(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`
`(19) World Intellectual Property Organization _
`International Bureau
`
`| D
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`' I|||||||||||||ll|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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`
`
`(43) International Publication Date
`17 January 2008 (17.01.2008)
`
`(51) International Patent Classification:
`A6IM 16/06 (2006.01)
`
`(21) International Application Number:
`PCT/NZ2007/000185
`
`(22) International Filing Date:
`
`13 July 2007 (13.07.2007)
`
`English
`English
`
`(25) Filing Language:
`(26) Publication Language:
`(30) Priority Data:
`548575
`551103
`
`14 July 2006 (14.07.2006)
`6 November 2006 (06.11.2006)
`
`(74)
`
`NZ
`NZ
`
`(71) Applicant (for all designated States except US): FISHER
`& PAYKEL HEALTHCARE LIIVIITED [NZ/NZ]; 15
`Maurice Paykel Place, East Tamaki, Auckland, 0213 (NZ).
`(72) Inventors; and
`(for US only): MCAULEY,
`(75) Inventors/Applicants
`Alastair, Edwin [NZ/NZ]; 58A Ngapuhi Road, Re-
`muera, Auckland, 1050 (NZ). ERSTICH, Evan, Stuart
`[NZ/NZ]; 100 Main Highway, Ellerslie, Auckland, 1051
`(NZ). GLEESON, Oliver [NZ/NZ]; 19A Ropata Avenue,
`
`(31)
`
`(54) Title: BREATHING ASSISTANCE APPARATUS
`
`
`
`WO2008/007985A1|||||||||||||||||||||||||||||||||||||||||I|||||||||||||||||||||||||||||||||||||||||||||||||||||
`
`(10) International Publication Number
`
`WO 2008/007985 A1
`
`Point England, Auckland, 1072 (NZ). FREEMAN, Si-
`mon, Eric [NZ/NZ]; 53 Glenvar Road, Torbay, Auckland,
`0630 (NZ). DAVIES, Neil, Glen [NZ/NZ]; 22A Browns
`Avenue, Pakuranga, Auckland, 2010 (NZ). SCHOEN-
`BERG, Stephen, John [US/NZ]; 4/78 Wajatarua Road,
`Remuera, Auckland, 1050 (NZ). LAW, Kaman [NZ/NZ];
`1616 Dominion Road Extension, Mt Roskill, Auckland,
`1041 (NZ). PRENTICE, Craig, Robert [NZ/NZ]; 95
`Kiwi Esplanade, Mangere, Auckland, 2022 (NZ).
`
`Agents: ADAMS, Matthew, D et al.; A J Park, 6th Floor
`Huddart Parker Building, PO Box 949, Wellington, 6015
`(NZ).
`
`Designated States (unless otherwise indicated, for every
`kind of national protection available): AE, AG, AL, AM,
`AT, AU, AZ, BA, BB, BG, BH, BR, BW, BY, BZ, CA, CH,
`CN, CO, CR, CU, CZ, DE, DK, DM, DO, DZ, EC, EE, EG,
`ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL,
`IN, IS, JP, KE, KG, KM, KN, KP, KR, KZ, LA, LC, LK,
`LR, LS, LT, LU, LY, MA, MD, ME, MG, MK, MN, MW,
`MX, MY, MZ, NA, NG, NI, NO, NZ, OM, PG, PH, PL,
`
`[Continued on next page]
`
`(57) Abstract: Headgear for use with
`a respiratory mask is described. The
`headgear comprises a continuous and
`substantially curved elongate member
`extending in use below a user’s nose
`and at least two headgear straps capable
`of attachment to the ends of the elongate
`member. A mask attachment on the
`
`is disposed to sit
`elongate member
`below or on one of said user’s nose,
`mouth, upper lip and an inlet to the
`mask.
`The attachment
`is capable of
`receiving the mask.
`
`RMD 1023
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`1
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`RMD 1023
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`

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`WO 2008/007985 A1
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`||||||||||||||ll|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
`
`PT, RO, RS, RU, SC, SD, SE, SG, SK, SL, SM, SV, SY,
`TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA,
`ZM, ZW.
`
`PT, RO, SE, SI, SK, TR), OAPI (BF, BJ, CF, CG, CI, CM,
`GA, GN, GQ, GW, ML, MR, NE, SN, TD, TG).
`
`Published!
`(84) Designated States (unless otherwise indicated, for every
`kind of regional protection available): ARIPO (BW, GH, — With i7lT€VVl€lti0Ylfll Search V5170”
`GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM,
`ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM),
`European (AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FT,
`FR, GB, GR, HU, IE, IS, IT, LT, LU, LV, MC, MT, NL, PL,
`
`For two—letter codes and other abbreviations, refer to the "Guid-
`ance Notes on Codes andAbbreviations ” appearing at the begin-
`ning of each regular issue of the PCT Gazette.
`
`2
`
`

`
`WO 2008/007985
`
`PCT/NZ2007/000185
`
`BREATHING ASSISTANCE APPARATUS
`
`BACKGROUND OF THE INVENTION
`
`Technical Field
`
`The present invention relates to apparatus for treating sleep apnoea. More specifically,
`
`the present invention provides a nasal interface for the supply of respiratory gases, but most
`
`particularly positive pressure gases.
`
`Summary of the Prior Art
`ln the art of respiration devices, a variety of respiratory masks which cover the nose
`
`and/or mouth of a human user in order to provide a continuous seal around the nasal and/or
`
`‘oral areas of the face are well known. Masks that provide gas at positive pressure within the
`
`mask for consumption by the user are also well known. The uses for such masks range from
`
`high altitude breathing (i.e., aviation applications) to mining and tire fighting applications, to
`
`various medical diagnostic and therapeutic applications.
`
`Obstructive Sleep Apnoea (0 SA) is a sleep disorder that affects up to at least 5% ofthe
`
`population in which muscles that normally hold the airway open relax and ultimately collapse,
`
`sealing the airway. The sleep pattern of an OSA sufferer is characterised by repeated
`
`sequences of snoring, breathing difficulty, lack of breathing, waking with a start and then
`
`returning to sleep. Often the sufferer is unaware ofthis pattern occurring. Sufferers of OSA
`
`usually experience daytime drowsiness and irritability due to a lack of good continuous sleep.
`
`In an effort to treat OSA sufferers, a technique known as Continuous Positive Airway
`
`Pressure (CPAP) was devised. A CPAP device consists of a gases supply (or blower) with a
`
`conduit connected to supply pressurised gases to a patient, usually through a nasal mask. The
`
`pressurised air supplied to the patient effectively assists the muscles to keep the patient’s
`
`airway open, eliminating the typical OSA sleep pattern.
`
`The procedure for administering CPAP treatment has been well documented in both
`
`the technical and patent literature. Briefly stated, CPAP treatment acts as apneumatic splint of
`
`the airway by the provision of a positive pressure, usually in the range 4 to 20 cm I-I20. The
`
`air is supplied to the airway by a motor driven blower whose outlet passes via an air delivery
`
`hose to a nose, full face, nose and mouth, or oral mask that is sealingly engaged to a patient’s
`face, preferably by means of a harness or other headgear. An exhaust port is usually also
`
`provided in the delivery tube proximate to the mask or on the mask itself. More sophisticated
`
`3
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`_ 2 _
`
`forms ofpositive airway pressure devices, such as bi—level devices and auto-titrating devices,
`
`are described in US Patent No. 5,148,802 ofRespironics, Inc. and US Patent No. 5,245,995 of
`
`Rescare Limited, respectively.
`
`One requisite ofrespiratory masks has been that they provide an effective seal against
`
`the user’s face to prevent leakage of the gas being supplied. Commonly, in prior mask
`
`configurations, a good mask—to-face seal has been attained in many instances only with
`
`considerable discomfort for the user. A common complaint of a user of CPAP therapy is
`
`pressure sores caused by the mask about the nose and face and in particular in the nasal bridge
`
`region of the user. This problem is most crucial in those applications, especially medical
`
`applications, which require the user to wear such a mask continuously for hours or perhaps
`
`even days.
`
`In such situations, the user will not tolerate the mask for long durations and
`
`optimum therapeutic or diagnostic objectives thus will not be achieved, or will be achieved
`
`with great difficulty and considerable user discomfort.
`
`US Patent No. 5,477,852 of Airways Ltd, Inc. discloses a nasal positive airway
`
`pressure device that has a pair of nasal members each having a cannula tip to be inserted into
`
`the nares of the patient. Each carmula is tapered from a substantially circular cross section
`
`outside the patient’s nostril to a substantially oval cross section at the tip inserted into the
`
`nostril. An inflatable cuff surrounds each cannula with the interior space of the cuff
`
`communicating with the lumen ofthe cannula through at least one aperture in the sidewall of
`
`the cannula. The nasal members are connected to one or more flexible hoses that, in turn, are
`
`connected to a source of positive air pressure. In use, positive air pressure is supplied to each
`cannula tip through the air hoses and nasal members. The positive air pressure inflates the l
`
`‘
`
`cuffs to hold the nasal members in place and to effect treatment. The nasal device of US
`
`Patent No. 5,477,852 is attached to headgear that is located about a patient’s head. This
`
`headgear could be considered by many patients as cumbersome and uncomfortable.
`
`Conventional nasal masks used for administrating CPAP treatment are also considered
`
`uncomfortable and cumbersome, and prior art nasal masks can be noisy due to air leaks. These
`
`disadvantages in many cases are a formidable obstacle to patient acceptance ofsuch treatment.
`
`Therefore, a substantial number ofpatients either cannot tolerate treatment or choose to forego
`
`treatment. It is believed a number of such patients might benefit from a nasal positive airway
`
`pressure apparatus that is more convenient to use and comfortable to wear, thereby resulting in
`
`increased treatment compliance.
`
`4
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`

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`_ 3 -
`
`Innomed Technologies,
`
`Inc. manufactures a nasal cannula device called the
`
`NASALAIRETM.
`
`In this device air or oxygen travels down a wide bore conduit to nasal
`
`cannula. The NASALAIRETM creates a physical seal between the nares and itself, and relies
`
`on the absence of leaks around the cannula and the nares to deliver pressure supplied by a
`
`continuous positive airway pressure (CPAP) blower to the airway of the wearer.
`
`US6,l 19,694 ofRespironics Georgia, Inc discloses a nasal mask having a nare seal and
`
`lateral support members to support the mask.
`
`WO2004/073 778 ofResMed Limited discloses a nasal mask including a frame where
`
`headgear is provided with rigid sections that extend to the nasal mask.
`
`W004/0413 41 ofResMed Limited discloses headgear for a patient mask that includes
`
`a sewn on rigid section to the back area of headgear straps to provide rigidity to the straps.
`
`US6,907,882 ofResMed Limited discloses a nasal mask and headgear that is attachable
`
`to the frame of the nasal mask. The headgear straps have rigid sections integral with the
`
`releasable connectors that attach the headgear to the mask.
`
`DISCLOSURE OF THE INVENTION
`
`It is an object ofthe present invention to attempt to provide a patient interface that goes
`
`some way to overcoming the abovementioned disadvantages in the prior art or which will at
`
`least provide the industry with a useful choice.
`
`In a first aspect the present invention consists in headgear for use with a respiratory
`
`mask comprising:
`
`a continuous and substantially curved elongate member extending in use below a
`
`patient’s nose,
`
`at least two headgear straps capable of attachment to the ends of said elongate member,
`
`and
`
`a mask attachment on said elongate member disposed to sit below or on one of said
`
`user’s nose, mouth, upper lip and an inlet to the mask, said attachment capable of receiving
`said mask.
`
`In a second aspect the present invention consists in a breathing assistance apparatus for
`
`use with delivery of respiratory gases to a user comprising:
`
`a mask having a base and body, said body having two flexible nasal pillows that in use
`
`rest in a substantially sealed manner against said user’s nares,
`
`a continuous and substantially curved elongate member extending in use below a
`
`5
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`patient’s nose,
`
`at least two headgear straps capable of attachment to the ends of said elongate member,
`
`and
`
`a mask attachment on said elongate member disposed below said user’s nose, said
`
`attachment capable of receiving said mask.
`
`In a third aspect the present invention consists in a breathing assistance apparatus for
`use with dclivery ofrespiratory gases to a user comprising:
`
`a mask comprising a body and a cushion, said cushion substantially forming a seal with
`
`said patient’s airways,
`
`headgear comprising substantially flexible, soft straps and a substantially continuous
`
`curved elongate member to which said mask is attached, said elongate member extending over
`
`said user’s cheeks, and
`
`wherein said mask has an inlet extension tube and said curved elongate member is
`
`attached or rests beneath said inlet extension tube, anchoring said mask to said user’s face in
`use.
`
`To those skilled in the art to which the invention relates, many changes in construction
`
`and widely differing embodiments and applications of the invention will suggest themselves
`
`without departing from the scope of the invention as defined in the appended claims. The
`
`disclosures and the descriptions herein are purely illustrative and are not intended to be in any
`
`sense limiting.
`
`In this specification where reference has been made to patent specifications, other
`
`external documents, or other sources of information, this is generally for the purpose of
`
`providing a context for discussing the features of the invention. Unless specifically stated
`
`otherwise, reference to such external documents is not to be construed as an admission that
`
`such documents, or such sources ofinformation, in anyjurisdiction, are prior art, or form part
`
`of the common general knowledge in the art.
`
`The invention consists in the foregoing and also envisages constructions ofwhich the
`
`following gives examples.
`
`BRIEF DESCRIPTION OF THE FIGURES
`
`Preferred forms of the present invention will now be described with reference to the
`
`accompanying drawings.
`
`6
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`

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`_5_
`
`Figure 1 is a block diagram of a humidified continuous positive airway pressure
`
`system as might be used in conjunction with the nasal mask of the present invention.
`
`Figure 2 is a perspective View of a first form of a patient interface that is nasal mask
`
`and headgear of the present invention.
`
`Figure 3 is an exploded view of the nasal mask and headgear of Figure 2.
`
`Figure 4 is a side View of a mask base of the nasal mask and headgear of Figure 2.
`
`Figure 5 is a perspective end view of the mask base of Figure 4.
`
`Figure 6 is an end View of a body of the nasal mask and headgear of Figure 2,
`
`particularly showing two nasal pillows.
`
`Figure 7 is a perspective view of the body of Figure 6.
`
`Figure 8 is a perspective View of a nasal mask ofthe first form ofthe present invention
`
`'
`
`*- but having alternative headgear that includes additional rigid extensions.
`
`Figure 9 is perspective view of a second form ofa patient interface and headgear ofthe
`
`present invention.
`
`Figure 10 is an exploded View of the patient interface and headgear of Figure 9.
`
`Figure 11 is an exploded View of a third form of a patient interface and headgear ofthe
`
`present invention.
`
`Figure 12 is an exploded view of a fourth form of a patient interface and headgear of
`
`the present invention.
`
`Figure 13 is a perspective View of a fifth form of a patient interface and headgear of
`
`the present invention.
`
`Figure 14 is an exploded view of the patient interface and headgear of Figure 13.
`
`Figure 15 is a perspective View of a sixth form of a patient interface and headgear of
`
`the present invention.
`
`Figure 16 is a perspective View of a seventh form ofa patient interface and headgear of
`
`the present invention.
`
`Figure 17 is a cross—seetional View of the patient interface of Figure 16.
`
`Figure 18 is a front view of a nasal pillow of Figure 6.
`
`Figures 1921 is a front View of the nasal pillows of Figure 6.
`
`Figures 19b to 19d are graphs of the gradients of various nasal pillow connecting
`surfaces.
`
`7
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`WO 2008/007985
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`_5_
`
`Figure 20 is a perspective View of an eighth form of a patient interface and headgear of
`
`the present invention.
`
`Figure 21 is a perspective View of the interface and headgear of Figure 20 showing
`
`inner pads on the arms of the headgear.
`
`Figure 22 is an exploded View of the interface and headgear of Figure 20.
`
`Figure 23 is a perspective View ofa ninth form of a patient interface and headgear the
`
`present invention.
`
`DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
`
`The breathing assistance apparatus of the present invention including masks and
`
`headgear as described in the preferred embodiments ofthis invention can be used in respiratory
`
`care generally or with a ventilator. It is described below with reference to use in a humidified
`
`CPAP system.
`
`A humidified Continuous Positive Airway Pressure (CPAP) system is shown in Figure
`
`1. A patient 1 is receiving humidified and pressurised gases through a patient interface 2
`
`connected to a humidified gases transportation pathway or inspiratory conduit 3. Alternative
`
`delivery systems may also be used such as, VPAP (Variable Positive Airway Pressure) and
`
`BiPAP (Bi-level Positive Airway Pressure) or numerous other forms ofrespiratory therapy. A
`
`nasal mask 2 is illustrated in Figure 7 but other masks such as oral, full face or nasal cannula
`
`may be used.
`
`An inspiratory conduit 3 is connected to an outlet 4 of a hurnidification chamber 5 that
`
`contains a volume of Water 6. The inspiratory conduit 3 may contain heating means or heater
`
`wires (not shown) that heat the walls of the conduit to reduce condensation of humidified
`
`gases within the conduit 3.
`
`The humidification chamber 5 is preferably formed from a plastics material and
`
`preferably has a highly heat conductive base (for example an aluminium base) that is in direct
`
`contact with a heater plate 7 of humidifier 8. The humidifier 8 is provided with control means
`
`or an electronic controller 9 that may comprise a microprocessor based controller executing
`
`computer software commands stored in associated memory.
`
`' The controller 9 preferably receives input from sources such as user input means or a
`
`dial 10 through which a user of the device may, for example, set a predetermined required
`
`value (preset value) of humidity or temperature of the gases supplied to patient 1. The
`
`controller 9 may also receive input from other sources, for example temperature and/or flow
`
`8
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`WO 2008/007985
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`
`_ 7 _
`
`velocity sensors 1 1, 12, through a connector 13 and a heater plate temperature sensor 14. In
`
`response to the user set humidity or temperature value input via the dial 10 and the other
`
`inputs, the controller 9 determines when (or to what level) to energise the heater plate 7 to heat
`
`the water 6 within the humidification chamber 5. As the Volume of the water 6 within the
`
`humidification chamber 5 is heated, water vapour begins to fill the volume of the chamber
`
`above the water’s surface and is passed out ofthe humidification chamber 5 outlet 4 with the
`
`flow of gases (for example air) provided from a gases supply means or blower 15 that enters
`
`the chamber 5 through an inlet 16. Exhaled gases from the patient’ s mouth are passed directly
`
`to the ambient surroundings in Figure 1.
`
`The blower 15 is provided with variable pressure regulating means or variable speed
`
`fan 21 that draws air or other gases through a blower inlet 17. The speed ofthe variable speed
`
`fan 21 is controlled by an electronic controller 18 (or alternatively the function of the
`
`controller 18 may be carried out by the controller 9) in response to inputs from the controller 9
`
`and a user set predetermined required value (preset Value) ofpressure or the fan speed via dial
`19.
`
`Figures 2 and 3 show a first embodiment of a patient interface ofthe present invention.
`
`This patient interface is a nasal mask 2. The nasal mask 2 is comprised ofa mask base 22 and
`
`body 23. The body 23 is substantially tubular with two nasal pillows 24, 25 extending from it.
`
`The nasal pillows 24, 25 are preferably frustoconical in shape and in use rest against a
`
`patient’s nares, to substantially seal the patient’s nares. The body 23 has an external lip 28 that
`
`frictionally fits in a channel in the mask base 22.
`
`The body 23 and nasal pillows 24, 25 of the nasal mask of the present invention are
`
`shown in further detail in Figures 6 and 7. The body and pillows are preferably integrally
`
`moulded in a substantially flexible plastics material.
`
`In the preferred form this material is
`
`silicone, but other appropriate materials, such as, rubber, thermoset clastomer or thermoplastic
`elastomer, such as KratonTM may be used.
`
`The nasal pillows 24, 25 are preferably an elliptical cone and as such are tubular and
`
`allow for a passage of gases to flow from the tubing 3 and through the mask body 23. . The
`
`pillows 24, 25 are preferably angled toward one another and each have a preferably elliptical
`
`30
`
`outlet 26, 27 that may be slightly offset from the centre of each pillow 24, 25, as shown in
`
`Figure 6.
`
`Figures 18 and 19a show a nasal pillow 24 with an offset outlet in more detail. The
`
`9
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`_ g _
`
`pillow 24 has an outer profile 200 and inner profile 201 with respective centre points 202, 203.
`
`The inner profile 201 (outlet of the nasal pillow 24) is offset inward, by a horizontal spacing
`
`204 and vertical spacing 205. Meaning the outlet 201 ofthe nasal pillow is offset horizontally
`
`204 towards the middle ofthe nose and vertically 205 towards the user’s upper lip. Offsetting
`
`the outlet 201 downwards in this manner allows the outlet to be inserted into a user’s nostril
`
`without the outer profile 200 pushing the user’s upper lip. Offsetting the outlet 201 inwards
`
`allows the pillow to better seal on the septum of the user’s nose in use.
`
`The outlet 201 may also be angled compared to the outer profile 200. For example in
`
`Figure 18, there is a horizontal angle difference between the outer profile 200 and outlet 201
`
`shown as 206. A similar vertical angle difference between the outer profile 200 and outlet 201
`is shown as 207.
`
`With the outer profile and inner profile having different sections or offsets allows the
`
`gradient of the connecting surface between the profiles to be changeable. This is shown in the
`
`graphs ofFigures 19b, 19c and 19d. The connecting surface between the inner 201 and outer
`
`200 profiles can have differing gradients, 208, 209, 210. The different gradients 208, 209, 210
`
`of the connecting surface are possible due to the difference in offset difference 21], 212
`
`(horizontal, vertical or angled) between the inner 201 and outer 200 profiles.
`
`There may also be a difference in the rate of change of the gradient (as illustrated in the
`
`difference between 208 and 210). ‘This allows easier insertion of the pillow 24 into a user’s
`
`nostrils due to more lead in and better sealing that may be achieved due to more ergonomic
`
`contouring of the connecting surface that contacts the user’ s nostril.
`
`Referring back to Figure 7, the external lip 28 on the mask body 23 is an area of
`
`reduced circumference around the tubular part of the body 23. A projection 47 may be
`
`provided on the lip 28 that fits with a corresponding recess or channel (discussed below) on the
`
`mask base 22 to ensure correct assembly of the nasal mask.
`
`The mask base 22 is shown in further detail in Figures 4 and 5. The mask base 22 is a
`
`ring or sleeve type attachment. The base 22 is preferably made from a substantially hard
`
`(rigid) plastics material, such as polypropylene, polycarbonate or acetyl. However, other
`
`appropriate materials may be used. The base 22 has an internal circumferential recessed area
`
`or channel 45 on one side and a semi-tubular projection 29 on its other side. When assembling
`
`the mask body 23 to the mask base 22 the channel 45 receives the lip 28. These parts are
`
`maintained together by friction fit, however other types offitting may be provided for, such as
`
`10
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`_ 9 _
`
`a snap or bump fitted part or the body may be over moulded to a clip that causes the fitting to
`
`the mask body 23.
`
`In this form the friction fitting of the lip 28 to the recessed area 45 is
`
`assisted by elongate projections 49 extending along the central part 50 of the mask base 22.
`
`The projection 47 on the mask body 23 allows for correct fitting or keying ofthe mask base to
`
`.
`
`the mask body, such that when the lip 28 is fitted into the recessed area 45, the projection 47 .
`enters the recess 48 formed in the mask base 22.
`
`The semi—tubular projection 29 is curved in this embodiment such that a ball jointed
`
`connector end 46 such that a connector 30 can be fitted into it. The projection 29 forms a
`
`socket for the connector end 46 and the comiector end can swivel within the socket. The
`
`connector 30 is attached to a tube 31 to allow for gases to be passed to the nasal mask 2. The
`
`tubing 31 may be attached to inspiratory conduit 3 or the tubing 31 may simply be the
`
`inspiratory conduit 3.
`
`In alternative embodiments the projection 29 may not be semi-circular but the inner
`
`surface of the base 22 may be curved and form a socket for receiving the connector end 46.
`
`The base 22 has an extension or partial lip 32 extending beneath the semi—tubular
`
`projection (socket) 29. A slot 33 is created between the socket 29 and extension 32. The
`
`extension and slot is used to fit the mask base 22 to the headgear 21. In this embodiment the
`
`extension 32 is substantially curved to follow the shaped ofthe projection 29. However, in
`
`other forms the extension may be substantially straight or otherwise shaped.
`
`In use, the nasal mask is assembled with headgear 21 . The headgear 21 in the preferred
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`fonn is comprised of headgear straps 35, 36, 37, 38 and a substantially curved and elongate
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`member 34. The member 34 is curved and substantially rigid, or at least more rigid than the
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`headgear straps.
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`The headgear straps 35, 36, 37, 38 are preferably made from a composite foam layered
`material, such as Breathoprenem. The headgear 21 preferably includes a first strap 35 and a
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`second strap 36. The first strap 35 extends in use over the forehead or top front area of a
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`patient’s head. The second strap 36 extends around the back of the patient’s head. The
`headgear 21 also has side straps 37, 38 that in use extend down the cheeks ofa patient and the
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`ends of the straps terminate in the upper lip area of the patient in use.
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`Referring to Figure 2, the curved and elongate member 34 is comprised of a central
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`Section 42 and Contoured Side arms 41, 54. A substantial length of each of the side arms 41,
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`54 overlaps and is attached to the side straps 37, 38. However, the side straps 37, 38 only
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`extend partially along the length ofthe side arms 41, 54 so as to terminate beneath the cheek or
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`near the upper lip region. As the side straps 37, 38 are made from a soft foam type material
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`they provide a comfortable fitting of the headgear and curved member 34, while the
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`substantially rigid side arms 41, 54 provide rigidity and stability to the headgear 21 and nasal
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`mask 2. The attachment between the side straps and rigid extension side arms may be made by
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`gluing, sewing or other appropriate fastening.
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`Preferably the side arms of the curved member 34 are integrally moulded with the
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`central section 42. The curved member 34 is preferably three dimensionally moulded to a
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`shape to substantially match the cheek contours of a human. The side arms 41, 54 are
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`preferably ofthinner width (cross—section) than the central section 42. As the side arms 41, 54
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`are moulded of a plastics material to be substantially thin they are capable of being bent or
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`adjusted to allow for better and more comfortable fit to a patient. The side arms 41, 54 may
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`also include weakened or narrow areas 39 to allow for additional bending, moulding or
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`twisting ofthe arms 41, 54 to better fit the headgear to individual patients. For example, in the
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`embodiment shown in Figures 2 and 3, the narrowed area 39 corresponds to the cheek bone
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`area of a patient and allows for the side arms 41, 54 to easier bend or twist to fit the contours
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`of the patient’s face.
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`In alternative embodiments the side arms may have weakened areas that are narrower
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`in cross—section to that of the remainder ofthe side arms. A narrower cross-section area would
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`also provide a weakened area that may be easily manipulated.
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`In alternative embodiments of the present invention the side straps ofthe headgear may
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`not extend under and along the length of the curved member but be attached to the distal ends
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`of the straps. This attachment may be by hook and loop material, as is known in the art, or by
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`other attachment methods as known in the art. In this form, the arms of the curved member
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`may have padding underneath them or no padding at all.
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`Referring to Figure 3, the curved elongate member has a central section 42 that in an
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`assembled form supports the mask base and body such that the pillows 24, 25 rest against the
`patient’s nares. The central section 42 is a half circle that is integrally moulded with the side
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`arms 41, 54. The central section 42 has a raised area 43 on its exterior, at the apex of the half
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`. circle. The raised area 43 is shaped to receive the mask base 22. To assemble, a patient
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`merely needs to slide the mask base 22 into the central section 42 such that the raised area 43
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`fits into the slot 33 on the mask base 22.
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`The side arms 41, 54 ofthe curved member 34 preferably have Varying cross—sectiona1
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`thickness. The ends of the arms 41, 54 attached to the central section 42 are thicker over the
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`most curved parts 55, S6 of the arms, whereas the straighter parts of the arms 57, 58 have a
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`narrow cross-section. Therefore, the thicker ends 55, 56 hold their shape better.
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`In alternative embodiments, the mask base 22 may be formed integrally with the curved
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`member 34. Therefore, the central section and base would be one and would not be able to be
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`separated from one another.
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`An example ofthis is shown in Figures 20 to 22, the eighth embodiment of the patient
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`interface and headgear 300. Here, the mask base 301 and the curved elongate member 302 are
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`integrally formed, for example, by moulding or the like. The elongate member comprises arms
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`303, 304 similar to that described above. Also the mask body 305 has integral nasal pillows
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`306, 307 similar to that described above in relation to Figure 2.
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`J;
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`As can be seen in Figures 21 and 22 in this eighth embodiment the headgear straps 308,
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`309 do not extend down the arms 303, 304 as with other embodiments. In this embodiment
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`the headgear straps 308, 309 attach through recesses 310, 313 at the end of the arms 303, 304
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`extending along the arms are inner pads 3 1 1,312 that rest against the patient’s cheekbones in
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`use and provide comfort to the patient’s face. The pads 311, 312 only extend up to near the
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`attachment recesses 309, 3 10. The pads are preferably made from a foam type material, such
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`as the laminated material that the headgear straps are made from. The pads 311, 312
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`preferably do not extend beyond the edges of the arms 303,304.
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`Referring back to Figures 2 and 3, alternatively, the curved member 34 may be formed
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`as two separate pieces. That is, the central section 42 may be formed as two parts with a
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`central split seam, the two left and right halves joined in use. The two left and right parts
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`could either be joined along a seam as described above, with the base 22 slotting into the slot
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`33 as described above, or alternatively, each ofthe two left and right arms may be attached one
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`to each side of the base 22.
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`Where a “substantially continuous elongate member” or “curved member” is referred
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`to in this specification, it refers to any of the options for the curved member 34 outlined above.
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`The side arms 41, 54 may also include a loop 40 or detached section. This is where a
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`section of the side arms 41 is not attached to the strap 38, 37 lying underneath. Thus the
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`detached section 40 of the side arms forms a loop to which a tubing attachment 44 (such as
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`that shown attached to another strap in Figures 2 and 3) may be looped to the side arms 41, 54
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`and the tubing 31 attached to either of the side arms.
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`_
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`The connector 30 in the preferred form is a ball and socket jointed connector to allow
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`for the tubing 31 to swivel in the mask base 22. The tubing 31 may be attached to any of the
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`headgear straps. However, a tube attachment 44 is shown where the tubing is attached by
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`fasteners, such as hook and loop fastener, to the first strap 35.
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`In other embodiments the
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`tubing 31 may be attached to either the side straps 37, 38 or merely allowed to fall freely from
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`the nasal mask 2.
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`Although a ball and socket joint, as described above, between the mask base 22 and
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`tubing 31 is preferred other connections may be utilised, such as a flexible piece of silicone, or
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`other appropriate connection. The connection between the base and tubing must be able to be
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`flexed or r