated wire circuit is described in United States Patent 8,733,349, which is incorporated herewithin in its entirety by reference. .5.1 Oxygen delivery In one form of the present technology, supplemental oxygen 4180 is delivered to one or more points in the pneumatic path, such as am of the pneumatic block 4020, to the air t 4170 and/or to the patient interface 3000. .6 HUMIDIFIER .6.1 Humidifier overview In one form of the present technology there is provided a humidifier 5000 (e.g. as shown in Fig. 5A) to change the absolute humidity of air or gas for delivery to a patient relative to ambient air. Typically, the fier 5000 is used to increase the absolute humidity and increase the temperature of the flow of air (relative to ambient air) before delivery to the patient’s airways.

The humidifier 5000 may comprise a humidifier reservoir 5110, a humidifier inlet 5002 to receive a flow of air, and a humidifier outlet 5004 to deliver a humidified flow of air. In some forms, as shown in Fig. 5A and Fig. 5B, an inlet and an outlet of the humidifier reservoir 5110 may be the humidifier inlet 5002 and the humidifier outlet 5004 respectively. The humidifier 5000 may further comprise a humidifier base 5006, which may be adapted to e the humidifier reservoir 5110 and comprise a heating element 5240. .6.2 Humidifier ents .6.2.1 Water oir According to one arrangement, the humidifier 5000 may comprise a water reservoir 5110 ured to hold, or retain, a volume of liquid (e.g. water) to be evaporated for humidification of the flow of air. The water oir 5110 may be configured to hold a predetermined maximum volume of water in order to provide adequate humidification for at least the duration of a respiratory therapy session, such ResMed Ref: P1218NZ3 as one evening of sleep. Typically, the reservoir 5110 is configured to hold l d millilitres of water, e.g. 300 itres (ml), 325 ml, 350 ml or 400 ml. In other forms, the humidifier 5000 may be configured to e a supply of water from an external water source such as a building’s water supply system.

According to one aspect, the water reservoir 5110 is configured to add humidity to a flow of air from the RPT device 4000 as the flow of air travels therethrough. In one form, the water reservoir 5110 may be configured to encourage the flow of air to travel in a tortuous path through the reservoir 5110 while in contact with the volume of water therein.

According to one form, the oir 5110 may be removable from the humidifier 5000, for example in a lateral direction as shown in Fig. 5A and Fig. 5B.

The reservoir 5110 may also be configured to discourage egress of liquid therefrom, such as when the reservoir 5110 is displaced and/or rotated from its normal, working orientation, such as through any apertures and/or in between its subcomponents.

As the flow of air to be humidified by the humidifier 5000 is typically pressurised, the reservoir 5110 may also be configured to prevent losses in pneumatic re through leak and/or flow impedance. .6.2.2 Conductive portion According to one arrangement, the reservoir 5110 comprises a conductive portion 5120 configured to allow efficient transfer of heat from the heating element 5240 to the volume of liquid in the oir 5110. In one form, the conductive portion 5120 may be arranged as a plate, although other shapes may also be suitable.

All or a part of the conductive portion 5120 may be made of a thermally tive material such as aluminium (e.g. approximately 2 mm thick, such as 1 mm, 1.5 mm, 2.5 mm or 3 mm), another heat conducting metal or some plastics. In some cases, suitable heat conductivity may be achieved with less tive materials of suitable geometry.

ResMed Ref: P1218NZ3 .6.2.3 Humidifier reservoir dock In one form, the humidifier 5000 may comprise a humidifier reservoir dock 5130 (as shown in Fig. 5B) configured to receive the humidifier reservoir 5110.

In some arrangements, the humidifier reservoir dock 5130 may comprise a g feature such as a locking lever 5135 configured to retain the reservoir 5110 in the humidifier reservoir dock 5130. .6.2.4 Water level indicator The humidifier oir 5110 may comprise a water level indicator 5150 as shown in Fig. 5A-5B. In some forms, the water level indicator 5150 may provide one or more indications to a user such as the patient 1000 or a care giver regarding a quantity of the volume of water in the humidifier oir 5110. The one or more indications provided by the water level indicator 5150 may include an indication of a maximum, predetermined volume of water, any portions thereof, such as 25%, 50% or 75% or volumes such as 200 ml, 300 ml or 400ml. .6.2.5 g element A heating element 5240 may be provided to the humidifier 5000 in some cases to e a heat input to one or more of the volume of water in the humidifier reservoir 5110 and/or to the flow of air. The heating element 5240 may comprise a heat generating component such as an electrically resistive heating track. One suitable example of a heating element 5240 is a layered heating t such as one described in the PCT Patent Application Publication No. incorporated th by reference in its entirety.

In some forms, the heating element 5240 may be ed in the humidifier base 5006 where heat may be provided to the humidifier reservoir 5110 primarily by conduction as shown in Fig. 5B. .7 BREATHING WAVEFORMS Fig. 6 shows a model typical breath waveform of a person while sleeping.

The horizontal axis is time, and the vertical axis is respiratory flow rate. While the parameter values may vary, a typical breath may have the following approximate ResMed Ref: P1218NZ3 values: tidal volume, Vt, 0.5L, inhalation time, Ti, 1.6s, peak inspiratory flow rate, Qpeak, 0.4 L/s, exhalation time, Te, 2.4s, peak tory flow rate, Qpeak, -0.5 L/s.

The total duration of the breath, Ttot, is about 4s. The person typically breathes at a rate of about 15 breaths per minute (BPM), with Ventilation, Vent, about 7.5 L/min. A typical duty cycle, the ratio of Ti to Ttot, is about 40%. .8 GLOSSARY For the purposes of the present logy disclosure, in certain forms of the present technology, one or more of the following definitions may apply. In other forms of the present technology, alternative tions may apply. .8.1 General Air: In certain forms of the present technology, air may be taken to mean atmospheric air, and in other forms of the present technology air may be taken to mean some other combination of breathable gases, e.g. atmospheric air enriched with oxygen.

Ambient: In certain forms of the present technology, the term ambient will be taken to mean (i) external of the treatment system or patient, and (ii) immediately surrounding the treatment system or patient.

For example, ambient ty with respect to a humidifier may be the humidity of air immediately surrounding the humidifier, e.g. the humidity in the room where a patient is sleeping. Such ambient humidity may be different to the humidity outside the room where a t is ng.

In another example, ambient pressure may be the pressure immediately surrounding or external to the body.

In certain forms, ambient (e.g., acoustic) noise may be considered to be the background noise level in the room where a t is d, other than for example, noise generated by an RPT device or emanating from a mask or patient ace. Ambient noise may be generated by sources outside the room.

ResMed Ref: P1218NZ3 Automatic Positive Airway Pressure (APAP) y: CPAP therapy in which the treatment pressure is automatically adjustable, e.g. from breath to breath, between minimum and maximum limits, depending on the presence or absence of tions of SDB events.

Continuous Positive Airway Pressure (CPAP) y: Respiratory re therapy in which the treatment pressure is approximately nt through a atory cycle of a patient. In some forms, the pressure at the entrance to the airways will be slightly higher during tion, and slightly lower during inhalation.

In some forms, the pressure will vary between different respiratory cycles of the patient, for example, being increased in se to detection of tions of partial upper airway obstruction, and decreased in the e of indications of partial upper airway obstruction.

Flow rate: The volume (or mass) of air delivered per unit time. Flow rate may refer to an instantaneous quantity. In some cases, a reference to flow rate will be a reference to a scalar quantity, namely a quantity having magnitude only. In other cases, a reference to flow rate will be a reference to a vector ty, namely a quantity having both magnitude and direction. Flow rate may be given the symbol Q.

‘Flow rate’ is sometimes shortened to simply ‘flow’ or ‘airflow’.

In the example of patient respiration, a flow rate may be nominally positive for the inspiratory n of a breathing cycle of a patient, and hence negative for the expiratory portion of the breathing cycle of a patient. Total flow rate, Qt, is the flow rate of air leaving the RPT device. Vent flow rate, Qv, is the flow rate of air leaving a vent to allow washout of exhaled gases. Leak flow rate, Ql, is the flow rate of leak from a patient interface system or elsewhere. Respiratory flow rate, Qr, is the flow rate of air that is received into the patient's respiratory system.

Humidifier: The word humidifier will be taken to mean a humidifying apparatus constructed and arranged, or configured with a physical structure to be capable of providing a therapeutically beneficial amount of water (H2O) vapour to a flow of air to ameliorate a medical respiratory condition of a patient.

ResMed Ref: P1218NZ3 Leak: The word leak will be taken to be an unintended flow of air. In one example, leak may occur as the result of an incomplete seal between a mask and a patient's face. In r example leak may occur in a swivel elbow to the t.

Noise, conducted (acoustic): Conducted noise in the present document refers to noise which is carried to the patient by the pneumatic path, such as the air circuit and the patient interface as well as the air therein. In one form, conducted noise may be fied by measuring sound pressure levels at the end of an air circuit.

Noise, radiated (acoustic): Radiated noise in the present nt refers to noise which is carried to the patient by the ambient air. In one form, radiated noise may be quantified by measuring sound power/pressure levels of the object in on according to ISO 3744.

Noise, vent (acoustic): Vent noise in the present document refers to noise which is generated by the flow of air through any vents such as vent holes of the patient interface.

Patient: A person, whether or not they are suffering from a respiratory condition.

Pressure: Force per unit area. Pressure may be expressed in a range of units, including cmH2O, g-f/cm2 and hectopascal. 1 cmH2O is equal to 1 g-f/cm2 and is approximately 0.98 hectopascal. In this specification, unless otherwise , pressure is given in units of cmH2O.

The pressure in the t interface is given the symbol Pm, while the treatment pressure, which ents a target value to be achieved by the mask pressure Pm at the current instant of time, is given the symbol Pt.

Respiratory Pressure Therapy (RPT): The application of a supply of air to an entrance to the airways at a treatment pressure that is typically positive with respect to atmosphere.

ResMed Ref: P1218NZ3 Ventilator: A mechanical device that provides pressure support to a patient to perform some or all of the work of breathing. .8.1.1 Materials Silicone or Silicone Elastomer: A synthetic rubber. In this ication, a reference to silicone is a reference to liquid silicone rubber (LSR) or a ssion moulded silicone rubber (CMSR). One form of commercially available 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 to the contrary, an exemplary form of LSR has a Shore A (or Type A) indentation hardness in the range of about 35 to about 45 as measured using ASTM D2240. (Year? Required?) rbonate: a plastic r of nol-A ate. .8.1.2 Mechanical properties Resilience: Ability of a material to absorb energy when deformed elastically and to release the energy upon ing.

Resilient: Will release substantially all of the energy when unloaded.

Includes e.g. certain silicones, and thermoplastic elastomers.

Hardness: The ability of a material per se to resist deformation (e.g. described by a Young’s Modulus, or an indentation hardness scale measured on a standardised sample size).

• ‘Soft’ materials may e silicone or thermo-plastic elastomer (TPE), and may, e.g. readily deform under finger pressure.

• ‘Hard’ materials may include polycarbonate, polypropylene, steel or aluminium, and may not e.g. readily deform under finger pressure. ess (or rigidity) of a structure or component: The ability of the structure or component to resist deformation in response to an applied load. The load may be a force or a moment, e.g. compression, tension, bending or torsion. The structure or component may offer different resistances in different directions.

ResMed Ref: P1218NZ3 Floppy structure or component: A ure or component that will change shape, e.g. bend, when caused to support its own , within a relatively short period of time such as 1 .

Rigid structure or component: A structure or component that will not substantially change shape when subject to the loads typically encountered in use. An example of such a use may be setting up and maintaining a patient interface in sealing relationship with an entrance to a patient's airways, e.g. at a load of approximately 20 to 30 cmH2O pressure.

As an example, an I-beam may comprise a different bending stiffness (resistance to a bending load) in a first direction in comparison to a second, orthogonal direction. In another example, a structure or component may be floppy in a first direction and rigid in a second direction. .8.2 atory cycle Apnea: According to some definitions, an apnea is said to have occurred when flow falls below a predetermined threshold for a on, e.g. 10 seconds. An obstructive apnea will be said to have occurred when, despite patient effort, some obstruction of the airway does not allow air to flow. A central apnea will be said to have occurred when an apnea is ed that is due to a reduction in breathing effort, or the absence of breathing effort, despite the airway being patent. A mixed apnea occurs when a reduction or absence of breathing effort des with an obstructed airway.

Breathing rate: The rate of spontaneous respiration of a t, usually measured in breaths per minute.

Duty cycle: The ratio of inhalation time, Ti to total breath time, Ttot.

Effort (breathing): The work done by a spontaneously ing person attempting to breathe.

Expiratory portion of a breathing cycle: The period from the start of expiratory flow to the start of inspiratory flow.

ResMed Ref: P1218NZ3 Flow limitation: Flow limitation will be taken to be the state of affairs in a patient's respiration where an increase in effort by the t does not give rise to a corresponding increase in flow. Where flow limitation occurs during an atory n of the breathing cycle it may be described as inspiratory flow limitation.

Where flow limitation occurs during an expiratory portion of the breathing cycle it may be described as expiratory flow limitation.

Types of flow limited atory waveforms: (i) Flattened: Having a rise followed by a relatively flat portion, followed by a fall. (ii) M-shaped: Having two local peaks, one at the leading edge, and one at the trailing edge, and a relatively flat portion between the two peaks. (iii) Chair-shaped: Having a single local peak, the peak being at the leading edge, followed by a relatively flat portion. (iv) Reverse-chair shaped: Having a relatively flat portion followed by single local peak, the peak being at the trailing edge.

Hypopnea: According to some definitions, a hypopnea is taken to be a reduction in flow, but not a cessation of flow. In one form, a ea may be said to have occurred when there is a reduction in flow below a threshold rate for a duration.

A central hypopnea will be said to have ed when a hypopnea is detected that is due to a reduction in breathing effort. In one form in adults, either of the following may be regarded as being hypopneas: (i) a 30% ion in patient breathing for at least 10 seconds plus an associated 4% desaturation; or (ii) a reduction in patient breathing (but less than 50%) for at least 10 seconds, with an associated desaturation of at least 3% or an arousal. nea: An increase in flow to a level higher than normal.

ResMed Ref: P1218NZ3 Inspiratory portion of a breathing cycle: The period from the start of inspiratory flow to the start of expiratory flow will be taken to be the inspiratory n of a breathing cycle.

Patency (airway): The degree of the airway being open, or the extent to which the airway is open. A patent airway is open. Airway patency may be quantified, for example with a value of one (1) being patent, and a value of zero (0), being closed (obstructed).

Positive End-Expiratory Pressure (PEEP): The pressure above atmosphere in the lungs that exists at the end of expiration.

Peak flow rate (Qpeak): The maximum value of flow rate during the inspiratory portion of the respiratory flow rm.

Respiratory flow rate, t airflow rate, respiratory airflow rate (Qr): These terms may be tood to refer to the RPT device’s estimate of atory flow rate, as opposed to "true respiratory flow rate" or "true respiratory flow rate", which is the actual respiratory flow rate experienced by the patient, usually expressed in litres per minute.

Tidal volume (Vt): The volume of air inhaled or exhaled during normal breathing, when extra effort is not applied. (inhalation) Time (Ti): The duration of the inspiratory portion of the respiratory flow rate waveform. (exhalation) Time (Te): The duration of the expiratory portion of the atory flow rate waveform. (total) Time (Ttot): The total duration between the start of one inspiratory portion of a respiratory flow rate waveform and the start of the following inspiratory portion of the respiratory flow rate waveform.

ResMed Ref: P1218NZ3 Typical recent ventilation: The value of ventilation around which recent values of ventilation Vent over some predetermined ale tend to cluster, that is, a measure of the central tendency of the recent values of ventilation.

Upper airway obstruction (UAO): includes both partial and total upper airway obstruction. This may be associated with a state of flow limitation, in which the flow rate increases only slightly or may even decrease as the pressure ence across the upper airway increases (Starling resistor behaviour). ation (Vent): A measure of a rate of gas being ged by the patient’s respiratory system. Measures of ventilation may include one or both of inspiratory and expiratory flow, per unit time. When expressed as a volume per minute, this quantity is often referred to as "minute ventilation". Minute ventilation is mes given simply as a volume, understood to be the volume per minute. .8.3 Ventilation Adaptive Servo-Ventilator (ASV): A servo-ventilator that has a changeable, rather than fixed target ation. The changeable target ventilation may be d from some characteristic of the patient, for example, a respiratory characteristic of the patient.

Backup rate: A parameter of a ventilator that establishes the minimum breathing rate (typically in number of breaths per minute) that the ator will deliver to the patient, if not triggered by spontaneous respiratory effort.

Cycled: The termination of a ventilator's inspiratory phase. When a ventilator delivers a breath to a spontaneously breathing patient, at the end of the inspiratory portion of the ing cycle, the ventilator is said to be cycled to stop delivering the breath.

Expiratory positive airway pressure (EPAP): a base pressure, to which a pressure varying within the breath is added to produce the desired mask pressure which the ventilator will attempt to achieve at a given time.

ResMed Ref: P1218NZ3 End expiratory pressure (EEP): Desired mask re which the ventilator will attempt to achieve at the end of the expiratory portion of the breath. If the pressure waveform template () is zero-valued at the end of expiration, i.e. () = 0 when  = 1, the EEP is equal to the EPAP.

Inspiratory positive airway pressure (IPAP): m desired mask pressure which the ventilator will attempt to achieve during the inspiratory portion of the breath.

Pressure support: A number that is indicative of the increase in pressure during ventilator inspiration over that during ventilator expiration, and generally means the ence in pressure between the maximum value during inspiration and the base pressure (e.g., PS = IPAP – EPAP). In some ts pressure support means the difference which the ventilator aims to e, rather than what it actually achieves.

Servo-ventilator: A ventilator that measures patient ventilation, has a target ventilation, and which adjusts the level of pressure support to bring the patient ation towards the target ventilation.

Spontaneous/Timed (S/T): A mode of a ator or other device that attempts to detect the initiation of a breath of a neously breathing patient. If however, the device is unable to detect a breath within a predetermined period of time, the device will automatically initiate delivery of the .

Swing: Equivalent term to pressure t.

Triggered: When a ventilator delivers a breath of air to a spontaneously breathing patient, it is said to be triggered to do so at the initiation of the respiratory n of the breathing cycle by the patient's efforts.

Typical recent ventilation: The typical recent ventilation Vtyp is the value around which recent measures of ventilation over some predetermined timescale tend to cluster. For example, a measure of the central tendency of the measures of ventilation over recent history may be a suitable value of a typical recent ventilation.

ResMed Ref: P1218NZ3 .8.4 Anatomy .8.4.1 Anatomy of the face Ala: the external outer wall or "wing" of each nostril (plural: alar) Alare: The most lateral point on the nasal ala.

Alar curvature (or alar crest) point: The most posterior point in the curved base line of each ala, found in the crease formed by the union of the ala with the cheek.

Auricle: The whole external visible part of the ear. (nose) Bony framework: The bony ork of the nose comprises the nasal bones, the frontal process of the maxillae and the nasal part of the frontal bone. (nose) Cartilaginous framework: The cartilaginous framework of the nose comprises the , l, major and minor cartilages.

Columella: the strip of skin that separates the nares and which runs from the pronasale to the upper lip.

Columella angle: The angle between the line drawn through the nt of the nostril re and a line drawn perpendicular to the Frankfort horizontal while intersecting subnasale.

Frankfort horizontal plane: A line extending from the most inferior point of the orbital margin to the left n. The tragion is the deepest point in the notch superior to the tragus of the auricle.

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

Lateral nasal cartilage: A lly triangular plate of cartilage. Its superior margin is attached to the nasal bone and frontal process of the maxilla, and its inferior margin is connected to the greater alar cartilage.

ResMed Ref: P1218NZ3 Greater alar cartilage: A plate of cartilage lying below the lateral nasal cartilage. It is curved around the anterior part of the naris. Its posterior end is connected to the frontal process of the maxilla by a tough fibrous membrane containing three or four minor cartilages of the ala.

Nares (Nostrils): imately ellipsoidal apertures forming the entrance to the nasal . The singular form of nares is naris (nostril). The nares are separated by the nasal .

Naso-labial sulcus or Naso-labial fold: The skin fold or groove that runs from each side of the nose to the corners of the mouth, separating the cheeks from the upper lip.

Naso-labial angle: The angle between the columella and the upper lip, while intersecting subnasale.

Otobasion inferior: The lowest point of attachment of the auricle to the skin of the face.

Otobasion superior: The highest point of attachment of the auricle to the skin of the face.

Pronasale: the most protruded point or tip of the nose, which can be identified in lateral view of the rest of the portion of the head. um: the midline groove that runs from lower border of the nasal septum to the top of the lip in the upper lip region.

Pogonion: Located on the soft tissue, the most anterior midpoint of the chin.

Ridge ): The nasal ridge is the midline ence of the nose, extending from the Sellion to the Pronasale.

Midsagittal plane: A al plane that passes from anterior (front) to posterior (rear) dividing the body into right and left halves.

ResMed Ref: P1218NZ3 Sellion: Located on the soft tissue, the most concave point overlying the area of the frontonasal suture.

Septal cartilage (nasal): The nasal septal cartilage forms part of the septum and divides the front part of the nasal .

Subalare: The point at the lower margin of the alar base, where the alar base joins with the skin of the superior (upper) lip.

Subnasal point: Located on the soft tissue, the point at which the columella merges with the upper lip in the midsagittal plane.

Supramenton: The point of greatest concavity in the midline of the lower lip between labrale inferius and soft tissue pogonion .8.4.2 Anatomy of the skull Frontal bone: The frontal bone includes a large vertical portion, the squama frontalis, corresponding to the region known as the ad.

Mandible: The mandible forms the lower jaw. The mental protuberance is the bony protuberance of the jaw that forms the chin.

Maxilla: The a forms the upper jaw and is located above the mandible and below the orbits. The frontal process of the maxilla projects upwards by the side of the nose, and forms part of its lateral boundary.

Nasal bones: The nasal bones are two small oblong bones, g in size and form in different individuals; they are placed side by side at the middle and upper part of the face, and form, by their on, the "bridge" of the nose.

Nasion: The intersection of the frontal bone and the two nasal bones, a depressed area directly between the eyes and superior to the bridge of the nose.

Occipital bone: The occipital bone is situated at the back and lower part of the cranium. It es an oval aperture, the n magnum, through which the ResMed Ref: P1218NZ3 l cavity communicates with the vertebral canal. The curved plate behind the foramen magnum is the squama occipitalis.

Orbit: The bony cavity in the skull to contain the eyeball.

Parietal bones: The al bones are the bones that, when joined together, form the roof and sides of the cranium.

Temporal bones: The temporal bones are situated on the bases and sides of the skull, and support that part of the face known as the temple.

Zygomatic bones: The face includes two zygomatic bones, located in the upper and l parts of the face and forming the prominence of the cheek. .8.4.3 Anatomy of the respiratory system Diaphragm: A sheet of muscle that s across the bottom of the rib cage. The diaphragm separates the thoracic cavity, containing the heart, lungs and ribs, from the abdominal cavity. As the diaphragm contracts the volume of the ic cavity increases and air is drawn into the lungs.

Larynx: The larynx, or voice box houses the vocal folds and connects the inferior part of the pharynx (hypopharynx) with the trachea.

Lungs: The organs of respiration in humans. The conducting zone of the lungs contains the trachea, the bronchi, the bronchioles, and the terminal bronchioles.

The respiratory zone contains the respiratory bronchioles, the alveolar ducts, and the alveoli.

Nasal cavity: The nasal cavity (or nasal fossa) is a large air filled space above and behind the nose in the middle of the face. The nasal cavity is d in two by a vertical fin called the nasal septum. On the sides of the nasal cavity are three horizontal outgrowths called nasal conchae (singular "concha") or turbinates. To the front of the nasal cavity is the nose, while the back blends, via the choanae, into the nasopharynx.

ResMed Ref: P1218NZ3 Pharynx: The part of the throat situated immediately inferior to (below) the nasal cavity, and superior to the oesophagus and larynx. The pharynx is conventionally divided into three sections: the nasopharynx (epipharynx) (the nasal part of the x), the oropharynx (mesopharynx) (the oral part of the pharynx), and the laryngopharynx (hypopharynx). .8.5 Patient interface Anti-asphyxia valve (AAV): The component or sub-assembly of a mask system that, by opening to atmosphere in a failsafe , reduces the risk of excessive CO2 rebreathing by a patient.

Elbow: An elbow is an example of a structure that directs an axis of flow of air travelling therethrough to change direction through an angle. In one form, the angle may be approximately 90 degrees. In another form, the angle may be more, or less than 90 degrees. The elbow may have an approximately ar cross-section. In another form the elbow may have an oval or a rectangular section. In n forms an elbow may be rotatable with respect to a mating component, e.g. about 360 degrees. In certain forms an elbow may be removable from a mating ent, e.g. via a snap connection. In n forms, an elbow may be assembled to a mating component via a one-time snap during manufacture, but not removable by a patient.

Frame: Frame will be taken to mean a mask structure that bears the load of tension between two or more points of connection with a ar. A mask frame may be a rtight load bearing structure in the mask. However, some forms of mask frame may also be air-tight.

Functional dead space: (description to be inserted here) Headgear: Headgear will be taken to mean a form of positioning and stabilizing ure designed for use on a head. For example the headgear may comprise a collection of one or more struts, ties and stiffeners configured to locate and retain a patient interface in position on a patient’s face for delivery of respiratory therapy. Some ties are formed of a soft, flexible, elastic material such as a laminated composite of foam and fabric.

ResMed Ref: P1218NZ3 Membrane: Membrane will be taken to mean a typically thin element that has, preferably, substantially no resistance to bending, but has resistance to being stretched.

Plenum chamber: a mask plenum r will be taken to mean a portion of a patient interface having walls at least partially enclosing a volume of space, the volume having air therein pressurised above atmospheric pressure in use. A shell may form part of the walls of a mask plenum chamber.

Seal: May be a noun form ("a seal") which refers to a structure, or a verb form ("to seal") which refers to the effect. Two elements may be constructed and/or arranged to ‘seal’ or to effect ‘sealing’ therebetween without requiring a separate ‘seal’ element per se.

Shell: A shell will be taken to mean a curved, relatively thin structure having g, tensile and ssive stiffness. For example, a curved structural wall of a mask may be a shell. In some forms, a shell may be d. In some forms a shell may be airtight. In some forms a shell may not be airtight.

Stiffener: A stiffener will be taken to mean a structural component designed to increase the bending resistance of another component in at least one direction.

Strut: A strut will be taken to be a structural component ed to se the compression resistance of another component in at least one direction.

Swivel (noun): A subassembly of components configured to rotate about a common axis, preferably independently, preferably under low torque. In one form, the swivel may be constructed to rotate through an angle of at least 360 degrees. In another form, the swivel may be constructed to rotate h an angle less than 360 degrees. When used in the context of an air delivery conduit, the sub-assembly of components preferably comprises a matched pair of rical conduits. There may be little or no leak flow of air from the swivel in use.

Tie (noun): A ure designed to resist tension.

ResMed Ref: P1218NZ3 Vent: (noun): A structure that allows a flow of air from an or of the mask, or conduit, to ambient air for clinically effective washout of exhaled gases. For example, a clinically effective washout may involve a flow rate of about 10 litres per minute to about 100 litres per minute, depending on the mask design and treatment pressure. .8.6 Shape of structures Products in accordance with the present technology may comprise one or more three-dimensional mechanical structures, for example a mask cushion or an impeller. The three-dimensional structures may be bounded by two-dimensional surfaces. These surfaces may be distinguished using a label to describe an associated surface orientation, location, function, or some other teristic. For e a structure may comprise one or more of an anterior surface, a posterior surface, an interior e and an exterior surface. In another example, a seal-forming structure may comprise a face-contacting (e.g. outer) surface, and a separate non-facecontacting (e.g. underside or inner) surface. In another example, a ure may comprise a first surface and a second surface.

To tate describing the shape of the three-dimensional structures and the surfaces, we first consider a cross-section through a surface of the structure at a point, p. See Fig. 3B to Fig. 3F, which illustrate examples of cross-sections at point p on a surface, and the ing plane curves. Figs. 3B to 3F also rate an outward normal vector at p. The d normal vector at p points away from the surface. In some es we describe the surface from the point of view of an imaginary small person standing upright on the surface. .8.6.1 Curvature in one dimension The curvature of a plane curve at p may be described as having a sign (e.g. positive, negative) and a magnitude (e.g. 1/radius of a circle that just touches the curve at p).

Positive curvature: If the curve at p turns s the outward normal, the curvature at that point will be taken to be positive (if the imaginary small person ResMed Ref: P1218NZ3 leaves the point p they must walk uphill). See Fig. 3B (relatively large positive curvature compared to Fig. 3C) and Fig. 3C ively small positive curvature compared to Fig. 3B). Such curves are often referred to as concave.

Zero curvature: If the curve at p is a straight line, the curvature will be taken to be zero (if the imaginary small person leaves the point p, they can walk on a level, neither up nor down). See Fig. 3D.

Negative curvature: If the curve at p turns away from the outward normal, the ure in that direction at that point will be taken to be negative (if the imaginary small person leaves the point p they must walk downhill). See Fig. 3E (relatively small negative curvature compared to Fig. 3F) and Fig. 3F (relatively large ve curvature compared to Fig. 3E). Such curves are often referred to as convex. .8.6.2 Curvature of two ional surfaces A description of the shape at a given point on a two-dimensional surface in accordance with the present technology may include multiple normal ections.

The multiple cross-sections may cut the surface in a plane that includes the outward normal (a "normal plane"), and each cross-section may be taken in a different direction. Each cross-section results in a plane curve with a corresponding curvature.

The different ures at that point may have the same sign, or a different sign.

Each of the curvatures at that point has a magnitude, e.g. vely small. The plane curves in Figs. 3B to 3F could be examples of such multiple cross-sections at a particular point.

Principal curvatures and directions: The directions of the normal planes where the ure of the curve takes its maximum and minimum values are called the principal directions. In the examples of Fig. 3B to Fig. 3F, the maximum curvature occurs in Fig. 3B, and the m occurs in Fig. 3F, hence Fig. 3B and Fig. 3F are cross sections in the principal directions. The principal curvatures at p are the curvatures in the principal directions.

Region of a surface: A connected set of points on a surface. The set of points in a region may have similar characteristics, e.g. curvatures or signs.

ResMed Ref: P1218NZ3 Saddle region: A region where at each point, the principal curvatures have te signs, that is, one is positive, and the other is negative (depending on the direction to which the imaginary person turns, they may walk uphill or downhill).

Dome region: A region where at each point the principal curvatures have the same sign, e.g. both positive (a "concave dome") or both negative (a "convex dome").

Cylindrical region: A region where one pal curvature is zero (or, for e, zero within manufacturing tolerances) and the other pal ure is non-zero.

Planar region: A region of a surface where both of the pal curvatures are zero (or, for example, zero within manufacturing tolerances).

Edge of a surface: A boundary or limit of a surface or region.

Path: In certain forms of the present technology, ‘path’ will be taken to mean a path in the mathematical – topological sense, e.g. a continuous space curve from f(0) to f(1) on a surface. In certain forms of the present technology, a ‘path’ may be described as a route or course, including e.g. a set of points on a surface. (The path for the ary person is where they walk on the surface, and is ous to a garden path).

Path length: In certain forms of the present technology, ‘path length’ will be taken to mean the distance along the surface from f(0) to f(1), that is, the distance along the path on the surface. There may be more than one path between two points on a surface and such paths may have different path lengths. (The path length for the imaginary person would be the distance they have to walk on the surface along the path).

Straight-line distance: The straight-line distance is the distance between two points on a surface, but without regard to the surface. On planar regions, there would be a path on the surface having the same path length as the straight-line distance between two points on the surface. On non-planar surfaces, there may be no ResMed Ref: P1218NZ3 paths having the same path length as the straight-line distance between two points.

(For the imaginary , the straight-line distance would correspond to the distance ‘as the crow flies’.) .8.6.3 Space curves Space curves: Unlike a plane curve, a space curve does not necessarily lie in any particular plane. A space curve may be closed, that is, having no endpoints. A space curve may be considered to be a one-dimensional piece of three-dimensional space. An imaginary person walking on a strand of the DNA helix walks along a space curve. A typical human left ear comprises a helix, which is a left-hand helix, see Fig. 3Q. A typical human right ear ses a helix, which is a right-hand helix, see Fig. 3R. Fig. 3S shows a right-hand helix. The edge of a structure, e.g. the edge of a membrane or impeller, may follow a space curve. In general, a space curve may be bed by a curvature and a n at each point on the space curve. Torsion is a measure of how the curve turns out of a plane. Torsion has a sign and a magnitude.

The torsion at a point on a space curve may be characterised with reference to the t, normal and binormal s at that point.

Tangent unit vector (or unit tangent vector): For each point on a curve, a vector at the point specifies a direction from that point, as well as a magnitude. A tangent unit vector is a unit vector pointing in the same direction as the curve at that point. If an imaginary person were flying along the curve and fell off her vehicle at a particular point, the direction of the tangent vector is the direction she would be ling.

Unit normal vector: As the imaginary person moves along the curve, this tangent vector itself changes. The unit vector pointing in the same direction that the tangent vector is changing is called the unit principal normal vector. It is perpendicular to the tangent vector.

Binormal unit vector: The binormal unit vector is perpendicular to both the tangent vector and the principal normal vector. Its direction may be determined by a right-hand rule (see e.g. Fig. 3P), or atively by a left-hand rule (Fig. 3O).

ResMed Ref: P1218NZ3 Osculating plane: The plane containing the unit tangent vector and the unit principal normal vector. See s 3O and 3P.

Torsion of a space curve: The torsion at a point of a space curve is the magnitude of the rate of change of the binormal unit vector at that point. It measures how much the curve deviates from the osculating plane. A space curve which lies in a plane has zero torsion. A space curve which deviates a relatively small amount from the osculating plane will have a relatively small ude of torsion (e.g. a gently sloping helical path). A space curve which deviates a relatively large amount from the osculating plane will have a relatively large magnitude of n (e.g. a steeply sloping helical path). With reference to Fig. 3S, since T2>T1, the magnitude of the torsion near the top coils of the helix of Fig. 3S is greater than the ude of the torsion of the bottom coils of the helix of Fig. 3S With reference to the right-hand rule of Fig. 3P, a space curve turning towards the direction of the right-hand binormal may be considered as having a righthand positive torsion (e.g. a right-hand helix as shown in Fig. 3S). A space curve turning away from the direction of the right-hand binormal may be considered as having a right-hand ve torsion (e.g. a left-hand helix).

Equivalently, and with reference to a left-hand rule (see Fig. 3O), a space curve turning towards the direction of the and binormal may be considered as having a left-hand positive n (e.g. a left-hand helix). Hence left-hand positive is equivalent to right-hand negative. See Fig. 3T. .8.6.4 Holes A surface may have a mensional hole, e.g. a hole bounded by a plane curve or by a space curve. Thin structures (e.g. a membrane) with a hole, may be described as having a one-dimensional hole. See for example the one dimensional hole in the surface of structure shown in Fig. 3I, bounded by a plane curve.

A structure may have a two-dimensional hole, e.g. a hole bounded by a e. For e, an inflatable tyre has a two dimensional hole bounded by the interior surface of the tyre. In another example, a bladder with a cavity for air or gel ResMed Ref: P1218NZ3 could have a mensional hole. See for example the cushion of Fig. 3L and the example cross-sections therethrough in Fig. 3M and Fig. 3N, with the interior surface bounding a two dimensional hole indicated. In a yet another example, a conduit may comprise a one-dimension hole (e.g. at its entrance or at its exit), and a two-dimension hole bounded by the inside surface of the t. See also the two dimensional hole through the structure shown in Fig. 3K, bounded by a surface as shown. .9 OTHER REMARKS A portion of the disclosure of this patent document contains material which is subject to ght protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent sure, as it appears in Patent Office patent files or records, but otherwise reserves all copyright rights whatsoever.

Unless the context clearly dictates otherwise and where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit, between the upper and lower limit of that range, 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, which may be independently included in the ening ranges, are also encompassed within the technology, t to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those ed limits are also included in the technology.

Furthermore, where a value or values are stated herein as being implemented as part of the logy, it is understood that such values may be approximated, unless otherwise stated, and such values may be utilized to any suitable significant digit to the extent that a practical technical implementation may permit or require it.

Unless defined otherwise, 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 logy s. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the ResMed Ref: P1218NZ3 present technology, a limited number of the exemplary methods and als are described herein.

When a ular material is identified as being used to construct a component, obvious alternative materials with r ties may be used as a substitute. Furthermore, unless specified to the contrary, any and all components herein described are understood to be capable of being ctured and, as such, may be manufactured together or separately.

It must be noted that as used herein and in the appended claims, the singular forms "a", "an", and "the" include their plural lents, unless the context clearly dictates otherwise.

All publications ned herein are incorporated herein by reference in their entirety to disclose and describe the methods and/or materials which are the subject of those publications. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present logy is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.

The terms "comprises" and "comprising" should be interpreted as ing to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.

The subject headings used in the detailed description are included only for the ease of reference of the reader and should not be used to limit the subject matter found throughout the disclosure or the claims. The subject headings should not be used in construing the scope of the claims or the claim limitations. gh the technology herein has been described with reference to particular examples, it is to be tood that these examples are merely illustrative of the principles and applications of the technology. In some instances, the ResMed Ref: P1218NZ3 terminology and symbols may imply specific details that are not ed to ce the technology. For example, although the terms "first" and "second" may be used, unless otherwise specified, they are not intended to indicate any order but may be utilised to distinguish between distinct elements. rmore, although process steps in the methodologies may be described or illustrated in an order, such an ordering is not required. Those skilled in the art will recognize that such ordering may be modified and/or aspects f may be conducted concurrently or even synchronously.

It is therefore to be understood that numerous modifications may be made to the illustrative examples and that other arrangements may be devised without departing from the spirit and scope of the technology.

ResMed Ref: Z3 .10 REFERENCE SIGNS LIST patient 1000 bed partner 1100 patient interface 3000 seal - g structure 3100 connection region 3102 or opening 3104 posterior opening 3106 anterior tie 3108 support structure 3110 interior surface 3112 patient contacting surface 3114 non-patient contacting surface 3116 edge 3118 chamber 3120 undercushion 3122 seal - forming structure 3130 alar sealing portion 3131 opening 3132 columella engagement portion 3133 ResMed Ref: P1218NZ3 thickened region 3134 undercushion layer 3135 alar sealing portion support 3137 plenum chamber connection portion 3138 outer membrane 3139 superior portion 3140 inferior portion 3141 lateral portion 3142 inwardly curved portion 3144 outwardly curved n 3145 plenum chamber 3200 chord 3210 superior point 3220 or point 3230 positioning and ising structure 3300 conduit 3301 strap connector 3302 clip 3303 flexible portion 3304 elbow connector 3305 ResMed Ref: P1218NZ3 strap 3306 positioning and stabilising structure 3330 rigidiser arm 3331 side strap 3332 crown strap 3333 opening 3334 rear strap 3335 connector 3336 rigidiser arm connector 3337 rigidiser arm connection ring 3338 decoupler connection ring 3339 flexible decoupling structure 3340 plenum chamber tor 3341 rigidiser arm ly 3342 vent 3400 vent holes 3401 decoupling structure 3500 swivel 3501 patient interface connector 3502 connection port 3600 ResMed Ref: P1218NZ3 forehead t 3700 RPT device 4000 external housing 4010 upper portion 4012 portion 4014 panel 4015 chassis 4016 handle 4018 pneumatic block 4020 air filter 4110 inlet air filter 4112 outlet air filter 4114 muffler 4120 inlet muffler 4122 outlet muffler 4124 pressure generator 4140 blower 4142 motor 4144 anti - spill back valve 4160 air circuit 4170 ResMed Ref: P1218NZ3 supplemental oxygen 4180 electrical ents 4200 PCBA 4202 power supply 4210 input device 4220 transducer 4270 humidifier 5000 humidifier inlet 5002 humidifier outlet 5004 humidifier base 5006 reservoir 5110 conductive portion 5120 humidifier reservoir dock 5130 locking lever 5135 water level indicator 5150 heating element 5240 ResMed Ref: P1218NZ3 6

Claims (58)

1. A patient interface for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to the patient’s airways including at least an entrance of a patient’s nares, wherein the patient interface is ured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the patient’s atory cycle, while the patient is sleeping, to ameliorate sleep disordered ing, said patient interface comprising: a seal forming structure to form a seal with the entrance to the patient’s airways including at least the entrance of the patient’s nares; a plenum r pressurised at a pressure above t pressure in use, the seal forming structure ed to the plenum chamber; and a positioning and stabilising structure to maintain the seal forming structure in sealing contact with an area surrounding the entrance to the patient’s airways while maintaining a therapeutic pressure at the entrance to the patient’s airways, wherein the positioning and stabilising structure is connected to the plenum chamber such that forces d on the positioning and stabilising structure by movement of the patient’s head are decoupled from the plenum chamber and the seal forming structure, n the positioning and stabilising structure comprises a rigidiser arm assembly, the rigidiser arm assembly being flexibly attached to the plenum chamber, wherein the rigidiser arm assembly is flexibly attached to a medial, or surface of the plenum chamber.

2. The t interface of claim 1, wherein the rigidiser arm assembly is flexibly attached to the plenum chamber such that in use the rigidiser arm assembly is ResMed Ref: P1218NZ3 movable substantially independently relative to the plenum chamber and the seal forming structure.

3. The patient interface of claim 1 or 2, wherein the rigidiser arm assembly is flexibly ed to the plenum chamber such that movement of the positioning and stabilising structure in use does not disrupt the sealing contact of the seal g structure with the area nding the entrance to the t’s airways.

4. The patient interface of any one of claims 1 to 3, wherein the rigidiser arm assembly is flexibly attached to the plenum chamber with an elastic material.

5. The patient ace of any one of claims 1 to 4, wherein the positioning and stabilising structure comprises a plurality of straps to secure the patient interface on the patient’s head in use by attachment to the rigidiser arm assembly.

6. The patient interface of claim 5, wherein the plurality of straps are only connected to the ser arm assembly.

7. The patient interface of claim 5 or 6, wherein the rigidiser arm assembly further comprises two rigider arms, each of the rigidiser arms configured to pass along one of the patient’s cheeks in use, and each of the rigidiser arms having an opening, wherein the plurality of straps comprises two side straps, each of the side straps configured to connect to one of the rigidiser arms at the opening, and each of the side straps configured to pass below the patient’s eye and above the patient’s ear in use.

8. The patient interface of claim 7, wherein each of the side straps es one of a hook material and a loop material and each of the side straps es a connector of the other of the hook material and the loop material to secure the side straps to the rigidiser arms through each g.

9. The patient interface of any one of claims 5 to 8, n a first strap of the plurality of straps is made of a first material having a first elasticity and a second ResMed Ref: P1218NZ3 strap of the plurality of straps is made of a second material having a second elasticity that is different from the first elasticity.

10. The patient interface of claim 9, wherein each of first al and the second material is one of textile, foam, and breathable neoprene.

11. The patient interface of any one of claims 5 to 10, wherein the plurality of straps comprises a crown strap to engage the patient’s head proximal to the parietal bone and a rear strap to engage the patient’s head proximal to the occipital bone.

12. The patient interface of claim 11, wherein the rear strap is more elastic than the crown strap.

13. The patient interface of any one of claims 1 to 12, wherein the seal forming structure has one opening to e the pressurised gas to both of the patient’s nares or the seal forming structure has two openings such that each of the two openings provide the pressurised gas to a corresponding one of the patient’s nares.

14. The patient interface of any one of claims 1 to 13, wherein the seal forming structure includes two alar sealing portions, each alar g portion being shaped and dimensioned to seal between ponding ones of the patient’s nasal ala and nasolabial sulcus.

15. The patient interface of claim 14, wherein the seal forming structure includes an undercushion shaped and dimensioned to only support an inferior portion of the seal forming structure against the t’s lip superior and the alar sealing ns against corresponding ones of the patient’s nasal ala and bial sulcus.

16. The t interface of claim 15, wherein the seal forming structure and the undercushion are formed from one homogeneous piece of material.

17. The patient interface of claim 15 or 16, wherein the seal forming structure and the ushion are formed from silicone. ResMed Ref: P1218NZ3

18. A patient interface for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to the patient’s airways including at least an ce of a patient’s nares, wherein the patient interface is configured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the patient’s respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing, said patient interface comprising: a seal forming structure to form a seal with the entrance to the patient’s airways including at least the entrance of the t’s nares; a plenum chamber rised at a pressure above ambient pressure in use, the seal forming ure attached to the plenum chamber; and a positioning and stabilising structure to maintain the seal forming structure in sealing contact with an area nding the entrance to the patient’s airways while maintaining a therapeutic re at the entrance to the patient’s airways, wherein the oning and stabilising structure comprises a rigidiser arm assembly that is flexibly connected to the plenum chamber by at least one flexible decoupling structure such that forces imposed on the oning and stabilising structure by movement of the patient’s head are decoupled from the plenum chamber and the seal forming structure, wherein the plenum chamber further comprises a plenum chamber connector and the rigidiser arm assembly comprises a rigidiser arm connection ring, and n the plenum chamber connector and the rigidiser arm connection ring are flexibly connected by the at least one flexible decoupling structure.

19. The patient ace of claim 18, wherein the plenum chamber connector is fixed to a medial, anterior surface of the plenum chamber. ResMed Ref: P1218NZ3

20. The patient interface of claim 18 or 19, wherein the rigidiser arm assembly further comprises two rigider arms, each of the rigidiser arms configured to pass along one of the patient’s cheeks in use, and wherein the rigidiser arm assembly further comprises two rigidiser arm connectors, each of the rigidiser arm connectors connecting a corresponding rigidiser arm to the rigidiser arm connection ring.

21. The patient interface of claim 20, wherein the rigidiser arm connection ring and the two rigidiser arm connectors are formed from one neous piece of a first material.

22. The patient interface of claim 21, wherein each of the rigidiser arms are formed from a second al that is different from the first material.

23. The patient interface of claim 22, wherein the first al is more rigid than the second material.

24. The t interface of any one of claims 20 to 23, wherein each of the rigidiser arms is connected to a corresponding one of the rigidiser arm connectors with a chemical bond or a mechanical interlock.

25. The patient interface of any one of claims 18 to 24, wherein the at least one flexible decoupling structure comprises an elastic material.

26. The t interface of any one of claims 18 to 25, wherein the oning and stabilising structure ses a plurality of straps to secure the patient ace on the patient’s head in use by attachment to the rigidiser arm assembly.

27. The patient interface of claim 26, wherein the plurality of straps are only connected to the rigidiser arm assembly.

28. The t interface of claim 26 or 27, wherein each of the rigidiser arms having an opening, and ResMed Ref: P1218NZ3 wherein the plurality of straps comprises two side straps, each of the side straps configured to t to one of the rigidiser arms at the g, and each of the side straps configured to pass below the patient’s eye and above the patient’s ear in use.

29. The patient interface of claim 28, n each of the side straps includes one of a hook material and a loop material and each of the side straps includes a tor of the other of the hook material and the loop material to secure the side straps to the ser arms through each opening.

30. The patient interface of any one of claims 26 to 29, wherein a first strap of the plurality of straps is made of a first material having a first elasticity and a second strap of the plurality of straps is made of a second material having a second elasticity that is ent from the first elasticity.

31. The patient ace of claim 30, wherein each of first material and the second material is one of e, foam, and breathable neoprene.

32. The patient interface of any one of claims 26 to 31, wherein the plurality of straps comprises a crown strap to engage the patient’s head proximal to the parietal bone and a rear strap to engage the patient’s head proximal to the occipital bone.

33. The t interface of claim 32, wherein the rear strap is more elastic than the crown strap.

34. The patient interface of any one of claims 18 to 33, wherein the seal forming structure has one opening to provide the pressurised gas to both of the patient’s nares or the seal forming structure has two openings such that each of the two openings provide the pressurised gas to a corresponding one of the patient’s nares.

35. The patient interface of any one of claims 18 to 34, wherein the seal forming structure includes two alar sealing portions, each alar sealing portion being shaped and dimensioned to seal between corresponding ones of the patient’s nasal ala and nasolabial sulcus. ResMed Ref: P1218NZ3

36. The patient interface of claim 35, n the seal g structure includes an undercushion shaped and dimensioned to only support an inferior portion of the seal forming structure against the t’s lip superior and the alar sealing portions t ponding ones of the patient’s nasal ala and nasolabial sulcus.

37. The t interface of claim 36, wherein the seal forming structure and the undercushion are formed from one homogeneous piece of material.

38. The patient interface of claim 36 or 37, wherein the seal forming structure and the undercushion are formed from silicone.

39. A seal-forming structure for a patient interface configured to provide sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to the patient’s airways including at least an entrance of a patient’s nares, wherein the t interface is configured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the patient’s respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing, the seal-forming structure comprising: an outer ne configured to form a seal with the inferior periphery of the patient’s nose, the outer membrane having an or portion to form a seal with the patient’s lip superior, and the outer membrane having two alar sealing portions, each alar sealing portion being shaped and dimensioned to seal between corresponding ones of the t’s nasal ala and nasolabial sulcus; at least one opening formed through the outer membrane to provide sealed delivery of the flow of air at the continuously positive pressure with respect to ambient air pressure to one or both of the patient’s nares; an undercushion layer to support the inferior n against the patient’s lip superior and having alar sealing portion supports that correspond to each of the alar sealing portions to support the alar sealing portions between corresponding ones of the t’s nasal ala and nasolabial sulcus; ResMed Ref: P1218NZ3 a superior portion to form a seal proximal to the tip of the patient’s nose, the superior n not being supported by the undercushion layer; and a lateral n on each lateral side of the seal-forming structure to form a seal with a corresponding ala of the patient’s nose, wherein the outer membrane comprises a thickened region at each lateral portion that is thicker than the remainder of the outer membrane.

40. The seal-forming structure of claim 39, wherein the undercushion layer extends partially around the periphery of the outer membrane.

41. The seal-forming structure of claim 39 or 40, wherein the undercushion layer terminates at each lateral side at the alar sealing portion supports.

42. The seal-forming structure of any one of claims 39 to 41, wherein in use the orming structure does not extend beyond the patient’s septal cartilage.

43. The orming ure of any one of claims 39 to 41, wherein in use the seal-forming structure does not extend beyond the patient’s alar cartilage.

44. The seal-forming structure of any one of claims 39 to 43, further comprising one opening formed through the outer membrane to provide sealed delivery of the flow of air at the continuously positive pressure with respect to ambient air pressure to both of the t’s nares.

45. The seal-forming structure of any one of claims 39 to 43, further comprising: two openings formed through the outer membrane to provide sealed delivery of the flow of air at the continuously positive pressure with respect to t air re to a corresponding one of the patient’s nares; and a columella engagement portion between the openings to engage the lla of the patient’s nose. ResMed Ref: P1218NZ3

46. A patient interface for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to the patient’s airways including at least an entrance of a patient’s nares, wherein the patient interface is configured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout the t’s respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered ing, said t interface comprising: a plenum chamber pressurised at a pressure above t pressure in use; the seal forming structure of any one of claims 39 to 45, the seal forming structure having a plenum chamber connection portion attached to the plenum chamber; and a oning and ising structure to maintain the seal forming structure in sealing contact with an area nding the entrance to the patient’s airways while maintaining a therapeutic pressure at the ce to the patient’s airways.

47. A patient interface comprising: a plenum chamber pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum chamber including a plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by a patient, a seal-forming structure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways, the seal-forming structure constructed and arranged to maintain said eutic pressure in the plenum chamber throughout the patient’s respiratory cycle in use; a positioning and stabilising structure to provide a force to hold the seal-forming structure in a eutically ive position on the patient’s head, the positioning and stabilising structure comprising a tie, the tie being constructed and arranged so that at least a portion overlies a region of the t’s head superior to an otobasion superior of the patient’s head in use; and ResMed Ref: P1218NZ3 a vent structure to allow a continuous flow of gases exhaled by the patient from an interior of the plenum chamber to ambient, said vent ure being sized and shaped to maintain the therapeutic pressure in the plenum chamber in use, wherein the patient interface is configured to allow the patient to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient interface is configured to leave the patient’s mouth uncovered, wherein the orming structure further comprises a patient-contacting surface configured to engage the patient’s facial skin at the underside of the t’s nose to form a seal and a posterior opening formed in the patient-contacting surface, the posterior opening configured to provide the flow of air at said therapeutic pressure to the patient’s nares, and wherein the seal-forming ure includes a support structure extending from the patient contacting surface to an interior surface of the seal-forming structure, the support structure and the interior surface forming a continuous loop.

48. The patient ace of claim 47, wherein the seal-forming structure further comprises an anterior opening formed in a non-patient contacting surface and an anterior tie that spans the anterior opening, and wherein a first end of the support structure is connected to the anterior tie.

49. The patient interface of claim 48, wherein the seal-forming structure further ses an edge bounding the posterior g in the patient ting surface, and wherein a second end of the t ure is connected to the patient contacting surface at a superior region of the edge.

50. The patient interface of any one of claims 47 to 49, wherein the rming structure further comprises an undercushion that supports the patient contacting surface. ResMed Ref: P1218NZ3

51. The patient interface of claim 50, wherein an inferior portion of the sealforming structure includes the undercushion and a or portion of the sealforming structure does not include the undercushion.

52. The patient interface of claim 50, wherein the undercushion is structured to only support the t contacting surface against the patient’s lip superior.

53. A seal-forming structure for a patient interface, the seal-forming ure constructed and arranged to form a seal with a region of the patient’s face surrounding an entrance to the patient’s airways, the seal-forming ure constructed and arranged to maintain a therapeutic pressure of at least 6 cmH2O above ambient air pressure in a plenum chamber throughout the t’s respiratory cycle in use, the seal-forming structure sing: a patient-contacting e configured to engage the patient’s facial skin at the underside of the patient’s nose to form a seal; a posterior opening formed in the t-contacting surface, the posterior opening configured to provide the flow of air at said therapeutic pressure to the patient’s nares; and a support structure extending from the patient ting surface to an interior surface of the orming structure, the support structure and the interior surface forming a continuous loop, wherein the patient interface is configured to allow the patient to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient interface is configured to leave the patient’s mouth uncovered.

54. The seal-forming structure of claim 53, further comprising an anterior opening formed in a non-patient contacting surface and an anterior tie that spans the anterior opening, and wherein a first end of the support structure is connected to the anterior tie. ResMed Ref: P1218NZ3

55. The seal-forming structure of claim 54, further comprising an edge bounding the posterior opening in the patient contacting surface, and wherein a second end of the support ure is connected to the patient contacting surface at a superior region of the edge.

56. The seal-forming structure of any one of claims 53 to 55, further comprising an undercushion that supports the t contacting e.

57. The seal-forming structure of claim 56, wherein an inferior portion of the seal-forming structure includes the undercushion and a or portion of the sealforming structure does not include the undercushion.

58. The seal-forming ure of claim 57, wherein the undercushion is structured to only support the patient contacting surface against the patient’s lip superior. ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3 ResMed Ref: Z3