Breathing assistance apparatus

1. A breathing assistance apparatus comprising:

a mask body being hollow and having an opening, the opening configured to receive a nose, or nose and mouth, of a patient, the hollow of the mask body having a coupling portion that defines at least a portion of a breathing cavity, the mask body being formed of a relatively inflexible material that provides rigidity for the mask;

a sealing interface arranged to surround the opening in the mask body and configured to be joined to the coupling portion that defines at least a portion of the breathing cavity, the sealing interface configured to be joined to the coupling portion of the mask body in a sealing manner and the sealing interface being configured to seal around the patient's facial contours, at least a portion of the sealing interface being formed of a relatively softer plastics material when compared to the relatively inflexible material of the mask body, the sealing interface comprising an outer sealing member and an inner sealing member, the outer sealing member having a thin region and a thick region, the thin region being located in a nasal bridge region configured to extend over and contact a patient's nasal bridge in use, the inner sealing member being absent in the nasal bridge region; and

a vent configured to allow expiratory gases to be expelled and an elbow connector configured to connect between a conduit and the mask body.

2. The breathing assistance apparatus of claim 1 , wherein a first end of the elbow connector comprises an arrangement of slots configured to allow a portion of the elbow to deflect as the elbow is joined to the mask body.

3. The breathing assistance apparatus of claim 1 , wherein the thin region is approximately half a thickness of the thick region.

4. The breathing assistance apparatus of claim 1 , wherein the sealing interface is coupled to the mask body via a snap-fit.

5. The breathing assistance apparatus of claim 1 , wherein a mounting portion of the sealing interface is configured to join to the coupling portion of the mask body, the mounting portion of the sealing interfacing comprising two walls that define a channel.

6. The breathing assistance apparatus of claim 5 , wherein at least one of the two walls is received in a channel defined in coupling portion of the mask body.

7. The breathing assistance apparatus of claim 1 , wherein the sealing interface is a full face mask.

8. The breathing assistance apparatus of claim 1 , wherein the inner sealing member is made of silicone.

9. The breathing assistance apparatus of claim 1 , wherein the mask body is made of polycarbonate.

10. The breathing assistance apparatus of claim 1 , wherein the outer sealing member is made of silicone.

11. The breathing assistance apparatus of claim 1 , wherein a side wall of the elbow comprises one or more openings.

12. The breathing assistance apparatus of claim 1 further comprising a forehead rest, wherein a rigid arm extends between and connects the mask body and the forehead rest.

13. The breathing assistance apparatus of claim 12 further comprising headgear configured to apply a restraining force to the forehead rest to secure the breathing assistance apparatus to the patient.

14. The breathing assistance apparatus of claim 1 , the outer sealing member comprising a lip defining a patient-contacting surface that surrounds the opening, the opening having an uppermost extent, wherein a width of the thin region tapers inward between an upper edge of the lip and the uppermost extent of the opening.

15. The breathing assistance apparatus of claim 14 , wherein the thin region extends all the way to, and defines a portion of, a periphery of the opening.

16. The breathing assistance apparatus of claim 15 , wherein each side of the thin region intersects the opening below the uppermost extent.

17. A breathing assistance apparatus comprising:

a mask body being hollow and having an opening, the opening configured to receive a nose, or nose and mouth, of a patient; and

a mask cushion configured to be joined to the mask body and arranged to surround the opening in the mask body, the mask cushion configured to seal around the patient's facial contours, the mask cushion having at least one indented section configured to accommodate the patient's facial contours, and the mask cushion comprising:

an outer sealing sheath and an inner sealing member, the outer sealing sheath having a thin region located in a nasal bridge region and configured to extend over and contact a patient's nasal bridge in use, the thin region having a reduced cross-sectional thickness compared to a remainder of the outer sealing sheath;

the inner sealing member being absent in the nasal bridge region.

18. The breathing assistance apparatus of claim 17 , wherein the at least one indented section comprises a contoured region along a lower section of the mask cushion.

19. The breathing assistance apparatus of claim 18 , wherein the contoured region is configured to seal around a section beneath the patient's nose and above the patient's upper lip.

20. The breathing assistance apparatus of claim 17 , further comprising a forehead rest.

21. The breathing assistance apparatus of claim 17 , further comprising headgear configured to be secured around a back of the patient's head.

22. The breathing assistance apparatus of claim 17 , wherein the inner sealing member is made of silicone.

23. The breathing assistance apparatus of claim 17 , wherein the outer sealing member is made of silicone.