Patent Description:
There are many forms of patient interfaces for delivery of gases to a user, such as for example full face masks, oro-nasal masks, nasal masks and nasal cannula.

There are a significant variety of patient interfaces available to users, each of which may have their own stability issues.

Stability of an interface upon a user is of importance for at least the reasons of comfort and maintenance of a desired therapy delivery to the user.

Instability of an interface may lead to dislodgment of an interface or components of the interface which may affect the desired delivery or integrity of therapy for the user.

In various modes, instability of an interface upon a user may be, for example, the result of loading such as by a user speaking and changing the geometry of their face to which the interface is positioned. Facial geometry, such as that of humans, varies greatly due to a large range of factors. These factors may include, but are not limited to, gender, age, or particular medical conditions. Incorrect sizing and geometry of an interface to a particular user may also adversely affect the stability and usability of certain patient interfaces.

In terms of facial movement, when a user speaks, eats, cries or has their facial features distorted or exaggerated, such movement can affect the stability of a patient interface or components of the interface on a user, for example such as a nasal prong or a pair of such prongs of a nasal cannula which may inadvertently come out of a gas delivery position for delivering gas to the nare(s) of a user's nose. More prolonged changes to facial features can also arise from aspects such as a user's position, for example while sleeping. Long term changes in geometry can also occur from user growth and injury recovery.

In relation to the above, it will be appreciated that either due to changes in geometry of a user to which the patient interface is located, or for example by yet other forces, such as by a user pulling on a tube or the interface or other components attached to these, forces or movements can be transmitted to the interface and components thereof. The application of such forces can pose problems of stability, comfort and operational use of the patient interface for a user.

It is therefore an object of the present invention to provide a patient interface, for example such as a nasal cannula, which will go at least some way towards addressing the foregoing problems or which will at least provide the industry/public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

<CIT> relates to a variable CPAP respiratory interface having first and second elbow joints, each free to rotate about an axis extending through a first end thereof.

The present invention provides a nasal interface as claimed.

In a first aspect, the present disclosure may broadly consist in a patient interface, such as a nasal cannula, comprising.

Preferably the element facilitates the reduction in transfer of a force or movement, or both, applied to at least a first region of the interface from being transferred to at least another region of the interface.

Preferably the element responds in a manner to localise the force or the movement, or both, experienced by the at least first region.

Preferably the element responds to minimise or prevent transfer of the force or the movement, or both, from the at least first region to at least one other region of the patient interface.

Preferably the element responds in a manner to maintain the at least one (and preferably the pair of) nasal prong(s) in the configuration of insertion in a nare or nares of the user's nose, or in the configuration of directing a flow of gas toward a nare or nares of the user's nose.

Preferably the response is such that the at least one (or preferably the pair of) nasal prong(s) maintain a stable position within or adjacent to the nares of a user's nose to which the prong(s) is directed.

Preferably the response is such that the interface maintains an operational position upon the user.

Preferably the response is such that the interface maintains a stabile position upon the user.

Preferably the force or movement, or both, experienced by at least a first region of the interface are either, or both, of:.

Preferably the element is deformable or deformed in response to the force or movement, or both, being experienced by at least the first region of the interface.

Preferably the element has a predetermined or preferential mode of deformation in response to an applied force or movement, or both, being experienced by at least a first region of the interface.

Preferably the element is deformable by one or a combination of a compression or a tension or a torsion or bending or other flexion.

Preferably the element responds to the force or movement, or both, experienced by at least the first region of the interface by one or a combination of: changing shape, changing position, changing configuration or deforming.

Preferably the element comprises one or a combination of any of the following:.

Preferably the element is one or more of the following:.

Preferably the element provides for a de-coupling of forces or movement (or both) which is applied to at least the first region of the interface from being transferred to at least one other region of the interface.

Preferably the element provides or is operable or works to prevent or minimise transfer of force of movement from the at least first region of the interface to at least one other region of the interface.

Preferably the element may be a structure or a mechanism of the interface or may be a region of the interface.

Preferably the element is deformable about at least one axis or at least one plane.

Preferably the element is deformable about a preferential first geometry.

Preferably there are two or more elements are located about the interface.

Preferably elements are connected together in a manner so as to provide for a combined response to the force or movement (or both).

Preferably element may respond to the force or movement (or both) in a different mode, thereby providing for a combined response.

Preferably elements are operatively coupled to each other, or to other portions of the interface to provide for a or the combined response.

Preferably at least one of the elements, or each such element, is provided as one or more of:.

Preferably the response of one or each element is at least one (or a combination) of an isolation or an absorption or a dampening or a reduction of the force(s) or movement(s) imparted to at least the first region from being transferred to at least one other region of the patient interface during use by a user.

Preferably the element is a pre-formed so as to be deformed or displaced in a preferential geometry or dimension.

Preferably the element facilitates a preferential bend or flexure or twist or torsion or a preferential or predetermined pivot or stretch or compression of a material(s) or a component(s) forming the body of the interface.

Preferably such force(s) or movement(s) are resultant from a user of the interface changing their facial geometry to which the interface is retained or located or positioned, or such as by a user pulling or applying a force or movement on or to the interface or an associated headgear thereof, or a breathing circuit or other componentry of the interface applying a force or movement, such as by weighing down upon, a portion of the interface or a headgear associated thereof.

Preferably the applied forces or movement between the nasal prong(s) and body of the patient interface, or between the body of the patient interface and the nasal prong is resultant from changes in user facial geometry, such as during speech, eating, sleeping or other facial distortions between relaxed and exaggerated conditions.

Preferably the at least one element, or at least one of the elements, is located in a bridge region of a nasal cannula patient interface, , to facilitate movement of the bridge region in response to a force or movement or both (in addition, may be such as substantially adjacent the septum region of a user).

Preferably the interface comprises a plurality of elements utilised on their own or in combination with other elements to provide for the response.

Preferably the at least one element is a hinged portion located or positioned as a bridge between a left body portion and a right body portion, each of the body portions together forming the body of an interface to be located upon a user's face, such a hinged portion providing for a preferential region of deformation in response to at least a first region of the body or a portion of the body, experiencing a force or movement (or both) resulting from a change in the facial geometry of the user.

Preferably the patient interface is substantially conformed or conformable to the geometry of a user's face, such that the element responds to the force or movement (or both) to substantially maintain the interface in a preferred therapy delivery configuration for a user.

In a further aspect, the present disclosure may broadly consist in a patient interface, such as a nasal cannula, comprising: a pair of respective left and right body portions, each body portion to be located, in-use upon a face of a user, each of the body portions being separate from each other, at least one, and preferably both, of the body portions including a nasal prong to be inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose, and a bar extending from a connection point with the left body portion to a connection point with the right body portion, the bar comprising a substantially elastically deformable region, wherein a displacement of one or both of the left and/or right body portions when in-use is transmittable to the bar via the connection point, the substantially elastically deformable region being deformable as a reactive response to the displacement.

Preferably the substantially elastically deformable region of the bar comprises a substantially flexible section.

Preferably the substantially elastically deformable region of the bar is deformable to substantially absorb the displacement.

Preferably the substantially elastically deformable region of the bar reduces transmission of a displacement by one of the body portions to the other of the body portions.

Preferably the connection point of the bar to a body portion is via an anchor.

Preferably the anchor is a barbed projection to be received by a region of the body portion located substantially distal to the respective prong.

Preferably the barbed projection and the prong are in fluid communication.

Preferably the elastically deformable region is substantially aligned with the or both prongs in at least one plane.

Preferably each connection point of the bar is in fluid communication with the prong of the respective body portion and is configured to couple a gas flow path of a breathing circuit.

Preferably a facial pad may be associated with each body portion, the facial pad being contoured to engage a region of the user's face.

In a further aspect, the present disclosure may broadly consist in a patient interface, such as a nasal cannula, comprising: a pair of respective left and right body portions, to be located, in-use upon a face of a user, and a bridge portion extending between each of the left and right body portions, a nasal prong extending from one, or each, of the inner-more ends of the respective left and/or right body portions, or extending from a region of one or both of the respective body portions substantially adjacent to the inner-more ends, the nasal prong to be inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose, the bridge portion allowing movement of the respective body portions with the inner-more ends of the body portions being brought toward each another, yet resisting movement of the respective body portions with the inner-more ends being moved away from each other.

Preferably a displacement of the position of one or both of the left and/or right body portions, when the patient interface is in-situ upon a user's face, is transmitted to the bridge in a manner so as to minimise movement of the prong or prongs in relation to the user's nare(s).

Preferably the bridge portion extends and connects inner-more ends of the respective body portions.

Preferably the bridge portion is a material that, in a direction extending between the respective inner-more ends of the body portions, is able to undergo a compression and resists or withstands a tension applied thereto.

Preferably the direction extending between the respective inner-more ends of the body portions is a longitudinal direction extending along the respective body portions.

Preferably the bridge portion comprises a textile material.

Preferably the bridge portion is axially expandable/stretchable but resilient to resist movement of the respective body portions with the inner-more ends being moved away from each other.

Preferably a length of the bridge portion between a connection point on the left body portion and a connection point on the right body portion is larger than a distance between the nasal prongs.

Preferably the bridge portion comprises a flexible polymeric material.

In a further aspect, the present disclosure may broadly consist in a patient interface, such as a nasal cannula, comprising: a pair of respective left and right body portions, to be located, in-use upon a face of a user, a bridge portion extending between each of the left and right body portions, and a nasal prong extending from one, or each, of the inner-more ends of the respective left and/or right body portions, or extending from a region of one or both of the respective body portions substantially adjacent to the inner-more ends, the nasal prong to be inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose, wherein one, and preferably both, of the respective body portions include a user facial contacting surface oriented relative to the respective nasal prong such that, when in situ, a torsional force applied to the left and/or right body portions substantially retains the nasal prong(s) in, or in a position to direct a flow of gas into, the nare(s) of the user's nose.

Preferably rotation of the body portion, and preferably rotation of both body portions, towards a user's face maximises a contact surface area between the facial contacting surface(s) and the face of the user and locates the nasal prong(s) into, or in the position for directing the flow of gases into, the nare(s) of the user's nose.

Preferably the bridge section is of a relatively smaller diameter than the left and right body portions.

Preferably each body portion comprises a channel fluidly connected to the respective nasal prong at one end and open for fluidly coupling a gas flow path of a breathing circuit at an opposing end.

Preferably at least one, and preferably each, of the left and right body portions includes an axially twisted facial contacting surface moveable between a relaxed position and a torsioned position in which a surface area for locating adjacent the user's face is increased.

Preferably the facial contacting surface is axially twisted along a length of the body portion from an inner end of the body portion to an outer end of the body portion.

Preferably the facial contacting surface extends helically along the length of the body portion.

Preferably the facial contacting surface, in the relaxed position, faces away from a direction of extension of the nasal prong(s) at the distal end, and in the torsioned position, faces in the direction of extension of the nasal prong(s) and is substantially planar along a substantial length of the body portion.

Preferably the nasal prong or the nasal prongs are angled relative to the respective left and right body portions to exert torsion on the body portion upon insertion of the nasal prong(s) into the nare(s) of the user's nose.

Preferably the facial contacting surface of the respective left and/or right body portion is contoured to engage the user's facial cheek.

In a further aspect, the present disclosure may broadly consist in a patient interface, such as a nasal cannula, comprising: a pair of respective left and right body portions, to be located, in-use upon a face of a user, and a bridge portion extending between each of the left and right body portions, a nasal prong extending from one, or each, of the inner-more ends of the respective left and/or right body portions, or extending from a region of one or both of the respective body portions substantially adjacent to the inner-more ends, the nasal prong to be inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose, and a series of discrete and separate facial contacting surface(s) movable relative to each other to respond to force(s) or movement(s), or both, experienced by facial contacting surface(s) and at least partially alleviate the transfer of such force(s) and/or movement(s) to the nasal prong(s).

In a further aspect, the present disclosure may broadly consist in a patient interface, such as a nasal cannula, comprising: a pair of respective left and right body portions, each body portion to be located, in-use upon a face of a user, and a bridge portion extending between the left and right body portions, and a nasal prong extending from one, or each, of the inner-more ends of the respective left and/or right body portions, or extending from a region of one or both of the respective body portions substantially adjacent to the inner-more ends, the nasal prong to be inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose, wherein the cannula includes at least one hinged region pivotable relative to another region of the cannula about at least a pair of substantially orthogonal axes, or along a pair of substantially orthogonal planes, or both, to respond to force(s) or movement(s), or both, experienced by the other region and at least partially alleviate the transfer of such force(s) and/or movement(s) to the nasal prong(s).

Preferably at least one hinged region is pivotable about three substantially orthogonal axes, or along three substantially orthogonal planes, or both.

Preferably the bridge comprises a bridge hinge adjacent the nasal prong or between the pair of nasal prongs.

Preferably the bridge hinge is predisposed to have an acute curvature.

Preferably the bridge hinge is predisposed to bend inward toward the user, and downward away from the nare(s) in situ.

Preferably the bridge further comprises a second hinge on one side of the bridge hinge, or a pair of opposed second hinges on either side of the bridge hinge and adjacent the nasal prong or nasal prongs.

Preferably the second hinge or each hinge of the pair of second hinges is predisposed to have an acute curvature.

Preferably the second hinge, or each hinge of the pair of second hinges is predisposed to bend upwardly towards the nare(s) of the user and outwardly away from the user in situ.

Preferably the bridge comprises a third hinge adjacent the left or the right body portion, or a pair of third hinges disposed adjacent the respective left and right body portions.

Preferably the third hinge or each of the pair of third hinges is predisposed to have an acute curvature.

Preferably the third hinge or each of the pair of third hinges is being predisposed to bend downward away from the nare(s) and outward away from the user in situ.

Preferably one end of the bridge portion extends substantially orthogonally from the third hinge, or either end of the bridge portion extends substantially orthogonally from either one of the pair of third hinges and inwardly towards the facial cheek(s) of the user in situ.

Preferably each body portion comprises a facial pad contoured to engage a region of the user's face.

Preferably either end of the bridge portion extends along at least a portion of the facial pad.

Preferably the bridge portion is substantially hollow at least at either end of the bridge portion to transport a flow of gases there through.

Preferably either end of the bridge portion is configured to couple a gas flow path of a breathing circuit.

Preferably the nasal prong, or each nasal prong, extends from, and is fluidly coupled to, a respective end of the bridge portion.

Preferably the bridge portion comprises an annular cross section along at least a substantially portion of the length of the bridge portion.

Preferably the bridge further comprises a fourth hinge adjacent the third hinge, or a pair of fourth hinges adjacent the respective pair of third hinges.

Preferably the fourth hinge or each hinge of the pair of fourth hinges is predisposed to have an acute curvature.

Preferably the fourth hinge, or each hinge of the pair of fourth hinges is predisposed to bend downwardly away from the nare(s) of the user and inwardly toward the facial cheek(s) of the user in situ.

Preferably each body portion comprises a facial pad contoured to engage upon a region of the user's face.

In a further aspect, the present disclosure may broadly consist in a nasal interface configured to stabilize prongs on a patient's face when forces are exerted on the interface, the nasal interface comprising: an elongate body having an overall curvature that generally corresponds to a patient's facial profile, the body configured to be coupled to a gases flow source and comprising at least one lumen extending at least partially through the body; a pair of prongs extending from the body and in fluid communication with the at least one lumen; and one or more hinges, at least one hinge disposed between the pair of prongs that is predisposed to bend in a predefined direction.

Preferably further comprising one or more facial pads configured to rest on a patient's face.

Preferably the at least one hinge disposed between the pair of prongs has a curvature that is generally inverted from the overall curvature of the elongate body.

Preferably the at least one hinge disposed between the pair of prongs is configured to bend inward towards the patient's face.

Preferably the nasal interface has a generally gullwing shape.

Preferably nasal interface has a wavy shape.

Preferably the nasal interface has a curved space frame-like support structure.

Preferably the nasal interface bends in more than one dimension.

Preferably the one or more hinges comprises a notch.

Preferably the one or more hinges comprises a variable cross-sectional area.

Preferably the one or more hinges comprises a variable thickness.

Preferably the one or more hinges comprises two or more materials with different flexibilities.

Preferably the one or more hinges comprises an elastic hinge that is configured to be pre-stressed before application to a patient.

Preferably the one or more hinges comprises a barrel and pin.

Preferably the one or more hinges comprises a ball and socket.

In a further aspect, the present disclosure may broadly consist in a nasal interface comprising: an elongate body comprising at least one lumen extending at least partially through the body, the body configured to be coupled to a gases flow source; one or more prongs extending from the body and in fluid communication with the at least one lumen; and one or more hinges that are predisposed to bend in predefined directions; wherein the one or more hinges are configured to stabilize a position of the one or more prongs on a patient's face when forces are exerted on the nasal interface.

Preferably at least one of the one or more hinges is located adjacent to or between the one or more prongs.

Preferably at least one of the one or more hinges is configured to bend inward towards the patient's face.

Preferably at least one of the one or more hinges is configured to bend downward.

Preferably the nasal interface has a wavy shape.

Preferably the nasal interface comprises two separate sides that are coupled by an over-strap bridge.

In a further aspect, the present disclosure may broadly consist in a nasal interface comprising: an elongate body comprising at least one lumen extending at least partially through the body, the body configured to be coupled to a gases flow source; and one or more prongs coupled to the body and in fluid communication with the at least one lumen; wherein the elongate body has a shape that generally corresponds to an anatomical contour of a patient's or a group of patients' facial profile.

Preferably the group of patients is one of premature babies, neonates, infant, paediatrics or adults.

Preferably the tubular body is initially malleable.

Preferably the shape of the tubular body is set through a hardening process.

The term "comprising" as used in this specification means "consisting at least in part of". When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner.

The term "gullwing" as used in this specification means a shape that comprising of two crests (or crest-like regions) and a trough (or trough-like region) located between such crests, or two troughs (or trough-like regions) and a crest (or crest-like region) located between such troughs, when viewed either as a top or bottom view of the patient interface (for example when the sequence of respective crests or troughs are drawn as a line diagram). Such crests or troughs may transition between each other in a relatively arcuate or curved manner. Optionally, such crests or troughs may be shaped or curved to substantially match or assimilate to facial contours or profile of a typical user's face.

The term "wavy" as used in this specification means a shape that comprises of a plurality of crests (or crest-like regions) and troughs (or trough-like regions), and comprising of at least one trough (or trough-like region) or of at least one crest (or crest-like region) disposed between respectively a pair of crests (or crest-like regions) or at least one trough (or trough-like region) disposed between respectively a pair of crests (or crest-like regions), when viewed from when viewed either as a top or bottom view of the patient interface (for example when the sequence of respective crests or troughs are drawn as a line diagram). Such crests or troughs may transition between each other in a relatively arcuate or curved manner. Optionally, such crests or troughs may be shaped or curved to substantially match or assimilate to facial contours or profile of a typical user's face.

The term "space frame" as used in this specification means a structure that provides for a substantially hollow scaffolding or supporting structure upon or to which a gas delivery line or conduit may be connected or otherwise attached or supported for delivery a gas to a user or a gas outlet of a patient interface (e.g. a nasal prong or pair of nasal prongs).

Where reference is made to a "pre-form", such a pre-formed element means an element that is manufactured or moulded or constructed or assembled so as to provide for a shape or configuration capable of providing for a deformed or displaceable response in a preferential geometry.

Where reference is made to a "preferential geometry", this means a predetermined or preferred plane (or planes) or axis (or axes) of hinging or bending or deforming or displacement.

Where reference is made to a "de-coupling", this means that there is at least a partial isolation or dampening or absorption (or some other mode), preferably a mechanical mode but not limited to this mode, in which forces or movements (or both) experienced or applied to a first region or part of the interface are at least minimised from being entirely transferred to another region or part of the interface.

This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which <FIG> illustrate an embodiment of a patient interface according to this invention:.

The foregoing description of the technology includes preferred forms thereof.

It is desirable to provide for a patient interface in a manner that conforms to a user's changing facial geometry or which is configured in a manner to maintain a stable position upon the user or to at least help improve the maintenance of stability when external forces are applied to such a patient interface.

In achieving one or both of these outcomes, or yet other outcomes, the provision of alternative patient interfaces with improved stability and/or performance on the face of the user would be useful.

In one aspect, this disclosure relates to a patient interface, such as a nasal cannula, comprising a body to be positioned upon a user (preferably such as a user's face). The body including at least one (and preferably a pair of) nasal prong(s), the or each nasal prong including a lumen capable of being fluidly connected thereto for fluid communication with a supply of breathable gas. The, or each, nasal prong to be in a configuration either inserted into, or to direct a flow of gas toward, a nare or the nares of the user's nose. The body includes at least one element responsive to force(s) or movement(s), or both, experienced by at least a first region of the patient interface from being transferred to at least one other region of the patient interface.

In relation to such an invention, reference is made to the accompanying drawings which detail specific embodiments thereof. Details of the specific embodiments are provided in the various sections below.

Before the specific embodiment details, the following description relates to the invention as detailed above. For example, such an interface can include an element which facilitates the reduction in transfer of a force or movement, or both, as applied to at least a first region of the interface from being transferred to at least another region of the interface. It will be appreciated such an element may be the hinged portion as detailed below with reference to the figures and specific embodiment descriptions. It will also be appreciated that a first region may be any part, component, zone or area of a patient interface, which may be exposed to a force or movement (or both) imparted by a user directly, or whether imposed by a component of a breathing circuit or headgear or other componentry associated with a patient interface and breathing circuits providing for a supply of breathable gas, or other items that could be found in the user's vicinity e.g. pacifier, blanket, cushion, toys etc..

The element of this invention is designed to respond in a manner to localise the force or the movement, or both, experienced by the at least first region.

It may also be that the element is able to respond in a way so as to minimise or prevent transfer of the force or the movement, or both, from the at least first region to at least one other region of the patient interface. The outcome or result from this response is the ability for such an interface to be more stable when installed or positioned on a user.

In this context, it will be appreciated a patient interface may be particularly those such as nasal cannula.

Extension of this invention may also have applicability to yet other interfaces, such as to masks (whether full face, oral, nasal, nasal pillow or oro-nasal) or other derivatives or variants of these.

The element (or elements) incorporated into the interface preferably respond in a manner to maintain the at least one (and preferably the pair of) nasal prong(s) in the configuration of insertion in a nare or nares of the user's nose, or in the configuration of directing a flow of gas toward a nare or nares of the user's nose. For example, another desired outcome is that the response is such that the at least one (or preferably the pair of) nasal prong(s) maintain a stable position within or adjacent to the nares of a user's nose to which the prong(s) is directed.

The element's response operates to go at least some way toward preventing or minimising transfer of force or movement from the at least first region of the interface to at least one other region of the interface. Accordingly, a more stable interface can be provisioned for use by a user. In providing for a more generally stable interface, an improvement in user comfort may be achieved. An improvement in the delivery of therapy to a user may also be achieved. Both such achievements may together result in a more user friendly interface or device.

Advantageously, this invention enables an interface having the capability or inclusion of elements which are responsive in a manner such that the interface maintains an operational position upon the user.

In addition, the force or movement, or both, experienced by at least a first region of the interface are either, or both, of i) an applied force(s) or a movement(s) between the nasal prong(s) and body of the patient interface, or ii) an applied force(s) or a movement(s) between the body of the patient interface and the nasal prong(s). The element responds to such forces or movements in a way so as to at least substantially ameliorate the transfer of forces or movements to other parts of the interface, or to at least do so in a manner so as to retain the interface on the user in an operational or comfortable configuration, or to at least mitigate the potential for the interface becoming uncomfortable or moving out of a therapeutic operational configuration for the user.

In certain embodiments, the element is a deformable member or a member that can be deformed in response to the force or movement (or both).

Predetermined or preferential modes of deformation by the element in response to the applied force or movement, or both, being experienced by at least a first region of the interface may be provided. For example, the element may be deformable in certain preferential geometries, such as about at least one axis or at least one plane, or both. It will be appreciated the deformation may be in a plurality of axes or planes or geometries, such deformation being in a preferential direction so as to provide for the response by the element to the applied force or movement (or both). It will also be appreciated such deformation may be one or a combination of at least a compression or a tension or a torsion or bending or other flexion of the element or a plurality of elements.

In respect of the element, the response may also be one or a combination of any one of a changing shape, or a changing of position, or a changing of configuration.

Various embodiments of such an element include, but are not specifically limited to one or more of the following, each of which may be used in combination with each other, or connected by members or other sections or components so as to provide for a plurality of elements which in combination provide for a desired response to ameliorate the transfer of a force or movement to the interface from at least a first region:.

hinges, pivots, articulated joints or articulately connected portions of the body or portions associated with the body, swivels, ball-and-socket type joints, pin-in-barrel type joints,.

materials which are relatively less flexible than other portions of the interface, materials which are relatively more flexible than other portions of the interface, materials of characteristics which change upon application of a force or movement, such as by increasing their resistance to the applied force or movement (or both), or by reducing their resistance to the applied force or movement (or both), or materials which are elastically deformable in response to the applied force or movement (or both), or materials which are preferentially deformable in particular or predetermined geometries and yet which may optionally resistant to deformation in other particular or predetermined geometries,.

The element can be configured to provide or to operate or to work in response to the force or movement or both to prevent or minimise or at least reduce the overall force of movement experienced by the at least first region of the interface from being transferred to at least one other region of the interface.

The element may be a structure or a mechanism or a material characteristic or any combinations of structure, mechanism and material characteristic, incorporated into the interface, or may be a region of the interface incorporating one or a plurality of such elements in, or upon the interface.

In certain forms, the element may have predetermined or preferential modes of deformation in response to the applied force or movement. For example, the element may be deformable about at least one axis or at least one plane, or about a preferential first geometry, or may be deformable by one or a combination of a compression or a tension or torsion or bending or other such flexion.

One or a plurality of elements can be utilised and incorporated into the interface, such elements may operate or work or provide for the response on their own or may do so in combination with each other. Certain combined response from a plurality of elements may have advantages in that some elements may provide for a response to ameliorate the transfer of a force or movement from one region of the interface to other regions, and yet other elements respond in a different manner. For example, different elements may have different modes of response or be connected to each other, operatively or not, or to other parts of the interface in desired manners. Such a combined response or use of elements can preferably allow for an overall improvement in the comfort or stability of the interface during use on a user.

An element as incorporated in an interface of this invention may desirably be provided as one or more of:.

The response of an element may therefore be at least one (or a combination) of an isolation or an absorption or a dampening or a reduction or a de-coupling of the force(s) or movement(s) imparted to at least the first region from being transferred to at least one other region of the patient interface during use by a user.

Provision may be made so as to include an element which has a pre-form so as to be deformed or displaced in a preferential geometry or dimension as its response to the force or movement (or both).

For example, the element can facilitate a preferential bend or flexure or twist or torsion or a preferential or predetermined pivot or stretch or compression of a material(s) or a component(s) forming the body of the interface.

The element may be a region of different material characteristic or structure, such a as spongy material or a material capable of withstanding a tension, but not a compression, or a compression but not a tension, or allowing of a stretch or extension (or a compression) of a material or components of the element in certain geometries yet resistive to stretching or tension in other geometries.

Various configurations of elements, such as ball-and-socket joints may be provided which are provided between different regions of an interface, such as for example between an off-centre body portion of a nasal cannula interface (e.g. a left or a right body portion, or both) and a central portion or region (e.g. a bridge portion which may be in the septum area of a user), such an element facilitating a response which reducing the transfer of a force or movement to other parts of the interface, thereby helping to improve user interface comfort and continued maintenance of therapy delivery.

Yet other variations include sections of an interface in which the element is to be located, for example as a hinged portion or a pivot or swivel jointed portion or region so as to allow for the element to preferentially bend or accommodate an applied force or movement.

The force(s) or movement(s) can be any which are applied to or which the interface may experience. Typically, certain forces or movements may be resultant from a user of the interface changing their facial geometry to which the interface is retained or located or positioned, or such as by a user pulling or applying a force or movement on or to the interface or an associated headgear thereof, or a breathing circuit or other componentry of the interface applying a force or movement, such as by weighing down upon, a portion of the interface or a headgear associated thereof.

Changes in interface user facial geometry, such as during speech, eating, sleeping or other facial distortions and between relaxed and exaggerated conditions, can also contribute to forces or movements being applied or imparted to a region or regions of an interface.

The elements of this invention are beneficially configured to assist in reducing the likelihood of such forces or movements from impacting on comfort or delivery of therapy to a user of the interface.

In various examples, where the patient interface is a nasal cannula, the applied forces or movement between the nasal prong(s) and body of the patient interface, or between the body of the patient interface and the nasal prong may encourage the problem of prong flicking (where the nasal prongs of an interface move about with the nares of a users nose or may even be removed entirely from the nares). Nasal prongs moving about in the nares may irritate a user, whilst removal or dislodgment of the prongs from the nares impacts on the preferred delivery of therapy to the user. Systems or methods to assist in avoiding prong flicking are advantageous.

In one particular embodiment, at least one element or at least one of the elements, is located in the bridge region of a nasal cannula patient interface, such as substantially adjacent the septum region of a user.

In other embodiments, the interface can comprise of a plurality of elements utilised on their own or in combination with other elements to provide for the response.

In still further embodiments, the at least one element can be a hinged portion located or positioned as a bridge between a left body portion and a right body portion, each of the body portions together forming the body of an interface to be located upon a user's face, such a hinged portion providing for a preferential region of deformation in response to at least a first region of the body or a portion of the body, experiencing a force or movement (or both) resulting from a change in the facial geometry of the user.

In all embodiments discussed here, there may be an additional but optional configuration of the interface to be generally conformed or conformable or be anatomically shaped for a users face or part of the body to which the interface is to be located. In this manner, a patient interface that is substantially conformed or conformable to the geometry of a user's face may allow for the element to responds to the force or movement (or both) to substantially maintain the interface in a preferred therapy delivery configuration for a user.

Provided below is yet further specific embodiments according to this invention and as illustrated with reference to the accompanying drawings.

An aspect of at least one of the embodiments disclosed herein includes the realization that with at least nasal interfaces, the stability of the nasal interface on the face is important, as movement of the nasal interface can cause severe irritation to the nares or cause the prongs to displace out of the patient's nares, which can lead to prevention or interruption of therapy.

The current methods of retaining nasal interfaces to a patient's face have disadvantages that can cause the prongs to displace out of the nares or irritate the sensitive area of the nares. These undesired consequences can occur from a variety of reasons, including but not limited to, incorrect application, incorrect sizing, patient position, facial movements and abnormal facial geometries.

In the case of tubing that is routed around the patient's ears, the tubing can fall off the ears and cause the prongs to dislodge from the nares. The tubing can also be displaced when the patient lies on the side of their head, causing the prongs to dislodge from the nares or rub against the sides of the nares. Furthermore, the use of a strap or an elastic band is disadvantageously prone to sliding of the nasal interface relative to the patient's head especially when the patient turns his/her head on a pillow, causing the prongs to dislodge from the nares or cause severe irritation. Other external forces can also cause the nasal prongs to dislodge from or irritate the nares, such as the supply tube getting caught on other objects or the patient pulling on the tubing.

Previously, adhesive medical tape has been used to retain the nasal interface in place. However, the fixation of the interface to the patient's face has been found to cause issues with the retention of the prongs in the patient's nares, especially for infants and neonates. When the patient's face is squeezed from lying on the side, current nasal interfaces tend to bend at the bridge of the nasal interface in a direction away from the face. The bending of the interface causes the prongs to displace out of the patient's nares, or become crushed against the sides of the patient's nose so as to cause at least a partial blockage of the gases being delivered to the patient.

It will be appreciated that in some embodiments the patient interfaces as described herein may be utilised in conjunction with a headgear system for locating or securing such a patient interface upon a user's face, yet such patient interfaces remain capable of being able to respond to forces or movements (or both) when used in such an arrangement.

In yet other embodiments, it will be appreciated that a headgear arrangement or configuration may operate to take some of the load the patient interface may experience due to forces or movements (or both) experienced by the interface, whilst the interface operates to take some of the load also.

Thus, in accordance with at least one of the embodiments disclosed herein, a nasal interface can be used that prevents or substantially reduces the likelihood of prongs displacing out of the patient's nares or irritating the nares as caused by facial movements or external forces.

A nasal interface can be configured to stabilize prongs on a patient's face when forces are exerted on the interface. The nasal interface can include an elongate body having an overall curvature that generally corresponds to a patient's facial profile, the body being configured to be coupled to a gases flow source and having at least one lumen extending at least partially through the body. The nasal interface can have prongs extending from the body and in fluid communication with the at least one lumen. The nasal interface can have one or more hinges, at least one hinge can be disposed between the pair of prongs, or between the nares when in use, that is predisposed to bend in a predefined direction.

The nasal interface can include one or more facial pads configured to rest on a patient's face. In some embodiments, the at least one hinge disposed between the pair of prongs can have a curvature that is generally inverted from the overall curvature of the elongate body. The at least one hinge disposed between the pair of prongs can be configured to bend inward towards the patient's face. The nasal interface can bend in more than one dimension.

The nasal interface can have a generally gullwing shape. In some embodiments, the nasal interface can have a wavy shape. In some embodiments, the nasal interface can have a curved space frame-like support structure.

The one or more hinges can include a notch. The one or more hinges can include a variable cross-sectional area. The one or more hinges can include a variable thickness. The one or more hinges can include two or more materials with different flexibilities. The one or more hinges can include an elastic hinge that is configured to be pre-stressed before application to a patient. The one or more hinges can include a barrel and pin. The one or more hinges can include a ball and socket.

In some embodiments, a nasal interface can include an elongate body having at least one lumen extending at least partially through the body, the body being configured to be coupled to a gases flow source. One or more prongs can extend from the body and be in fluid communication with the at least one lumen. The nasal interface can include one or more hinges that are predisposed to bend in predefined directions, wherein the one or more hinges are configured to stabilize a position of the one or more prongs on a patient's face when forces are exerted on the nasal interface.

The nasal interface can include one or more facial pads configured to rest on a patient's face. At least one of the one or more hinges can be located adjacent to or between the one or more prongs, or in addition, along one of the facial pads. At least one of the one or more hinges can be configured to bend inward towards the patient's face. At least one of the one or more hinges can be configured to bend downward. The nasal interface can bend in more than one dimension.

The nasal interface can have a generally gullwing shape. In some embodiments, the nasal interface can have a wavy shape.

The nasal interface can have a curved space frame-like support structure.

In some embodiments, the nasal interface can have two separate sides that are coupled by an over-strap bridge.

In some embodiments, a nasal interface can include an elongate body having at least one lumen extending at least partially through the body, the body configured to be coupled to a gases flow source. One or more prongs can be coupled to the body and be in fluid communication with the at least one lumen. The elongate body can have a shape that generally corresponds to an anatomical contour of a patient's or a group of patients' facial profile.

The group of patients can be one of premature babies, neonates, infant, paediatrics, teens or adults. In some embodiments, the tubular body can be initially malleable. The shape of the tubular body can be set through a hardening process.

It has been discovered that the behaviour of a nasal interface under loading can be controlled to improve its stability performance. In this disclosure, nasal interfaces that prevent or substantially reduce the likelihood of prongs displacing out of the patient's nares or irritating the patient's nares as a result of facial movements or external forces are described.

Human facial geometry varies greatly due to a large range of factors. These factors include but are not limited to gender, ethnicity, age and medical conditions. Incorrect sizing and geometry of nasal interfaces can adversely affect the stability and usability of the nasal interfaces. Other causes that can affect stability include, but are not limited to, incorrect application, patient position, patient crying and abnormal facial geometries.

Furthermore, when a patient speaks, eats, cries or has their facial features distorted or exaggerated in any way, it can affect the stability of an interface on the patient's face. More prolonged changes to facial features can arise from aspects such as patient position while sleeping for example. Long term changes in geometry can occur from patient growth and injury recovery.

When supporting items on a patients face, any external forces can affect device stability as well. In the case of a transverse nasal interface, external forces can arise from a range of sources such as patients pulling on the interface, breathing circuit weight being transmitted to the interface, head strap retention forces or any connected tubing getting caught on other equipment.

Nasal interfaces <NUM> traditionally have a manifold <NUM> with prongs <NUM> extending from the manifold <NUM>, as shown in <FIG>. A bridge <NUM> is connected between the prongs <NUM> and may allow for fluid communication between the prongs <NUM>. This design can be unstable on the patient's face, which can lead to dislodgement of the nasal prongs from the patient's nares and adverse effects on therapy to the patient. Oftentimes, the dislodgement of the prongs from the nares is a result of the interface's mechanical reaction to a particular force applied to it.

The behaviour of a nasal interface under loading, such as from a patient speaking or lying on the side of their face, can be affected by a variety or combination of different interface features, such as interface geometry and material properties. For example, <FIG> shows a traditional nasal interface <NUM> with forces <NUM> exerted to the sides of the interface. Forces <NUM> may be exerted to the interface, for instance, when the patient is lying on the side of their face or when the patient's face is squeezed. A traditional nasal interface <NUM> in a relaxed state is shown by dotted lines in <FIG> also shows the nasal interface in a squeezed state when forces <NUM> are exerted on the interface. With continued reference to <FIG>, when the forces <NUM> are exerted on the sides of the nasal interface, most traditional interfaces naturally tend to bend upward in the figure or away from the patient in the middle near the prongs <NUM> because of the geometric design and material properties of the interface. The bending of the interface displaces the position of the prongs <NUM> such that they flick out of the patient's nares or rub against the sides of the nares, irritating the sensitive skin of the nares. <FIG> illustrates the prongs <NUM> displaced from their normal relaxed positions by a distance of Y.

As described herein, nasal interface stability can be improved by utilizing one or more of anatomically formed shapes and geometrically dynamic forms in the interface design. These designs can at least partially mechanically react to facial movements or external forces to help maintain nasal prong stability.

With a traditional interface's straight design, additional retention such as adhesive tape is often required to secure the interface to a patient's facial geometry. <FIG> is a bottom view illustrating a traditional interface <NUM> on a patient's face <NUM>. As shown in this figure, retention forces F may be required to secure the interface <NUM> on the patient's face <NUM>. However, the retention forces F can change the shape of the interface <NUM> and the elastic properties of the nasal interface can produce restorative forces opposing the retention force. These restorative forces can cause the retention method to detach and cause the prongs to apply pressure on the inside of the nares, causing sores. The unnatural bent shape of the nasal interface can also cause the prongs to not fit properly and cause sores as well.

The following describes components and properties of example nasal interfaces in greater detail. Sub-headings are used, such as "Anatomically Formed Interfaces" and "Dynamic Interfaces. " These sub-headings are not, and should not be construed as limiting. For example, aspects of one or more embodiments described under the Anatomically Formed Interfaces sub-heading can also apply to one or more embodiments described under the Dynamic Interfaces subheading, and vice versa.

Anatomically formed interfaces <NUM> are shaped to fit the facial profile of a given population, as illustrated in <FIG>. These interfaces <NUM> incorporate shapes which are anatomically curved to fit the three-dimensional facial contours of a particular demographic; e.g., premature babies, neonates, infant, paediatrics and adult. The anatomically curved interface's <NUM> shape can significantly increase the stability of an interface on a patient's face <NUM> and can reduce the incidences of prong displacement out of the patient's nares.

Whilst not limiting, the illustrated embodiments may have particular applicability to neonates. For example, such interfaces may be especially suitable for use with neonates due to the increased facial distortion occurring in neonates, due to the small size of their head/face and any movements may be accentuated by their relatively small size.

The anatomically formed interface <NUM> conforms to a patient's facial profile while in a natural, relaxed shape. The interface does not need to be bent by retention forces to stabilize the interface on the patient's face <NUM> and thus no restorative forces are produced. Even when adhesive tape is used to fix the anatomically formed interface to the patient's face, no restorative forces are present because the tape does not bend the interface. The prongs remain in the patient's nose in a natural, unstressed position and the likelihood of dislodgement or injury to the patient's nares is reduced compared to traditional interfaces. Another advantage of the anatomically formed interface <NUM> is the reduced need for adhesive tapes to retain the interface on the patient's face <NUM>, reducing the likelihood of skin irritation or injury. The anatomically formed interface <NUM> has increased stability compared to a traditional interface and there is less need to tape the interface to the patient's face to maintain stability.

The anatomically formed interface <NUM> can be manufactured using plastic moulding methods to form a predetermined curved shape which has been identified to fit a given demographic of patient. For example an underdeveloped premature baby has a different facial profile to that of a fully developed term baby so for each of these demographics a common facial profile can be identified which compliments a high percentile of that population. A plurality of different sizes and shapes of interfaces can be produced to fit a wide variety of facial profiles.

In some embodiments, the anatomically formed interface can be modified by the patient or caregiver after manufacture. The anatomically formed interface can be flexible and formable into a custom shape to fit the patient's face. For example, the interface can be at least partially made of a malleable material such as medical putty or flexible plastic. The patient or caregiver can shape the malleable interface to generally correspond to the contours of the patients face and provide a stable fit with the patient's face.

In other examples, the anatomically formed interface can have a malleable frame extending through the interface that can be bent to generally match the contours of the patient's face and provide a structural shape to the interface. In order for the interface to maintain its shape after shaping, a post annealing process can be applied to the malleable frame in some embodiments.

Other types of formable interface materials can include one or more of silicone, rubber (synthetic or natural), thermoplastic and thermosetting polymers. The composite materials can be fabricated by co-moulding or overmoulding. These materials can be initially malleable so that they can be shaped to the patient's face shape, and then become rigid after a period of time or through an active hardening process, such as a UV treatment or heat treatment.

A dynamic interface incorporates one or more hinges along the device that reacts to facial movements, both natural and forced, and external forces exerted on the interface. The hinges can minimise the effects of the facial movements and external forces on the fitment of the interface on the patient's face, particularly on the placement of the prongs in the patient's nares. As used herein, hinges refers generally to portions on the interface that are configured to bend in one or more directions. The hinges can be configured to bend in a predefined direction or directions, and in some embodiments the hinges can be restricted from bending in certain directions.

<FIG> illustrate an example of a relaxed facial shape of an infant and <FIG> illustrates a schematic of the geometric shape of a dynamic interface <NUM> on a relaxed face. <FIG> is a front view of an infant's face and <FIG> is a bottom view of the infant's face. <FIG> is a bottom view of a dynamic interface. The dynamic interface <NUM> can have one or more hinges <NUM>. Preferably, the dynamic interface has a center hinge <NUM> disposed between the prongs <NUM>. As can be noticed by comparing <FIG>, the plurality of hinges <NUM> on the interface allows the interface <NUM> to conform to the general contours of the patient's face.

<FIG> illustrate a front view and a bottom view, respectively, of an example of a stressed or squeezed facial shape of an infant. <FIG> illustrates a bottom view schematic of the geometric shape of a dynamic interface <NUM> on a squeezed face. The squeezed face approximates, for example, the contortion of the face when patients lie on the side of their faces. As illustrated in <FIG>, the hinges <NUM> help conform the interface <NUM> to the shape of the contorted face and maintain the position of the prongs <NUM> in the nares of the patient. The dynamic interface <NUM> is particularly helpful in the case of infants who tend to exhibit exaggerated cheek movement.

Each hinge <NUM> can be configured to react to an applied force in a predetermined fashion and different hinges can react differently depending on their position on the interface. For example, a hinge <NUM> located in the region between the prongs <NUM> may bend downward toward the lips and/or inward toward the face to form a concave shape when viewed from the front, while the hinges <NUM> adjacent the cheeks of the patient may bend outward to form a convex shape around the cheeks. The hinge <NUM> can resist movement outwards normal to the face and minimise the movement of the prongs <NUM> out of the nares due to forces applied laterally on the device. In some situations, the bending of hinge <NUM> can be limited by the patient's anatomy. For example, the inward bending of hinge <NUM> can be limited by the philtrum of the patient, which can beneficially limit the displacement of the prongs <NUM>. The forces applied to the interface may act on the other hinges (e.g., hinges <NUM> adjacent the cheeks) once the hinge <NUM> reaches its limit. Combinations of hinge types and hinge locations can allow the designer to control how an interface will react in a variety of situations. A hinge may be designed to allow for <NUM>, <NUM> or <NUM> degrees of motion in any predefined direction depending on its desired function. Advantageously, an inherently stable interface can be developed that keeps the prongs in the patients nares under various loading conditions.

<FIG> illustrate an example of how a dynamic interface <NUM> can react to external forces <NUM>. As shown in <FIG>, an extension <NUM> can be coupled to the dynamic interface <NUM> with a hinge <NUM>. The extension <NUM> can be a part of the dynamic interface <NUM> that connects to external devices, or the extension <NUM> can be a part of an external device that connects to the dynamic interface <NUM>. For example, the extension <NUM> can be a part of the dynamic interface <NUM> and connectable to a tube, or the extension <NUM> can be a part of a tube that connects to the interface <NUM>. The hinge <NUM> can be located at the connection point of the extension <NUM> and the interface <NUM>. With reference to <FIG> any external forces <NUM>, such as pushing or pulling on the tube, will be dampened by the reaction of the hinge <NUM> and reduce the forces being translated onto the dynamic interface <NUM>. The external forces <NUM> can be at least partially isolated from affecting the positioning of the prongs <NUM> in the patient's nares. Preferably, another hinge <NUM> is located on the extension <NUM> for increased dampening ability of the extension <NUM>. In some embodiments, further additional hinges can be disposed on the extension <NUM> for even more dampening ability.

The hinges and their positions on the interface can be customized to work effectively with the particular retention method of the interface. For example, with continued reference to <FIG>, if the interface is configured to be secured to the cheeks with tape or some similar retention method, there can be one or more hinges located between the cheek section and the prongs to account for facial movements. Similarly, with reference to <FIG>, if a head strap is connected to the extension <NUM>, at least one hinge can be located between the head strap and interface to account for external forces.

An example of a dynamic nasal interface <NUM> is illustrated in <FIG>. The gullwing shaped dynamic interface <NUM> can have an overall curvature that generally corresponds to a patient's facial profile. The dynamic interface <NUM> can include one or more nasal prongs <NUM>, a bridge <NUM> extending between the prongs <NUM> that is configured to be along a patient's upper lip beneath the nose in use, a pair of wings or facial pads <NUM> and integral tubing <NUM>, all spaced generally symmetrically about the sagittal plane. The dynamic interface <NUM> is formed as an integral or unitary component with the tubing <NUM> in fluid communication with the prongs <NUM>. The open end of each integrated tubing <NUM> is configured to receive a suitable breathing tube that is connected to a gases supply. The breathing tube may be adhered or otherwise coupled (or connected) to the interface tubing <NUM>. Preferably, the tubing <NUM> includes two separate sides that have independent flow paths. However in some embodiments, the two sides can be in fluid communication, such as through a tube that extends across the bridge to connect the two sides of tubing.

The facial pads <NUM> are anatomically shaped with a size, shape and curvature that reflects the facial geometry of the intended patient. The anatomical shape of the facial pads <NUM> gives the interface a positive engagement with a patient's face at a predetermined position where the contour of the facial pads <NUM> matches the patient's facial contour. The pre-shaped facial pads <NUM> compliment the nasal prongs <NUM> by improving the accuracy and speed with which the prongs <NUM> can be placed and retained within a patient's nares.

Pre-shaping or contouring the facial pads <NUM> to the patient's facial features reduces the pressure applied to the patient's face by any retention mechanism (adhesive tape, headgear or other means). This reduces the likelihood of pressure sores upon the user. The positive engagement promoted by the anatomical shape of the facial pads <NUM> increases the stability of the interface <NUM> and the prong <NUM> and therefore improves comfort and efficacy of the treatment being administered. In some embodiments, the facial pads <NUM> can be wider at the outer portions and taper to be narrower toward the middle. Further examples of nasal interfaces may be as described in International Patent Application Publication No. <CIT>.

With continued reference to <FIG>, the bridge <NUM> of the nasal interface <NUM> can have a bridge hinge <NUM> that is configured to bend inward toward the patient. As best illustrated in the <FIG>, the bridge <NUM> has an inverted curvature compared to the rest of the nasal interface such that the interface has a gullwing-like shape. The bridge hinge <NUM> is curved toward the rear of the interface <NUM> such that the bridge <NUM> is convex shaped when viewed from the front. The curvature of the bridge <NUM> predisposes the hinge <NUM> to bend inward toward the patient, as opposed to outward as in the case of traditional nasal interfaces.

For example, <FIG> illustrates a nasal interface <NUM>, for example having a generally gullwing type shape, with forces <NUM> exerted to the sides of the interface. Forces <NUM> may be exerted to the interface, for instance, when the patient is lying on the side of their face or when the patient's face is squeezed. The nasal interface <NUM> in a relaxed state is shown by dotted lines in <FIG> also shows the nasal interface in a stressed state when forces <NUM> are exerted on the interface. When the forces <NUM> are exerted on the sides of the nasal interface, the bridge <NUM> is inclined to bend inward at the bridge hinge <NUM>, as shown by the central arrow in <FIG>. The inward bending of the bridge <NUM> displaces the prongs <NUM> inward closer to the patient, as opposed to outward away from the patient, where the prongs <NUM> may flick out of the nares, as is the case in traditional nasal interfaces. As discussed above, the bending of the bridge hinge <NUM> can be limited by the patient's anatomy. For example, the inward bending of the bridge hinge <NUM> can be limited by the philtrum of the patient, which can beneficially limit the displacement of the prongs <NUM>. The nasal interface design helps reduce the risk of the prongs <NUM> flicking out of the patient's nares or rubbing against the sides of the nares.

The displacement distance of the prongs <NUM> can typically be less than compared to traditional nasal interfaces. <FIG> illustrates the prongs <NUM> displaced from their normal relaxed positions by a displacement of Z, which is in the opposite direction and typically a smaller distance compared to the displacement of Y shown in <FIG> for a traditional nasal interface. The nasal cannula hinges in at least three locations, the bridge hinge <NUM> and outer hinges <NUM>, <NUM> on either sides of the prongs; whereas traditional nasal interfaces bend mainly at a single position at the bridge. The additional hinges of the nasal interface help stabilize the positions of the prongs <NUM> when the cannula is under stress and reduce the displacement distance, helping to keep the prongs in the nares of the patient and reduce the irritation of the nares by the prongs.

Another example of a dynamic nasal interface <NUM> is illustrated in <FIG>. The dynamic interface <NUM>, for example having a generally wavy type shape, includes one or more nasal prongs <NUM>, a bridge <NUM> extending between the prongs <NUM>, a pair of wings or facial pads <NUM> and tubing <NUM> coupled to the facial pads <NUM>, all spaced generally symmetrically about the sagittal plane. The dynamic interface <NUM> can be formed as an integral or unitary component with the tubing <NUM> in fluid communication with the prongs <NUM>. The open end of each integrated tubing <NUM> is configured to receive a suitable breathing tube that is connected to a gases supply. The breathing tube may be adhered or otherwise coupled (or connected) to the interface tubing <NUM>. Preferably, the tubing <NUM> includes two separate sides that have independent flow paths. However in some embodiments, the two sides can be in fluid communication, such as through a tube that extends across the bridge to connect the two sides of tubing.

The facial pads <NUM> are shaped to generally match the anatomical shape of the facial geometry of an intended patient. As illustrated in <FIG>, the facial pads <NUM> can have a wavy shape that generally matches the shape of a patient's profile, as illustrated for example in <FIG>. The facial pads <NUM> can have an outer concave portion <NUM> configured to lie over the protruding cheeks of the patient and an inner convex portion <NUM> configured to lie over the creases between the cheeks and upper lip. The bridge <NUM> can have a concave shape to accommodate the bump of the upper lip and philtrum. The tubing <NUM> can follow the contours of the nasal interface <NUM>.

The anatomical shape of the facial pads <NUM> gives the interface a positive engagement with a patient's face at a predetermined position where the contour of the facial pads <NUM> matches the patient's facial contour. The pre-shaped facial pads <NUM> compliment the nasal prongs <NUM> by improving the accuracy and speed with which the prongs <NUM> can be placed and retained within a patient's nares.

<FIG> illustrates a front view of the nasal interface <NUM>. The facial pads <NUM> can be wider at the outer portions and taper to be narrower toward the middle. The bridge <NUM> can be integral with the facial pads <NUM> and in some embodiments connects the two facial pads <NUM>. In some embodiments, the bridge <NUM> can be curved downward and have a hinge <NUM>. The hinge <NUM> can be predisposed to bend downward such that when the nasal interface <NUM> experiences forces from facial movements or external forces, the bridge <NUM> can bend downward. The downward bending can help stabilize the prongs <NUM> and minimize movement of the prongs <NUM> in the sagittal plane (i.e., front/back) and coronal plane (i.e., up/down). The downward bending of the bridge <NUM> displaces the prongs <NUM> closer together, but does not displace the prongs <NUM> outward away from the nares, as is the case in traditional nasal interfaces. The nasal interface design helps reduce the risk of the prongs <NUM> flicking out of the patient's nares or rubbing against the sides of the nares.

<FIG> illustrate another non-limiting example of a dynamic nasal interface <NUM>. The dynamic interface <NUM> includes one or more nasal prongs <NUM>, a curved space-frame support structure <NUM> with a bridge <NUM> extending between the prongs <NUM>, a pair of wings or facial pads <NUM> and tubing <NUM> coupled to the facial pads <NUM>, all spaced generally symmetrically about the sagittal plane. The dynamic interface <NUM> can be formed as an integral or unitary component with the tubing <NUM> in fluid communication with the prongs <NUM>. The open end of each integrated tubing <NUM> is configured to receive a suitable breathing tube that is connected to a gases supply. The breathing tube may be adhered or otherwise coupled to the interface tubing <NUM>. Preferably, the tubing <NUM> includes two separate sides that have independent flow paths. However in some embodiments, the two sides can be in fluid communication, such as through a tube that extends across the bridge to connect the two sides of tubing.

The facial pads <NUM> can be shaped to generally match the anatomical shape of the facial geometry of an intended patient. As illustrated in <FIG>, the facial pads <NUM> can be disposed toward the outer portions of the dynamic interface <NUM> and curved to match the shape of a patient's cheeks. In some embodiments, the facial pads can extend further toward the middle of the dynamic interface and/or can be connected as a continuous pad extending across the entire dynamic interface. The facial pads <NUM> can have a concave portion <NUM> configured to lie over the protruding cheeks of the patient.

With continued reference to <FIG>, the nasal prongs <NUM> and tubing <NUM> can be at least partially supported by the support structure <NUM>. The support structure <NUM> can be coupled to the facial pads <NUM> and include a bridge <NUM> between the prongs <NUM>. The dynamic interface <NUM> with the space frame-like support structure <NUM> helps stabilize the interface from three-dimensional changes in the patient's facial geometry and helps maintain the prongs <NUM> in the nares of the patient. In some embodiments, the support structure <NUM> can be hollow and in fluid communication with the prongs <NUM> such that the prongs <NUM> are in fluid communication with each other. In other embodiments, the prongs <NUM> may be separate and not fluidly connected with each other, at least not through the support structure <NUM>. In these embodiments, the support structure <NUM> can be solid, hollow or filled with material such as for example foam or a malleable wire frame.

In some embodiments, the bridge <NUM> can be curved downward and have a hinge <NUM>. The hinge <NUM> can be predisposed to bend downward such that when the dynamic interface <NUM> experiences forces from facial movements or external forces, the bridge <NUM> can bend downward, as illustrated in <FIG> illustrate squeezing of the dynamic interface <NUM> on a patient's face to simulate extreme facial deformations or external forces. The downward bending can help stabilize the prongs <NUM> and minimize movement of the prongs <NUM> in the sagittal plane (i.e., front/back) and coronal plane (i.e., up/down). The downward bending of the bridge <NUM> displaces the prongs <NUM> closer together, but does not displace the prongs <NUM> outward away from the nares, as is the case in traditional nasal interfaces. The dynamic interface <NUM> design may help reduce the risk of the prongs <NUM> flicking out of the patient's nares or rubbing against the sides of the nares.

With continued reference to <FIG>, the support structure <NUM> can further include one or more inner hinges <NUM> and/or one or more outer hinges <NUM>, such that the support structure <NUM> has a zig-zag shape. The inner hinges <NUM> can be predisposed to bend upward such that when the dynamic interface <NUM> experiences forces, the inner hinges <NUM> can bend upward, as illustrated in <FIG>. The outer hinges <NUM> can be predisposed to bend downward such that when the dynamic interface <NUM> experiences forces, the outer hinges <NUM> can bend downward, as illustrated in <FIG>. When the dynamic interface <NUM> experiences facial movements or external forces, the hinges <NUM>, <NUM>, <NUM> can work in conjunction to deform and at least partially absorb the forces in order to stabilize the nasal prongs <NUM> and help prevent the prongs <NUM> from flicking out of the patient's nares or rubbing against the sides of the nares.

<FIG> illustrate another non-limiting example of a dynamic nasal interface <NUM> that has hinges that bend in more than one dimension. The multi-dimensional dynamic interface <NUM> can include one or more nasal prongs <NUM>, a pair of wings or facial pads <NUM> and tubing <NUM> coupled to the facial pads <NUM>, all spaced generally symmetrically about the sagittal plane. The tubing <NUM> can be configured to receive a suitable breathing tube that is connected to a gases supply. The breathing tube may be adhered or otherwise coupled to the interface tubing <NUM>.

The facial pads <NUM> can be shaped to generally match the anatomical shape of the facial geometry of an intended patient. As illustrated in <FIG>, the facial pads <NUM> can be disposed toward the outer portions of the dynamic interface <NUM> and curved to match the shape of a patient's cheeks. In some embodiments, the facial pads can extend further toward the middle of the dynamic interface and/or can be connected as a continuous pad extending across the entire dynamic interface. The facial pads <NUM> can have a concave portion configured to lie over the protruding cheeks of the patient.

In some embodiments, the dynamic nasal interface <NUM> includes a structural member <NUM> that defines a shape and bending characteristic of the dynamic nasal interface <NUM>, as illustrated for example in <FIG>. The structural member <NUM> can be overmoulded or otherwise attached to the dynamic nasal interface <NUM>, such as with adhesives, sonic welding, clamps, or the like. The structural member <NUM> illustrated in <FIG> includes a bridge hinge <NUM> configured to be positioned between the prongs <NUM> and predisposed to bend downward. The illustrated structural member <NUM> also includes inner hinges <NUM> that are predisposed to bend upward, and outer hinges <NUM> that are predisposed to bend inward toward the patient. The bending hinges can occupy the grooves or cavities that naturally occur in the anatomy of most patients' faces, such as the crease between the cheeks and edges of the nose <NUM>, and the space in the philtrum <NUM>, as illustrated in <FIG>. In some embodiments, the multi-directional dynamic interface <NUM> can be pre-stressed before being attached to the patient's face, as explained below, to help the hinges bend in a predetermined direction and stabilize the nasal prongs.

<FIG> illustrates a front view of a multi-directional dynamic interface <NUM> on a patient's face. <FIG> illustrates a front view of the multi-directional dynamic interface <NUM> as stresses are applied to the patient's face. When stresses such as squeezing forces are exerted on patient's face, the multi-directional dynamic interface <NUM> bends in a predefined manner. The bridge hinge <NUM> can bend downward and inward toward the space in the philtrum <NUM>, as illustrated in <FIG>. The inner hinges <NUM> can bend upward. The outer hinges <NUM> bend inward toward the patient into the crease between the cheeks and nose <NUM>, as illustrated in <FIG>. The bending of some of the hinges can be limited by the patient's anatomy. For example, the inward bending of bridge hinge <NUM> can be limited by the philtrum <NUM> of the patient, which may beneficially limit the displacement of the prongs <NUM>. The bending of the outer hinges <NUM> can be limited by the creases <NUM>, which may also beneficially limit the displacement of the prongs <NUM>. When the multi-directional dynamic interface <NUM> experiences facial movements or external forces, the hinges <NUM>, <NUM>, <NUM> can work in conjunction to deform in multiple dimensions to at least partially absorb the forces in order to stabilize the nasal prongs <NUM> and help prevent the prongs <NUM> from flicking out of the patient's nares or rubbing against the sides of the nares.

<FIG> illustrate another non-limiting example of a dynamic nasal interface <NUM>. The dynamic nasal interface <NUM> can have an overall curvature that generally corresponds to a patient's facial profile and can include two separate sides, each with a nasal prong <NUM>, facial pad <NUM> and tubing <NUM> coupled to the facial pads <NUM>. The tubing <NUM> can be in fluid communication with the prongs <NUM>. An over-strap bridge <NUM> can extend between and connect the two sides of the over-strap dynamic interface <NUM>. The open end of the tubing <NUM> is configured to receive a suitable breathing tube that is connected to a gases supply. The breathing tube may be adhered or otherwise coupled to the interface tubing <NUM>.

The facial pads <NUM> can be shaped to generally match the anatomical shape of the facial geometry of an intended patient. As illustrated in the top view of <FIG>, the facial pads <NUM> can be disposed toward the outer portions of the dynamic interface <NUM> and can be curved to match the shape of a patient's cheeks. The facial pads <NUM> can have a concave portion configured to lie over the protruding cheeks of the patient.

With continued reference to <FIG>, an over-strap bridge <NUM> can extend between the two sides of the over-strap dynamic interface <NUM>. The over-strap bridge <NUM> can be coupled to the interface tubing <NUM>, as illustrated in the figures, or to the facial pads <NUM> and can be attached anywhere along each side of the dynamic interface <NUM>. In the illustrated example, the over-strap bridge <NUM> is connected generally toward the middle of the interface tubing <NUM>. In other embodiments, the over-strap bridge <NUM> can be connected toward the prongs <NUM> or toward the outer edges of the dynamic interface <NUM>. The connection <NUM> between the over-strap bridge <NUM> and the sides of the dynamic interface <NUM> can be a rigid connection. In some embodiments, the connection <NUM> can be adjustable or flexible, such as with a hinge.

The over-strap bridge <NUM> can be made of a resilient material that can be stretched or adjusted to conform to a patient's facial shape and size. For example, the over-strap bridge <NUM> can be adjusted to enable the prongs <NUM> to be spaced according to an individual patient's nasal anatomy, providing a wide range of patient sizes that can be accommodated by a particular over-strap dynamic interface <NUM>. The over-strap bridge <NUM> has a bridge hinge <NUM> that is predisposed to bend inward toward the patient such that when the dynamic interface <NUM> experiences forces from facial movements or external forces, the over-strap bridge <NUM> bends inward.

As illustrated in the <FIG>, the bridge hinge <NUM> has an inverted curvature compared to the rest of the nasal interface. The bridge hinge <NUM> is curved toward the rear of the dynamic interface <NUM> such that the bridge hinge <NUM> is convex shaped when viewed from the front. The inward bending can help stabilize the prongs <NUM> and minimize movement of the prongs <NUM> in the sagittal plane (i.e., front/back) and coronal plane (i.e., up/down). The inward bending of the bridge hinge <NUM> can displace the prongs <NUM> closer together, but does not displace the prongs <NUM> outward away from the nares, as is the case in traditional nasal interfaces. The dynamic interface <NUM> design may help reduce the risk of the prongs <NUM> flicking out of the patient's nares or rubbing against the sides of the nares.

In some embodiments, the bridge <NUM> with bridge hinge <NUM> can be configured to be preloaded during fitting such that the over-strap dynamic interface <NUM> can absorb forces when the patient's face moves or when external forces are exerted on the dynamic interface <NUM>.

The dynamic interfaces described above can at least partially made of a resilient material that can return to its original shape after being deformed by the patient's facial movements or external forces. These materials are also preferably compliant so that they conform to the patients' facial geometries. The dynamic interface materials can include silicone, rubber (synthetic or natural), thermoplastic and thermosetting polymers. The composite materials can be fabricated by co-moulding or overmoulding.

A variety of hinge types can be used in the dynamic interfaces. The hinges can bend in a predictable, limited number of directions to define the mechanical behaviour of the dynamic interface. The following paragraphs describe a number of hinge types and how they can be implemented. The described hinges are not an exhaustive list. The hinge types include, but are not limited to: notches, cross-sectional area, variable thickness, composite, elastic hinge, barrel & pin, and ball & socket.

<FIG> illustrates a nasal interface <NUM> with a hinge <NUM> disposed at the bridge <NUM> between the prongs <NUM>. The hinge <NUM> can be solid and can include one or more notches <NUM>. In the embodiment illustrated in <FIG>, the hinge <NUM> includes three notches <NUM> disposed on a side <NUM> of the hinge <NUM> facing away from the direction of the desired bend. The notches <NUM> help the hinge <NUM> bend in the illustrated direction of moment M because the notches <NUM> help relieve tensile stress on the side <NUM> as the notches <NUM> open up. The hinge <NUM> is predisposed to bending in direction M.

<FIG> illustrates another embodiment of a nasal interface <NUM> having a bridge <NUM> between the prongs <NUM>. The bridge <NUM> is hollow and allows gases to flow through such that the prongs <NUM> are in fluid communication with each other through the bridge <NUM>. A bridge <NUM> can have a notch and act as a hinge <NUM>. A number of non-limiting examples of notches are provided in <FIG> illustrates a triangular notch <NUM>, <FIG> illustrates a channel notch <NUM>, and <FIG> illustrates a trapezoidal shaped notch <NUM>. The notch designs can be altered to permit different amounts of bending at the hinge and a designer can choose the proper type of notch design to achieve the desired amount of bending.

A hinge can be designed into a structure through variations in its cross-sectional profile. Under an applied load a structure's cross-sectional area can predispose it to deflect in a certain direction. For example, the structure can be a bridge located between the prongs of the nasal interface. A loading force F is assumed in the transverse direction as illustrated for hinge <NUM> in <FIG>, simulating the exaggerated facial movements or external forces discussed above. The illustrated triangular cross-sectional profile promotes bending downwards towards the mouth in the example of the bridge. The downward bending reduces the effect of the load F on the prongs' position in the nares, as discussed above.

<FIG> illustrates a triangular cross-sectional profile of hinge <NUM> having a neutral axis <NUM> of bending, which is located closer to the tensile region <NUM> of the structure while in its bent state. Predisposing a structure to bend in a desired direction can be achieved through making the cross-sectional area at the tensile region <NUM> (i.e., the region preferred to come into tension) greater than the cross-sectional area at the compression region <NUM> (i.e., the region preferred to come under compression). Because materials tend to have a compressive elastic modulus greater than a tensile elastic modulus, when a loading force F is applied to the hinge <NUM>, it takes less force to compress the compression regions <NUM> and stretch the tensile region <NUM>, as opposed to stretching the compression region <NUM> and compressing the tensile region <NUM>. Accordingly, the hinge <NUM> can bend in a predictable downward direction.

<FIG> illustrate an example of a design feature, such as cutouts, which allows for reduced compressive stress. <FIG> illustrates loading forces F on a nasal interface <NUM> in the transverse direction. The nasal interface <NUM> has one or more prongs <NUM> and a hinge <NUM> disposed between the prongs <NUM>. <FIG> is a close-up cross-section of the hinge region. As shown in the figure, the hinge <NUM> includes a tensile region <NUM> and compression region <NUM>. As discussed above, a structure can be predisposed to bend in a desired direction by making the cross-sectional area of the tensile region <NUM> greater than the cross-sectional area at the compression region <NUM>. In the example illustrated in <FIG>, the compression region <NUM> is comprised of flanges <NUM> and a hollow channel <NUM> between the flanges <NUM>. The hollow channel <NUM> gives the compression region <NUM> a smaller cross-sectional area than the tensile region <NUM> and the hinge <NUM> can bend in a predictable downward direction.

<FIG> illustrate an example of a hinge <NUM> that has a variable thickness. Similar to as shown in <FIG>, loading forces F may be exerted on the nasal interface <NUM> in the transverse direction. With reference to <FIG>, the nasal interface <NUM> has one or more prongs <NUM> and a hinge <NUM> disposed between the prongs <NUM>. The hinge <NUM> can be thinner in a particular direction compared to other directions such that the hinge <NUM> is predisposed to bending in the direction of thinnest material. For example, in the illustrated embodiment, the hinge <NUM> is thinner in the direction of prong extension, i.e., the up/down direction in the view of <FIG> is a close-up cross-section of the hinge region showing an elliptical cross-section. The hinge <NUM> will bend in a predictable downward direction because the hinge is thinnest in the up/down direction.

<FIG> illustrate a hinge <NUM> that includes two materials with different properties, such as a rigid and flexible material overlaid together, that function to bend in a predetermined direction. <FIG> illustrates an embodiment having a flexible portion <NUM> and a rigid portion <NUM> in an unbent state. When forces are exerted onto the flexible portion <NUM>, bending is predisposed in the direction opposing the rigid portion <NUM>, as illustrated in <FIG>. The rigid portion <NUM> prevents the flexible portion <NUM> from bending toward the rigid portion <NUM>, and the flexible portion <NUM> can only bend in one or more predisposed direction. The two material types can be secured using overmoulding techniques or the like to bond the materials at a central location <NUM> of the hinge <NUM>. In some embodiments, the two material types can be removably secured in one or more locations of the hinge. The outer portions of the flexible material <NUM> are preferably allowed unconstrained movement.

An elastic hinge can be utilised to aid securement of an interface onto a patient's face. An elastic hinge can store elastic energy by pre-stressing the nasal interface before application to a patient. Once the nasal interface is on the patient, the stored elastic energy in the elastic hinges acts upon the patient's face to aid securement. An elastic hinge can have a relaxed state where substantially no elastic energy is stored in the hinge, and a pre-stressed state where some external forces have bent the hinge allowing it to store some elastic energy.

For example, a patient's face can be in a relaxed state, such as shown in <FIG>, or in a stressed state, such as shown in <FIG>. The nasal interface can be formed such that the relaxed state of the interface generally corresponds to the stressed profile of the patient's face. <FIG> illustrates an example of an elastic hinge nasal interface <NUM> in a relaxed state. As illustrated in <FIG>, the nasal interface <NUM> in a relaxed state can generally correspond to the stressed profile of a patient's face and in this configuration the nasal interface <NUM> may exert no forces on the patient's stressed face.

When fitting an elastic hinge nasal interface <NUM> on a patient's face, a user can pre-stress the nasal interface by, for example, stretching the nasal interface as illustrated in <FIG>. When the pre-stressed nasal interface is placed on a patient's relaxed state face, the curves in the nasal interface serve as elastic hinges <NUM>, as shown by cross-hatching on <FIG>. When the patient's face is stressed, the elastic hinge nasal interface <NUM> is predisposed to bend back to its relaxed state shown in <FIG>. The elastic hinge nasal interface <NUM> can follow the patient's facial profile as the face goes from a relaxed profile to a stressed profile, which can stabilize the nasal prongs and help prevent the prongs from flicking out of the patient's nares or rubbing against the sides of the nares.

The nasal interface can be attached to the patient's face through a plurality of different types of retention methods, such as for example adhesives and straps. Preferably, the retention method of the nasal interface on the patient's face has a strength that can at least withstand the pre-stress energy stored in the elastic hinges.

The elastic hinge nasal interface can be made of a resilient material that can store energy when stretched from its relaxed state. Some non-limiting examples of materials include rubber, plastics, composites and steel.

Another hinge design that can be used with the dynamic interfaces includes a pin and barrel design. <FIG> illustrates a dynamic interface <NUM> with a pin and barrel hinge design disposed at the bridge <NUM> between the nasal prongs <NUM>. When a patient's facial profile changes, for example due to external forces or facial movement, the angle of the pin and barrel hinge can adjust to accommodate the facial movement or external forces. The adjustment by the pin and barrel hinge helps stabilize the prongs in the patient's nares.

<FIG> illustrates an example of a pin and barrel hinge <NUM>. A first side of the hinge can have a pin <NUM> attached or integrally formed on first side. A second side can have a barrel <NUM> (e.g., through hole) attached or integrally formed on the second side. The pin <NUM> can be inserted into the barrel <NUM> and retained by a functional coupler. The pin <NUM> can rotate relative to the barrel <NUM> to form the hinge <NUM>.

<FIG> illustrate a pin and barrel hinge <NUM> with directional movement. The pin and barrel hinge <NUM> includes a stop <NUM> that prevents the hinge from bending in a certain direction, so that the hinge <NUM> is predisposed to bend in a desired direction, for example downward away from the patient's nares. The directional hinge designs can be strategically disposed in particular portions of a nasal interface to control the way the interface bends when a force is applied to the interface. Although the directional hinge design is illustrated herein in combination with a pin and barrel design, the directional hinge design can also be used with other types of hinges, such as those described herein.

<FIG> illustrates an example of a nasal interface <NUM> having a ball and socket hinge <NUM> between the nasal prongs <NUM>. A first side of the hinge <NUM> can have a ball <NUM> attached or integrally formed on first side. A second side can have a barrel <NUM> (e.g., cavity) attached or integrally formed on the second side. The ball <NUM> can move and rotate inside the barrel <NUM> to provide three degrees of movement about the centre of the hinge. When a patient's facial profile changes, for example due to external forces or facial movement, the three degrees of movement of the ball and socket hinge <NUM> can adjust to accommodate the facial movement or external forces, and help to stabilize the prongs <NUM> in the patient's nares.

With reference to the embodiment shown in <FIG>, a patient interface <NUM>, such as a nasal cannula, has a pair of respective left <NUM> and right <NUM> body portions, each body portion to be located, in-use upon a face of a user, each of the body portions being separate from each other. At least one, and preferably both, of the body portions include a nasal prong <NUM>, <NUM> to be inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose. A bar <NUM> extends from a connection point 2109a with the left body portion to a connection point 2109b with the right body portion. The bar comprises a substantially elastically deformable region <NUM>.

A displacement of one or both of the left and/or right body portions <NUM>, <NUM> when in-situ is transmitted to the bar <NUM> via the connection point, the substantially elastically deformable region <NUM> being deformable as a reactive response to the displacement.

The substantially elastically deformable region <NUM> of the bar <NUM> is a substantially flexible section that is deformable to substantially absorb the displacement. The substantially elastically deformable region <NUM> of the bar reduces transmission of a displacement by one of the body portions to the other of the body portions.

The connection point 2109a, 2109b of the bar <NUM> to a body portion is via an anchor, in the form of a barbed projection <NUM>. The barbed projection <NUM> is received by a region <NUM> of the body portion located substantially distal to the respective prong such that the barbed projection and the prong are in fluid communication.

The elastically deformable region <NUM> is substantially aligned with the or both prongs <NUM>, <NUM> in at least one plane. Each connection point 3209a, 2109b of the bar <NUM> is in fluid communication with the prong of the respective body portion and is configured to couple a gas flow path of a breathing circuit. The interface also has a facial pad <NUM>, <NUM> associated with each body portion. Each facial pad <NUM>, <NUM> is contoured to engage a region of the user's face.

With reference to the embodiments shown in <FIG>, a patient interface <NUM>/<NUM>, such as a nasal cannula, has a pair of respective left <NUM>/<NUM> and right <NUM>/<NUM> body portions, to be located, in-use upon a face of a user. A bridge <NUM> portion extends between each of the left and right body portions. A nasal prong <NUM>/<NUM>, <NUM>/<NUM> extends from one, or each, of the inner-more ends of the respective left and/or right body portions, or extends from a region of one or both of the respective body portions substantially adjacent to the inner-more ends. The nasal prongs <NUM>/<NUM>, <NUM>/<NUM> are to be inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose.

The bridge portion <NUM>/<NUM> allows movement of the respective body portions <NUM>/<NUM>, <NUM>/<NUM> with the inner-more ends of the body portions being brought toward each another, yet resists movement of the respective body portions with the inner-more ends being moved away from each other. A displacement of the position of one or both of the left and/or right body portions, when the patient interface is in-situ upon a user's face, is transmitted to the bridge portion <NUM>/<NUM> in a manner so as to minimise movement of the prong or prongs in relation to the user's nare(s).

With reference to the embodiment shown in <FIG>, the bridge portion <NUM> extends and connects inner-more ends of the respective body portions <NUM>, <NUM>. The bridge portion 2409is a material that, in a direction extending between the respective inner-more ends of the body portions, is able to undergo a compression and resists or withstands a tension applied thereto. The direction extending between the respective inner-more ends of the body portions is a longitudinal direction extending along the respective body portions. The bridge portion preferably comprises a textile material, which may be a woven, knitted, or non-woven textile material.

With reference to the embodiments shown in <FIG>, the bridge portion <NUM> is axially expandable/stretchable, but resilient to resist movement of the respective body portions with the inner-more ends being moved away from each other. A length of the bridge portion between a connection point 2509a, 2509b on the left body portion and a connection point on the right body portion is larger than a distance between the nasal prongs <NUM>, <NUM>. The bridge portion <NUM> preferably comprises a flexible polymeric material.

With reference to the embodiments shown in <FIG>, the patient interface <NUM>/<NUM>, such as a nasal cannula, has a pair of respective left <NUM>/<NUM> and right <NUM>/<NUM> body portions, to be located, in-use upon a face of a user. A bridge portion <NUM>, <NUM> extends between each of the left and right body portions. A nasal prong <NUM>/<NUM>, <NUM>/<NUM> extends from one, or each, of the inner-more ends of the respective left and/or right body portions, or extends from a region of one or both of the respective body portions substantially adjacent to the inner-more ends. The nasal prong <NUM>/<NUM>, <NUM>/<NUM> is inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose. One, and preferably both, of the respective body portions include a user facial contacts surface <NUM>/<NUM>, <NUM>/<NUM> oriented relative to the respective nasal prong such that, when in situ, a torsional force applied to the left and/or right body portions substantially retains the nasal prong(s) in, or in a position to direct a flow of gas into, the nare(s) of the user's nose.

Rotation of the body portion, and preferably rotation of both body portions, towards a user's face maximises a contact surface area between the facial contacting surface(s) and the face of the user and locates the nasal prong(s) into, or in the position for directing the flow of gases into, the nare(s) of the user's nose.

The bridge section <NUM>/<NUM> is of a relatively smaller diameter than the left and right body portions. Each body portion comprises a channel fluidly connected to the respective nasal prong at one end and open for fluidly coupling a gas flow path of a breathing circuit at an opposing end.

With reference to the embodiment shown in <FIG>, at least one, and preferably each, of the left and right body portions includes an axially twisted facial <NUM>, <NUM> contacting surface moveable between a relaxed position and a torsioned position in which a surface area for locating adjacent the user's face is increased.

The facial contacting surface <NUM>, <NUM> is axially twisted along a length of the body portion from an inner end of the body portion to an outer end of the body portion. The facial contacting surface <NUM>, <NUM> extends helically along the length of the body portion. The facial contacting surface, in the relaxed position, faces away from a direction of extension of the nasal prong(s) at the distal end, and in the torsioned position, faces in the direction of extension of the nasal prong(s) and is substantially planar along a substantial length of the body portion.

With reference to the embodiment shown in <FIG>, the nasal prong(s) <NUM>, <NUM> are angled relative to the respective left and right body portions to exert torsion on the body portion upon insertion of the nasal prong(s) into the nare(s) of the user's nose. The facial contacting surface of the respective left and/or right body portion is contoured to engage the user's facial cheek.

With reference to the embodiment shown in <FIG>, a patient interface, such as a nasal cannula, has a pair of respective left and right body portions, to be located, in-use upon a face of a user. A bridge portion extends between each of the left and right body portions. A nasal prong extends from one, or each, of the inner-more ends of the respective left and/or right body portions, or extends from a region of one or both of the respective body portions substantially adjacent to the inner-more ends. The nasal prongs are inserted into, or to direct a flow of gas into, a nare or the nares of the user's nose. The interface has a series of discrete and separate facial contacting surface(s) movable relative to each other to respond to force(s) or movement(s), or both, experienced by facial contacting surface(s) and at least partially alleviate the transfer of such force(s) and/or movement(s) to the nasal prong(s).

With reference to the embodiment shown in <FIG>, a patient interface <NUM>/<NUM>, such as a nasal cannula, has a pair of respective left <NUM>/<NUM> and right <NUM>/<NUM> body portions, each body portion to be located, in-use upon a face of a user. The patient interface <NUM>/<NUM> also has a bridge portion <NUM>/<NUM> extending between the left and right body portions. A nasal prong extends from one, or each, of the inner-more ends of the respective left and/or right body portions, or extends from a region of one or both of the respective body portions substantially adjacent to the inner-more ends. The nasal prong <NUM>/<NUM>, <NUM>/<NUM> is inserted into, or to directs a flow of gas into, a nare or the nares of the user's nose. The cannula includes at least one hinged region, described in detail blow. The at least one hinged region is pivotable relative to another region of the cannula about at least a pair of substantially orthogonal axes, or along a pair of substantially orthogonal planes, or both, to respond to force(s) or movement(s), or both, experienced by the other region and at least partially alleviate the transfer of such force(s) and/or movement(s) to the nasal prong(s). The at least one hinged region may be pivotable about three substantially orthogonal axes, or along three substantially orthogonal planes, or both.

The bridge <NUM>/<NUM> also comprises a bridge hinge <NUM> adjacent the nasal prong or between the pair of nasal prongs. The bridge hinge <NUM> is predisposed to have an acute curvature. The bridge hinge <NUM> is predisposed to bend inwardly toward the user, and downwardly away from the nare(s) in situ.

The bridge <NUM>/<NUM> further comprises a second hinge on one side of the bridge hinge, or a pair of opposed second hinges <NUM>, <NUM> on either side of the bridge hinge <NUM> and adjacent the nasal prong or nasal prongs. The second hinge or each hinge of the pair of second hinges <NUM>, <NUM> is predisposed to have an acute curvature. The second hinge, or each hinge of the pair of second hinges <NUM>, <NUM> is predisposed to bend upwardly towards the nare(s) of the user and outwardly away from the user in situ.

The bridge comprises a third hinge adjacent the left or the right body portion, or a pair of third hinges <NUM>, <NUM> disposed adjacent the respective left and right body portions. The third hinge or each of the pair of third hinges <NUM>, <NUM> is predisposed to have an acute curvature. The third hinge or each of the pair of third hinges <NUM>, <NUM> is being predisposed to bend downward away from the nare(s) and outward away from the user in situ.

With reference to the embodiment shown in <FIG>, one end of the bridge portion extends substantially orthogonally from the third hinge, or either end <NUM>, <NUM> of the bridge portion extends substantially orthogonally from either one of the pair of third hinges and inwardly towards the facial cheek(s) of the user in situ. Each body portion has a facial pad <NUM>, <NUM> contoured to engage a region of the user's face. Either end of the bridge portion extends along at least a portion of the facial pad.

The bridge portion <NUM> is substantially hollow at least at either end of the bridge portion to transport a flow of gases there through. Either end of the bridge portion is configured to couple a gas flow path of a breathing circuit. The bridge portion <NUM> comprises an annular cross section along at least a substantially portion of the length of the bridge portion.

The nasal prong(s) <NUM>, <NUM> extend(s) from, and is/are fluidly coupled to, a respective end of the bridge portion.

Claim 1:
A nasal interface (<NUM>) comprising:
an elongate body comprising: one or more facial pads or wings (<NUM>) and at least one lumen extending at least partially through the body, the body configured to be coupled to a gases flow source,
wherein the one or more facial pads or wings (<NUM>) are configured to be spaced symmetrically about the sagittal plane of a user in use, and
one or more prongs (<NUM>) coupled to the body and in fluid communication with the at least one lumen,
wherein at least one element (<NUM>, <NUM>) is located adjacent to and outside of the one or more prongs (<NUM>), and characterised in that the element(s) (<NUM>, <NUM>) are pre-formed in a convex shape outward from the user's face in use.