[0001] This application claims the benefit of priority from United States Provisional Patent Application No. 63/369,827, filed July 29, 2022, the entire content of which is incorporated herein by reference.

BACKGROUND

Field

[0002] The present disclosure relates to headgear for use in respiratory support. More particularly, though not exclusively, the disclosure relates to a chin restraint.

Description of Related Art

[0003] A respiratory support system delivers a flow of gases to a patient through a patient interface during the provision of respiratory support. Various types of patient interfaces may be used, such as a nasal cannula, nasal mask, full-face mask, or other types of patient interfaces.

[0004] Some forms of respiratory support, such as non-invasive ventilation (NIV) and positive airway pressure (PAP) therapy, including for example continuous positive airway pressure (CPAP), bi-level positive airway pressure (bi-level PAP or BPAP) and automatic positive airway pressure (APAP) therapy, involve the delivery of pressurized gases to the airways of a patient at a desired pressure level above ambient pressure. To ensure gases are delivered at the desired pressure level, the respiratory support system may be a sealed system which has no significant unintentional leaks.

[0005] Mouth leak can occur if respiratory therapy is delivered to the patient's nasal cavity with a nasal patient interface but the mouth of the patient is open or opens during delivery of the therapy. The patient's open mouth may provide a pathway for the pressurized gases to bypass the patient's lungs. The presence of a mouth leak may effectively render the respiratory support system unsealed due to gases being able to leave the patient's mouth to atmosphere. This can unintentionally reduce the pressure of gases in the respiratory support system below a desired pressure level. The sub-optimal pressure level may compromise the efficacy of the respiratory support.

[0006] Headgear, such as a chin restraint, may be fitted to a patient and can be used to urge the mouth of the patient closed to reduce mouth leak and ensure that gases are delivered at to the patient at the desired pressure level. But chin restraints may be uncomfortable for the patient, inconvenient to don, and/or inconvenient to adjust, for example. BRIEF SUMMARY

[0007] In a first aspect, a headgear for use in respiratory support comprises: a chin portion configured to engage a chin of a patient, in use; an upper portion configured to engage at least part of at least one of a frontal bone and a parietal bone of a head of the patient, in use; a first side portion and a second side portion configured to engage respective sides of the head of the patient, in use, wherein each of the first side portion and the second side portion is coupled or configured to be coupled to the chin portion and the upper portion, and wherein the chin portion, the upper portion, the first side portion and the second side portion are arranged to form a loop; and an adjustment strap comprising a first end coupled to the chin portion or the upper portion, and a second end configured to be adjustably coupled to the loop; wherein the first side portion has a greater degree of stretch, in a circumferential direction of the loop, than each of the chin portion, the upper portion and the adjustment strap; and wherein the second end of the adjustment strap is configured to be adjustably coupled to the loop to selectively limit the degree of stretch of the first side portion, in the circumferential direction, in use.

[0008] The degree of stretch of the first side portion in the circumferential direction may be such that a ratio of maximum extended length to resting length of the first side portion is between about 1.5: 1 and 2: 1.

[0009] The second end of the adjustment strap may be configured to be adjustably coupled to the loop to selectively limit the degree of stretch of the first side portion in the circumferential direction such that an effective ratio of maximum extended length to resting length of the first side portion is between about 1 : 1 and 1.1 : 1.

[0010] The degree of stretch of the chin portion in the circumferential direction may be such that a ratio of maximum extended length to resting length of the chin portion is between about 1: 1 and 1.1: 1.

[0011] The degree of stretch of the upper portion in the circumferential direction may be such that a ratio of maximum extended length to resting length of the upper portion is between about 1 : 1 and 1.1 : 1. [0012] The degree of stretch of the adjustment strap in the circumferential direction is such that a ratio of maximum extended length to resting length of the adjustment strap is between about 1 : 1 and 1.1 : 1.

[0013] The degree of stretch of two or more of the chin portion, the upper portion and the adjustment strap, in the circumferential direction, may be within about 5% of each other.

[0014] The chin portion and the adjustment strap may be formed from the same material.

[0015] The chin portion and the upper portion may be formed from the same material.

[0016] The first end of the adjustment strap may be coupled to one of the chin portion or the upper portion, wherein the adjustment strap is configured to extend over the first side portion in the circumferential direction, and the second end of the adjustment strap is configured to adjustably couple to the other of the chin portion or the upper portion.

[0017] The first end of the adjustment strap and the chin portion may be permanently coupled to each other.

[0018] The first end of the adjustment strap may be integrally formed with the chin portion.

[0019] The first end of the adjustment strap and the chin portion may be configured to be removably coupled to each other.

[0020] The first end of the adjustment strap may be configured to be removably coupled at or adjacent a junction between the first side portion and the chin portion.

[0021] The adjustment strap may be configured to extend over the first side portion so that the second end of the adjustment strap is configured to be adjustably coupled to the upper portion, in use.

[0022] The first end of the adjustment strap may extend from a junction between the first side portion and the chin portion.

[0023] The first end of the adjustment strap and the upper portion may be permanently coupled. [0024] The first end of the adjustment strap may be configured to be removably coupled to the upper portion.

[0025] The adjustment strap may be configured to extend over the first side portion so that the second end of the adjustment strap is configured to be adjustably coupled to the chin portion, in use.

[0026] The chin portion, the upper portion, the first side portion and the second side portion may be respectively permanently coupled or integrally formed to form the loop permanently.

[0027] Each of the first side portion and the second side portion may be directly connected to the upper portion and the chin portion to form the loop.

[0028] Any one or more pairs of the chin portion and the first side portion, the first side portion and the upper portion, the upper portion and the second side portion, and the second side portion and the chin portion may be configured to be removably coupled with each other to form the loop.

[0029] The chin portion, the upper portion and the adjustment strap may be substantially inextensible.

[0030] One or more of the upper portion, the chin portion, the first side portion, the second side portion and the adjustment strap may have anisotropic stretch.

[0031] At least one of the chin portion and the upper portion may comprise one or more regions of tacky material on a patient-contacting surface.

[0032] The tacky material may comprise any one or more of: a tape comprising a polyurethane adhesive film and a polyurethane elastic barrier, neoprene, silicone, thermoplastic polyurethane, polyester, or co-polyolefin, co-polyamide, and ethylene vinyl acetate co-polymer thermoplastic.

[0033] The tacky material may be heat-pressed onto the patient-contacting surface of at least one of the chin portion and the upper portion.

[0034] The one or more regions of tacky material may inhibit the degree of stretch of at least one of the chin portion and the upper portion. [0035] The one or more regions of tacky material may be located at or adjacent at least one of a junction between the first side portion and the chin portion and a junction between the first side portion and the upper portion.

[0036] The second end of the adjustment strap may comprise a fastener.

[0037] The adjustment strap may comprise one of a hook material or a loop material and the loop may comprise the other of the hook material or the loop material, wherein the hook material and the loop material are configured to attach to each other to adjustably couple the second end of the adjustment strap to the loop.

[0038] The adjustment strap may comprise a hook material and an outer-facing surface of the upper portion may comprise a loop material.

[0039] The loop material may be an unbroken loop (UBL) fabric.

[0040] A width of the first side portion may be greater than a width of the adjustment strap.

[0041] The chin portion may be coupled to at least one of the first side portion and the second side portion by one or more of stitching, adhesive and welding.

[0042] The upper portion is connected to at least one of the first side portion and the second side portion by one or more of stitching, adhesive and welding.

[0043] An edge of the first side portion which couples to the upper portion may be formed with a convex profile.

[0044] An edge of the upper portion which joins to the first side portion has a convex profile.

[0045] The chin portion may comprise a slit.

[0046] The chin portion comprises a chin cup.

[0047] The first side portion may have a width in a region adjacent the upper portion which is greater than the width of the first side portion in a region adjacent the chin portion.

[0048] The width of the first side portion may taper from the region adjacent the upper portion to the region adjacent the chin portion.

[0049] Each of the first side portion and the second side portion may be configured to at least partially cover a respective ear of the patient, in use. [0050] At least one of the first side portion and the second side portion may be formed from a material comprising at least one of spandex, cotton and nylon.

[0051] At least one of the chin portion, the upper portion and the adjustment strap may be formed from a material comprising at least one of spandex, cotton and nylon.

[0052] The second side portion may have a greater degree of stretch, in the circumferential direction, than each of the chin portion, the upper portion and the adjustment strap.

[0053] The degree of stretch of the second side portion in the circumferential direction may be such that a ratio of maximum extended length to resting length of the second side portion is between about 1.5: 1 and 2: 1.

[0054] The first side portion and the second side portion may have substantially the same degree of stretch in the circumferential direction.

[0055] The first side portion and the second side portion may be formed from the same material.

[0056] The headgear may comprise a second adjustment strap, the second adjustment strap comprising a first end coupled to one of the chin portion or the upper portion, and a second end configured to be adjustably coupled to the loop.

[0057] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0058] In a second aspect, there is provided a headgear for use in respiratory support, the headgear comprising : a chin portion configured to engage a chin of a patient, in use; an upper portion configured to engage at least part of at least one of a frontal bone and a parietal bone of a head of the patient, in use; and a first side portion and a second side portion configured to engage respective sides of the head of the patient, in use, wherein each of the first side portion and the second side portion is coupled or configured to be coupled to the chin portion and the upper portion, and wherein the chin portion, the upper portion, the first side portion and the second side portions are permanently coupled or integrally formed as a loop; wherein the first side portion has a greater degree of stretch than each of the chin portion and the upper portion, in a circumferential direction of the loop. [0059] A degree of stretch of the first side portion in the circumferential direction may be such that a ratio of maximum extended length to resting length of the first side portion is between about 1.5: 1 and 2: 1.

[0060] The degree of stretch of the chin portion in the circumferential direction may be such that the ratio of maximum extended length to resting length of the chin portion is between about 1 : 1 and 1.1 : 1.

[0061] The degree of stretch of the upper portion in the circumferential direction may be such that the ratio of maximum extended length to resting length of the upper portion is between about 1 : 1 and 1.1 : 1.

[0062] The headgear may comprise an adjustment strap, the adjustment strap comprising: a first end coupled or configured to be coupled to the chin portion or the upper portion, and a second end configured to be adjustably coupled to the other of the chin portion or the upper portion.

[0063] The first end of the adjustment strap may be permanently coupled to the chin portion.

[0064] The first end of the adjustment strap may be configured to be removably coupled to the chin portion.

[0065] The first end of the adjustment strap may be permanently coupled to the upper portion.

[0066] The first end of the adjustment strap may be configured to be removably coupled to the upper portion.

[0067] The first side portion may have a greater degree of stretch than the adjustment strap in the circumferential direction.

[0068] The degree of stretch of the adjustment strap in the circumferential direction may be such that the ratio of maximum extended length to resting length of the adjustment strap is between about 1 : 1 and 1.1 : 1.

[0069] The second end of the adjustment strap may be configured to be adjustably coupled with the other of the chin portion and the upper portion to selectively limit a degree of stretch of the first side portion in the circumferential direction such that an effective ratio of maximum extended length to resting length of the first side portion is between about 1 : 1 and 1.1: 1.

[0070] The chin portion and the adjustment strap may be formed from the same material.

[0071] The adjustment strap may have anisotropic stretch.

[0072] The second side portion may have a greater degree of stretch than the adjustment strap, in the circumferential direction.

[0073] The headgear may comprise a second adjustment strap, the second adjustment strap comprising : a first end coupled or configured to be coupled to the chin portion or the upper portion, and a second end configured to be adjustably coupled to the other of the chin portion and the upper portion.

[0074] The second end of the adjustment strap may be configured to be adjustably coupled to the loop to selectively limit a degree of stretch of the first side portion, and/or the second end of the second adjustment strap may be configured to be adjustably coupled to the loop to selectively limit a degree of stretch of the second side portion.

[0075] The chin portion and the upper portion may be formed from the same material.

[0076] At least one of the upper portion and the chin portion may have anisotropic stretch.

[0077] The second side portion may have a greater degree of stretch than each of the chin portion and the upper portion, in the circumferential direction.

[0078] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0079] The second side portion of the headgear of each of the first and second aspects may be a mirror-image of the first side portion.

[0080] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims. [0081] In a third aspect, there is provided a headgear for use in respiratory support, the headgear comprising : a resiliently-extensible loop configured to fit about a head of a patient, and an adjustment strap configured to be adjustably attached to the resilient loop in parallel therewith to selectively limit extensibility of at least a portion of the resilient loop.

[0082] The headgear may be in the form of a chin restraint configured to restrain movement of a mandible of the patient, in use.

[0083] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0084] The headgear of each of the first to third aspects may be symmetric about a sagittal plane.

[0085] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0086] In a fourth aspect, a headgear for use in respiratory support comprises: a chin portion configured to engage a chin of a patient, in use; an upper portion configured to engage at least part of at least one of a frontal bone and a parietal bone of a head of the patient, in use; a first side portion and a second side portion configured to engage respective sides of the head of the patient, in use, wherein each of the first side portion and the second side portion is coupled or configured to be coupled to the chin portion and the upper portion, and wherein the chin portion, the upper portion, the first side portion and the second side portion are arranged to form a loop; and an adjustment strap comprising a first end coupled to the chin portion or the upper portion, and a second end configured to be adjustably coupled to the loop; wherein the first side portion has a greater degree of stretch, in a circumferential direction of the loop, than one or more of the chin portion, the upper portion and the adjustment strap; and wherein the second end of the adjustment strap is configured to be adjustably coupled to the loop to selectively limit the degree of stretch of the first side portion, in the circumferential direction, in use.

[0087] The degree of stretch of the first side portion may be greater than that of at least the adjustment strap.

[0088] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0089] In a fifth aspect, there is provided a headgear for use in respiratory support, the headgear comprising : a chin portion configured to engage a chin of a patient, in use; an upper portion configured to engage at least part of at least one of a frontal bone and a parietal bone of a head of the patient, in use; and a first side portion and a second side portion configured to engage respective sides of the head of the patient, in use, wherein each of the first side portion and the second side portion is coupled or configured to be coupled to the chin portion and the upper portion, and wherein the chin portion, the upper portion, the first side portion and the second side portions are permanently coupled or integrally formed as a loop; wherein the first side portion has a greater degree of stretch than at least one of the chin portion and the upper portion, in a circumferential direction of the loop.

[0090] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0091] In a sixth aspect, there is provided a headgear for use in respiratory support, the headgear comprising : a loop configured to conform about a patient's head, in use, the loop comprising: a chin portion configured to engage the patient's chin, in use; an upper portion configured to engage at least part of at least one of a frontal bone and a parietal bone of a head of the patient, in use; a first side portion configured to engage a first side of the patient's head, in use; and a second side portion configured to engage a second side of the patient's head, in use; a first adjustment strap comprising : a first end permanently coupled with the loop; and a second end configured to be adjustably coupled with the loop; and a second adjustment strap comprising: a first end permanently coupled with the loop; and a second end configured to be adjustably coupled with the loop.

[0092] The first end of the first adjustment strap may be permanently coupled with the loop at a junction between the first side portion and the chin portion, and the first end of the second adjustment strap may be permanently coupled with the loop at a junction between the second side portion and the chin portion.

[0093] The first ends of the first adjustment strap and the second adjustment strap may be integrally formed with the chin portion.

[0094] The second ends of the first adjustment strap and the second adjustment strap may each comprise a fastener configured to adjustably couple with the upper portion.

[0095] In a seventh aspect, there is provided a headgear for use in respiratory support, the headgear comprising a resilient loop configured to conform about a patient's head and engage the patient's chin to urge the patient's mouth closed, in use, the loop comprising a patient-contacting surface and an outer-facing surface, the patient-contacting surface comprising one or more friction members configured to frictiona lly engage the patient's head and inhibit movement of at least a portion of the resilient loop with respect to the patient's head, in use.

[0096] The headgear may further comprise one or more adjustment straps configured to permit adjustment of tension in one or more portions of the resilient loop.

[0097] A degree of stretch of the one or more adjustment straps may be less than a degree of stretch of at least a portion of the resilient loop.

[0098] The one or more friction members may comprise a tacky material. [0099] The one or more friction members may comprise a plurality of friction members arranged in a pattern. The pattern may comprise a striped pattern or a polka dot pattern.

[0100] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0101] In an eighth aspect, there is provided a patient interface assembly for delivering respiratory support to a patient, the patient interface assembly comprising: a patient interface configured to deliver a flow of gases to the patient; and a headgear according to any of the first to seventh aspects.

[0102] The patient interface may be a sealing interface.

[0103] The sealing interface may be a nasal mask or a nasal cannula.

[0104] In some examples, the patient interface may not be attachable to the headgear.

[0105] The patient interface assembly may comprise an additional headgear to secure the patient interface to the patient.

[0106] The additional headgear may be one of a bonnet, a beanie, a cap, or a strap assembly.

[0107] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0108] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0109] In a ninth aspect, there is provided a kit for a respiratory support system, the kit comprising : a patient interface configured to deliver a flow of gases to a patient; and a headgear according to any one of the first to seventh aspects.

[0110] The kit may comprise a pressure regulator such as a bubbler.

[0111] The patient interface may comprise a sealing interface. [0112] The sealing interface may be a nasal mask or a nasal cannula.

[0113] The kit may comprise at least one inspiratory conduit.

[0114] The kit may comprise at least one expiratory conduit.

[0115] The kit may comprise an additional headgear configured to secure the patient interface in position on the patient.

[0116] The additional headgear may be one of: a bonnet, a beanie, a cap, or a strap assembly.

[0117] Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

[0118] Further aspects, novel features and advantages of the present disclosure will be readily apparent to those skilled in the art in light any one or more of the illustrative examples set out in the detailed description and drawings. The description and drawings are to be regarded as illustrative in nature, and not restrictive. Modifications or improvements may be made without departing from the spirit or scope of the disclosure and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0119] A number of examples are described below by way of non-limiting example and with reference to the accompanying drawings.

[0120] FIG. 1 illustrates an example of a respiratory support system in which examples of headgear according to the present disclosure may be used.

[0121] FIG. 2 illustrates another example respiratory support system in which examples of headgear according to the present disclosure may be used.

[0122] FIG. 3 illustrates an example of a headgear according to the present disclosure, when doffed.

[0123] FIG. 4 illustrates a side view of the headgear of FIG. 3 in use, i.e., donned by a patient.

[0124] FIG. 5 illustrates a top view of the headgear of FIG. 3 and FIG. 4, in use.

[0125] FIG. 6 illustrates a front view of the headgear of FIG. 3 to FIG. 5, in use. [0126] FIG. 7 illustrates a bottom perspective view of the headgear of FIG. 3 to FIG.

6, in use.

[0127] FIG. 8 illustrates a detailed view of the loop formed by a chin portion, side portions, and upper portion of the headgear of FIG. 3 to FIG. 7, when doffed.

[0128] FIG. 9 illustrates an alternative detailed view of the loop of the headgear of FIG. 3 to FIG. 8, when doffed.

DETAILED DESCRIPTION

[0129] Unless the context clearly requires otherwise, throughout the description and claims the words "comprising," "including" and variants are to be construed in the inclusive sense, rather than the exhaustive sense. That is, the terms should be construed in the sense of "including, but not limited to" rather than "consisting solely of."

[0130] FIG. 1 shows an example respiratory support system 100 for treating a patient 102, in which various examples of headgear according to the present disclosure may be used. The respiratory support system 100 may broadly comprise one or more of a gases source 104, a humidifier supply conduit 106, a humidifier 108, an inspiratory conduit 110, a patient interface 112, a headgear 114, an expiratory conduit 116, a bubbler 118 and a stand 120.

[0131] In the illustrated example, a humidified Positive End Expiratory Pressure (PEEP) system is shown. A patient 102 may receive an inspiratory flow of gases from the gases source 104 via the inspiratory conduit 110 and the patient interface 112. The patient interface 112 may be secured in place on the patient by the headgear 114. The humidifier supply conduit 106 and humidifier 108 may optionally be provided to humidify the inspiratory flow of gases. A flow of expiratory gases may be directed from the patient interface 112 to ambient air via an expiratory conduit 116 and a pressure regulator, which in the illustrated arrangement comprises the bubbler 118.

[0132] In use, the gases source 104 may receive the inspiratory flow of gases from a wall source of compressed air, oxygen or other breathing gases. As an example, control of the inspiratory flow of gases may be achieved with an electronically- controlled proportional solenoid valve (PSV). In other examples, the gases source 104 may receive the inspiratory flow of gases from a compressed gas cylinder (not shown), or the gases source 104 may be configured to pressurize ambient gases, e.g., with a blower. [0133] The inspiratory flow of gases is fed from the gases source 104 to the humidifier 108 by the humidifier supply conduit 106.

[0134] In some examples, the humidifier 108 may include a chamber sitting atop a heater base. The chamber may be configured to contain a supply of water or other liquids suitable for humidifying the inspiratory flow of gases. The chamber may be removably and replaceably mounted to the heater base, e.g., for refilling with water, cleaning or replacement. The heater base may heat the water contained within the chamber. Water vapor within the chamber may be picked up by the inspiratory flow of gases as it passes through the headspace of the chamber, thereby raising the humidity of the inspiratory flow of gases.

[0135] The humidified inspiratory flow of gases is delivered from the humidifier 108 to the airway of the patient 102 by the inspiratory conduit 110 and the patient interface 112. In some examples, the respiratory support system 100 may include further inspiratory conduits. For example, in addition to the inspiratory conduit 110, the respiratory support system 100 may have another inspiratory conduit between inspiratory conduit 110 and the patient interface 112. The additional inspiratory conduit may be connectable to, or integrated with, the patient interface 112, for example.

[0136] Excess and expired gases may be evacuated from the patient interface 112 by the expiratory conduit 116. The respiratory support system 100 may include further expiratory conduits for transporting the expiratory flow of gases away from the patient 102. For example, in addition to the expiratory conduit 110, the respiratory support system 100 may have another expiratory conduit between the patient interface 112 and the expiratory conduit 116. The additional expiratory conduit may be connectable to, or integrated with, patient interface 112, for example. In some examples, excess and expired gases may be evacuated from the patient interface 112 via one or more vents to atmosphere. The vents may be provided in the patient interface 112 or in a coupling, for example.

[0137] In the example shown, the pressure regulator may be a bubbler 118. The bubbler 118 may be configured to contain a reservoir of water or other liquid, and may comprise an adjustable inlet and an outlet. The adjustable inlet may comprise an inlet tube. The adjustable inlet may comprise an end positioned within the bubbler 118. The end may be configured to be adjustably immersed within the reservoir of water, in use. Other forms of pressure regulator may be used. The pressure regulator may provide resistance to the expiratory flow of gases exiting the respiratory support system 100, e.g., to ambient air. This resistance may provide a desired peak end expiratory pressure (PEEP). The PEEP may be adjustable. For example, in the case of the bubbler 118, the PEEP may be adjusted by adjusting the depth of the inlet tube immersed within the reservoir of water contained within the bubbler 118. In use, the expiratory flow of gases may exit the inlet and bubble up through the reservoir of water. This bubbling may result in small oscillations in the pressure of the gases within the respiratory support system 100. The oscillations may be clinically beneficial to the patient. Respiratory therapy delivered by the respiratory support system 100 may be referred to as Bubble CPAP.

[0138] In some examples, as illustrated, the gases source 104, the humidifier 108, and the bubbler 118 may be mounted on a stand 120 which can be positioned near the patient 102. The stand may comprise wheels. The wheels may aid relocation of the respiratory support system 100.

[0139] In some examples, the patient interface 112 may be a sealing interface which contacts the face of the patient 102 to create a seal around an airway of the patient 102. In some examples, the patient interface 112 may seal around, against, and/or within the patient's nares. In some examples, the patient interface 112 may be a sealing nasal cannula. In other examples, the patient interface 112 may comprise a mask, e.g., a nasal mask.

[0140] In other examples, at least one of the pressure regulator (e.g., bubbler 118) and the humidifier 108 may be integrated with the gases source 104. Although a water-based pressure regulator, bubbler 118, is shown in FIG. 1 for administering "bubble CPAP" therapy as the respiratory support, it is to be appreciated that the pressure regulator may be any other mechanical or electrical pressure regulator.

[0141] FIG. 2 shows another example respiratory support system 200 in which headgear according to the present disclosure may be used. In the illustrated arrangement, a humidified Positive End Expiratory Pressure (PEEP) system is shown. The patient 102 may receive an inspiratory flow of gases from a gases source 104 via an inspiratory conduit 110 and a patient interface 112. The gases source 104 of the respiratory support system 200 comprises a blower (e.g., a centrifugal fan driven by a variable-speed electric motor).

[0142] The respiratory support system 200 may comprise an optional humidifier 108. The flow of gases from gases source 104 is provided by the humidifier supply conduit 106 to an inlet of the humidifier 108. The inspiratory conduit 110 is connected to an outlet of the humidifier 108 to convey the humidified inspiratory flow of gases to the patient interface 112. The patient interface 112 may be secured on the patient 102 by the headgear 114. The patient interface 112 in this example may comprise a nasal mask. Or the patient interface 112 may comprise any other suitable patient interface. [0143] The inspiratory conduit 110 may contain a heater wire 202 or other heat source. The heater wire 202 may be configured to maintain, or in some cases raise, the temperature of the inspiratory flow of gases to mitigate condensation within the inspiratory conduit 110. The heater wire 202 may be provided within the lumen of the inspiratory conduit 110, embedded in the tube wall of the inspiratory conduit 110, or wrapped around the tube wall. In some examples, the inspiratory conduit 110 may comprise two or more heating zones, e.g., an upstream heating zone and a downstream heating zone. Two or more heating zones may be advantageous for a neonatal patient within an incubator, for example.

[0144] In the example shown, the expiratory flow of gases are conveyed by the expiratory conduit 116 to a pressure regulator, which in the illustrated arrangement is a bubbler 118.

[0145] In some examples, the gases source 104 and at least part of the humidifier 108 may be integrated, e.g., within a common housing. The integrated device may comprise a removable and replaceable chamber.

[0146] The respiratory support provided to the patient 102 by respiratory support systems 100, 200 involves the delivery of PEEP gases and may be CPAP therapy, NIV, or another form of positive airway pressure (PAP) therapy. It is to be understood, however, that the present disclosure is not limited to use with respiratory support systems delivering PEEP gases, and may be used with other types of respiratory support systems which may not necessarily involve humidification.

[0147] An example headgear 300 according to an example of the present disclosure is illustrated in FIG. 3 to FIG. 9. The example headgear 300 is in the form of a chin restraint configured to restrain movement of a patient's mandible, in use.

[0148] Referring first to FIG. 3, the headgear 300 is shown in a doffed state, i.e., not in use. In some examples the headgear 300 may comprise one or more, and preferably all, of an upper portion 302, a chin portion 304, a first side portion 306, a second side portion 308, a first adjustment strap 310 and a second adjustment strap 312.

[0149] The headgear 300 may be used in the respiratory support system 100 or respiratory support system 200, for example. The headgear 300 may urge the mouth of the patient 102 closed to reduce mouth leak. Mouth leak refers to inspiratory or expiratory gases which leave the patient through the mouth to ambient air. Mouth leak can unintentionally reduce the pressure of the gases in the respiratory support system which can compromise the efficacy and/or safety of the delivered respiratory support. [0150] For example, the provision of bubble CPAP therapy typically involves a sealed respiratory support system having no significant unintentional leaks in order to maintain a reliable delivered pressure. Mouth leak is an indication the respiratory support system is no longer sealed, which may impact the reliability of the delivered pressure to the patient by unintentionally reducing this delivered pressure. The headgear 300 can be donned by the patient 102 and may reduce mouth leak to ensure that desired pressure levels are delivered to patient 102 during the provision of respiratory support, such as CPAP therapy.

[0151] Mouth leak can impact the delivered pressure levels during respiratory support if the patient interface 112 seals only with, or around, the nares of the patient, such as if the patient interface 112 is a nasal mask or a nasal cannula. If the mouth of a patient is not urged closed then mouth leak will introduce a leak to the respiratory support system, despite an effective seal between the nasal mask or nasal cannula and the patient's nasal passages. The mouth leak can reduce the pressure of the gases delivered to the patient's lungs.

[0152] Movement of the patient's mouth can cause leaks and impact pressure levels during respiratory support even if the patient interface 112 is configured to seal with both the mouth and nose of the patient, such as if the patient interface 112 a full-face mask. And movement of the mouth may contribute to, or irritate, pressure sores resulting from use of the patient interface, e.g., at the nasal bridge region.

[0153] Headgear in accordance with the present disclosure may be used as, or in combination with, headgear 114 in respiratory support system 100 or respiratory support system 200, for example. The headgear 300 may improve patient comfort and/or efficacy of therapy during provision of respiratory support. More particularly, the example headgear 300 is configured to be used in combination with additional headgear 114 configured to secure a patient interface in position on the patient's head. The additional headgear may be one or more of a bonnet, a beanie, a cap or a strap assembly, for example. In other examples, headgear in accordance with the present disclosure may be adapted to both urge the patient's mouth closed and secure the patient interface in place on the patient's head. For example, the headgear may include further interface-securing straps configured to secure a nasal cannula or nasal mask in position to seal with, or around, the patient's nares.

[0154] The headgear 300 may be constructed, at least in part, from a material which provides thermal insulation to the patient's head when donned. Thermal insulation may be particularly beneficial if the patient is an infant. Infant patients may be unable regulate their own body temperature. [0155] "Donned" refers to the state of the headgear 300 when it is being worn by the patient, whether applied by the patient themselves or another person (e.g., a clinician). "Doffed" refers to the state of the headgear when it is not being worn by the patient. The headgear 300 is shown doffed in FIG. 3 and donned in FIG. 4, for example.

[0156] When donned, the headgear 300 may physically protect the patient's head. For example, the headgear 300 may protect the patient's head from abrasion, e.g., caused by contact with one or more of the additional headgear 114, inspiratory conduit 110 and/or the expiratory conduit 116 of the respiratory support system 100 or respiratory support system 200. This protection may be particularly beneficial if the patient is an infant. Infant patients may have delicate skin susceptible to skin damage.

[0157] The upper portion 302 of the headgear 300 may be configured to engage an upper and/or upper rear portion of the patient's head. In some examples, the upper portion 302 may be configured to engage at least part of one of the frontal and/or parietal bones of the patient's skull. Additionally, or alternatively, in some examples the upper portion 302 may be configured to engage at least part of the occipital bone of the patient's skull. The upper portion 302 may cover a part of the patient's head. And the upper portion 302 may protect this part of the patient's head from contact with various components of the respiratory support system, such as the inspiratory conduit 110 and/or the expiratory conduit 116.

[0158] The chin portion 304 may be configured to engage the patient's mandible. As best shown in FIG. 7, the chin portion 304 may be configured to engage the patient's mental protuberance (i.e., chin), in use.

[0159] The first side portion 306 and the second side portion 308 may be configured to engage respective sides of the patient's head when the headgear 300 is donned, in use. For example, the side portions 306, 308 may each engage the patient's head to overlie at least part of the respective mandible, temporal and parietal bones, and/or the risorius, masseter, auricularis anterior, auricularis superior, and temporalis muscles.

[0160] The upper portion 302 and the chin portion 304 may be joined by the first side portion 306 and the second side portion 308 on opposing sides of the headgear 300. The upper portion 302, chin portion 304, first side portion 306 and second side portion 308 may form a resiliently-extensible loop 314. The loop arrangement of the headgear 300 may facilitate fitting of the headgear 300 to the patient 102. In particular, the loop 314 may aid in orientation of the headgear 300. One or more portions of the headgear 300 may be configured to intuitively align with the parts of a patient's head which they are respectively configured to engage. For example, the chin portion 304 may be sized and shaped so that it is apparent to users that it is intended to engage the chin. For example, the chin portion may comprise a chin cup as described in further detail below. This orientation and alignment may save time during application of headgear 300 to the patient. This may be beneficial in the situation where respiratory support needs to be delivered to a patient urgently, e.g., in the case of an emergency. The headgear 300 may be be quickly or conveniently applied to reduce mouth leak during the provision of this respiratory support. Furthermore, the orientation and alignment of headgear 300 as described may aid in patient comfort and compliance in using headgear 300.

[0161] In some examples, one or more of the first side portion 306 and the second side portion 308 may be permanently coupled or integrally formed with one or more of the chin portion 304 and the upper portion 302 to form the loop 314. In one example, each of the first side portion 306 and second side portion 308 may be permanently coupled or integrally formed with both the chin portion 304 and the upper portion 302. Permanently coupled refers to a permanent connection which may be formed by welding, heat pressing, stitching, adhesive, or other suitable types of permanent coupling at a junction between respective portions of the headgear 300. Integrally formed refers to the respective portions being constructed or formed as one continuous piece of material, without the need for an additional step of attaching two (or more) separate portions to each other.

[0162] In some examples, the entire loop 314 can be integrally formed from one continuous piece of material and still have varying stretch properties between two or more of the chin portion 304, upper portion 302, and side portions 306, 308. For example, the loop 314 may be formed from a single length of material joined at its ends to have a single junction, or may be fully-fashioned to shape without any seams at all.

[0163] In some examples, the continuous piece of material can be modified in various locations in order to define chin portion 304, upper portion 302 and first and second side portions 306, 308 having stretch properties as discussed herein. In some examples, the continuous piece of material can be a knitted structure. As the knitted structure is being formed (e.g., by circular knitting, flat bed knitting, three- dimensional knitting, complete garment knitting, or WholeGarment® knitting), the type of knitting stitch, loop length, or the number of knitted loops in each course of the knitted structure may be varied, or non-knitted threads may be incorporated (e.g., "laid-in") to the knitted structure in selected areas in order to change the stretch properties and define the different portions of the headgear 300 as discussed herein. [0164] In some examples, the continuous piece of material may be formed and then one or more additional materials may be coupled to one or more locations of the continuous piece of material to define the portions of headgear 300 having various stretch properties as discussed herein. For example, a tacky material may be heat- pressed or glued at one or more locations along the continuous piece of material in a circumferential direction to reduce the degree of stretch in this direction relative to locations of the continuous piece of material which do not comprise this tacky material. The location with the relatively reduced degree of stretch may define the chin portion 304 or upper portion 302.

[0165] In yet other examples, the loop 314 may be formed from combinations of one or more continuous pieces of material and one or more portions coupled thereto.

[0166] In the illustrated example, the first side portion 306 and the second side portion 308 are each permanently coupled with the upper portion 302 and the chin portion 304 by stitching. In other examples, each of the first side portion 306 and the second side portion 308 may be indirectly connected, but still permanently coupled, with either or both of the upper portion 302 and the chin portion 304 by way of connection via intermediate sections of material.

[0167] In some examples, one or more of the junctions 316, 318, 320, 322 (see FIG. 8) between the chin portion 304, the upper portion 302, the first side portion 306 and the second side portion 308 may comprise a removable joint. The removable joint may comprise a hook-and-loop fastener, a releasable two-part adhesive connection, buckles, clips, or a protrusion (e.g., a dome) on one portion which is shaped to fit into one or more recesses (e.g., apertures) in another portion of the headgear, for example. In one example, the first upper junction 320 between the first side portion 306 and the upper portion 302 may comprise a removable hook-and-loop fastener (i.e., with complementary hook/loop portions permanently attached to each of the first side portion 306 and the upper portion 302 by stitching or welding, for example). The remaining junctions may comprise permanent stitched or welded joints.

In some examples, portions of the headgear may be removably coupled by a snap-fit, push-fit, or an interference-fit connection system.

[0168] The headgear 300 being permanently coupled or integrally formed as a loop 314 may advantageously reduce steps and/or save time in fitting the headgear 300 to the patient 102. A permanently coupled or integrally formed loop 314 may be more quickly and easily donned on a patient when compared to a headgear which is not integrally formed and where loop 314 may require adjustment of clips or buckles which can require additional time. A permanently coupled or integrally formed loop 314 may be especially beneficial for infant patients where a clinician applies the headgear 300 to the patient. A clinician may need to apply and remove a headgear many times to an infant patient during the provision of respiratory support in order to provide care or to clean the patient. A permanently coupled or integrally formed headgear may allow this quick and easy application and removal of the headgear multiple times. Additionally, further improving the quickness of applying headgear 300 to the patient is beneficial for the above-described urgency/emergency reasons.

[0169] In some examples, one of more of the first side portion 306 and second side portion 308 may be tapered, or configured to taper in use. As described in further detail below with reference to FIG. 9, the side portions 306, 308 may be wider at or adjacent the upper portion 302 than at or adjacent the chin portion 304, e.g., when donned.

[0170] One or more of the first adjustment strap 310 and the second adjustment strap 312 may have a first end 324 permanently coupled to, or integrally formed with, the loop 314, e.g., the chin portion 304. A second end 326 of one or more of the first adjustment strap 310 and second adjustment strap 312 may be configured to be adjustably coupled to the loop 314, e.g., the upper portion 302. In other examples, the second ends 326 of the first adjustment strap 310 and the second adjustment strap 312 may be configured to be adjustably coupled with each other. Either directly or via a buckle, for example.

[0171] In the example of FIG. 3 to FIG. 9, the first ends 324 of the adjustment straps 310, 312 are integrally formed with the chin portion 304 from one continuous length of material. And the second ends 326 are configured to be adjustably coupled to the upper portion 302.

[0172] In other examples, the first ends 324 of the adjustment straps 310, 312 may be permanently coupled to, or integrally formed with, the upper portion 302 and the second ends 326 may be configured to be adjustably coupled to the chin portion 304.

[0173] In some examples, the second ends 326 of the adjustment straps 310, 312 may alternatively, or additionally, be configured to be adjustably coupled to respective side portions 306, 308.

[0174] In some examples, the first ends 324 of the adjustment straps 308, 310 may also be removably and/or adjustably attached to the chin portion 304 or the upper portion 302.

[0175] Each of the second ends 326 of the adjustment straps 310, 312 may be in an attached configuration, in which the second ends 326 are coupled with the loop 314, with the adjustment strap arranged in parallel with the loop 314. Alternatively, they may each be in a non-attached configuration in which the second ends 326 are detached from the loop 314 (albeit potentially remaining indirectly attached to the loop 314 via the first ends 324, in at least some examples). For example, either or both of the second ends 326 may be in the non-attached configuration while the headgear 300 is being applied to the patient, or when the adjustment straps 310, 312 are being adjusted, and may be in the attached configuration following application and fitting of the headgear 300 to the patient.

[0176] The first side portion 306 and the second side portion 308 may each have substantially the same degree of stretch in the circumferential direction of loop 314. This may be the result of first side portion 306 and second side portion 308 being formed from the same material and in the same dimensions. In some examples, the first side portion 306 and the second side portion 308 may be a mirror-image of each other.

[0177] Both side portions 306, 308 having the same degree of stretch may be beneficial when applying headgear 300 to the patient. It may result in an easier and more consistent application due to both side portions having similar conformity when contacting the patient's head. This conformity may help with alignment of the upper portion 302 and the chin portion 304 on the patient's head. The similar stretch in each side portion may aid symmetrical adjustments when fitting.

[0178] A degree of stretch of a portion of the headgear 300 may be determined, at least in part, by the material that the portion is formed from. A degree of stretch of a portion of headgear 300 can relate to a change in length of that portion from its resting length to, or towards, a maximum extended length.

[0179] A resting length of a portion may be the length when there is no tension applied to that portion. For example, the resting length can be the length of a portion of headgear 300 when doffed.

[0180] A maximum extended length of a portion may be the maximum length that the portion can be extended to under tension without permanent deformation (e.g., plastic deformation) occurring. That is, the maximum extended length may be the length at the yield point of that portion. Examples of permanent deformation, as opposed to elastic deformation, include tearing or breaking of the portion, or the portion not resiliently returning to its resting length when the tensile force is removed.

[0181] The degree of stretch of a portion of headgear 300 can be represented by the ratio of its maximum extended length to its resting length. A higher ratio means a greater degree of stretch. And the loop 314 may adopt a wider range of circumferences in use. [0182] A circumferential direction of the loop 314 refers to a direction along, or substantially parallel to, the enclosing boundary of the loop 314. The circumferential direction is generally indicated by the arrow 328 in FIG. 4, FIG. 5 and FIG. 8 (illustrating the circumferential direction 328 of the first side portion 306, upper portion 302 and chin portion 304, respectively). It is not intended to imply that the headgear 300 is necessarily circular. It should be understood that the circumference of loop 314 may have a generally circular profile or may have a non-circular profile. In particular, the headgear 300 will generally conform to, and adopt, the shape of the patient's head when donned, and may therefore adopt an elliptical or reniform shape, for example. When doffed, the loop 314 may adopt any of a range of different shapes, as shown in FIG. 3, FIG. 8 and FIG. 9, for example) but is at least capable of forming a closed loop.

[0183] A degree of stretch of a portion of headgear 300 in the circumferential direction of loop 314 refers to the change in the circumference of the loop 314 due to a change in length of that portion from its resting length to or towards a maximum extended length. A portion with a relatively greater degree of stretch in the circumferential direction of loop 314 results in a correspondingly larger possible circumference of loop 314. Length in a circumferential direction of loop 314 can refer to an arc length of the portion if the circumference has a curved geometric profile such as circular or ovate. In cases where a portion of the headgear 300 comprises a material with anisotropic degrees of stretch, the degree of stretch in the circumferential direction of that portion will depend upon the orientation of the anisotropic material.

[0184] In one example of measuring a degree of stretch in the circumferential direction of the loop 314, the headgear 300 may be doffed and laid flat such that the loop 314 is collapsed whilst still maintaining the couplings between the various portions of the headgear 300. Or loop 314 can be broken, e.g., if two portions of the loop are removably coupled. For the upper portion 302, chin portion 304, first side portion 306, second side portion 308, it can be assumed that an arc length of the portion of the headgear 300 when it is arranged as part of loop 314 is equivalent to the length of that same part in the circumferential direction of loop 314 when it is laid flat or otherwise arranged linearly. The resting length of each of these portions when laid flat may be measured and recorded.

[0185] To measure the maximum extended length of the chin portion 304, one end of the chin portion 304, e.g., coupled to the first side portion 306, may be aligned and held in one grip of a tensile testing machine (such as a universal testing machine). The opposing end of the chin portion 304, e.g., coupled to second side portion 308, can be aligned and held in the other grip of the tensile testing machine. This arrangement, and the length from the first grip to the second grip of the tensile testing machine, may correspond with a circumferential direction of loop 314. A tensile test can then be conducted on the chin portion 304 where the grips are pulled apart until permanent deformation of chin portion 304 occurs. During the test, the tensile testing machine or an observer may record the length of the chin portion 304. The maximum extended length corresponds to the length of the chin portion 304 just before permanent deformation of chin portion 304 occurs (e.g., at the yield point of the portion). The recorded maximum extended length can then be compared to the recorded resting length of chin portion 304 to find the ratio of maximum extended length to resting length. The ratio is representative of the degree of stretch of the chin portion 304 in the circumferential direction of the loop 314.

[0186] The same test methodology as described for the chin portion 304 can be applied and conducted for determining the maximum extended length and the degree of stretch of the upper portion 302, first side portion 306 and/or second side portion 308. The second ends 326 of the adjustment straps may be detached from the upper portion 302 to avoid the adjustment straps influencing the test results.

[0187] For the first adjustment strap 310 and the second adjustment strap 312, the resting length can be determined by doffing the headgear 300, laying the adjustment strap out flat and measuring from the first end 324 to the second end 326. The maximum extended length can be determined using a tensile testing machine, similar to the testing method for the chin portion 304 described above. During the tensile test of the adjustment straps 310, 312, the second end 326 of the adjustment strap may be detached from the upper portion 302 to avoid the upper portion and/or side portion influencing the test results. The first end 324 of the adjustment strap 310, 312 can be held in one grip of the tensile testing machine and the second end 326 can be held in the other grip. The ratio of maximum extended length to resting length can then be determined as described above. The ratio is representative of the degree of stretch of the adjustment strap in the circumferential direction of loop 314.

[0188] The following test can be conducted to assess the selective limiting of the degree of stretch of the first side portion 306 and/or the second side portion 308 in the circumferential direction of loop 314 when adjustment strap 310 is adjustably coupled to the upper portion 302. For this test, the second end 326 of the adjustment strap 310, 312 may be maintained in a position on the upper portion 302 following adjustable coupling. The first adjustment strap 310 may be held in one grip of the tensile testing machine at the location where it is adjustably coupled to the upper portion 302, or at the location where it may overlie the junction between the second side portion 308 and the upper portion 302. The end of the side portion 306, 308 which is coupled to the chin portion 304 can be aligned and held in the other grip of the tensile testing machine. A tensile test can then be conducted where the grips are pulled apart until permanent deformation of either the side portion 306, 308 or the corresponding adjustment strap 310, 312, or another part of the headgear 300 (such as the junctions between the side portions 306, 308 and the upper portion 302) occurs, or the adjustable coupling is disrupted (e.g., fastener 330 slips or fails). The length of the assessed side portion 306, 308 can be recorded when the abovedescribed deformation occurs, or the adjustable coupling is disrupted, and may be considered the maximum extended length of the side portion 306, 308 in this situation. This recorded maximum extended length can then be compared to the recorded resting length of the side portion 306, 308 to find the effective ratio of maximum extended length to resting length. This ratio is representative of the selective limiting of the degree of stretch of the side portion 306, 308 as a result of the adjustable coupling of the adjustment strap 310, 312 to the upper portion 302.

[0189] The adjustable coupling provided by the second ends 326 of the first adjustment strap 310 and the second adjustment strap 312 mean that the coupling of the second end of adjustment strap 310 and upper portion 302 can be adjusted. The position of the second end of adjustment strap 310 relative to upper portion 302 can be changed by a user, e.g. a clinician. Changing the position of the second ends 326 of the adjustment straps 310, 312 relative to upper portion 302 may adjust the tension on adjustment straps, and/or limit the effective degree of stretch of the side portions 306, 308, when the headgear 300 is donned.

[0190] The second ends 326 of the first adjustment strap 310 and the second adjustment strap 312 may have a fastener 330 configured to facilitate the adjustable coupling to the upper portion 302. The fastener 330 may provide for infinitely- adjustable attachment, or attachment in one of a plurality of discrete positions. In the example headgear 300, the fasteners 330 may comprise a region of hook material and the upper portion 302 may comprise an unbroken loop (UBL) fabric configured to provide an infinitely-adjustable hook-and-loop attachment to each other. In other examples, the first adjustment strap 310 and the second adjustment strap 312 and/or the upper portion 302 may comprise alternative fasteners such as corresponding protrusions and recesses (e.g., push or snap domes and corresponding slots), buttons, clips or buckles. In some examples, the fastener 330 may extend along, or in some examples form, the entirety of the adjustment strap.

[0191] The adjustment straps 310, 312 may permit adjustment of the fit of the headgear 300 to the patient while either doffed or donned. For example, tension in the first adjustment straps 310 may be increased during use if it is found that some mouth leak is occurring. The adjustment straps 310, 312 advantageously permit adjustment of the fit of the integrally formed loop 314 after it is donned. A pair of adjustment straps 310, 312 advantageously permits symmetric adjustment of tension in the headgear 300. In some cases, however, the fit may be adjusted by adjusting only one of the first adjustment straps 310. For example, the pair of adjustment straps 310, 312 on opposing sides of the loop 314 may advantageously provide access to at least one of the adjustment straps even if the patient's head is resting upon the other of the pair of adjustment straps, e.g., if the patient is side-sleeping.

[0192] Permanent coupling, or integral forming, of the first ends 324 of the first adjustment strap 310 and the second adjustment strap 312 with the chin portion 304 may advantageously simplify assembly and application of headgear 300 to the patient, and/or ensure that the first adjustment strap 310 and the second adjustment strap 312 are not dropped or misplaced. In other examples, the first adjustment strap 310 and/or second adjustment strap 312 may be split into two or more strap portions, each having a second end which may be adjustably coupled to upper portion 302.

This may beneficially provide further degrees of adjustment to headgear 300. For example, first and/or second adjustment strap 310, 312 may be bifurcated and comprise two strap portions which may each be adjustably coupled to upper portion to selectively limit the degree of stretch, in the circumferential direction, of the associated side portion.

[0193] In the example shown in FIG. 3 to FIG. 9, the first side portion 306 and/or the second side portion 308 may have a greater degree of stretch and/or resilience, in a circumferential direction of the loop 314, than one or more of the chin portion 304, the first adjustment strap 310, the second adjustment strap 312, and/or the upper portion 302.

[0194] In particular, the first side portion 306 and/or the second side portion 308 may have a greater degree of stretch, in a circumferential direction of loop 314, than the corresponding first adjustment strap 310 and/or second adjustment strap 312. In the example headgear 300 of FIG. 3 to FIG. 9, both the first side portion 306 and the second side portion 308 may have a greater degree of stretch than each of the first adjustment strap 310 and second adjustment strap 312.

[0195] The first adjustment strap 310 and second adjustment strap 312 may have a lower degree of stretch than the corresponding first side portion 306 and second side portion 308, and are configured to be arranged in parallel therewith. Because of this, a second end of each of the first adjustment strap 310 and second adjustment strap 312 can be adjustably coupled to the upper portion 302 to selectively limit the effective degree of stretch of the corresponding side portion, and thus the degree of stretch of the loop 314 as a whole, in the circumferential direction. [0196] The first side portion 306 and/or the second side portion 308 may have a greater degree of stretch and/or resilience in the circumferential direction than the chin portion 304 and/or the upper portion 302. In the example shown in FIG. 3 to FIG. 9, both the first side portion 306 and second side portion 308 have a greater degree of stretch, in a circumferential direction of loop 314, than each of the chin portion 304 and upper portion 302. Since the adjustment straps 310, 312 may be integrally formed with the chin portion 304 from one continuous piece of material, and may have substantially the same width, the degree of stretch of the chin portion 304, first adjustment strap 310 and second adjustment strap 312 in this example may be substantially the same.

[0197] The first side portion 306 and the second side portion 308 having a greater degree of stretch in the circumferential direction of loop 314 than each of the chin portion 304 and the upper portion 302 may be beneficial when applying headgear 300 to a patient. When the loop 314 of headgear 300 is applied to a patient, the greater degree of stretch of the first side portion 306 and second side portion 308 may improve the conformity of headgear 300 to the patient. Particularly with the second ends of one or more of the adjustment straps 310, 312 detached from the loop 314. Conformity may be improved as the size of the loop 314 can stretch and change to fit and match the head of the patient, due to the resulting change in length of the side portions 306, 308. This may improve patient comfort, improve the ease of fitting headgear 300 to the patient, accommodate a wider range of patient head sizes, and/or contribute to quick donning of the headgear 300.

[0198] In some examples, the degree of stretch of the first side portion 306 and/or the second side portion 308 in the circumferential direction of the loop 314 may be such that their ratio of maximum extended length to resting length may be greater than 1.5: 1. In some examples, the ratio may be between about 1.5: 1 and 2: 1. That is, that the side portion is capable of being extended to a length that is between about 1.5 times and about 2 times its resting length (in other words, between about 150% and 200% of the resting length) without permanent deformation. For example, the ratio of maximum extended length to resting length of the side portion may be about 1.5: 1, 1.6: 1, 1.7: 1, 1.8: 1, 1.9: 1 or 2: 1. In some examples, the ratio of maximum extended length to resting length of the first side portion 306 and/or the second side portion 308 may be between about 1.6: 1 and 1.9: 1, or between about 1.7: 1 and 1.8: 1. In some examples, the degree of stretch of the first side portion 306 or the second side portion 308 in the circumferential direction of the loop 314 may be such that the circumference of the loop 314 can increase to between about 105-150%, or between about 115%-140%, or between about 125%-130%, of the resting loop circumference (assuming no change in length of the other portions). [0199] In some examples, the degree of stretch of the chin portion 304 in the circumferential direction of the loop 314 may be such that the ratio of maximum extended length to resting length of the chin portion 304 is between about 1 : 1 and 1.1 : 1. That is, the chin portion 304 may be capable of being extended to a length that is up to about 1.1 times its resting length (in other words, between about 100% and 110% of the resting length) without permanent deformation. For example, the ratio of maximum extended length to resting length of the chin portion 304 may be about 1 : 1, 1.05 : 1 or 1.1 : 1. In some examples, the degree of stretch of the chin portion 304 in the circumferential direction of the loop 314 may be such that the circumference of the loop 314 can increase to between about 100-105%, e.g., about 103%, of the resting loop circumference (assuming no change in length of the other portions).

[0200] A ratio of 1 : 1 may indicate that the relevant portion of the headgear cannot stretch, or stretches only negligibly, within a range of ferees which might be expected to be encountered during normal use, e.g., up to about 20 N. That is, the portion stretches no more than negligibly when subjected to a tensile force of about 20N. For the purposes of this disclosure, inextensibility is regarded as a degree of stretch (i.e., zero degree of stretch) rather than an absence of a degree of stretch.

[0201] The degree of stretch of the upper portion 302 in the circumferential direction of the loop 314 may be such that the ratio of maximum extended length to resting length of the upper portion 302 is between about 1 : 1 and 1.1 : 1. That is, the upper portion 302 is capable of being extended to a length that is up to about 1.1 times its resting length (in other words, between about 100% and 110% of the resting length) without permanent deformation. For example, the ratio of maximum extended length to resting length of upper portion 302 may be about 1 : 1, 1.05: 1 or 1.1 : 1. In some examples, the degree of stretch of the upper portion 302 in the circumferential direction of the loop 314 may be such that the circumference of the loop 314 can increase to between about 100-105%, e.g., about 103% of the resting loop circumference (assuming no change in length of the other portions).

[0202] The degree of stretch of the first adjustment strap 310 and/or the second adjustment strap 312 in the circumferential direction of the loop 314 may be such that the ratio of maximum extended length to resting length of the adjustment strap is between about 1 : 1 and 1.1: 1. That is, the adjustment strap is capable of being extended to a length that is up to about 1.1 times its resting length (in other words, between about 100% and 110% of the resting length) without permanent deformation. For example, the ratio of maximum extended length to resting length of the adjustment strap may be about 1 : 1, 1.05: 1 or 1.1 : 1. [0203] In some examples, the ratios of maximum extended length to resting length of any two or more of the chin portion 304, the upper portion 302, the first adjustment strap 310, and the second adjustment strap 312 may be within 5% of each other, or substantially the same. For example, the chin portion 304, the first adjustment strap 310, and the second adjustment strap 312 may be formed from the same material (i.e., having the same stretch properties). In the example headgear 300 of FIG. 3 to FIG. 9, the chin portion 304, first adjustment strap 310 and the second adjustment strap 312 may be integrally formed from one continuous length of material. And they may each have substantially the same ratios of maximum extended length to resting length.

[0204] In some examples, one or more of the upper portion 302, chin portion 304, first adjustment strap 310 and second adjustment strap 312 may be substantially inextensible.

[0205] In some examples, one or more of the upper portion 302, chin portion 304, first side portion 306, second side portion 308, first adjustment strap 310 and second adjustment strap 312 may have anisotropic stretch properties. That is, these portions may have the stretch properties discussed above in the circumferential direction of loop 314, but could have different stretch properties in other directions (in particular, in a direction transverse to the circumferential direction). The stretch properties may include the degree of stretch and the ratio of maximum extended length to resting length, as described herein.

[0206] In some examples one or more of the upper portion 302, chin portion 304, first side portion 306, second side portion 308, first adjustment strap 310 and second adjustment strap 312 may have substantially isotropic stretch properties.

[0207] In some examples, the headgear 300 may comprise an adjustment strap associated with one side portion but not with the other side portion. For example, headgear 300 may be provided with only a single adjustment strap. That is, an adjustment strap may be associated with either the first side portion 306 or the second side portion 308 and may function as first adjustment strap 310 or second adjustment strap 312. The adjustment strap is configured to be adjustably coupled to the loop to selectively limit the degree of stretch of the associated side portion, in the circumferential direction, in use. This example may be beneficial for usability as it provides one location for adjustment.

[0208] In such examples, the side portion which is associated with the single adjustment strap may have a greater degree of stretch, in the circumferential direction of loop 314, than the side portion which is not associated with any adjustment strap. The side portion which is not associated with the adjustment strap may have substantially the same degree of stretch, in the circumferential direction of loop 314, as chin portion 304 and/or upper portion 302 and/or the adjustment strap. In some examples, the side portion which is not associated with the adjustment strap may be made from the same material as the chin portion 304 and the single adjustment strap. In some examples, the side portion which is not associated with the adjustment strap may be integrally formed in one piece with the chin portion 304 and optionally the adjustment strap.

[0209] In some examples comprising a single adjustment strap, the side portion which is not associated with the adjustment strap may have a degree of stretch in the circumferential direction of the loop 314 such that the ratio of maximum extended length to resting length of that side portion is between about 1 : 1 and 1.1 : 1. That is, the side portion is capable of being extended to a length that is between its resting length and about 1.1 times its resting length (in other words, between about 100% and 110% of the resting length) without permanent deformation. For example, the ratio of maximum extended length to resting length of the side portion may be about 1 : 1, 1.05: 1 or 1.1 : 1.

[0210] In the example headgear 300 of FIG. 3 to FIG. 9, the chin portion 304 and upper portion 302 may be formed from different materials, e.g., having different stretch properties. The upper portion 302 may be formed from a material that has anisotropic stretch. In some examples, the anisotropic material may have a relatively greater degree of stretch in a direction other than the circumferential direction. The anisotropic material may have a relatively greater degree of stretch in a direction transverse to the circumferential direction of the loop 314, i.e., in a direction from the front of the patient's head to the back of the head (parallel to the sagittal plane), in use. A relatively greater degree of stretch may be beneficial when applying headgear 300 to the patient as upper portion 302 can conform to the patient's head. This may provide a more stable and secure fitting. In other examples, the chin portion 304 and the upper portion 302 may each be formed from the same material and/or a substantially isotropic stretch material.

[0211] One or more of the upper portion 302, chin portion 304, first side portion 306, second side portion 308, first adjustment strap 310 and second adjustment strap 312 may be formed at least in part from a spandex (elastane) (e.g., Lycra™), cotton and/or nylon material. These materials may be configured to provide the degrees of stretch which are described herein.

[0212] In the example of FIG. 3 to FIG. 9, a user can adjust the coupling of the second ends 326 of the first adjustment strap 310 and second adjustment strap 312 with the upper portion 302 such that the second ends 326 are in a desired location on the upper portion 302. This can result in the selective limiting of the degree of stretch of the side portions 306, 308, in the circumferential direction of the loop 314. This may happen because the first side portion 306 and second side portion 308 are located between the chin portion 304 and upper portion 302. The first adjustment strap 310 and second adjustment strap 312 may be coupled to both the chin portion 304 and the upper portion 302 which limits the movement of chin portion 304 and upper portion 302 relative to each other, and stretching of the first side portion 306 and second side portion 308. That is, the effective maximum extended length of the first side portion 306 and/or second side portion 308 may be adjusted by repositioning the corresponding first adjustment strap 310 and/or second adjustment strap 312. There may be a reduction of mouth leak by selectively limiting the effective degree of stretch of the side portions 306, 308 in the circumferential direction of loop 314 by adjustably coupling the second ends 326 with the upper portion 302. Or an improvement in patient comfort by permitting a greater effective degree of stretch in the side portions 306, 308.

[0213] The second ends 326 of the first adjustment strap 310 and/or second adjustment strap 312 may be adjustably coupled to the upper portion 302 to limit the degree of stretch of the corresponding first side portion 306 and/or second side portion 308 in the circumferential direction of loop 314. In at least one configuration, this limiting may be such that the effective ratio of maximum extended length to resting length of the side portion may be substantially the same as that of the corresponding adjustment strap, for example between about 1: 1 and 1.1 : 1 or about 1.05: 1. That is, the adjustment straps 310, 312 may be capable of being attached to the upper portion 302 in a position which selectively limits extension of the corresponding side portions 306, 308 from their resting length to somewhere between their resting length and about 1.1 times their resting length (in other words, between about 100% and 110% of the resting length of the side portion), depending on the degree of stretch of the adjustment strap. As above, the maximum extended length of the side portion 306, 308 here refers to a length the side portion(s) may extend when the adjustment strap is adjustably coupled to the upper portion 302 and does not necessarily represent a maximum length before deformation of the side portion 306, 308.

[0214] The degree of stretch of the side portion, when limited by an adjustment strap, may be referred to as an effective degree of stretch. It will be appreciated that a relatively higher effective degree of stretch in the side portions may be selectively obtained by adjusting the position of the second end 326 of the corresponding adjustment strap. That is, the adjustment straps 310, 312 may optionally be positioned to enable the first side portion 306 and/or the second side portion 308 to stretch further, e.g., beyond a ratio of 1.1 : 1, before the corresponding adjustment strap comes under tension to "lock out" the stretch of the side portion. In some examples, a position of the second ends 326 of the first adjustment strap 310 and/or the second adjustment strap 312 may be adjusted such that the effective ratio of maximum extended length to resting length of the corresponding side portion may be anywhere between the ratio of the adjustment straps 310, 312 and the ratio of the side portion. In some examples, the effective ratio may be adjusted anywhere within the range of about 1 : 1 to 2: 1, 1.1: 1 to 2: 1, 1 : 1 to 1 : 1.5, or 1.1: 1 to 1.5: 1.

[0215] The example headgear 300 of FIG. 3 to FIG. 9 may be sized so as to be suitable for use by an infant patient. For example, the headgear 300 may have resting lengths in the circumferential direction of the loop 314 of between about:

• 5 and 10 centimeters (cm) for the chin portion 304;

• 5 and 15 cm for each of the first side portion 306 and the second side portion 308;

• 5 and 10 cm for the upper portion 302;

• 10 and 16 cm for each of the first adjustment strap 310 and the second adjustment strap 312; and

• 20 and 50 cm for the loop 314 as a whole (loop circumference).

[0216] The above ranges of resting lengths are provided as an example for the headgear 300 having the degrees of stretch described above. It is not intended that all examples of headgear according to the disclosure will necessarily have degrees of stretch and/or resting lengths within the above ranges. There are many factors which may impact the chosen resting lengths of the various portions of the headgear. For example, different lengths of different materials may have the same stretch properties (including the degree of stretch in the circumferential direction of loop 314), and/or the same maximum extended length. Two different examples of headgear according to the present disclosure could have the same loop circumference (i.e., loop resting length) and stretch properties, but different portion lengths. For example, the resting lengths of the side portions may differ between the two headgears.

[0217] It is to be understood that any one or more of the above ranges of resting lengths could be suitably altered depending on material and patient size. For example, a headgear example according to the disclosure could instead be sized for an adult respiratory support setting, such as use during the provision of CPAP therapy to an adult patient. Such a headgear might have a chin portion, side portions, upper portion, and adjustment straps exceeding one or more, and possibly all, of the above resting length ranges. [0218] The first adjustment strap 310 and the second adjustment strap 312 may each have a resting length in the circumferential direction of the loop 314 which is suitable to allow the second ends 326 to be adjustably coupled to the upper portion 302 in a variety of different positions, in use. In some examples, the resting lengths of the first adjustment strap 310 and second adjustment strap 312 may be longer than those of the corresponding first side portion 306 and second side portion 308. In some examples, the first adjustment strap 310 and second adjustment strap 312 may be longer than the maximum extended length of the corresponding side portions 306, 308. The first adjustment strap 310 and second adjustment strap 312 may have a resting length which is shorter than a sum of the maximum extended length of the corresponding side portion plus half the maximum extended length of the upper portion 302, in the circumferential direction. This may reduce the likelihood of the adjustment straps 310, 312 overlapping at the upper portion 302, in use. In some examples, the first adjustment strap 310 and second adjustment strap 312 may each be shorter than a sum of the resting length of the corresponding side portion plus half the resting length of the upper portion 302, in the circumferential direction.

[0219] In some examples, the adjustment straps 310, 312 may be configured so that adjustably coupling the second ends 326 of the adjustment straps 310, 312 towards, e.g., at or about, a middle of the upper portion 302 may permit relatively little, if any, stretch in the side portions 306, 308, in use. In one example, extending and attaching the second ends 326 of the adjustment straps 310, 312 as far along the upper portion 302 as possible with the corresponding side portion at its resting length may minimize the effective degree of stretch of the corresponding first side portions. Adjustably coupling the second ends 326 of the adjustment straps 310, 312 to the upper portion 302 at or adjacent the respective junction between the upper portion 302 and the corresponding side portion, on the other hand, may allow for relatively greater stretch of the side portions 306, 308. In some examples, the side portions 306, 308 may be permitted to stretch to their maximum extended length, or within about 5% or about 10% of their maximum extended length, in this configuration. When headgear 300 is in such a configuration, a clinician may choose to alter the adjustable coupling of the second ends 326 of adjustment straps 310, 312 to achieve a desired effective degree of stretch of the side portions 306, 308. For example, the clinician may move the second ends 326 of adjustment straps 310, 312 towards a middle of the upper portion 302 to limit or reduce the stretch of the respective side portions 306, 308.

[0220] FIG. 4 illustrates a side view of the headgear 300 when donned by a patient 102. The arrow 328 indicates the general orientation of the circumferential direction for the first side portion 306. The direction shown will follow loop 314 and is dependent on how headgear 300 and loop 314 is fitted on the patient 102. [0221] As shown in FIG. 4, the first adjustment strap 310 may extend over the first side portion 306 with its second end 326 adjustably coupled to the upper portion 302. The first adjustment strap 310 may be configured to avoid contact with the patient's ear 402. In some examples, as illustrated, a width (e.g., in a direction transverse to the circumferential direction) of the first side portion 306 may be greater than a width of the first adjustment strap 310. This can beneficially protect the skin of the patient from direct contact with the first adjustment strap 310. This may be particularly advantageous for patients with delicate skin, e.g., infant patients. Tension may be applied to the first adjustment strap 310 when the headgear 300 is donned by the patient, in use. This tension in the first adjustment strap 310 may cause skin damage or skin irritation if first adjustment strap 310 were to directly contact the patient's head. In some examples, a width of the first side portion 306, at its widest point, may be at least about 200%, or at least about 300%, or between about 300% and 400%, of the width of first adjustment strap 310 at that same point.

[0222] As also shown in this drawing, the first side portion 306 may be configured to at least partially cover the patient's ear 402, which may provide one or more of the benefits of: ameliorating abrasion between an edge of the first adjustment strap 310 and the patient's ear 402; providing physical protection from contact between the ear 402 and other components which may be present in a hospital setting during provision of respiratory support; providing noise protection from noises present in the hospital setting, if the material the side portion is made of, or has, noise absorbing properties; and/or providing additional thermal insulation to the patient.

[0223] The second side portion 308 and the second adjustment strap 312 may each be a mirror image of the respective first side portion 306 and first adjustment strap 310. In some examples and configurations, the headgear 300 may be symmetric (that is, having reflective symmetry) about a sagittal plane.

[0224] FIG. 5 illustrates a top view of the headgear 300 when donned by the patient 102. The arrow 328 indicates the general orientation of the circumferential direction for the upper portion 302.

[0225] It can be observed that the second ends 326 of each of the first adjustment strap 310 and second adjustment strap 312 are adjustably attached to an outer-facing surface 332 of the upper portion 302. In some examples, the second ends 326 may be attached relatively near the junctions between the upper portion 302 and the respective side portions 306, 308, as illustrated. This configuration may provide for a relatively greater degree of stretch in each of the first side portion 306 and second side portion 308 than if the second ends 326 were positioned closer together, towards a center (in the circumferential direction) of the upper portion 302. And this configuration may provide for a wider range of adjustability should further tension be required to address mouth leak.

[0226] FIG. 6 illustrate a high angle front view of the headgear 300 when donned by the patient 102. It can be observed that the headgear 300 avoids the nasal bridge, naris, nasal septum, philtrum and nasolabilal sulcus regions of the patient's face. Avoiding one or more of these areas may aid effective sealing of a patient interface (e.g., a nasal mask or nasal pillows) with the patient's airways.

[0227] FIG. 7 illustrates a low angle front view of the headgear 300 when donned by the patient 102.

[0228] The chin portion 304 is configured to engage the chin 602 of the patient 102 in use. The chin portion 304 may comprise a longitudinal slit 334 to increase stability of chin portion 304 in use, as best shown in FIG. 6 and FIG. 7. Slit 334 is positioned to align with the patient's chin and may allow the chin portion 304 to better conform around the patient's mental protuberance. For example, the slit 334 may be positioned in the middle of chin portion 304, as shown in FIG. 7. A portion, e.g., half, of a section of the chin portion 304 adjacent the slit 334 may engage a front of the patient's mental protuberance. Another portion, e.g., the other half, of the section of the chin portion 304 adjacent the slit 334 may engage an underside of the patient's mental protuberance. Additionally, or alternatively, the chin portion 304 may comprise a chin cup (not shown) to increase stability of the chin portion 304 in use. A chin cup may define a concave surface that can receive and grip a portion of the patient's chin in use. The chin cup may be molded from a plastic material, for example.

[0229] FIG. 8 provides a detail view of the loop 314 of the example headgear 300 when doffed, including a patient-contacting surface 336 of the chin portion 304 and an outer-facing surface 332 of the upper portion 302.

[0230] The arrow 328 indicates the general orientation of the circumferential direction for the chin portion 304.

[0231] The outer-facing surface 332 of the upper portion 302 may comprise a UBL fabric to facilitate adjustable engagement of the fasteners 330 of adjustment straps 310, 312. In other examples, the upper portion 302 may be provided with a complementary fastener which may be stitched or welded to the upper portion 302, for example. [0232] When arranged to form the loop 314, each of the first side portion 306 and the second side portion 308 may be coupled to the chin portion 304 at a respective first lower junction 316 and second lower junction 318. And may be coupled to the upper portion 302 at a respective first upper junction 320 and second upper junction 322. The first ends 324 of the first adjustment strap 310 and the second adjustment strap 312 extend from the loop 314 at the respective first lower junction 316 and second lower junction 318. In other examples, the first ends 324 of the first adjustment strap 310 and the second adjustment strap 312 may extend from the loop 314 at the respective first upper junction 320 and second upper junction 322.

[0233] As described above, the first ends 324 of the first adjustment strap 310 and the second adjustment strap 312 can be permanently or removably coupled with the respective first lower junction 316 and second lower junction 318 (between the respective side portion and the chin portion 304). In some examples, e.g., as shown in FIG. 3 to FIG. 9, the first ends 324 of the first adjustment strap 310 and the second adjustment strap 312 may be permanently coupled with the side portions at the respective first lower junction 316 and second lower junction 318 as the adjustment straps 310, 312 may be integrally formed with the chin portion 304. The first side portion 306 may be permanently joined to the chin portion 304 and the first adjustment strap 310 by stitching at the first lower junction 316. The second side portion 308 may be permanently joined to the chin portion 304 and the second adjustment strap 312 by stitching at the second lower junction 318.

[0234] The upper portion 302 may be permanently joined to the first side portion 306 and the second side portion 308 by stitching at the respective first upper junction 320 and second upper junction 322. But other methods of permanent coupling, may be utilized for any one or more of the junctions 316, 318, 320, 322, as described above.

[0235] In some examples, an edge (e.g., a minor edge) of each of the first side portion 306 and second side portion 308 which is coupled with the upper portion 302 may be formed to have a convex profile. Other edge profiles may also be suitable to perform a similar function as described for the convex profile, such as other profiles having a central portion of the edge which extends outward (e.g., angled portions of the edge can extend outward towards a point). The upper end of the side portions 306, 308 may be pre-formed (e.g., by die-cutting the side portion from a sheet of material, or cutting the side portion from a length of material) so as to have a convex profile. The edge having the convex profile may join to the upper portion 302 at the respective first upper junction 320 or second upper junction 322. In some examples, as shown in FIG. 8, the edges of the first side portion 306 and the second side portion 308 which respectively join to the upper portion 302 at the first upper junction 320 and second upper junction 322 may each have a convex profile. In some examples, the convex profile may be joined to a straight edge of the upper portion 302.

[0236] The convex profile may beneficially reduce the likelihood of the free edges (e.g., the major edges extending in the circumferential direction of the loop 308) of the upper portion 302 and/or the side portions 306, 308 lifting up and off the patient's head when the headgear is fitted. This lifting may otherwise happen due to the headgear 300 not matching the curvature of the patient's head. This lifting off may be reduced due to the convex profile, when coupled to the upper portion 302, inducing a shape or curvature in the headgear 300 in the transverse direction, which may approximate the shape or curvature of the patient's head in a direction from the frontal bone to the occipital bone of the patient. The shape or curvature may assist the upper portion in cradling an upper rear portion of the patient's head, and may beneficially ameliorate slippage of the upper portion 302 forwardly towards the patient's frontal bone and/or downwardly towards the patient's occipital bone. Additionally, or alternatively, in some examples the one or more of the edges of the upper portion 302 which join with the first side portion 306 or second side portion 308 may have a convex profile. For example, the minor edges of the upper portion 302 may have a convex profile and join with respective straight edges of the first side portion 306 and the second side portion 308 at the first upper junction 320 and the second upper junction 322.

[0237] FIG. 9 provides a detail view of the loop 314 of the example headgear 300 when doffed, including the patient-contacting surface 336 of the chin portion 304 and a patient-contacting surface 338 of the upper portion 302.

[0238] In some examples, at least one of the patient-contacting surface 336 of the chin portion 304 and the patient-contacting surface 338 of the upper portion 302 may comprise one or more friction members. The friction members may comprise one or more regions of tacky material. The tacky material may increase the friction between the headgear 300 and the patient's head, which may ameliorate potential skin damage to the patient's head from movement of headgear 300 and/or slippage of the headgear 300. The tacky material may comprise at least one of:

• a tape comprising a polyurethane adhesive film and a polyurethane elastic barrier (e.g., suitable tapes are available from Bemis Associates Inc.),

• neoprene,

• silicone,

• thermoplastic polyurethane, polyester or co-polyolefin,

• co-polyamide, and

• ethylene vinyl acetate co-polymer thermoplastic. [0239] The one or more regions of tacky material may be heat pressed onto the patient-contacting surface 336 of the chin portion 304 and/or the patient-contacting surface 338 of the upper portion 302.

[0240] The one or more regions of tacky material may be located at or adjacent at least one of the first lower junction 316 and the second lower junction 318 between the chin portion and the respective side portions 306, 308. Additionally, or alternatively, the one or more regions of tacky material may be located at or adjacent at least one of the first upper junction 320 and the second upper junction 322 between the upper portion 302 and the respective side portions 306, 308. Having tacky material at or adjacent these junctions may be beneficial as these are the points of contact of the headgear 300 which may be more likely to move or slip relative to the patient's head, in use, and/or have stitching or other fastenings which may irritate the patient's skin. The tacky material increases the friction with the patient's head at these junctions which may stabilize the headgear 300 at these points of contact, reducing or minimizing skin damage or skin irritation caused by movement at these points of contact.

[0241] The application of one or more regions of tacky material may impact the degree of stretch of the corresponding chin portion 304 and/or upper portion 302. Generally, application of one or more regions of tacky material to a portion may decrease the degree of stretch of that portion. When such tacky materials are present, the aforementioned degrees of stretch in the circumferential direction of the loop 308 refer to the corresponding portion of the headgear 300 with the tacky material included. The impact upon the degree of stretch in the circumferential direction may be controlled by applying the one or more regions of tacky material in a particular pattern. For example, a pattern of narrow strips extending in the transverse direction may ameliorate the impact upon the degree of stretch in the circumferential direction, when compared to a single contiguous planar region of tacky material. Or a polka dot pattern of tacky material may ameliorate, or balance, the impact upon the degree of stretch in both the circumferential direction and the transverse direction.

[0242] As shown in FIG. 9, the first side portion 306 and/or the second side portion 308 may taper. The side portions 306, 308 may have a width in the region near upper portion 302 (e.g., at the respective first upper junction 320 and second upper junction 322) which is greater than the width of the side portion in the region near chin portion 304 (e.g., at the respective first lower junction 316 and second lower junction 318). The upper portion 302 may have a width which is greater than chin portion 304. The width of the side portions may be the same as the width of the upper portion 302 at or adjacent the respective first upper junction 320 and second upper junction 322. The width of the side portions may be the same as the width of the chin portion 304 at or adjacent the respective first lower junction 316 and second lower junction 318.

[0243] In some examples, the width of the first side portion 306 and/or second side portion 308 may taper from the region near the upper portion 302 to the region near the chin portion 304. The first side portion 306 may taper from a width of the upper portion 302 to a width of the chin portion 304. This can reduce the profile of the first side portion 306, particularly on the lower part of the patient's face. A reduced profile on the lower part of the patient's face may provide more space on the patient's face for the patient interface 112 to be positioned and to seal with the patient's skin for provision of respiratory therapy. A reduced profile of the side portions 306, 308 may also beneficially improve visibility of the patient's face. This may be valued by parents of infant patients wishing to observe their child, for example. The side portion may taper continuously from the upper portion 302 to the chin portion 304.

[0244] In some examples, a lower edge (that is, a lower end) of the first side portion 306 and/or second side portion 308 may be bunched (e.g., gathered) together where the lower edge joins to the chin portion 304. The bunching may allow the side portion to have a greater width than the width of the chin portion 304 in a region near chin portion 304. This may improve stability of the headgear 300 on the patient whilst also providing a tidy coupling between the side portion and the chin portion 304.

[0245] Bunching of the side portions 306, 308 may permit the side portions 306, 308 to be formed by cutting an elongate length of suitable material of generally uniform width, such as the width of the upper portion 302. And the side portions 306, 308 may still be tapered upon attaching the material to the narrower chin portion by bunching the material together at the respective first lower junction 316 or second lower junction 318, as described above.

[0246] In use, the example headgear 300 of FIG. 3 to FIG. 9 in some examples may be applied to an infant patient by a clinician to aid in the provision of bubble CPAP therapy to the infant.

[0247] Before donning, the second ends 326 of the first adjustment strap 310 and second adjustment strap 312 may be detached from the upper portion 302. That is, the adjustment straps 310, 312 may be in the non-attached configuration.

[0248] The loop 314 formed by the chin portion 304, the first side portion 306, the second side portion 308 and the upper portion 302, is then fitted over and around the head of the infant patient. The loop 314 may be fitted such that the chin portion 304 engages the patient's chin, the upper portion 302 engages at least part of one or more of the patient's frontal, parietal and occipital bones, and the first side portion 306 and the second side portion 308 each engage a respective side of the patient's head. The entire loop 314 in the example headgear 300 of FIG. 3 to FIG. 9 may be permanently coupled (i.e., forming a permanent loop). The permanent loop 314 may result in a more convenient application to, and/or removal from, the patient of the headgear 300. As the degree of stretch of the side portions 306, 308 is greater than those of the chin portion 304 and the upper portion 302, the loop 314 may readily deform to receive the patient's head within the loop, and may elastically recover to conform to the patient's head.

[0249] Once the headgear 300 is donned by the patient, the second ends 326 of the first adjustment strap 310 and/or the second adjustment strap 312 may be gripped by the clinician and adjustably coupled to the upper portion 302 via fasteners 330. This adjustable coupling is done by the clinician increase tension in the loop 314 and/or to selectively limit the degree of stretch of side portions 306, 308. Attachment of the adjustment straps 312, 314 may secure and stabilize the headgear 300 on the infant such that the mouth of the patient is urged closed and/or inhibited from opening.

With the mouth urged closed and headgear 300 secured on the infant, mouth leak may be reduced when bubble CPAP therapy is provided.

[0250] If mouth leaks are found to occur during delivery of respiratory support, tension in the first adjustment strap 310 and/or second adjustment strap 312 may be increased. This may be done by detaching the respective second ends 326 thereof and reattaching them to the upper portion 302 in a different position. This may reduce the effective degree of stretch of the corresponding first side portion 306 and/or second side portion 308, and/or tighten the loop 314 of the headgear 300 upon the patient. Conversely, tension in the adjustment straps 310, 312 may optionally be relieved, e.g., if it is found that there is no mouth leak. Relieving tension in the adjustment straps 310, 312 may improve patient comfort.

[0251] It is to be appreciated that headgear according to the present disclosure may have other uses which may or may not be related to the provision of bubble CPAP therapy to an infant patient. For example, the headgear 300 may be used for the provision of CPAP therapy to an adult patient and may be similarly applied and secured by either a clinician or by the adult patient themselves.

[0252] In further examples, a patient interface assembly may be provided for delivering respiratory support to the patient. The patient interface assembly may comprise a patient interface 112 and headgear according to the present disclosure, such as the example headgear 300 of FIG. 3 to FIG. 9. The patient interface 112 configured to deliver a flow of gases to the patient 102, e.g., at a constant, bi-level or automatic pressure. In some examples, the headgear 300 can be donned independently of the patient interface 112. That is, the patient interface assembly is not attachable to the headgear 300. This can isolate the headgear 300 from any resultant forces caused by the use of the patient interface 112. Instead, the patient interface 112 may be attached to the patient by alternative methods such as by connection to the additional headgear (such as one or more of a bonnet, a beanie, a cap or a strap assembly), or by attachment to the patient's skin by a dermal patch, an adhesive or two-part releasable attachment or connection arrangement or another suitable method. For example, the patient interface 112 may comprise one or more dermal patches and these dermal patches may be attached to one or more cheeks of a patient to secure the patient interface 112 to the patient.

[0253] In further examples a kit may be provided for a respiratory support system. The kit may comprise a patient interface 112 and a headgear according to the present disclosure, such as the example headgear 300 of FIG. 3 to FIG. 9. The kit may comprise a resistance device such as the bubbler 118. The kit may comprise at least one inspiratory conduit 110. The kit may comprise at least one expiratory conduit 116. The kit may comprise an additional headgear such as one or more of a bonnet, a beanie, a cap or a strap assembly.

LISTING OF DRAWING ELEMENTS

100 respiratory support system 102 patient 104 gases source 106 humidifier supply conduit 108 humidifier 110 inspiratory conduit 112 patient interface 114 headgear 116 expiratory conduit 118 bubbler 120 stand 200 respiratory support system 202 heater wire 300 headgear 302 upper portion 304 chin portion 306 first side portion 308 second side portion 310 first adjustment strap 312 second adjustment strap loop first lower junction second lower junction first upper junction second upper junction first end second end circumferential direction fastener outer-facing surface slit patient-contacting surface patient-contacting surface ear chin