초록

A vent assembly for use with a mask assembly includes a first vent and a second vent having at least one different flow characteristic wherein the vent assembly can be switched between the first vent and the second vent to alter flow of exhaled gas from a patient.

대표청구항 ▼

1. A patient interface configured to deliver a flow of breathable gas at a continuously positive treatment pressure with respect to ambient air pressure, while a patient is sleeping, to an entrance to the patient's airways to ameliorate sleep disordered breathing, said patient interface comprising:

1. A patient interface configured to deliver a flow of breathable gas at a continuously positive treatment pressure with respect to ambient air pressure, while a patient is sleeping, to an entrance to the patient's airways to ameliorate sleep disordered breathing, said patient interface comprising: a frame forming a cavity configured to be pressurised at the treatment pressure by the flow of breathable gas;a patient contacting portion connected to the frame and configured to seal against an area surrounding the entrance to the patient's airways to deliver the flow of breathable gas to the patient's airways; anda gas washout vent configured to allow a vent flow of gas to pass to an exterior of the patient interface to minimise rebreathing of exhaled CO2 by the patient, the gas washout vent comprising an orifice, a first vent, and a second vent, the gas washout vent having a first position wherein the orifice is in pneumatic communication with the first vent, and the gas washout vent having a second position wherein the orifice is in pneumatic communication with the second vent,wherein a first visual indicator is associated with said first position and a second visual indicator is associated with said second position, andwherein the gas washout vent is configured to allow gas to pass freely out of and into the cavity via the gas washout vent. 2. The patient interface of claim 1, wherein a third visual indicator is fixed relative to the orifice. 3. The patient interface of claim 1, wherein the first vent comprises a first flow characteristic, wherein the second vent comprises a second flow characteristic, andwherein the first flow characteristic and the second flow characteristic are different. 4. The patient interface of claim 3, wherein the first flow characteristic comprises a first cross-sectional vent area, and wherein the second flow characteristic comprises a second cross-sectional vent area. 5. The patient interface of claim 4, wherein the orifice has a cross-sectional area greater than the first cross-sectional vent area and the second cross-sectional vent area. 6. The patient interface of claim 5, wherein the patient interface comprises a tubular member, the gas washout vent provided on said tubular member. 7. The patient interface of claim 6, wherein the gas washout vent is rotatable about a longitudinal axis of said tubular member between the first position and the second position. 8. The patient interface of claim 4, wherein the first cross-sectional vent area is greater than the second cross-sectional vent area, and wherein a first treatment pressure associated with the first cross-sectional vent area is smaller than a second treatment pressure associated with the second cross-sectional vent area. 9. The patient interface of claim 1, wherein the gas washout vent is configured to provide visual, tactile, and/or audible feedback to the patient when the gas washout vent is changed between the first position and the second position. 10. The patient interface of claim 1, wherein the gas washout vent is positioned on the frame. 11. The patient interface of claim 1, further comprising a swivel elbow configured to be connected to an air delivery conduit to receive the flow of breathable gas generated by a flow generator, wherein the gas washout vent is positioned on the swivel elbow. 12. A patient interface for delivery of a flow of breathable gas at a continuously positive treatment pressure with respect to ambient air pressure, while a patient is sleeping, to an entrance to the patient's airways to ameliorate sleep disordered breathing, said patient interface comprising: a frame forming a cavity configured to be pressurised at the treatment pressure by the flow of breathable gas;a patient contacting portion connected to the frame and configured to seal against an area surrounding the entrance to the patient's airways to deliver the flow of breathable gas to the patient's airways; anda gas washout vent configured to allow a vent flow of gas to pass from the cavity to an exterior of the patient interface to minimise rebreathing of exhaled CO2 by the patient, the gas washout vent comprising a first tubular member and a second tubular member,wherein the first tubular member comprises an orifice and the second tubular member comprises a first vent and a second vent, andwherein the first tubular member has a longitudinal axis, and the first tubular member and the second tubular member are rotatable relative to one another about the longitudinal axis to align the first vent or the second vent with at least a portion of the orifice to allow the vent flow of gas to pass to the exterior of the patient interface during use. 13. The patient interface of claim 12, wherein the gas washout vent has a first position wherein the orifice is in pneumatic communication with the first vent, and the gas washout vent has a second position wherein the orifice is in pneumatic communication with the second vent. 14. The patient interface of claim 12, wherein the first vent has a first flow characteristic and the second vent has a second flow characteristic, and wherein the first flow characteristic and the second flow characteristic are different. 15. The patient interface of claim 14, wherein the first flow characteristic comprises a first cross-sectional vent area, and wherein the second flow characteristic comprises a second cross-sectional vent area. 16. The patient interface of claim 15, wherein the orifice has a cross-sectional area greater than the first cross-sectional vent area and the second cross-sectional vent area. 17. The patient interface of claim 15, wherein the first cross-sectional vent area is greater than the second cross-sectional vent area, and wherein a first treatment pressure associated with the first cross-sectional vent area is smaller than a second treatment pressure associated with the second cross-sectional vent area. 18. The patient interface of claim 12, wherein the gas washout vent is configured to provide visual, tactile, and/or audible feedback to the patient when the gas washout vent is rotated about the longitudinal axis. 19. The patient interface of claim 12, wherein the gas washout vent is positioned on the frame. 20. The patient interface of claim 12, further comprising a swivel elbow configured to be connected to an air delivery conduit to receive the flow of breathable gas generated by a flow generator, wherein the gas washout vent is positioned on the swivel elbow. 21. The patient interface of claim 12, wherein the gas washout vent is configured to allow gas to travel freely out of and into the cavity. 22. The patient interface of claim 12, wherein the orifice is positioned on a curved side of the first tubular member, and wherein the first vent and the second vent are positioned on a curved side of the second tubular member. 23. A patient interface for delivery of a flow of breathable gas at a continuously positive treatment pressure with respect to ambient air pressure, while a patient is sleeping, to an entrance to the patient's airways to ameliorate sleep disordered breathing, said patient interface comprising: a frame forming a cavity configured to be pressurised at the treatment pressure by the flow of breathable gas;a patient contacting portion connected to the frame and configured to seal against an area surrounding the entrance to the patient's airways to deliver the flow of breathable gas to the patient's airways; anda gas washout vent configured to allow a flow of gas to pass from the cavity to an exterior of the patient interface to minimise rebreathing of exhaled CO2 by the patient, the gas washout vent comprising a first tubular member and a second tubular member,wherein the first tubular member comprises an orifice and the second tubular member comprises a vent, the orifice and the vent being alignable to allow the flow of gas to pass through the gas washout vent to the exterior of the patient interface during use, andwherein the first tubular member has a longitudinal axis, and the first tubular member and the second tubular member are rotatable relative to one another about the longitudinal axis to vary a cross-sectional area of a flow path of the flow of gas through the gas washout vent to the exterior of the patient interface. 24. The patient interface of claim 23, wherein the first tubular member and the second tubular member have a first relative position and a second relative position, the cross-sectional area of the flow path of the flow of gas through the gas washout vent to the exterior of the patient interface being different in the first relative position and the second relative position. 25. The patient interface of claim 23, wherein the orifice has a greater cross-sectional area than the vent. 26. The patient interface of claim 23, wherein the gas washout vent is configured to provide visual, tactile, and/or audible feedback to the patient when the gas washout vent is rotated about the longitudinal axis. 27. The patient interface of claim 23, wherein the gas washout vent is positioned on the frame. 28. The patient interface of claim 23, further comprising a swivel elbow configured to be connected to an air delivery conduit to receive the flow of breathable gas generated by a flow generator, wherein the gas washout vent is positioned on the swivel elbow. 29. The patient interface of claim 23, wherein the gas washout vent is configured to allow gas to travel freely out of and into the cavity. 30. The patient interface of claim 23, wherein the orifice is positioned on a curved side of the first tubular member, and wherein the vent is positioned on a curved side of the second tubular member.