USRE41298E1 - Patient interfaces - Google Patents

Abstract

The present invention relates to a device for delivering a supply of gases to a patient. The device includes a patient interface and connecting member. The connecting member is preferably a L-shaped swivelled connector that is capable of being fixed into one of two positions, a first position where the connector is freely rotatable within the patient interface, and a second position where an interference between the interface and connector prevents the free rotation of the connector within the patient interface. The present invention further relates to a connector that has outlet means, which includes at least one outlet vent and a funnel, which in use directs and passes a substantial portion gases expired from the patient through the outlet vent or vents.

Description

BACKGROUND OF THE INVENTIONField of the Invention

This invention relates to patient interfaces, particularly though not solely for use in providing Continuous Positive Airway Pressure (CPAP) therapy or positive pressure ventilation to patients suffering from obstructive sleep apnoea (OSA).

SUMMARY OF THE PRIOR ART

In the art of respiration devices, there are well known 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 such that gas may be provided at positive pressure within the mask for consumption by the user. The uses for such masks range from high altitude breathing (ie. aviation applications) to mining and fire fighting applications, to various medical diagnostic and therapeutic applications.

One requisite of such respiratory masks has been that they provide an effective seal against the patient'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. 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.

Where such masks are used in respiratory therapy, in particular treatment of obstructive sleep apnoea (OSA) using continuous positive airway pressure (CPAP) therapy, there is generally provided in the art a vent for washout of the bias flow or expired gases to the atmosphere. Such a vent may be provided for example, as part of the mask, or in the case of some respirators where a further conduit carries the expiratory gases, at the respirator. A further requisite of such masks is the washout of gas from the mask to ensure that carbon dioxide build up does not occur over the range of flow rates. In the typical flow rates in CPAP treatment, usually between 4 cm H2O and 20 cm H2O, prior art attempts at such vents have resulted in excessive noise causing irritation to the user and any bed partners.

Various approaches have been developed in the prior art to attempt to reduce the noise when CPAP therapy is provided. For example, in PCT Patent Application No. WO98/34665 it has been proposed that the vent include a resilient plug with rounded edge apertures to reproduce noise. However, this is not entirely effective in eliminating the extra noise created by a vent at the mask.

In common with all attempts to improve the fit, sealing and user comfort is the need to avoid a concentrated flow of air at any portion of the respiratory tracts. In particular with oral masks or mouthpieces it is a disadvantage of prior art devices that the oral cavity may become overly dehydrated by use of the device, causing irritation and possible later complications.

SUMMARY OF THE INVENTION

It is an object of the present invention to attempt to provide a patient interface which goes some way to overcoming the abovementioned disadvantages in the prior art or which will at least provide the industry with a useful choice.

Accordingly in a first aspect the present invention consists in a device for delivering a supply of gases to a patient comprising or including:

• • a patient interface fittable to said patients' nose or mouth, which in use is in fluid communication with said supply of gases,
  • connecting member having two ends and interface means, one end of said two ends being locatable within said patient interface and the other end of said two ends is connectable to said supply of gases, said member capable of being fixed into one of two positions, a first position where said member is freely rotatable within said patient interface, and a second position where said interference means prevents the free rotation of said member within said patient interface.

In a second aspect the present invention consists in a continuous positive airways pressure system for delivering gases to a patient comprising or including a pressurised source of gases, transport means, in fluid communication with said pressurised source, adapted to convey said gases, and a nasal mask in fluid communication with said transport means, in use, delivering said gases to said user, said nasal mask comprising or including:

• • a body portion having an inlet, connected to said transportation means by a connecting member,
  • sealing means engaged with said body portion, and adapted to seal against the facial contours of said patient, and
  • securement means attached to or around the head of said user,
  • wherein said connecting member has two ends and interference means, one end being locatable within said patient interface and the other end of said two ends connectable to said transportation means, said connecting member capable of being fixed into one of two positions, a first position where said member is rotatable within said patient interface, and a second position where said interference means prevents the free rotation of said member within said patient interface.

In a third aspect the present invention consists in a device for delivering a supply of gases to a patient comprising:

• • a patient interface, which in use is in fluid communication with said supply of gases,
  • connecting member that connects said patient interface with said supply of gases,
  • outlet means associated with said connecting member, said outlet means including at least one outlet vent and a funnel, which in use directs and passes a substantial portion gases expired from said patient through said at least one outlet vent.

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.

BRIEF DESCRIPTION OF THE DRAWINGS

One preferred form of the present invention will now be described with reference to the accompanying drawings in which;

FIG. 1 is a block diagram of a humidified positive pressure ventilation system as might be used in conjunction with the present invention,

FIG. 2 is an illustration of the nasal mask in use according to the preferred embodiment of the present invention,

FIG. 3 is a side elevation view of an example of a connector used with a breathing circuit,

FIG. 4 is a perspective view from above of a mouthpiece that may be used with the elbow connector of the present invention,

FIG. 5 is a perspective view from one side and from an inward direction of the mouthpiece ofFIG. 4,

FIG. 6 is a cross-section of the mouthpiece ofFIG. 4,

FIG. 7 is a cross-sectional view of the mouthpiece ofFIG. 4 and a user with the mouthpiece in place to demonstrate the location and positioning thereof in relation to the main features of the patient's anatomy,

FIG. 8 is a perspective view of the mouthpiece with an outer flap in place,

FIG. 9 is a perspective view of the outer flap bent back,

FIG. 10 is a cutaway view of the mouthpiece with the outer flap in use,

FIG. 11 is a perspective view of the outer flap including the ventilation apertures and moisture barrier,

FIG. 12 is a front view of a nasal mask, including a swivelled elbow connection of the present invention,

FIG. 13 is a side view of the swivelled elbow connection as attached to the mask body of the present invention in a first position,

FIG. 14 is an exploded side view of the locking mechanism part of the swivelled elbow connection in the first position,

FIG. 15 is a side view of the swivelled elbow connection as attached to the mask body of the present invention, in a second position,

FIG. 16 is an exploded side view of the locking mechanism part of the swivelled elbow connection in the second position,

FIG. 17 shows a nasal mask body and elbow connector with diffuser,

FIG. 18 shows a cutaway side view of the bias flow director of the present invention, and

FIG. 19 shows a cutaway perspective view of the bias flow director of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides improvements in the delivery of positive pressure ventilation therapy. In particular a patient interface is described which is quieter for the user to wear and reduces the side leakage as compared with the prior art. The patient interface of the present invention includes improvements to the swivel elbow connector, bias flow directional funnel and/or elbow diffuser. It will be appreciated that the patient interface as described in the preferred embodiment of the present invention can be used in respiratory care generally or with a ventillator but will now be described below with reference to use in a humidified positive pressure ventilation system. It will also be appreciated that the present invention can be applied to any form of patient interface including, but not limited to, nasal masks, oral masks and mouthpieces.

With reference toFIG. 1, a humidified positive pressure ventilation system is shown in which a patient1 is receiving humidified and pressurised gases through apatient interface2 connected to a humidified gases transportation pathway orinspiratory conduit3. It should be understood that delivery systems could also be YPAP (Variable Positive Airway Pressure) and BiPAP (Bi-level Positive Airway Pressure) or numerous other forms of respiratory therapy.Inspiratory conduit3 is connected to the outlet4 of ahumidification chamber5, which contains a volume ofwater6.Inspiratory conduit3 may contain heating means or heater wires (not shown), which heat the walls of the conduit to reduce condensation of humidified gases within the conduit.Humidification chamber6 is preferably formed from a plastics material and may have a highly heat conductive base (for example an aluminium base) which is in direct contact with aheater plate7 ofhumidifier8.Humidifier8 is provided with control means orelectronic controller9 which may comprise a microprocessor based controller executing computer software commands stored in associated memory.

Controller9 receives input from sources such as user input means or dial10 through which a user of the device may, for example, set a predetermined required value (reset value) of humidity or temperature of the gases supplied to patient1. The controller may also receive input from other sources, for example temperature and/or flowvelocity sensors11 and12 throughconnector13 and heaterplate temperature sensor14. In response to the user set humidity or temperature value input viadial10 and the other inputs,controller9 determines when (or to what level) to energiseheater plate7 to heat thewater6 withinhumidification chamber5. As the volume ofwater6 withinhumidification chamber5 is heated, water vapour begins to fill the volume of the chamber above the water's surface and is passed out of thehumidification chamber5 outlet4 with the flow of gases (for example air) provided from a gases supply means orblower15 which enters the chamber throughinlet16. Exhaled gases from the patient's mouth are passed directly to ambient surroundings.

Blower15 is provided with variable pressure regulating means orvariable speed fan21, which draws air or other gases throughblower inlet17. The speed ofvariable speed fan21 is controlled by electronic controller18 (or alternatively the function ofcontroller18 could be carried out by controller9) in response to inputs fromcontroller9 and a user set predetermined required value (preset value) of pressure or fan speed viadial19.

Nasal Mask

A nasal mask that may be used with the improvements to the swivel elbow connector, bias flow directional funnel and/or elbow diffuser of the present invention is shown in FIG.2. The mask includes ahollow body102 with aninlet103 connected to theinspiratory conduit3. Themask2 is positioned around the nose of the user1 with theheadgear108 secured around the back of the head of the patient1. The restraining force from theheadgear108 on thehollow body102 and theforehead rest106 ensures enough compressive force on themask cushion104, to provide an effective seal against the patient's face.

Thehollow body102 is constructed of a relatively inflexible material for example, polycarbonate plastic. Such a material would provide the requisite rigidity as well as being transparent and a relatively good insulator.

The improved swivel elbow connector, bias flow directional funnel and/or elbow diffuser of the present invention may also be used with a mouthpiece as described below, or with a full facial mask.

Mouthpiece

Referring toFIGS. 3 to10 a mouthpiece that may utilise the improvements to the swivel elbow connector, bias flow directional funnel and/or elbow diffuser. In this embodiment, themouthpiece50 includes avestibular shield49 being a generally flat and generally rectangularly-shaped member in front elevation having a curved profile that reflects the curvature of a patient's jaw and in turn the curvature of the labial vestibule region A gases passageway extends through the vestibular shield from aninlet51 to anoutlet52 in much the same way as with the earlier embodiments. Theinlet51 is provided by a flattened oval-shapedconnector53. Theoutlet52 has an even more laterally extended flattenedoval shape54. Most prominently, themouthpiece50 includes atongue depressor55 extending from the inner face of thevestibular shield49. The operation of the tongue depressor will be described further on with reference to FIG.5. The tongue depressor includes avertical stiffening flange56 centrally located on its upper surface and extending from thegases outlet52. In use gases flow easily around the stiffeningflange56 effectively bifurcating thegases outlet52. Thetongue depressor55 further includes a pair of vertically extendingspacers57, which in use may abut against the roof of the patient's mouth and ensure that the tongue cannot completely block the air passageway. In themouthpiece50 the sealing effect of thevestibular shield49 against the lips of the user is enhanced by providing teeth abutments of significantly increased thickness than the raisedarea20 of the earlier embodiments. In particular, anupper teeth abutment58 and alower teeth abutment59 are provided, with thelower teeth abutment59 protruding further from the inner face of thevestibular shield49 than theupper teeth abutment58. This difference serves to match the typical over-bite of most users. Theabutments58 and59 are not required to be wider than thegases outlet52.

Anotch60 is provided centrally in the upper edge of thevestibular shield49 to accommodate the upper frenal attachment. Aslight bead61 is provided around the edge of thevestibular shield49 for user comfort, with thevestibular shield49 otherwise being very thin for additional suppleness.

Referring particularly toFIG. 6, themouthpiece50 is preferably formed by over-moulding a soft andsupple material part70 over astiffer material part67. These can generally be termed the shield part and the passageway-forming insert. The passageway-forming insert preferably includes a pair of upper and lowervertical flanges63 and64 to fully engage within the supple material. The passageway-forminginsert67 includes the vertically extendingstiffening flange56 of thetongue depressor55, together with a curvedplanar portion71 forming the backbone of thetongue depressor55. The vertically extendingspacers57 are of the soft and supple material and are part of the over-moulding70, as are the upper andlower teeth abutments58 and59.

Referring now toFIG. 7, use of the mouthpiece according toFIGS. 4 to6 is depicted. With thepresent mouthpiece50, the upper andlower lips85,86 are further distended by the abutment action of theabutments75,76 against the upper andlower teeth87,88 respectively, thus forming a seal of greater pressure between thelips85,86 and the upper and lower portions respectively of thevestibular shield49. Alower face77 of thetongue depressor55 impinges if necessary on theupper surface72 of thetongue85 and retains the tongue in the lower portion of the mouth. This ensures aclear gases outlet52 from the gases passageway through the vestibular shield. The vertically extendingspacers57, if forced by pressure from the tongue, will engage against the roof of the patient's mouth and maintain a clear air passageway. This stops the sleeping patient unconsciously blocking the oral passageway and reverting to nasal breathing.

Referring now toFIG. 8 of the present invention is illustrated including anextra-oral sealing flap110. Theflap110 in its natural bias is tapered, the wide-open end of which is shaped to conform to the facial contours around the outside of the mouth of a user. The narrow end joins to a cylindrical section, which is designed to slide over the inlet port114 of themouthpiece112. While this is one method of attachment the flap100 might also be constructed as an integral part of themouthpiece112. Theflap110 needs to be constructed of flexible material. Therefore, materials such as silicone rubber can be employed to fashion the flap.

Theouter flap110 is seen inFIG. 9, in a bent back position. It will be appreciated that when themouthpiece112 is being inserted into the mouth of a users theuser flap110 is intended to be in this bent back position to aid insertion. Prior to insertion, the outer flap is bent back by simply pressing on itsouter periphery116, until it snaps into the bent back position, in which it will stay unaided.

InFIG. 10 we see theouter flap110 in use with themouthpiece112 in themouth117 of auser120. Once correctly positioned in themouth116, theouter flap110 may be adjusted into its operational position by pressing on itsouter periphery116 until it snaps back to press against the outside of themouth118. Due to the relative position of thevestibular shield122 and theouter flap110, theouter flap110 is unable to fully reach its natural bias and thereby inflicts a compressive force on the outside of themouth118.

It will be appreciated that as well as providing a substantially airtight seal the addition of the outer flap provides enough compressive force on the mouth to keep the mouthpiece and conduit in place without the need for straps. This allows the administering of positive airway pressure ventilation therapy to be considerably less obtrusive than traditional methods.

In a further additional improvement shown inFIG. 11, theouter flap300 is shown in perspective. Included areventilation apertures302,303 either side of thegases port304, which are surrounded by aridge306 acting as a moisture barrier. Theapertures302,303 are provided such that any excess moisture leaking from the mouth will migrate to the apertures where they may evaporate. Small vents in the conduit may be used to direct small amounts of pressurised gas at the apertures to aid evaporation. Theridge306 is included to ensure that no moisture migrates further into the sealing region308, as this would be detrimental to the sealing properties of the flap.

Interface Connection

Attention is now directed to FIG.3. It has been found that an additional factor in the effectiveness of anypatient interface2, is the manner in which the interface is connected to the breathing circuit. The weight of the breathing circuit, and any attempted movement of one other of the breathing circuit and theinterface2 relative to the other, is one of the largest influences tending to dislodge theinterface2. It must be noted that theinterface2 must remain in position and maintain a seal during all sleep, when the user has no muscle tone.

The connection is usually provided between a breathing circuit and aninterface2, which decouples theinterface2 from the breathing circuit. This type of configuration is shown inFIG. 3, where the interface is a mouthpiece, although a nasal mask may be used in place of the mouthpiece. Theconnection40 is effective in reducing the forces placed on theinterface2 by thebreathing circuit41 when the user moves around during sleep.

To connect between thebases outlet42, which is vertical when the user is lying on his or her back, and thebreathing circuit41, which is generally horizontal, a L-shapedelbow connector45 is incorporated in theconnection40. Theelbow connector45 may be incorporated in theinterface2. Theelbow connector45 is formed at a right angle and provides a positive pressure on theinterface2. Theelbow connector45 may include a swivel joint and may be disconnected fromgaseous outlet42. Theconnection40 further includes a connectingtube46 provided between theelbow45 and thebreathing circuit41. The connectingtube46 is preferably connected to thebreathing circuit41 by a swivel joint48 for reasons described herein. Thebreathing circuit41, while flexible, will necessarily be stiff enough to maintain its inter over comparatively long tuns, while the flexible connectingtube46, being only a short length, for example 10 centimetres, merely has to span between the patient's mouth and chest, and can thereby be made in a manner that would not be suitable for long runs. Furthermore, as a result of the short length of the connectingtube46, the connectingtube46 does not need to incorporate significant insulation or heating capability. The connectingtube46 may be formed from a thin plastic membrane supported over helical or double helical or corrugated supporting ribs. In such a case, the support makes theconnection tube46 laterally flexible and resistant to torsion. Theelbow swivel connector45 allows for movement of theconnection tube46 relative to theinterface2. Theswivel connector48 allows for movement of theconnection tube46 relative to thebreathing circuit41. It is to be understood that one or both of the swivel joints45,48 could be eliminated, but the preferred embodiment includeselbow swivel connector48.

Fixable Swivel Joint

The nasal mask or mouthpiece as described above can be provided with an improved L-shaped elbow connector similar to that described above. Referring toFIGS. 12 to16 a L-shapedelbow401 is fixed to themask base402 on the nasal mask although not shown in the Figures toinlet51 of themouthpiece50. Hereinafter when reference is made to “mask body” or “mask base402” it is intended to refer to either the mask body orinlet51 of the mouthpiece. Aportion403 of the elbow connector can be rotated about a point X in the directions of arrows A and B. Theelbow connector401 is connectable at itsend404 to the breathing circuit orconduit3 as described with reference toFIGS. 1 and 2. Theconnector401 is designed to be fixed into one of two positions and is able to be fully removed from themask base402. If theconnector401 is assembled in a first position, it is able to freely swivel, as indicated by the arrows labelled A and B on FIG.12. If the elbow is pushed into a second position, an area of interference prevents the connector from freely swivelling.

Attention is now drawn toFIGS. 13 and 14 where themask body501 andelbow connector502 are shown in a first position where theconnector502 is able to freely rotate 360 degrees about a vertical axis out of the mask body. Theconnector502 is connected to an aperture in the centre of the mask body, so that in use, gases flow from the breathing circuit through the elbow connector and aperture in the mask body and into the patient's lungs. Theelbow connector502 is held within the aperture in themask body501 by way oftubular connector503 located on the arm of theelbow connector502. Thetubular connector503 comprises various ridges and protrusions, moulded in the external surface of the elbow connector's arm, that meet with complimentary ridges and protrusions moulded in the interior surface of the aperture in the mask body (or theinlet51 itself).

In particular, referring toFIG. 14, when theconnector502 is in the position as shown inFIG. 13, theridge601 andprotrusion602 in theconnector502 act with thesmall ridge603 andprotrusion604 in the interior surface of the mask body, to lock theelbow connector502 into a position that enables the elbow to swivel freely within the mask body. To remove theelbow502 from the mask body501 a force in the direction of arrow C (seeFIG. 13) must be placed on the elbow so that theprotrusion602 on the elbow is forced past theprotrusion604 on the mask body, thereby releasing theconnector502 from the mask body.

The elbow connector may be pushed downwards to into the mask body to a position as shown inFIGS. 15 and 16. Here, theprotrusion602 of the elbow has been pushed past thelower protrusion802 on themask body501 and sits within acomplimentary ridge801 in the mask. Theprotrusion604 on the mask abuts theridge601 on the elbow connector and theexterior side surface804 of the elbow connector above theridge601 abuts theinterior surface805 of the mask aperture. The area ofinterference803 between these surfaces prevents the elbow from freely swivelling within the mask.

The improvements, as described above, to the elbow connector of the present invention provides an attachment that can either freely rotate, or be locked in a particular position according to the patient's desires. The improvement to the prior art swivel connectors is that the short flexible tubing (46 as described with reference toFIG. 3) is no longer required.

Flow Diffuser and Bias Flow Directional Funnel

In an alternative form of the present invention, and in order to reduce the noise caused by expiratory gases being expelled from the mask or mouthpiece, either may be provided with an elbow connector having a diffuser. In prior art systems the flow diffuser is usually provided within the elbow connector at the point of connection to the mask body or inlet to the mouthpiece, in the present invention it is envisaged to provide a diffuser on the elbow connector. The following description refers to nasal mask when describing the diffuser. The diffuser may also be provided with an elbow connector used with a mouthpiece as previously described.

FIG. 17 shows anasal mask901 andelbow connector902 as that has a diffuser located along the length of theconnector902 previously. Theelbow connector902 includes adiffuser903 on its exterior surface, the diffuser is a duct that provides for the broadening of the airflow and reduction in the airflow speed. In the preferred form the duct has outlet vent holes904,905 and the duct is made out of flexible rubber material. Note must be made that any number of vent holes may be provided in the duct, the preferred form shown inFIG. 17, merely shows two vents. The duct is preferably provided with a bias flow directional funnel, which will be described below.

Referring toFIGS. 18 and 19, during positive pressure ventilation treatment a portion of the inlet air flow breathed by the patient is exhausted directly through the bias holes1001,1002. The only venting required is to clear the expired CO₂gas from within theelbow connector1003. Therefore afunnel1004 is provided within theelbow1003 that directs the exhaled CO, gases to the bias holes1001,1002 but does not direct the inlet airflow from the ventilation machine out the bias holes.

The purpose of the funnel is to vent exhaled air from the breathing system to remove CO₂gases. With the prior art breathing systems it has been found that there is continuous leaking of gases through the vent holes during inspiration and expiration by the patient. Therefore, a loss of pressure occurs due to escaping air. Thus, on inspiration the patient receives less pressure and thus less breathing therapy, and therefore this requires that vent holes are provided that are as small as possible to lessen this effect.

During expiration by the patient it is preferred that most of the exhaled gases are vented through the vent holes, in order to prevent pressure spikes and to ensure CO₂gases are expelled from the breathing tubing. The funnel therefore provides for shielding of the vent holes during inspiration, but enhances the venting of CO₂gases by providing directional flows during expiration, this also allows for vent holes to be increased in size, providing larger exhaust areas.

Inlet airflow E flows from the ventilating system through the elbow connector in the direction of arrows F, G and H and into the patient's lungs. The air that is exhaled, as indicated by arrow I, flows through thefunnel1004 that has been moulded within the interior of theelbow1003. Thefunnel1004 is tubular in shape and provides for the funnelling of the exhausted CO₂gases through the outlet bias holes1001,1002.

Providing such a diffuser on the elbow connector effectively minimises the noise generated by the outward flow of expiratory gases from the mask. The diffuser of the present invention requires little or no maintenance and improves user comfort.

The providing of a directional funnel within the elbow connector further minimises noise and reduces pressure spikes during exhalation.

Claims (12)

1. A device for delivering a supply of gases to a patient comprising or including:

a patient interface fittable to a patients nose or mouth, which in use is in fluid communication with said supply of gases,

connecting member having two ends and means for interference with said patient interface, one end of said two ends being locatable within said patient interface and the other end of said two ends is connectable to said supply of gases, said member capable of being fixed into one of two positions, a first position where said member is freely rotatable within patient interface, and a second position where said means for interference with said patient interface prevents the free rotation of the member within said patient interface.

2. A device for delivering a supply of gases to a patient according toclaim 1 wherein said other end is connected to a conduit that is connected to said supply gases.

3. A device for delivering a supply of gases to a patient according toclaim 1 wherein said connecting member is a L-shaped connector.

4. A device for delivering a supply of gases to a patient according toclaim 1, wherein said means for interference with said patient interface is the meeting of an interference surface on the connecting member that is capable of abutting said patient interface.

5. A device for delivering a supply of gases to a patient according toclaim 1 wherein said patient interface is a nasal mask.

6. A device for delivering a supply of gases to a patient according toclaim 1 wherein said patient interface is a mouthpiece.

7. A device for delivering a supply of gases to a patient according toclaim 5, wherein said nasal mask comprises or includes:

a body portion, having an inlet receiving said supply of gases through a gases supply conduit, and

sealing means attached to or integrated with said body portion, said sealing means adapted to seal against the facial contours of a patient.

8. A device for delivering a supply of gases to a patient according toclaim 7, wherein said connecting member includes outlet means, said outlet means including, at least one outlet vent and a funnel, which in use directs and passes a substantial portion of gases expired from a patient through said at least one outlet vent.

9. A continuous positive airways pressure system for delivering gases to a patient comprising or including a pressurized source of gases, a conduit, in fluid communication with said pressurized source, adapted to convey said gases, and a nasal mask in fluid communication with said conduit, in use, delivering said gases to a patient, said nasal mask comprising or including:

a body portion having an inlet, connected to said conduit by a connecting member,

sealing means engaged with said body portion, and adapted to seal against the facial contours of a patient, and

securement means attached to or around the head of a patient,

wherein said connecting member has two ends and means for interference with said body portion, one end being locatable within said body portion and the other end of said two ends connectable to said conduit, said connecting member capable of being fixed into one of two positions, a first position where said member is rotatable within said body portion and a second position wherein said means for interference with said body portion prevents the free rotation of said member within said body portion.

10. A device for delivering a supply of gases to a patient according toclaim 9 wherein said connecting member is an L-shaped connector.

11. A device for delivering a supply of gases to a patient according toclaim 9 wherein said means for interference with said body portion is the meeting of an interference surface on said connecting member that is capable of abutting said body portion.

12. A continuous positive airways pressure system for delivering gases to a patient according toclaim 9 wherein said connecting member includes outlet means, said outlet means including, at least one outlet vent and a funnel, which in use directs and passes a substantial portion of gases expired from a patient through said at least one outlet vent.

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