US20240017030A1 - Method and apparatus for managing moisture buildup in pressurised breathing systems - Google Patents
Method and apparatus for managing moisture buildup in pressurised breathing systems Download PDFInfo
- Publication number
- US20240017030A1 US20240017030A1 US18/361,651 US202318361651A US2024017030A1 US 20240017030 A1 US20240017030 A1 US 20240017030A1 US 202318361651 A US202318361651 A US 202318361651A US 2024017030 A1 US2024017030 A1 US 2024017030A1
- Authority
- US
- United States
- Prior art keywords
- vent
- hydrophilic material
- vent assembly
- coplanar
- patient
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000029058 respiratory gaseous exchange Effects 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title description 7
- 239000000463 material Substances 0.000 claims abstract description 106
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000004033 plastic Substances 0.000 claims description 35
- 229920003023 plastic Polymers 0.000 claims description 35
- 239000004753 textile Substances 0.000 claims description 16
- 210000004379 membrane Anatomy 0.000 description 37
- 239000012528 membrane Substances 0.000 description 37
- 230000002209 hydrophobic effect Effects 0.000 description 35
- 239000011148 porous material Substances 0.000 description 24
- 239000010410 layer Substances 0.000 description 21
- 230000037361 pathway Effects 0.000 description 13
- 238000013022 venting Methods 0.000 description 13
- -1 e.g. Substances 0.000 description 12
- 230000000241 respiratory effect Effects 0.000 description 12
- 239000004698 Polyethylene Substances 0.000 description 9
- 230000007423 decrease Effects 0.000 description 8
- 229920000573 polyethylene Polymers 0.000 description 7
- 230000002829 reductive effect Effects 0.000 description 6
- 239000000758 substrate Substances 0.000 description 6
- 238000004891 communication Methods 0.000 description 5
- 238000010276 construction Methods 0.000 description 5
- 230000009471 action Effects 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 230000007246 mechanism Effects 0.000 description 4
- 239000011241 protective layer Substances 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- 229920000742 Cotton Polymers 0.000 description 3
- 239000004743 Polypropylene Substances 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- 230000005494 condensation Effects 0.000 description 3
- 210000001061 forehead Anatomy 0.000 description 3
- 239000004519 grease Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 208000001797 obstructive sleep apnea Diseases 0.000 description 3
- 230000036961 partial effect Effects 0.000 description 3
- 229920001155 polypropylene Polymers 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 229910001220 stainless steel Inorganic materials 0.000 description 3
- 239000010935 stainless steel Substances 0.000 description 3
- 206010011906 Death Diseases 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 230000005660 hydrophilic surface Effects 0.000 description 2
- 230000014759 maintenance of location Effects 0.000 description 2
- 238000007726 management method Methods 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 208000023504 respiratory system disease Diseases 0.000 description 2
- 230000000452 restraining effect Effects 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 206010003497 Asphyxia Diseases 0.000 description 1
- 206010007559 Cardiac failure congestive Diseases 0.000 description 1
- 206010019280 Heart failures Diseases 0.000 description 1
- 208000008589 Obesity Diseases 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 208000006011 Stroke Diseases 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001010 compromised effect Effects 0.000 description 1
- 208000012696 congenital leptin deficiency Diseases 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000002788 crimping Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 206010012601 diabetes mellitus Diseases 0.000 description 1
- 235000012489 doughnuts Nutrition 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000001595 flow curve Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 210000003128 head Anatomy 0.000 description 1
- 230000005661 hydrophobic surface Effects 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 230000003434 inspiratory effect Effects 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003020 moisturizing effect Effects 0.000 description 1
- 208000001022 morbid obesity Diseases 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000010137 moulding (plastic) Methods 0.000 description 1
- 210000002850 nasal mucosa Anatomy 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000004439 roughness measurement Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 201000002859 sleep apnea Diseases 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 238000001356 surgical procedure Methods 0.000 description 1
- 238000002560 therapeutic procedure Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/06—Respiratory or anaesthetic masks
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/06—Respiratory or anaesthetic masks
- A61M16/0605—Means for improving the adaptation of the mask to the patient
- A61M16/0633—Means for improving the adaptation of the mask to the patient with forehead support
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/06—Respiratory or anaesthetic masks
- A61M16/0605—Means for improving the adaptation of the mask to the patient
- A61M16/0633—Means for improving the adaptation of the mask to the patient with forehead support
- A61M16/0644—Means for improving the adaptation of the mask to the patient with forehead support having the means for adjusting its position
- A61M16/065—Means for improving the adaptation of the mask to the patient with forehead support having the means for adjusting its position in the form of a pivot
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/08—Bellows; Connecting tubes ; Water traps; Patient circuits
- A61M16/0816—Joints or connectors
- A61M16/0841—Joints or connectors for sampling
- A61M16/085—Gas sampling
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/08—Bellows; Connecting tubes ; Water traps; Patient circuits
- A61M16/0816—Joints or connectors
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/08—Bellows; Connecting tubes ; Water traps; Patient circuits
- A61M16/0816—Joints or connectors
- A61M16/0825—Joints or connectors with ball-sockets
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/08—Bellows; Connecting tubes ; Water traps; Patient circuits
- A61M16/0816—Joints or connectors
- A61M16/0841—Joints or connectors for sampling
- A61M16/0858—Pressure sampling ports
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/10—Preparation of respiratory gases or vapours
- A61M16/1045—Devices for humidifying or heating the inspired gas by using recovered moisture or heat from the expired gas
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2202/00—Special media to be introduced, removed or treated
- A61M2202/02—Gases
- A61M2202/0208—Oxygen
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2205/00—General characteristics of the apparatus
- A61M2205/02—General characteristics of the apparatus characterised by a particular materials
- A61M2205/0238—General characteristics of the apparatus characterised by a particular materials the material being a coating or protective layer
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2205/00—General characteristics of the apparatus
- A61M2205/42—Reducing noise
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2205/00—General characteristics of the apparatus
- A61M2205/58—Means for facilitating use, e.g. by people with impaired vision
- A61M2205/581—Means for facilitating use, e.g. by people with impaired vision by audible feedback
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2205/00—General characteristics of the apparatus
- A61M2205/58—Means for facilitating use, e.g. by people with impaired vision
- A61M2205/583—Means for facilitating use, e.g. by people with impaired vision by visual feedback
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2205/00—General characteristics of the apparatus
- A61M2205/75—General characteristics of the apparatus with filters
- A61M2205/7527—General characteristics of the apparatus with filters liquophilic, hydrophilic
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2205/00—General characteristics of the apparatus
- A61M2205/75—General characteristics of the apparatus with filters
- A61M2205/7536—General characteristics of the apparatus with filters allowing gas passage, but preventing liquid passage, e.g. liquophobic, hydrophobic, water-repellent membranes
Definitions
- the present invention relates to a method and apparatus for managing moisture buildup in humid pressurized breathing systems subject to humidity consideration, etc., e.g., breathable gas supply apparatus for use in Continuous Positive Airway Pressure (CPAP) treatment of Obstructive Sleep Apnea (OSA) and various other respiratory disorders, and diseases.
- CPAP Continuous Positive Airway Pressure
- OSA Obstructive Sleep Apnea
- a respiratory mask is provided with a vent affording reduced noise and/or improved vent flow under humidified gas flow conditions.
- CPAP treatment devices typically provide a gas flow generator for delivering pressurized breathable gas, usually air, to a patient's airway using a conduit and mask.
- the gas flow generator is combined with a humidifier to deliver pressurized humidified gas.
- the pressurized and optionally humidified gas acts as a pneumatic splint for the patient's airway, preventing airway collapse, especially during the inspiratory phase of respiration.
- the humidified gas minimizes drying of the nasal mucosa and increases patient comfort.
- Many standard vents for respiratory masks have adverse reduced flow when used with humidified air, either due to the build up of moisture at the entry to the vent or the blocking of the small gas pathways through the vent.
- the vent manufactured by Gottsch Weinmann Gerate Fur Medizin Und Anlagenschutz GmbH & Co. is known to reduce the vent flow when used with humidified gas. See European Patent No. 0 697 225 A2 to Gottlieb et al.
- the blockage of the small gas pathways through the vent is a particular problem at low pressures such as 4 cm of H 2 O or below. Blockage may occur because pressure is insufficient to keep the pathways clear. In this event, the minimum flow condition for safe CO 2 washout may be compromised, especially at the low end of the pressure treatment range.
- One aspect of the invention is directed to providing a super quiet vent for use in medical masks, e.g., for sleep apnea treatment.
- the vent can be in the form of a diffuser vent that can maintain flow even in wet and/or humid conditions.
- a vent gas flow path is constructed to provide sufficient venting under humidified gas flow conditions, any obstructions in the vent due to moisture in the outflowing gas or remaining after washing being minimized or eliminated.
- the vent is constructed to displace or reduce the moisture from the venting pathway. This may be accomplished by preventing moisture from entering the vent pathway or facilitating movement of the moisture away from the vent pathway.
- the vent configuration may be disposed or created within the mask shell or maybe disposed in additional piping extending from the mask, in both cases enabling the outflow of gas, e.g., from the inner cavity within the mask, to atmosphere.
- a respiratory mask comprising a mask body having a patient interface at least in part defining a breathing cavity, and a gas washout vent in communication with the cavity and including a porous portion, the porous portion including a hydrophobic or hydrophilic material.
- the porous portion may take the form of a porous insert, a porous disk, a plastic portion, a porous sintered plastic, a membrane (with one or more holes), a textile and/or a plastic lined with a textile.
- the porous portion may be made of plastic material, e.g., polyethylene and/or polypropylene, and it may have a granular structure or a surface structure (e.g., smooth, rough, one or more sides).
- the porosity may be in the range of about 120-220 ⁇ m. Depending on the thickness the porous portion may also serve as a filter. 120-220 ⁇ m is the ideal range as a balance between having the lowest noise production, adequate resistance to blockage with humidity, and an appropriate size to be included in a mask system. For ideal noise the porosity should be as fine as possible ( ⁇ 120 ⁇ m). For ideal resistance to blockage the porosity should be as coarse as possible (>220 ⁇ m).
- a finer porosity vent however requires a much larger surface area to provide sufficient vent flow and a size limit therefore exists as to how low the porosity can be depending on the amount of space provided for the vent in the mask design. To this end, the greatest surface area available is the entire surface of the mask frame, and in the extreme a mask frame could be made entirely of material that has super fine porosity, implementing the finest porosity whilst still affording sufficient vent flow.
- a respiratory mask comprises a mask body having a patient interface at least in part defining a breathing cavity; and a gas washout vent in communication with the cavity and including a textile material on one side of the vent for wicking away moisture from the vent.
- a respiratory mask comprises a patient interface defining an opening communicating between a breathing cavity and an exterior of the patient interface, and a moisture retention channel formed adjacent the opening.
- a respiratory mask comprises a patient interface defining an opening in communication between a breathing cavity and an exterior of the patient interface, a port in communication with the breathing cavity, wherein the port has at least one portion formed of or treated with a hydrophilic and/or hydrophobic material.
- vent or port may include hydrophobic and/or hydrophilic materials per se, or they may be treated with such.
- vent or port or mask generally may simply be made of materials that simulate or have hydrophilic and/or hydrophobic properties.
- a method for managing moisture and/or humidity in a pressurized breathing system comprising at least a selected portion of the mask manufactured from a material suited to manage moisture and/or humidity.
- a vent assembly including porous material having different porosities in different regions.
- a variable vent in another embodiment, includes a closure mounted on at least one hydrophilic expansion member.
- a closure mounted on at least one hydrophilic expansion member.
- the closure may be made from a porous material or a non-porous material having a hole(s) therethrough.
- a conical hole venting arrangement is provided.
- a porous plug is positionable within the conical hole (or may be integrally formed therein), and when so arranged, a flange of the plug is disposed on an outside surface of the frame.
- the volume of the conical plug is greater than it would otherwise be if a cylindrical plug were provided (i.e. one with a diameter corresponding to the small end of the conical plug) and thus advantageously is able to absorb more moisture.
- the porous plug includes a core region having a lower level of porosity and a surrounding infill region (of substantially trapezoidal or triangular cross-section) having a higher level of porosity. This arrangement causes moisture absorbed by the core region to wick outwardly and upwardly to allow air to pass through the vent more freely.
- the porous plug includes a number of porous substrates disposed transversly across the hole, wherein the material of adjacent substrates have a decreasing level of porosity towards the flange region of the plug. In one embodiment between two and five porous substrates are provided.
- FIG. 1 is a perspective view of a CPAP treatment device in the form of a respiratory mask and illustrating a vent constructed in accordance with a preferred embodiment of the present invention
- FIG. 2 is a view similar to FIG. 1 illustrating a different preferred configuration of mask and vent;
- FIGS. 3 and 4 are partial cross-sectional views of a vent assembly according to different embodiments of the present invention.
- FIG. 5 is a fragmentary perspective view illustrating a mask having a removable vent
- FIGS. 5 a and 5 b illustrate graphically the difference of how hydrophilic and hydrophobic materials interact with water, where the size of the orifice (that a droplet resides in) approaches the size of the droplet;
- FIGS. 5 c through 5 f are partial cross-sectional views of vent assemblies according to embodiments of the present invention.
- FIGS. 6 a through 6 c illustrate various embodiments of vent material with variable porosity
- FIG. 7 a is a fragmentary cross-sectional view of a vent channel for removing moisture prior to the gas flow encountering the vent;
- FIG. 7 b is a view similar to FIG. 7 a illustrating a vent channel adjacent the exit of the vent;
- FIG. 8 a is an enlarged fragmentary view of a vent in a respiratory mask according to a further embodiment of the present invention.
- FIG. 8 b shows side-by-side cross-sectional comparative views of vent pathways with smooth and roughened surfaces, respectively;
- FIG. 8 c graphically illustrates roughness measurement of a vent orifice according to an embodiment of the present invention
- FIGS. 9 a - 9 c are schematic illustrations of further vent arrangements hereof;
- FIGS. 10 and 11 are comparative graphs of flow rate versus pressure, illustrating non-humidified vent flow versus vent flow with humidification.
- FIG. 12 is a comparative graph of the decrease in vent flow rate versus pressure for a prior art vent and a vent hereof.
- FIGS. 13 a and 13 b show schematic side views of a variable vent according to a further embodiment of the present invention.
- FIG. 14 is a schematic side view of a conical hole venting arrangement according to another embodiment of the present invention, including a porous plug.
- FIG. 15 is a schematic side view of a conical hole venting arrangement according to one embodiment of the present invention, including a plug having a core region of a lower level of porosity and a surrounding infill region having a higher level of porosity.
- FIG. 16 is a schematic side view of a conical hole venting arrangement according to another embodiment of the present invention, including a plug having a number of porous substrates disposed transversely across the plug, adjacent substrates decreasing in porosity towards an outer substrate.
- FIG. 17 is a schematic view of an exemplary mask.
- FIG. 1 illustrates a breathing system in the form of a patient interface, e.g., a nasal respiratory mask 10 , according to a first embodiment of the invention.
- Mask 10 includes a rigid plastic mask shell 12 that has a peripheral flange 14 for mounting a cushion 11 to the shell 12 (see FIG. 17 ).
- the cushion 11 abuts the wearer's face in use and is well known in the art.
- the flange 14 includes slots 15 for the connection of mask restraining straps (not shown) that extend around the head of the wearer to maintain the mask 10 adjacent the wearer's face.
- the straps are also known in the art.
- the shell 12 also includes an arm 16 which terminates in a fitting 18 adapted to connect to a forehead support (not shown), which is also known in the art.
- the mask shell 12 includes a breathable gas inlet 20 , e.g., in the form of a swivel elbow that is rotatably mounted to the shell 12 .
- the inlet 20 has a first end 22 adapted for connection with a breathable gas supply conduit (not shown) coupled to a gas generator for supplying gas under pressure.
- Inlet 20 has a second end 24 , which is adapted to connect to and communicate the supplied pressurized gas to the interior of the shell 12 for subsequent communication with the wearer's airway.
- Mask 10 also includes a gas washout vent including an opening 26 in the shell 12 across which extends porous portion in the form of a thin air permeable membrane 28 , e.g., in the form of a porous disk or insert.
- the porous portion may take the form of a plastic portion, a porous sintered plastic, a textile and/or a plastic lined with a textile.
- the porous portion may be made of plastic material, e.g., polyethylene and/or polypropylene), and it may have a granular structure or a surface structure (e.g., smooth, rough, etc., on one or more surfaces or sides), and the porosity may be in the range of 120-220 ⁇ m. Depending on the thickness the porous portion may also serve as a filter.
- FIG. 2 discloses a similar nasal respiratory mask 40 , wherein like reference numerals are used to describe like parts as in the first embodiment of FIG. 1 .
- the mask 40 has a shell 12 with a gas inlet 20 .
- the mask shell includes openings 42 forming part of a bracket 43 , which is adapted to snap engage with connection fittings (not shown) provided on the end of mask restraining straps (also not shown).
- the mask 40 includes an adjustable forehead support mechanism, indicated generally by the reference numeral 44 .
- mask 40 also includes a vent including an opening 26 formed in the gas inlet across which extends a thin permeable membrane 28 . While these and other forms of masks are well known, the two forms specifically disclosed herein are representative of the various known forms of masks and the washout vent described below may be utilized in any one or more of those or other known masks.
- a washout vent 48 which includes a membrane 50 interposed between an outer mask element 52 and an inner mask element 54 .
- the membrane 50 is essentially clamped between the two elements.
- the elements 52 and 54 have registering openings 56 and 58 and the membrane 50 spans across the registering openings 56 and 58 .
- FIG. 4 there is illustrated another way of mounting the membrane 50 , similarly as in FIG. 3 , spanning the opening 56 of an outer mask element 52 .
- the membrane 50 is secured solely to the inner surface of the outer element 52 and is not clamped between the two elements.
- the mask shell 12 has an opening 57 , which receives a removable holder 59 .
- Holder 59 is preferably hollow and cylindrical and is releasably retained in the opening 57 .
- the holder 59 includes an interior membrane 60 spanning the orifice through holder 59 .
- a grid 62 is carried by holder 59 outwardly of the membrane 60 for protecting the membrane 60 .
- the membranes illustrated in FIGS. 1 - 5 are preferably formed of or coated with a hydrophobic material.
- the membranes could be treated with surface affecting processes, e.g., nano treatment, coating, etc., similar to concrete treatment.
- a surface formed of or otherwise having hydrophobic properties of hydrophobic material repels moisture and water droplets. Consequently, if the vent surfaces or the entry to the vent surfaces are formed of hydrophobic material, the surfaces will resist moisture build up through the gas pathways of the vent as well as at the entry to the vent. The surfaces repel the moisture or water droplets and encourage the moisture or water droplets to run off the contacted hydrophobic surfaces.
- the hydrophobic material may be porous portion in the form of a porous plastic material and formed from such porous plastics as polyethylene, polypropylene, PVDF and PTFE. These materials naturally resist water entry into their pores. These materials are preferably sintered to form the porous construction. Alternatively, the material may be derived from a reticulated or cellular/matrix structure creating one or a plurality of small tortuous paths for gas.
- vent constructions and configurations there are many different forms of vent constructions and configurations.
- the formation of the membrane of, or providing a vent coated with hydrophobic material will cause a moisture droplet to sit higher off the vent surface. This may increase its proximity to the opposite vent surface tending to block the vent pathway.
- vents formed of or coated with a hydrophilic material are beneficial.
- the formation of the vent or coating or otherwise treating or providing the vent with a hydrophilic material reduces the tendency of the moisture to remain within and block the vent pathway. As the moisture approaches the exit of the vent, the hydrophilic surfaces wick away the moisture thereby reducing blockage of the vent gas flow.
- the hydrophilic surface simply allows the air to pass because the droplet has a low profile.
- FIG. 5 a shows a vent hole 50 . 5 having a diameter defined by an inner surface that is formed or treated with a hydrophobic material
- FIG. 5 b shows a similar vent hole 50 . 6 provided or treated with a hydrophilic material.
- Each vent hole 50 . 5 , 50 . 6 is approximately the same size, yet the water droplet in FIG. 5 a tends to more fully occlude the vent hole as compared to the relatively more open vent hole in FIG. 5 b.
- the vent hole 56 . 1 may have a cross-section having a composite or laminate construction, e.g., including two or more layers, such as a hydrophilic layer 56 . 2 and a hydrophobic layer 56 . 3 .
- FIG. 5 d shows a relatively thin porous portion having a thickness of around 1-2 mm, in the form of a membrane 50 . 1 that is thinner than the adjacent wall/frame structure 52 . 1 supporting the porous portion.
- FIG. 5 e shows a relatively thick porous portion having a thickness of 1 to 20 mm and preferably 3 to 7 mm.
- the relatively thick porous portion is in the form of a porous disk (e.g., a depth filter 50 . 2 —a filter that has some depth to it (not a thin filtration membrane)) that is thicker than the supporting frame/wall 52 . 2 .
- FIG. 5 f is a cross-section of a porous portion in the form of a snap-fit plastic member 50 . 3 that is removable/attachable to a frame 52 . 3 .
- hydrophilic material aside from the collection or channeling of moisture, is to prevent moisture from blocking and/or adversely affecting other parts or ports of the mask used to convey gas.
- most masks include a pressure port or an O 2 therapy port on the frame (e.g., frame 12 in FIG. 1 ) which can be fitted for formed with a hydrophilic material to prevent fouling of the port.
- This aspect and other aspects of the invention may be applied to any fluid (e.g., air) transmission orifice or orifices whereby control or management of moisture is desirable.
- the hydrophilic material may comprise a porous plastic material, such as hydrophilic polyethylene manufactured by Porex Corporation of Fairburn, Georgia.
- a porous plastic material such as hydrophilic polyethylene manufactured by Porex Corporation of Fairburn, Georgia.
- Other suitable material such Porex Porous Plastic and Oriented Fiber hydrophilic products can be designed to wick moisture and water droplets at different rates. See, for example, U.S. Pat. No. 6,638,610, issued Oct. 28, 2003, incorporated herein by reference.
- Porous Plastic may be naturally hydrophobic, such material can be made hydrophilic if treated, e.g., with a surfactant.
- the pore size may be 120-270 ⁇ m, preferably 170-220 ⁇ m, and the product may have a 5-35 mm diameter (e.g., about 20 mm) and a 1-10 mm thickness (e.g., about 5 mm). It has been found that these dimensions result in a balance of low noise and maintaining adequate flow even in humid conditions.
- the use of hydrophilic sintered plastic vents affords efficient airflow for CO 2 removal while eliminating much of the vent flow noise associated with traditional venting methods.
- the vents are produced in plastic moldings preferably using a sintering process and may be molded into any geometry achievable by injection molding technology.
- the materials used in the mask and vent may be co-moldable and thereby facilitate or eliminate assembly issues.
- the vent 26 may also be located in any pathway component of the mask 10 , such as the frame 12 , elbow 20 , cushion clip, forehead support, anti-asphyxia valve, cushion 11 or swivel, or air supply or venting pipes. See FIG. 17 .
- the interface component e.g., mask frame
- the interface component can be manufactured from the stated materials, therefore providing a number of utilities or functions for components, thus potentially reducing the number of parts, which can result in ease of use and reduced manufacturing costs.
- the entire frame 12 of FIG. 1 or the elbow 20 of FIG. 2 could be made of the stated materials.
- the feature or component including the materials can be an add-on, molded-on, retrofit or completely integral.
- the hydrophilic porous plastic such as the Porex Porous Plastics noted above, is advantageous in that it can be easily cleaned with a mildly abrasive cleanser to remove dirt, grease, smudges and the like. Heavy grease or oils may be removed with a solvent.
- the gas e.g., air
- the sintered plastic hydrophobic or hydrophilic material such that the pressure difference between the inside of the mask or other piping and the atmosphere drives the gas through the fine pores of the material itself into the atmosphere.
- This has the effect of exhausting the air to atmosphere in a highly diffuse manner. Forcing the gas through the tiny tortuous paths in the sintered plastic material generates a high magnitude of viscous loss in the air. This causes the air to vent to atmosphere at very low velocity for a given bulk flow rate, and hence produces minimal noise.
- a generally higher surface area is required for vents of this type as compared with conventional venting orifices. The required area will depend greatly upon the porosity and thickness of the material used for the vent.
- the vent membranes may be formed of a hydrophobic or hydrophilic material, which has variable porosity across the thickness of the membrane. Variable porosity in these materials may be achieved in the manufacturing process or by using a layer of material having a variable porosity.
- the hydrophobic or hydrophilic sintered porous plastic material forming the membrane 50 may have a fine pore size present at the entry to the vent and a larger pore size at the exit of the vent.
- the direction of the gas flow venting through the membrane 50 is represented by the arrow 70 .
- FIG. 1 The direction of the gas flow venting through the membrane 50 is represented by the arrow 70 .
- the fine pore size is represented by the smaller circles 72 within the membrane adjacent the gas entry surface of the membrane in contrast to the larger pore size represented by the circles 74 adjacent the opposite gas exit surface of the membrane.
- the hydrophobic or hydrophilic sintered porous plastic material may have the coarse pore size 74 at the entry surface of the vent and the finer pore size at the exit surface of the vent.
- a particular advantage of the use of a variable porosity material is that it enables a surface which is less likely to be blocked by moisture to be presented to highly humidified gas at the entry of the vent and a surface that is less likely to be blocked by dirt to reside at the exit of the mask where it may come into contact with dirt or grease.
- variable porosity of the membrane may be achieved by layering materials of different porosities.
- the entry to the vent membrane represented by the small circles 72 may be formed of a hydrophobic or hydrophilic sintered plastic material having the fine pore size in a first layer 76 on the entry side of the vent.
- An exit 78 formed of a hydrophobic or hydrophilic sintered plastic material having a coarse pore size represented by the larger circles 74 may be provided on the opposite side of the vent.
- the interior layer may be formed of hydrophobic material covering or partly covering a hydrophilic layer which is at the exterior of the mask.
- the hydrophilic material may constitute an interior layer at the entry to the vent, i.e., about the interior of the mask encouraging the humidified gas to flow through the vent.
- the exterior layer constituted by the hydrophobic material may encourage moisture, e.g., remnants of moisture from a prior washing of the vent, to run off the vent and mask and prevent blocking of the vent.
- a layer 80 of either hydrophilic and/or hydrophobic porous material may be positioned prior to the gas entry to the vent 82 . This inhibits build up of moisture at the entry of the vent.
- the interior layer 80 may only be partial, e.g., donut shaped or annular, thus allowing humidified gas to pass unfiltered through an opening in the center of the layer, or other openings thereof, but still preventing the build up of moisture about the entry to the vent.
- the vent 82 may be formed of conventional vent material, such as sintered metal or may be formed of the hydrophobic or hydrophilic material. The material may also be structured to increase the surface area within a smaller overall size vent. Increased surface area may be implemented using pleats, etc.
- a layer 86 of hydrophilic or hydrophobic porous material is positioned adjacent the exit side of the vent 88 . In both cases using the hydrophobic or hydrophilic materials tends to flow moisture away from the vent openings.
- FIGS. 7 a and 7 b include a washout vent structure mounted on a selectively removable holder similar to that shown in FIG. 5 .
- the vent could also be mounted directly on the frame (or along another portion of the gas delivery path), e.g., as described in U.S. Pat. Nos. 6,561,190 and 6,561,191, incorporated herein by reference in its entirety).
- FIGS. 7 a and 7 b may include a moisture collection area, e.g., in the form of a trough or channel that may be placed in the vicinity of the opening of the frame.
- a moisture collection area e.g., in the form of a trough or channel that may be placed in the vicinity of the opening of the frame.
- the trough is in front of the opening, but it could also be positioned on the inside of the frame.
- vent 90 and optionally the overall mask frame where the vent is situated may be formed of the porous, sintered plastic hydrophobic and/or hydrophilic materials described herein.
- the surfaces of the vent passage 90 may have a roughened finish.
- vent passages 92 which are continuous and smooth, albeit the walls of the passages undulate.
- the masks are made of molded polycarbonate, and may even have a small degree of roughness.
- the walls of the passages 94 are illustrated as having highly roughened surfaces (e.g., like the roughened surfaces which are generated using rapid prototype components (Objet®/SLA)—component made from a rapid prototyping process using stereolithography which deposits consecutive fine layers of plastic material according to input from a 3-D CAD model.
- Roughened surfaces of hydrophobic or hydrophilic material are particularly desirable as the vents produce reduced noise.
- the roughness can be quantified in terms of the ratio of the thickness of the roughened portion in relation to the overall height (or diameter) (H) of the orifice, as shown in FIG. 8 c .
- the roughness (R) should be in the range of H/50 ⁇ R ⁇ H/2, and preferably H/10 ⁇ R ⁇ H/5. Thus, if H is 0.7 mm, the roughness R will be between about 0.07 mm and 0.14 mm.
- an exemplary roughness of H/20 is shown in one region and a preferred roughness of H/5 is shown in another region.
- the dimension is defined as the height difference between the trough and the apex of the asperity.
- the properties of the hydrophobic or hydrophilic materials assist in moisture management, e.g., to wick moisture and/or to maintain the vent orifices open thereby minimizing risk of blockage with moisture.
- non-porous hydrophobic or hydrophilic material specifically plastic, which contains a number of venting holes (e.g., through holes) each having a diameter of up to 0.8 mm may be utilized.
- the vent may be formed from non-hydrophilic or non-hydrophobic material and later coated with hydrophilic or hydrophobic material.
- the preferred arrangement is similar to that described in the stainless steel embodiment of U.S. Pat. No. 6,581,594, where the holes are smaller than 0.2 mm in diameter.
- a further preferred embodiment similar to the stainless steel embodiment provided in U.S. Pat. No.
- the vent has a thickness of approximately 0.45 mm and a number of holes, each hole having a diameter of approximately 0.1 mm.
- the total open area of such a stainless steel membrane is approximately 5%.
- the vent geometry may take the form of any tapered or non-tapered vent geometry that is known in the art with a hydrophilic or hydrophobic coating enhancing the use of the vent with humidified air.
- a laminated textile may be used to provide the vent so that the vent has self-wicking capability.
- a plastic vent 100 containing small holes 102 may be provided as a low noise solution vent surrounded by a cotton based material 104 that has a capillary action.
- the cotton material 104 surrounding the vent 100 wicks the water from the vent.
- the wicking action may be along a direction D that is transverse to the axis of the holes 102 . 1 , as shown in FIG. 9 c . and can be directed towards an adjacent membrane or part of the same membrane.
- FIG. 9 a a plastic vent 100 containing small holes 102 may be provided as a low noise solution vent surrounded by a cotton based material 104 that has a capillary action.
- the wicking action may be along a direction D that is transverse to the axis of the holes 102 . 1 , as shown in FIG. 9 c . and can be directed towards an adjacent membrane or part of the same membrane.
- a textile 110 such as cotton, may be applied as a protective layer in front of the vent 112 .
- the protective layer captures the moisture and acts to wick the moisture away from the vent, while the flow passes through the protective layer and through the small holes in the low noise vent.
- an extension of this mechanism is to wick the moisture away to a membrane where it can be subsequently exposed to the breathing gas flow, therefore acting as a humidifier for the breathing gas.
- a heated textile or conductive yarn with a current supplied to it can surround the plastic vent or each individual vent hole.
- the textile prevents condensation of the humidified gas due to the raised temperature of the vent surface.
- the heated textile may also continue into the air path, e.g., into the mask frame, to increase the exposed area and increase humidity of the breathing gas and/or temperature, especially desirable in cooler climates.
- Wicking can be accomplished using a yarn material stitched together closely to allow moisture to capillate between yarns or it may also be at the fiber level, wherein each yarn is capable of capillary action.
- the textile fabric that holds moisture can have a dual utility in that the trapped moisture may be rebreathed to assist with moisturizing and/or humidifying the breathing air.
- a mask frame 140 includes a vent assembly 142 .
- the vent assembly 142 has a patient side 144 and an outside 146 .
- the frame 140 includes an orifice 141 having a generally conical shape, with the narrow end of the vent on the patient side 144 of the mask. This will allow more area for the moisture to move to when absorbed.
- Porous material 148 is arranged within the orifice 141 and extending to the outside of the frame.
- An additional porous layer 149 would be on the outside of the frame. This extra area would act as a sponge drawing water away from the vent and helping control the vent flow. See FIG. 14 .
- FIG. 15 Another embodiment of the vent of FIG. 14 is shown in FIG. 15 .
- This embodiment involves a core 150 of less porous material surrounded by a more porous outer layer. The more porous area would act as a wick for the moisture to move through. An outer layer on the mask would also be required for moisture dissipation. See FIG. 15
- Another embodiment of the above would have multiple layers 160 of porous material that would absorb moisture at different rates. See FIG. 16 . Initial condensation will occur on the layer that is on the patient side of the vent. The moisture will then be attracted into the layers above and out to the outer surface of the mask.
- FIG. 10 there is illustrated a graph of flow rate through the vent versus pressure using a sintered polyethylene hydrophilic vent before and four hours after humidification. As illustrated in this graph, even with humidified air, the flow rate does not decrease substantially and decreases no more than 15% at any pressure. The flow rate is safe even at low pressures, with and without humidity.
- FIG. 11 there is a similar graph comparing vent flow before humidification and vent flow after four hours of humidification with a sintered porous vent constructed in accordance with the Gottlieb European patent previously identified. This graph illustrates very low flow (potentially unsafe CO2 washout) even without humidity. With humidity, the flow is dangerously low.
- the graph indicates the percentage decrease in flow rate at various pressures for the Gottling sintered porous vent as compared with a sintered polyethylene hydrophilic vent hereof, the performance of which is set forth in FIG. 10 .
- the graph of FIG. 12 demonstrates the decrease in flow rate utilizing the hydrophilic vent structure of an embodiment of the present invention (designated “PE”) in comparison with the Gottsch vent designated “WM”.
- PE hydrophilic vent structure of an embodiment of the present invention
- WM the decrease in flow rate of the present invention is advantageously considerably less than the decrease in flow rate of the Gottlich vent.
- the vent designated as “PE” provided adequate flow for CO 2 washout, even at lower treatment pressures—both without and with humidity.
- an outer protective layer or plate 62 may be provided outside the vent membrane 60 and may comprise a coarse mesh or bars which protects the membrane from damage from large contaminants and handling.
- the protective plate or mesh may be eliminated if the vent is recessed within the mask frame or within the removable holder 58 .
- An end-of-life indicator may be mounted on or adjacent to the vent to alert the user to the need to replace the vent.
- the indicator may provide an indication of the elapsed time that the vent has been in use, blockage of the vent due to humidity or blockage of the vent due to contamination or reduced vent flow rate.
- the indicator may be either visual or audible.
- the indicator may include a water soluble dye that gradually washes away, similar to wear indicators provided in some tooth brushes.
- variable vent can be implemented to compensate the flow reduction.
- a layer of porous material 130 is mounted on feet 132 in a slotted hole 134 .
- the feet 132 are made of a hydrophilic material that expands when moist. This expansion lifts the porous material 130 out of the hole creating a vent in the gap between the frame and vent. See FIG. 13 a . Crimping the edge of the hole could reduces noise through variable vent.
- the flow reduction in the vent equals the flow increase created by the expanding feet.
- variable vent When the feet dry out (release moisture), they will shrink, reducing flow through the variable vent see FIG. 13 b .
- the reduction in flow of the variable vent equals the increase in flow through the porous vent as it dries out.
- variable vent is used in conjunction with a traditional vent. Instead of a porous vent being attached to the feet, a nonporous material is used. The flow increase of the variable vent counteracts the flow decrease caused by humidification at the traditional vent.
Abstract
A vent assembly is configured to discharge gas washout from a patient interface that is configured to receive a pressurized flow of breathable gas from a positive airway pressure device. The vent assembly includes a vent base configured to be attached to the patient interface and comprising a plurality of coplanar openings and a hydrophilic material positioned adjacent to the coplanar openings. The hydrophilic material is configured to wick water near the plurality of coplanar openings and/or capture moisture from a gas washout flow adjacent to the plurality of coplanar openings. In addition, the hydrophilic material is configured to release the accumulated moisture and/or water to the pressurized flow of breathable gas for breathing by the patient when the patient inhales.
Description
- This application is a continuation of U.S. application Ser. No. 16/918,432, filed Jul. 1, 2020, now allowed, which is a continuation of U.S. application Ser. No. 15/629,115, filed Jun. 21, 2017, abandoned, which is a continuation of U.S. application Ser. No. 11/988,541, filed Jan. 10, 2008, now U.S. Pat. No. 9,717,870, which is the U.S. national phase of International Application No. PCT/AU2006/001081, filed 31 Jul. 2006, which designated the U.S. and claims the benefit of U.S. Provisional Application No. 60/703,456, filed Jul. 29, 2005, each of which is incorporated herein by reference in its entirety.
- The present invention relates to a method and apparatus for managing moisture buildup in humid pressurized breathing systems subject to humidity consideration, etc., e.g., breathable gas supply apparatus for use in Continuous Positive Airway Pressure (CPAP) treatment of Obstructive Sleep Apnea (OSA) and various other respiratory disorders, and diseases. In one example, a respiratory mask is provided with a vent affording reduced noise and/or improved vent flow under humidified gas flow conditions.
- CPAP treatment devices typically provide a gas flow generator for delivering pressurized breathable gas, usually air, to a patient's airway using a conduit and mask. In many such devices, the gas flow generator is combined with a humidifier to deliver pressurized humidified gas. The pressurized and optionally humidified gas acts as a pneumatic splint for the patient's airway, preventing airway collapse, especially during the inspiratory phase of respiration. The humidified gas minimizes drying of the nasal mucosa and increases patient comfort. Many standard vents for respiratory masks have adverse reduced flow when used with humidified air, either due to the build up of moisture at the entry to the vent or the blocking of the small gas pathways through the vent. For example, the vent manufactured by Gottlieb Weinmann Gerate Fur Medizin Und Arbeitsschutz GmbH & Co. is known to reduce the vent flow when used with humidified gas. See European Patent No. 0 697 225 A2 to Gottlieb et al. The blockage of the small gas pathways through the vent is a particular problem at low pressures such as 4 cm of H2O or below. Blockage may occur because pressure is insufficient to keep the pathways clear. In this event, the minimum flow condition for safe CO2 washout may be compromised, especially at the low end of the pressure treatment range.
- Further, standard vents, including low noise vents, sometimes encounter obstruction of the gas vent pathway following washing of the mask or vent. Moisture can be retained around the entry or the exit of the vent or within the internal pathways of the vent. At low pressures immediately following a washing of the mask or vent, considerable time may elapse before the moisture is cleared. If the mask is in use while the vent is being cleared, the system has reduced airflow leading to undesirable retention of CO2 within the mask.
- One aspect of the invention is directed to providing a super quiet vent for use in medical masks, e.g., for sleep apnea treatment. The vent can be in the form of a diffuser vent that can maintain flow even in wet and/or humid conditions.
- In another aspect of the present invention, a vent gas flow path is constructed to provide sufficient venting under humidified gas flow conditions, any obstructions in the vent due to moisture in the outflowing gas or remaining after washing being minimized or eliminated.
- In another aspect of the present invention, the vent is constructed to displace or reduce the moisture from the venting pathway. This may be accomplished by preventing moisture from entering the vent pathway or facilitating movement of the moisture away from the vent pathway.
- It will be appreciated that in many aspects of the present invention, the vent configuration may be disposed or created within the mask shell or maybe disposed in additional piping extending from the mask, in both cases enabling the outflow of gas, e.g., from the inner cavity within the mask, to atmosphere.
- In one example of the present invention, there is provided a respiratory mask comprising a mask body having a patient interface at least in part defining a breathing cavity, and a gas washout vent in communication with the cavity and including a porous portion, the porous portion including a hydrophobic or hydrophilic material. The porous portion may take the form of a porous insert, a porous disk, a plastic portion, a porous sintered plastic, a membrane (with one or more holes), a textile and/or a plastic lined with a textile. The porous portion may be made of plastic material, e.g., polyethylene and/or polypropylene, and it may have a granular structure or a surface structure (e.g., smooth, rough, one or more sides). The porosity may be in the range of about 120-220 μm. Depending on the thickness the porous portion may also serve as a filter. 120-220 μm is the ideal range as a balance between having the lowest noise production, adequate resistance to blockage with humidity, and an appropriate size to be included in a mask system. For ideal noise the porosity should be as fine as possible (<120 μm). For ideal resistance to blockage the porosity should be as coarse as possible (>220 μm). A finer porosity vent however requires a much larger surface area to provide sufficient vent flow and a size limit therefore exists as to how low the porosity can be depending on the amount of space provided for the vent in the mask design. To this end, the greatest surface area available is the entire surface of the mask frame, and in the extreme a mask frame could be made entirely of material that has super fine porosity, implementing the finest porosity whilst still affording sufficient vent flow.
- In a further embodiment, a respiratory mask comprises a mask body having a patient interface at least in part defining a breathing cavity; and a gas washout vent in communication with the cavity and including a textile material on one side of the vent for wicking away moisture from the vent.
- In a further embodiment, a respiratory mask comprises a patient interface defining an opening communicating between a breathing cavity and an exterior of the patient interface, and a moisture retention channel formed adjacent the opening.
- In a further embodiment, a respiratory mask comprises a patient interface defining an opening in communication between a breathing cavity and an exterior of the patient interface, a port in communication with the breathing cavity, wherein the port has at least one portion formed of or treated with a hydrophilic and/or hydrophobic material.
- The vent or port may include hydrophobic and/or hydrophilic materials per se, or they may be treated with such. Alternatively, the vent or port or mask generally may simply be made of materials that simulate or have hydrophilic and/or hydrophobic properties.
- According to yet another embodiment, there is provided a method for managing moisture and/or humidity in a pressurized breathing system comprising at least a selected portion of the mask manufactured from a material suited to manage moisture and/or humidity.
- According to yet another embodiment there is provided a vent assembly including porous material having different porosities in different regions.
- These and other aspects will be described in or apparent from the following detailed description of preferred or exemplary embodiments.
- In another embodiment a variable vent is provided and includes a closure mounted on at least one hydrophilic expansion member. When humid air condenses in the vent and/or on the expansion member, at least some of the condensation is absorbed by the expansion member causing it to expand. Expansion of the expansion member configures the closure in an open configuration whereby air may pass more easily through the vent. The closure may be made from a porous material or a non-porous material having a hole(s) therethrough.
- In a further embodiment, a conical hole venting arrangement is provided. A porous plug is positionable within the conical hole (or may be integrally formed therein), and when so arranged, a flange of the plug is disposed on an outside surface of the frame. The volume of the conical plug is greater than it would otherwise be if a cylindrical plug were provided (i.e. one with a diameter corresponding to the small end of the conical plug) and thus advantageously is able to absorb more moisture.
- In one alternative embodiment the porous plug includes a core region having a lower level of porosity and a surrounding infill region (of substantially trapezoidal or triangular cross-section) having a higher level of porosity. This arrangement causes moisture absorbed by the core region to wick outwardly and upwardly to allow air to pass through the vent more freely.
- In another embodiment the porous plug includes a number of porous substrates disposed transversly across the hole, wherein the material of adjacent substrates have a decreasing level of porosity towards the flange region of the plug. In one embodiment between two and five porous substrates are provided.
-
FIG. 1 is a perspective view of a CPAP treatment device in the form of a respiratory mask and illustrating a vent constructed in accordance with a preferred embodiment of the present invention; -
FIG. 2 is a view similar toFIG. 1 illustrating a different preferred configuration of mask and vent; -
FIGS. 3 and 4 are partial cross-sectional views of a vent assembly according to different embodiments of the present invention; -
FIG. 5 is a fragmentary perspective view illustrating a mask having a removable vent; -
FIGS. 5 a and 5 b illustrate graphically the difference of how hydrophilic and hydrophobic materials interact with water, where the size of the orifice (that a droplet resides in) approaches the size of the droplet; -
FIGS. 5 c through 5 f are partial cross-sectional views of vent assemblies according to embodiments of the present invention; -
FIGS. 6 a through 6 c illustrate various embodiments of vent material with variable porosity; -
FIG. 7 a is a fragmentary cross-sectional view of a vent channel for removing moisture prior to the gas flow encountering the vent; -
FIG. 7 b is a view similar toFIG. 7 a illustrating a vent channel adjacent the exit of the vent; -
FIG. 8 a is an enlarged fragmentary view of a vent in a respiratory mask according to a further embodiment of the present invention; -
FIG. 8 b shows side-by-side cross-sectional comparative views of vent pathways with smooth and roughened surfaces, respectively; -
FIG. 8 c graphically illustrates roughness measurement of a vent orifice according to an embodiment of the present invention; -
FIGS. 9 a-9 c are schematic illustrations of further vent arrangements hereof; -
FIGS. 10 and 11 are comparative graphs of flow rate versus pressure, illustrating non-humidified vent flow versus vent flow with humidification; and -
FIG. 12 is a comparative graph of the decrease in vent flow rate versus pressure for a prior art vent and a vent hereof. -
FIGS. 13 a and 13 b show schematic side views of a variable vent according to a further embodiment of the present invention; -
FIG. 14 is a schematic side view of a conical hole venting arrangement according to another embodiment of the present invention, including a porous plug. -
FIG. 15 is a schematic side view of a conical hole venting arrangement according to one embodiment of the present invention, including a plug having a core region of a lower level of porosity and a surrounding infill region having a higher level of porosity. -
FIG. 16 is a schematic side view of a conical hole venting arrangement according to another embodiment of the present invention, including a plug having a number of porous substrates disposed transversely across the plug, adjacent substrates decreasing in porosity towards an outer substrate. -
FIG. 17 is a schematic view of an exemplary mask. -
FIG. 1 illustrates a breathing system in the form of a patient interface, e.g., a nasalrespiratory mask 10, according to a first embodiment of the invention.Mask 10 includes a rigidplastic mask shell 12 that has aperipheral flange 14 for mounting acushion 11 to the shell 12 (seeFIG. 17 ). Thecushion 11 abuts the wearer's face in use and is well known in the art. Theflange 14 includesslots 15 for the connection of mask restraining straps (not shown) that extend around the head of the wearer to maintain themask 10 adjacent the wearer's face. The straps are also known in the art. Theshell 12 also includes anarm 16 which terminates in a fitting 18 adapted to connect to a forehead support (not shown), which is also known in the art. - The
mask shell 12 includes abreathable gas inlet 20, e.g., in the form of a swivel elbow that is rotatably mounted to theshell 12. Theinlet 20 has afirst end 22 adapted for connection with a breathable gas supply conduit (not shown) coupled to a gas generator for supplying gas under pressure.Inlet 20 has asecond end 24, which is adapted to connect to and communicate the supplied pressurized gas to the interior of theshell 12 for subsequent communication with the wearer's airway.Mask 10 also includes a gas washout vent including anopening 26 in theshell 12 across which extends porous portion in the form of a thin airpermeable membrane 28, e.g., in the form of a porous disk or insert. Alternatively, the porous portion may take the form of a plastic portion, a porous sintered plastic, a textile and/or a plastic lined with a textile. The porous portion may be made of plastic material, e.g., polyethylene and/or polypropylene), and it may have a granular structure or a surface structure (e.g., smooth, rough, etc., on one or more surfaces or sides), and the porosity may be in the range of 120-220 μm. Depending on the thickness the porous portion may also serve as a filter. -
FIG. 2 discloses a similar nasalrespiratory mask 40, wherein like reference numerals are used to describe like parts as in the first embodiment ofFIG. 1 . Thus, themask 40 has ashell 12 with agas inlet 20. Instead ofslots 15 of the embodiment ofFIG. 1 , the mask shell includesopenings 42 forming part of abracket 43, which is adapted to snap engage with connection fittings (not shown) provided on the end of mask restraining straps (also not shown). Instead of thearm 16 and fitting 18, themask 40 includes an adjustable forehead support mechanism, indicated generally by thereference numeral 44. As inFIG. 1 ,mask 40 also includes a vent including anopening 26 formed in the gas inlet across which extends a thinpermeable membrane 28. While these and other forms of masks are well known, the two forms specifically disclosed herein are representative of the various known forms of masks and the washout vent described below may be utilized in any one or more of those or other known masks. - Referring to
FIG. 3 , there is illustrated an example of awashout vent 48 according to an aspect of the present invention which includes amembrane 50 interposed between anouter mask element 52 and aninner mask element 54. Themembrane 50 is essentially clamped between the two elements. Theelements openings membrane 50 spans across the registeringopenings - In
FIG. 4 , there is illustrated another way of mounting themembrane 50, similarly as inFIG. 3 , spanning theopening 56 of anouter mask element 52. In this embodiment themembrane 50 is secured solely to the inner surface of theouter element 52 and is not clamped between the two elements. - In
FIG. 5 , themask shell 12 has anopening 57, which receives aremovable holder 59.Holder 59 is preferably hollow and cylindrical and is releasably retained in theopening 57. Theholder 59 includes aninterior membrane 60 spanning the orifice throughholder 59. Agrid 62 is carried byholder 59 outwardly of themembrane 60 for protecting themembrane 60. It will be appreciated that thevarious membranes FIGS. 1-5 are representative only of various configurations and constructions of membranes for the vents for respiratory masks in general and that the membranes as discussed in more detail below have applicability to various other masks having vents for venting gas, particularly humidified gas, from respiratory masks. - Vent—Hydrophobic and/or Hydrophilic Materials
- In an aspect of the present invention, the membranes illustrated in
FIGS. 1-5 are preferably formed of or coated with a hydrophobic material. Alternatively, the membranes could be treated with surface affecting processes, e.g., nano treatment, coating, etc., similar to concrete treatment. A surface formed of or otherwise having hydrophobic properties of hydrophobic material repels moisture and water droplets. Consequently, if the vent surfaces or the entry to the vent surfaces are formed of hydrophobic material, the surfaces will resist moisture build up through the gas pathways of the vent as well as at the entry to the vent. The surfaces repel the moisture or water droplets and encourage the moisture or water droplets to run off the contacted hydrophobic surfaces. The hydrophobic material may be porous portion in the form of a porous plastic material and formed from such porous plastics as polyethylene, polypropylene, PVDF and PTFE. These materials naturally resist water entry into their pores. These materials are preferably sintered to form the porous construction. Alternatively, the material may be derived from a reticulated or cellular/matrix structure creating one or a plurality of small tortuous paths for gas. - There are many different forms of vent constructions and configurations. In certain vent configurations, the formation of the membrane of, or providing a vent coated with hydrophobic material, will cause a moisture droplet to sit higher off the vent surface. This may increase its proximity to the opposite vent surface tending to block the vent pathway. In those situations, vents formed of or coated with a hydrophilic material are beneficial. The formation of the vent or coating or otherwise treating or providing the vent with a hydrophilic material reduces the tendency of the moisture to remain within and block the vent pathway. As the moisture approaches the exit of the vent, the hydrophilic surfaces wick away the moisture thereby reducing blockage of the vent gas flow. Alternatively or in addition, the hydrophilic surface simply allows the air to pass because the droplet has a low profile.
- For example,
FIG. 5 a shows a vent hole 50.5 having a diameter defined by an inner surface that is formed or treated with a hydrophobic material, whileFIG. 5 b shows a similar vent hole 50.6 provided or treated with a hydrophilic material. Each vent hole 50.5, 50.6 is approximately the same size, yet the water droplet inFIG. 5 a tends to more fully occlude the vent hole as compared to the relatively more open vent hole inFIG. 5 b. - Various combinations of materials may be used to achieve the desired effect. For example, as shown in
FIG. 5 c , the vent hole 56.1 may have a cross-section having a composite or laminate construction, e.g., including two or more layers, such as a hydrophilic layer 56.2 and a hydrophobic layer 56.3.FIG. 5 d shows a relatively thin porous portion having a thickness of around 1-2 mm, in the form of a membrane 50.1 that is thinner than the adjacent wall/frame structure 52.1 supporting the porous portion.FIG. 5 e shows a relatively thick porous portion having a thickness of 1 to 20 mm and preferably 3 to 7 mm. The relatively thick porous portion is in the form of a porous disk (e.g., a depth filter 50.2—a filter that has some depth to it (not a thin filtration membrane)) that is thicker than the supporting frame/wall 52.2.FIG. 5 f is a cross-section of a porous portion in the form of a snap-fit plastic member 50.3 that is removable/attachable to a frame 52.3. - Another use of hydrophilic material, aside from the collection or channeling of moisture, is to prevent moisture from blocking and/or adversely affecting other parts or ports of the mask used to convey gas. For example, most masks include a pressure port or an O2 therapy port on the frame (e.g.,
frame 12 inFIG. 1 ) which can be fitted for formed with a hydrophilic material to prevent fouling of the port. This aspect and other aspects of the invention may be applied to any fluid (e.g., air) transmission orifice or orifices whereby control or management of moisture is desirable. - As with hydrophobic materials, the hydrophilic material may comprise a porous plastic material, such as hydrophilic polyethylene manufactured by Porex Corporation of Fairburn, Georgia. Other suitable material such Porex Porous Plastic and Oriented Fiber hydrophilic products can be designed to wick moisture and water droplets at different rates. See, for example, U.S. Pat. No. 6,638,610, issued Oct. 28, 2003, incorporated herein by reference. While “Porous Plastic” may be naturally hydrophobic, such material can be made hydrophilic if treated, e.g., with a surfactant.
- When using the Porex hydrophilic products, such as Porex Product XM1839PE (Polyethylene), the pore size may be 120-270 μm, preferably 170-220 μm, and the product may have a 5-35 mm diameter (e.g., about 20 mm) and a 1-10 mm thickness (e.g., about 5 mm). It has been found that these dimensions result in a balance of low noise and maintaining adequate flow even in humid conditions. The use of hydrophilic sintered plastic vents affords efficient airflow for CO2 removal while eliminating much of the vent flow noise associated with traditional venting methods. The vents are produced in plastic moldings preferably using a sintering process and may be molded into any geometry achievable by injection molding technology. The materials used in the mask and vent may be co-moldable and thereby facilitate or eliminate assembly issues. The
vent 26 may also be located in any pathway component of themask 10, such as theframe 12,elbow 20, cushion clip, forehead support, anti-asphyxia valve, cushion 11 or swivel, or air supply or venting pipes. SeeFIG. 17 . Further, the interface component, e.g., mask frame, can be manufactured from the stated materials, therefore providing a number of utilities or functions for components, thus potentially reducing the number of parts, which can result in ease of use and reduced manufacturing costs. For example, theentire frame 12 ofFIG. 1 or theelbow 20 ofFIG. 2 could be made of the stated materials. Moreover, the feature or component including the materials can be an add-on, molded-on, retrofit or completely integral. The hydrophilic porous plastic, such as the Porex Porous Plastics noted above, is advantageous in that it can be easily cleaned with a mildly abrasive cleanser to remove dirt, grease, smudges and the like. Heavy grease or oils may be removed with a solvent. - As illustrated in drawings
FIGS. 1 and 2 , the gas, e.g., air, passes through the sintered plastic hydrophobic or hydrophilic material such that the pressure difference between the inside of the mask or other piping and the atmosphere drives the gas through the fine pores of the material itself into the atmosphere. This has the effect of exhausting the air to atmosphere in a highly diffuse manner. Forcing the gas through the tiny tortuous paths in the sintered plastic material generates a high magnitude of viscous loss in the air. This causes the air to vent to atmosphere at very low velocity for a given bulk flow rate, and hence produces minimal noise. A generally higher surface area is required for vents of this type as compared with conventional venting orifices. The required area will depend greatly upon the porosity and thickness of the material used for the vent. Note that porous materials have been used previously for washout vents. See, for example, U.S. Pat. No. 6,581,594, as well as European Patent No. 0 697 225 A2 to Gottlieb et al. This European patent discloses a vent formed from a porous sintered material. However, the porosity and thickness of the vent for use in the present invention differs considerably from the Gottlieb et al. vent. Gottlieb et al. discloses a generally cylindrical insert, including a window, covered with a porous sintered material of approximately 3-4 mm thickness, but with a much finer porosity than set forth herein. The large pore size of the washout vent membranes herein also provide a flatter pressure flow curve, which is preferable to provide more vent flow at low pressures and less vent flow at high pressures. - Referring now to
FIGS. 6 a-6 c the vent membranes may be formed of a hydrophobic or hydrophilic material, which has variable porosity across the thickness of the membrane. Variable porosity in these materials may be achieved in the manufacturing process or by using a layer of material having a variable porosity. For example, as illustrated inFIG. 6 a , the hydrophobic or hydrophilic sintered porous plastic material forming themembrane 50 may have a fine pore size present at the entry to the vent and a larger pore size at the exit of the vent. The direction of the gas flow venting through themembrane 50 is represented by thearrow 70. InFIG. 6 a , the fine pore size is represented by thesmaller circles 72 within the membrane adjacent the gas entry surface of the membrane in contrast to the larger pore size represented by thecircles 74 adjacent the opposite gas exit surface of the membrane. InFIG. 6 b , the reverse configuration is illustrated. That is, the hydrophobic or hydrophilic sintered porous plastic material may have thecoarse pore size 74 at the entry surface of the vent and the finer pore size at the exit surface of the vent. A particular advantage of the use of a variable porosity material is that it enables a surface which is less likely to be blocked by moisture to be presented to highly humidified gas at the entry of the vent and a surface that is less likely to be blocked by dirt to reside at the exit of the mask where it may come into contact with dirt or grease. - Referring to
FIG. 6 c , variable porosity of the membrane may be achieved by layering materials of different porosities. For example, as illustrated inFIG. 6 c , the entry to the vent membrane represented by thesmall circles 72 may be formed of a hydrophobic or hydrophilic sintered plastic material having the fine pore size in afirst layer 76 on the entry side of the vent. Anexit 78 formed of a hydrophobic or hydrophilic sintered plastic material having a coarse pore size represented by thelarger circles 74 may be provided on the opposite side of the vent. Additionally, the interior layer may be formed of hydrophobic material covering or partly covering a hydrophilic layer which is at the exterior of the mask. With this construction, surface moisture tends to run off the vent with the hydrophilic layer encouraging humidified gas to flow through the vent. Alternatively, the hydrophilic material may constitute an interior layer at the entry to the vent, i.e., about the interior of the mask encouraging the humidified gas to flow through the vent. The exterior layer constituted by the hydrophobic material may encourage moisture, e.g., remnants of moisture from a prior washing of the vent, to run off the vent and mask and prevent blocking of the vent. - Referring to
FIG. 7 a , alayer 80 of either hydrophilic and/or hydrophobic porous material may be positioned prior to the gas entry to thevent 82. This inhibits build up of moisture at the entry of the vent. In the case of hydrophobic material, theinterior layer 80 may only be partial, e.g., donut shaped or annular, thus allowing humidified gas to pass unfiltered through an opening in the center of the layer, or other openings thereof, but still preventing the build up of moisture about the entry to the vent. Thevent 82 may be formed of conventional vent material, such as sintered metal or may be formed of the hydrophobic or hydrophilic material. The material may also be structured to increase the surface area within a smaller overall size vent. Increased surface area may be implemented using pleats, etc. - In
FIG. 7 b , alayer 86 of hydrophilic or hydrophobic porous material is positioned adjacent the exit side of thevent 88. In both cases using the hydrophobic or hydrophilic materials tends to flow moisture away from the vent openings. - The embodiments of
FIGS. 7 a and 7 b include a washout vent structure mounted on a selectively removable holder similar to that shown inFIG. 5 . However, the vent could also be mounted directly on the frame (or along another portion of the gas delivery path), e.g., as described in U.S. Pat. Nos. 6,561,190 and 6,561,191, incorporated herein by reference in its entirety). - Further, the embodiments of
FIGS. 7 a and 7 b may include a moisture collection area, e.g., in the form of a trough or channel that may be placed in the vicinity of the opening of the frame. In the example illustrated, the trough is in front of the opening, but it could also be positioned on the inside of the frame. - Referring to
FIG. 8 a , there is illustrated a further form of vent disclosed more particularly in U.S. Patent Application Ser. No. 60/643,114, filed Jan. 12, 2005, incorporated herein by reference in its entirety. As described and illustrated in that application one of the preferred vents comprises a generallyU-shaped passage 90.Vent 90 and optionally the overall mask frame where the vent is situated may be formed of the porous, sintered plastic hydrophobic and/or hydrophilic materials described herein. The surfaces of thevent passage 90 may have a roughened finish. InFIG. 8 b , the left side of the drawing figure illustrates ventpassages 92 which are continuous and smooth, albeit the walls of the passages undulate. The masks are made of molded polycarbonate, and may even have a small degree of roughness. In the right side ofFIG. 8 b , the walls of thepassages 94 are illustrated as having highly roughened surfaces (e.g., like the roughened surfaces which are generated using rapid prototype components (Objet®/SLA)—component made from a rapid prototyping process using stereolithography which deposits consecutive fine layers of plastic material according to input from a 3-D CAD model. Roughened surfaces of hydrophobic or hydrophilic material are particularly desirable as the vents produce reduced noise. The roughness can be quantified in terms of the ratio of the thickness of the roughened portion in relation to the overall height (or diameter) (H) of the orifice, as shown inFIG. 8 c . The roughness (R) should be in the range of H/50<R<H/2, and preferably H/10<R<H/5. Thus, if H is 0.7 mm, the roughness R will be between about 0.07 mm and 0.14 mm. In the example ofFIG. 8 c , an exemplary roughness of H/20 is shown in one region and a preferred roughness of H/5 is shown in another region. The dimension is defined as the height difference between the trough and the apex of the asperity. Thus, by molding vent components out of a plastic material, a roughened surface finish (like that shown on the right side ofFIG. 8 b ) can be utilized as a noise reduction mechanism, while the properties of the hydrophobic or hydrophilic materials assist in moisture management, e.g., to wick moisture and/or to maintain the vent orifices open thereby minimizing risk of blockage with moisture. - Membrane with Holes
- Further, use of non-porous hydrophobic or hydrophilic material, specifically plastic, which contains a number of venting holes (e.g., through holes) each having a diameter of up to 0.8 mm may be utilized. This provides a low noise solution, which will not significantly block humidified gas. Alternatively, the vent may be formed from non-hydrophilic or non-hydrophobic material and later coated with hydrophilic or hydrophobic material. The preferred arrangement is similar to that described in the stainless steel embodiment of U.S. Pat. No. 6,581,594, where the holes are smaller than 0.2 mm in diameter. In a further preferred embodiment (similar to the stainless steel embodiment provided in U.S. Pat. No. 6,581,594), the vent has a thickness of approximately 0.45 mm and a number of holes, each hole having a diameter of approximately 0.1 mm. The total open area of such a stainless steel membrane is approximately 5%. However, the vent geometry may take the form of any tapered or non-tapered vent geometry that is known in the art with a hydrophilic or hydrophobic coating enhancing the use of the vent with humidified air.
- In a further embodiment, a laminated textile may be used to provide the vent so that the vent has self-wicking capability. For example, in
FIG. 9 a , aplastic vent 100 containingsmall holes 102 may be provided as a low noise solution vent surrounded by a cotton basedmaterial 104 that has a capillary action. Thus, thecotton material 104 surrounding thevent 100 wicks the water from the vent. The wicking action may be along a direction D that is transverse to the axis of the holes 102.1, as shown inFIG. 9 c . and can be directed towards an adjacent membrane or part of the same membrane. Alternatively and inFIG. 9 b , atextile 110, such as cotton, may be applied as a protective layer in front of thevent 112. The protective layer captures the moisture and acts to wick the moisture away from the vent, while the flow passes through the protective layer and through the small holes in the low noise vent. As well as providing a mechanism for maintaining flow under humidified conditions, an extension of this mechanism is to wick the moisture away to a membrane where it can be subsequently exposed to the breathing gas flow, therefore acting as a humidifier for the breathing gas. - Further, a heated textile or conductive yarn with a current supplied to it (e.g. SoftSwitch as disclosed by Canesis Ltd) can surround the plastic vent or each individual vent hole. The textile prevents condensation of the humidified gas due to the raised temperature of the vent surface. The heated textile may also continue into the air path, e.g., into the mask frame, to increase the exposed area and increase humidity of the breathing gas and/or temperature, especially desirable in cooler climates.
- Wicking can be accomplished using a yarn material stitched together closely to allow moisture to capillate between yarns or it may also be at the fiber level, wherein each yarn is capable of capillary action.
- The textile fabric that holds moisture can have a dual utility in that the trapped moisture may be rebreathed to assist with moisturizing and/or humidifying the breathing air.
- Another way to control the flow through a porous vent under humidification is to draw the moisture away from the vent area using capillary action as will now be described. A
mask frame 140 includes avent assembly 142. Thevent assembly 142 has apatient side 144 and an outside 146. Theframe 140 includes anorifice 141 having a generally conical shape, with the narrow end of the vent on thepatient side 144 of the mask. This will allow more area for the moisture to move to when absorbed.Porous material 148 is arranged within theorifice 141 and extending to the outside of the frame. An additionalporous layer 149 would be on the outside of the frame. This extra area would act as a sponge drawing water away from the vent and helping control the vent flow. SeeFIG. 14 . - Using various pore sizes throughout the vent, the path of the moisture can be controlled. Moisture will more readily condensate onto/into materials with a larger surface area.
- Another embodiment of the vent of
FIG. 14 is shown inFIG. 15 . This embodiment involves acore 150 of less porous material surrounded by a more porous outer layer. The more porous area would act as a wick for the moisture to move through. An outer layer on the mask would also be required for moisture dissipation. SeeFIG. 15 - Another embodiment of the above would have
multiple layers 160 of porous material that would absorb moisture at different rates. SeeFIG. 16 . Initial condensation will occur on the layer that is on the patient side of the vent. The moisture will then be attracted into the layers above and out to the outer surface of the mask. - Referring to
FIG. 10 , there is illustrated a graph of flow rate through the vent versus pressure using a sintered polyethylene hydrophilic vent before and four hours after humidification. As illustrated in this graph, even with humidified air, the flow rate does not decrease substantially and decreases no more than 15% at any pressure. The flow rate is safe even at low pressures, with and without humidity. - In
FIG. 11 there is a similar graph comparing vent flow before humidification and vent flow after four hours of humidification with a sintered porous vent constructed in accordance with the Gottlieb European patent previously identified. This graph illustrates very low flow (potentially unsafe CO2 washout) even without humidity. With humidity, the flow is dangerously low. - In
FIG. 12 , the graph indicates the percentage decrease in flow rate at various pressures for the Gottlieb sintered porous vent as compared with a sintered polyethylene hydrophilic vent hereof, the performance of which is set forth inFIG. 10 . The graph ofFIG. 12 demonstrates the decrease in flow rate utilizing the hydrophilic vent structure of an embodiment of the present invention (designated “PE”) in comparison with the Gottlieb vent designated “WM”. At the desirable low pressures, it will be appreciated that the decrease in flow rate of the present invention is advantageously considerably less than the decrease in flow rate of the Gottlieb vent. The vent designated as “PE” provided adequate flow for CO2 washout, even at lower treatment pressures—both without and with humidity. Gottlieb (“WM”) flow falls to below safe levels when humidity is passed through the vent. This vent also takes a considerable amount of time to clear and recover from humidity blockage. - As illustrated in
FIG. 5 , an outer protective layer orplate 62 may be provided outside thevent membrane 60 and may comprise a coarse mesh or bars which protects the membrane from damage from large contaminants and handling. Alternatively, the protective plate or mesh may be eliminated if the vent is recessed within the mask frame or within theremovable holder 58. - An end-of-life indicator may be mounted on or adjacent to the vent to alert the user to the need to replace the vent. The indicator may provide an indication of the elapsed time that the vent has been in use, blockage of the vent due to humidity or blockage of the vent due to contamination or reduced vent flow rate. The indicator may be either visual or audible. For example, the indicator may include a water soluble dye that gradually washes away, similar to wear indicators provided in some tooth brushes.
- To compensate the hydrophilic nature of the porous vent, a variable vent can be implemented to compensate the flow reduction.
- In this form of the invention, a layer of
porous material 130 is mounted onfeet 132 in a slottedhole 134. Thefeet 132 are made of a hydrophilic material that expands when moist. This expansion lifts theporous material 130 out of the hole creating a vent in the gap between the frame and vent. SeeFIG. 13 a . Crimping the edge of the hole could reduces noise through variable vent. - As the humid air condenses in the vent, it will also be condensing in the feet. In a preferred form the flow reduction in the vent equals the flow increase created by the expanding feet.
- When the feet dry out (release moisture), they will shrink, reducing flow through the variable vent see
FIG. 13 b . In a preferred form the reduction in flow of the variable vent equals the increase in flow through the porous vent as it dries out. - In another form the variable vent is used in conjunction with a traditional vent. Instead of a porous vent being attached to the feet, a nonporous material is used. The flow increase of the variable vent counteracts the flow decrease caused by humidification at the traditional vent.
- While the invention has been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Also, the various embodiments described above may be implemented in conjunction with other embodiments, e.g., aspects of one embodiment may be combined with aspects of another embodiment to realize yet other embodiments. In addition, while the invention has particular application to patients who suffer from OSA, it is to be appreciated that patients who suffer from other illnesses (e.g., congestive heart failure, diabetes, morbid obesity, stroke, barriatric surgery, etc.) can derive benefit from the above teachings. Moreover, the above teachings have applicability with patients and non-patients alike in non-medical applications.
Claims (22)
1. (canceled)
2. A vent assembly configured to discharge gas washout from a patient interface that is configured to receive a pressurized flow of breathable gas from a positive airway pressure device, the vent assembly comprising:
a vent base configured to be attached to the patient interface and comprising a plurality of coplanar openings; and
a hydrophilic material positioned adjacent to the coplanar openings,
wherein the hydrophilic material is configured to wick water near the plurality of coplanar openings and/or capture moisture from a gas washout flow adjacent to the plurality of coplanar openings, and
wherein the hydrophilic material is configured to release the accumulated moisture and/or water to the pressurized flow of breathable gas for breathing by the patient when the patient inhales.
3. The vent assembly of claim 2 , wherein the hydrophilic material is configured to wick moisture away from the plurality of coplanar openings in a direction that is transverse to a direction of airflow through the vent assembly.
4. The vent assembly of claim 2 , wherein the hydrophilic material is configured to be between a patient and the plurality of coplanar openings in use.
5. The vent assembly of claim 2 , wherein the hydrophilic material is a textile.
6. The vent assembly of claim 2 , wherein the vent base is made of plastic.
7. The vent assembly of claim 2 , wherein the hydrophilic material is positioned so that gas washout flows through the hydrophilic material before flowing through the plurality of coplanar openings.
8. The vent assembly of claim 2 , wherein the hydrophilic material is configured to be between a patient and the plurality of coplanar openings in use,
wherein the hydrophilic material is a textile,
wherein the vent base is made of plastic, and
wherein the hydrophilic material is positioned so that gas washout flows through the hydrophilic material before flowing through the plurality of coplanar openings.
9. A patient interface assembly configured to receive a pressurized flow of breathable gas from a positive airway pressure device, the patient interface comprising:
a cushion configured to sealingly engage a patient's face;
a shell with an opening configured to receive the pressurized flow of breathable gas and discharge gas washout; and
the vent assembly of claim 2 ,
wherein the vent assembly is configured to be attached to the shell adjacent to the opening in the shell.
10. The patient interface assembly of claim 9 , wherein the vent assembly is removable from the shell.
11. The patient interface assembly of claim 9 , further comprising an air delivery tube connector configured to be attached to the shell.
12. A vent assembly configured to discharge gas washout from a patient interface that is configured to receive a pressurized flow of breathable gas from a positive airway pressure device by way of an air delivery tube, the vent assembly comprising:
a vent base configured to be attached to an air delivery tube connector that is configured to connect the air delivery tube to the patient interface, the vent base comprising a plurality of coplanar air passages; and
a hydrophilic material positioned adjacent to the coplanar air passages so that gas washout flowing from the patient interface flows through the hydrophilic material and the plurality of coplanar air passages, in use,
wherein the hydrophilic material is configured to wick water near the plurality of coplanar air passages and/or capture moisture from the gas washout adjacent to the plurality of coplanar air passages, and
wherein the hydrophilic material is configured to release the accumulated moisture and/or water to the pressurized flow of breathable gas for breathing by the patient when the patient inhales.
13. The vent assembly of claim 12 , wherein the hydrophilic material is positioned so that some of the gas washout bypasses the hydrophilic material before flowing through the plurality of coplanar air passages in use.
14. The vent assembly of claim 12 , wherein the hydrophilic material is configured to wick moisture away from the plurality of coplanar air passages in a direction that is transverse to a direction of airflow through the vent assembly.
15. The vent assembly of claim 12 , wherein the hydrophilic material is configured to be between a patient and the plurality of coplanar air passages in use.
16. The vent assembly of claim 12 , wherein the hydrophilic material is a textile.
17. The vent assembly of claim 12 , wherein the vent base is made of plastic.
18. The vent assembly of claim 12 , wherein the hydrophilic material is positioned so that gas washout flows through the hydrophilic material before flowing through the plurality of coplanar air passages.
19. The vent assembly of claim 12 , wherein the hydrophilic material is configured to be between a patient and the plurality of coplanar air passages in use,
wherein the hydrophilic material is a textile,
wherein the vent base is made of plastic, and
wherein the hydrophilic material is positioned so that gas washout flows through the hydrophilic material before flowing through the plurality of coplanar air passages.
20. A patient interface assembly configured to receive a pressurized flow of breathable gas from a positive airway pressure device, the patient interface comprising:
a cushion configured to sealingly engage a patient's face;
a shell with an opening configured to receive the pressurized flow of breathable gas and discharge gas washout; and
the vent assembly of claim 12 ,
wherein the vent assembly is configured to be attached to the shell adjacent to the opening in the shell.
21. The patient interface assembly of claim 20 , wherein the vent assembly is removable from the shell.
22. The patient interface assembly of claim 20 , further comprising an air delivery tube connector configured to be attached to the shell.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US18/361,651 US20240017030A1 (en) | 2005-07-29 | 2023-07-28 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
Applications Claiming Priority (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US70345605P | 2005-07-29 | 2005-07-29 | |
PCT/AU2006/001081 WO2007012145A1 (en) | 2005-07-29 | 2006-07-31 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US98854108A | 2008-01-10 | 2008-01-10 | |
US15/629,115 US20170281893A1 (en) | 2005-07-29 | 2017-06-21 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US16/918,432 US11752291B2 (en) | 2005-07-29 | 2020-07-01 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US18/361,651 US20240017030A1 (en) | 2005-07-29 | 2023-07-28 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US16/918,432 Continuation US11752291B2 (en) | 2005-07-29 | 2020-07-01 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
Publications (1)
Publication Number | Publication Date |
---|---|
US20240017030A1 true US20240017030A1 (en) | 2024-01-18 |
Family
ID=37682931
Family Applications (4)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/988,541 Active 2034-10-30 US9717870B2 (en) | 2005-07-29 | 2006-07-31 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US15/629,115 Abandoned US20170281893A1 (en) | 2005-07-29 | 2017-06-21 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US16/918,432 Active 2028-02-02 US11752291B2 (en) | 2005-07-29 | 2020-07-01 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US18/361,651 Pending US20240017030A1 (en) | 2005-07-29 | 2023-07-28 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
Family Applications Before (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/988,541 Active 2034-10-30 US9717870B2 (en) | 2005-07-29 | 2006-07-31 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US15/629,115 Abandoned US20170281893A1 (en) | 2005-07-29 | 2017-06-21 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US16/918,432 Active 2028-02-02 US11752291B2 (en) | 2005-07-29 | 2020-07-01 | Method and apparatus for managing moisture buildup in pressurised breathing systems |
Country Status (3)
Country | Link |
---|---|
US (4) | US9717870B2 (en) |
EP (2) | EP2537549B1 (en) |
WO (2) | WO2007012140A1 (en) |
Families Citing this family (57)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007012140A1 (en) | 2005-07-29 | 2007-02-01 | Resmed Limited | Method and apparatus for managing moisture buildup in pressurised breathing systems |
US20090151729A1 (en) | 2005-11-08 | 2009-06-18 | Resmed Limited | Nasal Assembly |
EP1981455B1 (en) * | 2006-01-20 | 2015-08-19 | Smith Optics, Inc. | Thermal goggle lens assembly with externally vented chamber |
US9254370B2 (en) | 2006-11-14 | 2016-02-09 | Resmed Limited | Frame and vent assembly for mask assembly |
US9119933B2 (en) | 2007-08-14 | 2015-09-01 | Plastiflex Group | Respiratory system |
US8397727B2 (en) | 2007-08-24 | 2013-03-19 | Resmed Limited | Mask vent |
WO2010080709A1 (en) | 2009-01-08 | 2010-07-15 | Hancock Medical | Self-contained, intermittent positive airway pressure systems and methods for treating sleep apnea, snoring, and other respiratory disorders |
EP2295105A1 (en) * | 2009-08-06 | 2011-03-16 | Air Liquide Medical Systems | Respiratory nasal mask with an oxygen port protected by a mobile flap |
US20120055471A1 (en) * | 2010-09-05 | 2012-03-08 | Slp Ltd. | Valve accessory for aiding speech during non-invasive respiratory therapy |
USD695887S1 (en) * | 2010-09-10 | 2013-12-17 | Resmed Limited | Respiratory mask |
US9339623B2 (en) | 2010-10-22 | 2016-05-17 | Koninklijke Philips N.V. | Exhaust gas assembly for a patient interface device |
WO2012052906A1 (en) * | 2010-10-22 | 2012-04-26 | Koninklijke Philips Electronics N.V. | Fluid coupling conduit with exhaust gas noise reduction |
US8336546B2 (en) | 2011-02-08 | 2012-12-25 | Hancock Medical, Inc. | Positive airway pressure system with head control |
WO2013001438A1 (en) | 2011-06-30 | 2013-01-03 | Koninklijke Philips Electronics N.V. | Skin-contact product having moisture and microclimate control |
US9827351B2 (en) | 2011-06-30 | 2017-11-28 | Koninklijke Philips N.V. | Medical and non-medical devices made from hydrophilic rubber materials |
WO2013001487A1 (en) | 2011-06-30 | 2013-01-03 | Koninklijke Philips Electronics N.V. | Water -absorbing elastomeric material |
NZ729631A (en) * | 2011-09-13 | 2018-09-28 | ResMed Pty Ltd | Vent arrangement for respiratory mask |
BR112014020260A8 (en) * | 2012-02-16 | 2017-07-11 | Capnia Inc | GAS DISTRIBUTOR WITH NASAL DIFFUSION PIECE |
CN104245028B (en) * | 2012-02-24 | 2017-03-08 | 皇家飞利浦有限公司 | Solidifying rain protection for the respiratory therapy for including humidification |
WO2013144753A1 (en) * | 2012-03-27 | 2013-10-03 | Koninklijke Philips N.V. | User interface device providing for improved cooling of the skin |
JP6276752B2 (en) * | 2012-04-20 | 2018-02-07 | コーニンクレッカ フィリップス エヌ ヴェKoninklijke Philips N.V. | Gas carrying headgear with porous boundary membrane |
EP2863975B1 (en) * | 2012-06-25 | 2018-11-28 | Fisher & Paykel Healthcare Limited | Medical components with microstructures for humidification and condensate management |
AU2015264928B2 (en) * | 2012-07-27 | 2017-03-23 | ResMed Pty Ltd | Patient Interface and Method for Making Same |
US9974915B2 (en) | 2012-07-27 | 2018-05-22 | Resmed Limited | Elastic headgear |
US9889267B2 (en) * | 2012-07-27 | 2018-02-13 | Resmed Limited | Patient interface |
NZ760681A (en) | 2013-01-16 | 2021-07-30 | ResMed Pty Ltd | Patient interface and method for making same |
US10314989B2 (en) | 2013-01-28 | 2019-06-11 | Hancock Medical, Inc. | Position control devices and methods for use with positive airway pressure systems |
WO2014129913A1 (en) * | 2013-02-21 | 2014-08-28 | Fisher & Paykel Healthcare Limited | Patient interface with venting |
EP3613456B1 (en) * | 2013-03-04 | 2024-04-24 | Fisher & Paykel Healthcare Limited | Patient interfaces with condensation reducing or compensating arrangements |
EP3909633B1 (en) | 2013-03-14 | 2023-11-22 | Fisher & Paykel Healthcare Limited | Humidification chamber with a mixing element comprising microstructures |
US20160015916A1 (en) * | 2013-03-15 | 2016-01-21 | Hancock Medical, Inc. | Positive airway pressure systems |
USD737953S1 (en) | 2013-07-26 | 2015-09-01 | Resmed Limited | Patient interface |
USD743535S1 (en) | 2013-07-26 | 2015-11-17 | Resmed Limited | Headgear for patient interface |
CA2919449C (en) | 2013-08-05 | 2022-04-12 | Fisher & Paykel Healthcare Limited | Seal for a patient interface, interface assemblies and aspects thereof |
US10471230B2 (en) * | 2013-10-11 | 2019-11-12 | Fisher & Paykel Healthcare Limited | HME and compact breathing apparatus |
NZ758876A (en) | 2013-11-15 | 2021-07-30 | ResMed Pty Ltd | Patient interface and method for making same |
JP6568520B2 (en) | 2013-12-02 | 2019-08-28 | コーニンクレッカ フィリップス エヌ ヴェKoninklijke Philips N.V. | Headgear with hydrophilic wicking material |
WO2015136489A1 (en) * | 2014-03-14 | 2015-09-17 | Fisher & Paykel Healthcare Limited | Humidification system |
WO2015170285A1 (en) | 2014-05-09 | 2015-11-12 | Fisher & Paykel Healthcare Limited | Diffuser arrangements for a vent of a respiratory interface |
EP3838324B1 (en) | 2014-06-17 | 2023-07-26 | Fisher & Paykel Healthcare Limited | Patient interfaces |
US10881829B2 (en) | 2014-08-18 | 2021-01-05 | Resmed Inc. | Portable pap device with humidification |
US10695527B2 (en) | 2014-09-18 | 2020-06-30 | ResMed Pty Ltd | Gas without vent for patient interface |
US10765824B2 (en) | 2015-01-30 | 2020-09-08 | ResMed Pty Ltd | Patient interface comprising a gas washout vent |
US10898668B2 (en) | 2015-03-04 | 2021-01-26 | ResMed Pty Ltd | Plastic to textile coupling for a patient interface and methods of manufacturing same |
USD776802S1 (en) | 2015-03-06 | 2017-01-17 | Hancock Medical, Inc. | Positive airway pressure system console |
EP4282457A3 (en) | 2015-07-20 | 2024-02-14 | Fisher & Paykel Healthcare Limited | Exhalation port |
EP3943138A1 (en) | 2015-09-04 | 2022-01-26 | Fisher & Paykel Healthcare Limited | Patient interfaces |
WO2017201419A1 (en) | 2016-05-19 | 2017-11-23 | Hancock Medical, Inc. | Positional obstructive sleep apnea detection system |
CN114887182A (en) | 2016-10-05 | 2022-08-12 | 费雪派克医疗保健有限公司 | Patient interface |
CN110573205B (en) * | 2016-11-07 | 2022-11-29 | 简易导气管公司 | Positive pressure ventilation mask and related apparatus, adapter and microphone |
CN114632241A (en) | 2016-11-11 | 2022-06-17 | 瑞思迈私人有限公司 | Gas washout vent for patient interface |
DE102017208421A1 (en) | 2017-05-18 | 2018-11-22 | Hamilton Medical Ag | Exhalation valve for a ventilator with noise reducing flow resistance |
USD884153S1 (en) | 2018-04-04 | 2020-05-12 | Fisher & Paykel Healthcare Limited | Frame for a mask assembly |
US20210228830A1 (en) * | 2018-06-04 | 2021-07-29 | Fisher & Paykel Healthcare Limited | Interface assemblies for respiratory therapy |
US11167096B2 (en) * | 2018-06-25 | 2021-11-09 | Conmed Corporation | Filter cartridge assemblies for managing fluid and humidity in endoscopic surgery |
EP4084847A4 (en) * | 2019-12-31 | 2024-03-06 | ResMed Asia Pte Ltd | A patient interface formed from a textile construction and including a stiffened portion to provide for customization |
CN116603183B (en) * | 2023-07-17 | 2023-09-12 | 山西萝兰环保科技有限公司 | Air purification equipment for interior decoration |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3099987A (en) * | 1961-03-07 | 1963-08-06 | Jr Roscoe G Bartlett | Respiratory apparatus |
US5042468A (en) * | 1989-02-13 | 1991-08-27 | Gibeck Respiration Ab | Breathing device |
US5595173A (en) * | 1995-06-29 | 1997-01-21 | Dodd, Jr.; Nevin W. | Rehumidification filter for ventilation mask |
US20020014241A1 (en) * | 2000-06-14 | 2002-02-07 | Gradon Lewis George | Nasal mask |
US20020096173A1 (en) * | 1991-12-20 | 2002-07-25 | Michael Berthon-Jones | Cpap respiratory apparatus |
US20030164170A1 (en) * | 2000-05-15 | 2003-09-04 | Joanne Drew | Respiratory mask having gas washout vent and gas washout vent assembly for respiratory mask |
US20050056286A1 (en) * | 2003-09-17 | 2005-03-17 | Huddart Brett John | Breathable respiratory mask |
Family Cites Families (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2807159C2 (en) * | 1978-02-20 | 1985-03-28 | Herding GmbH Entstaubungsanlagen, 8450 Amberg | Device for filtering solids from a flowable medium, in particular dust particles from atmospheric air |
US4770169A (en) * | 1987-02-13 | 1988-09-13 | Mdt Diagnostic Company | Anaesthetic mask |
US5443606A (en) * | 1992-03-26 | 1995-08-22 | The University Of Tennessee Reserch Corporation | Post-treatment of laminated nonwoven cellulosic fiber webs |
US5591510A (en) * | 1994-06-14 | 1997-01-07 | Tredegar Industries, Inc. | Layered fabric material having angled capillaries |
DE9411933U1 (en) | 1994-07-22 | 1994-10-27 | Weinmann G Geraete Med | Gas supply line |
CA2226485C (en) * | 1995-07-10 | 2002-09-10 | Japan Absorbent Technology Institute | Porous composite sheet and process for the production thereof |
DE29516589U1 (en) | 1995-08-31 | 1995-12-07 | Obligar Rizal | Cable clamp for batteries |
JP3780426B2 (en) * | 1996-07-17 | 2006-05-31 | 興研株式会社 | Dust mask with pressure fluctuation sensor |
AUPO504597A0 (en) | 1997-02-10 | 1997-03-06 | Resmed Limited | A mask and a vent assembly therefor |
US6561191B1 (en) * | 1997-02-10 | 2003-05-13 | Resmed Limited | Mask and a vent assembly therefor |
DE19757703C5 (en) * | 1997-12-23 | 2009-09-17 | Map Medizin-Technologie Gmbh | breathing device |
IL123122A0 (en) * | 1998-01-29 | 1998-09-24 | Oridion Medical Ltd | Oral/nasal cannula |
US6062220A (en) * | 1998-03-10 | 2000-05-16 | American Threshold Industries, Inc. | Reduced fogging absorbent core face mask |
US6638610B1 (en) * | 2000-03-06 | 2003-10-28 | Porex Technologies Corp. | Water and oil repellent porous materials and processes for making the same |
JP2003135612A (en) * | 2001-10-31 | 2003-05-13 | Hakugen:Kk | Filter for mask, and mask |
EP2319570A1 (en) | 2001-11-22 | 2011-05-11 | ResMed Limited | Respiratory mask and gas washout vent |
US7549316B2 (en) * | 2002-10-08 | 2009-06-23 | Ric Investments, Llc. | Integrated sample cell and filter and system using same |
JP2004261552A (en) * | 2003-03-03 | 2004-09-24 | Daihachi Matsuura | Steam mask |
US7559326B2 (en) * | 2003-06-18 | 2009-07-14 | Resmed Limited | Vent and/or diverter assembly for use in breathing apparatus |
NZ586864A (en) * | 2003-11-25 | 2012-04-27 | Resmed Ltd | Vent system for a mask that has selectable vents and a blower controller that senses which vent is selected |
JP2006122268A (en) | 2004-10-28 | 2006-05-18 | Ikumi Takasago | Protecting nose |
US8757150B2 (en) | 2004-12-17 | 2014-06-24 | Ric Investments, Llc | Condensation reduction and management systems in a gas flow delivery system |
US20100154798A1 (en) | 2004-12-30 | 2010-06-24 | Resmed Limited | Respiratory mask having gas washout vent and gas washout vent assembly for respiratory mask |
JP2008526394A (en) * | 2005-01-12 | 2008-07-24 | レスメド リミテッド | Respirator with gas escape vent and method of manufacturing the mask |
WO2007012140A1 (en) | 2005-07-29 | 2007-02-01 | Resmed Limited | Method and apparatus for managing moisture buildup in pressurised breathing systems |
-
2006
- 2006-07-28 WO PCT/AU2006/001071 patent/WO2007012140A1/en active Application Filing
- 2006-07-31 EP EP12178212.2A patent/EP2537549B1/en not_active Not-in-force
- 2006-07-31 EP EP06760938.8A patent/EP1912693B1/en not_active Not-in-force
- 2006-07-31 WO PCT/AU2006/001081 patent/WO2007012145A1/en active Application Filing
- 2006-07-31 US US11/988,541 patent/US9717870B2/en active Active
-
2017
- 2017-06-21 US US15/629,115 patent/US20170281893A1/en not_active Abandoned
-
2020
- 2020-07-01 US US16/918,432 patent/US11752291B2/en active Active
-
2023
- 2023-07-28 US US18/361,651 patent/US20240017030A1/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3099987A (en) * | 1961-03-07 | 1963-08-06 | Jr Roscoe G Bartlett | Respiratory apparatus |
US5042468A (en) * | 1989-02-13 | 1991-08-27 | Gibeck Respiration Ab | Breathing device |
US20020096173A1 (en) * | 1991-12-20 | 2002-07-25 | Michael Berthon-Jones | Cpap respiratory apparatus |
US5595173A (en) * | 1995-06-29 | 1997-01-21 | Dodd, Jr.; Nevin W. | Rehumidification filter for ventilation mask |
US20030164170A1 (en) * | 2000-05-15 | 2003-09-04 | Joanne Drew | Respiratory mask having gas washout vent and gas washout vent assembly for respiratory mask |
US20020014241A1 (en) * | 2000-06-14 | 2002-02-07 | Gradon Lewis George | Nasal mask |
US20050056286A1 (en) * | 2003-09-17 | 2005-03-17 | Huddart Brett John | Breathable respiratory mask |
Also Published As
Publication number | Publication date |
---|---|
US11752291B2 (en) | 2023-09-12 |
US20170281893A1 (en) | 2017-10-05 |
US9717870B2 (en) | 2017-08-01 |
EP2537549B1 (en) | 2017-04-05 |
EP2537549A1 (en) | 2012-12-26 |
WO2007012145A1 (en) | 2007-02-01 |
US20090044810A1 (en) | 2009-02-19 |
US20200338292A1 (en) | 2020-10-29 |
EP1912693B1 (en) | 2014-10-08 |
WO2007012140A1 (en) | 2007-02-01 |
EP1912693A4 (en) | 2010-03-31 |
EP1912693A1 (en) | 2008-04-23 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20240017030A1 (en) | Method and apparatus for managing moisture buildup in pressurised breathing systems | |
JP4987726B2 (en) | Respirator with a gas washout vent and a gas washout vent assembly for a respirator | |
US20160367782A1 (en) | Respiratory mask having gas washout vent and gas washout vent assembly for respiratory mask | |
US9878121B2 (en) | Ventilation mask with heat and moisture exchange device | |
JP6210950B2 (en) | Mask vent | |
US20180361094A1 (en) | Mask vent | |
JP4188883B2 (en) | Vent hole and vent assembly and mask assembly provided with the vent hole | |
EP2295103B1 (en) | Respiratory mask and gas washout vent | |
US9327092B2 (en) | Ventilation mask with integrated piloted exhalation valve | |
JP4354664B2 (en) | Respirator having a gas exhaust vent and gas exhaust vent assembly for a respiratory mask | |
JP5042789B2 (en) | Respirator having a gas exhaust vent and gas exhaust vent assembly for a respiratory mask | |
JP4607913B2 (en) | Respirator having a gas exhaust vent and gas exhaust vent assembly for a respiratory mask | |
JP7291805B2 (en) | Noise reduction equipment for respiratory devices |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: RESMED LIMITED, AUSTRALIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:VELISS, LEE JAMES;KWOK, PHILIP RODNEY;HENRY, ROBERT EDWARD;SIGNING DATES FROM 20090205 TO 20090211;REEL/FRAME:064426/0190 Owner name: RESMED PTY LTD, AUSTRALIA Free format text: CHANGE OF NAME AND CHANGE OF ADDRESS;ASSIGNOR:RESMED LIMITED;REEL/FRAME:064424/0644 Effective date: 20190301 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |