RESPIRATORY MASK

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35USC§119(e) of US provisional patent application 63/265,806 filed on December 21 , 2021 , the specification of which is hereby incorporated by reference.

TECHNICAL FIELD

[0001] The technical field relates generally to devices for filtering nasal breathing. More particularly, it relates to a filtering nasal cannula to be inserted in a user’s nostril and to a respiratory mask, such as a nasal mask, to be positioned to cover the user’s nose and/or mouth.

BACKGROUND

[0002] Airborne and indoor pollution is a major health problem worldwide. The presence of airborne viruses such as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), its mutant forms and the possible emergence of new viruses add a risk whose impact cannot be measured. The general population has now become aware of the importance of breathing clean air and consequently of the inconvenience of wearing masks and their limitations in providing continuous personal protection against the inhalation of airborne viruses. This has created a generalized sense of insecurity that has led to a legitimate need for practical and effective personal protection against air pollution, Coronavirus Disease (COVID) and other likely future pandemics.

[0003] According to the World Health Organization, over 90% of the world's population lives in a polluted environment, sometimes 24 hours a day. Depending on the source, air pollution causes between 7 and 8.8 million premature deaths per year worldwide.

[0004] The market for a personal, wearable filtration device is in the billions of dollars and growing. Face masks remain the most widely used defense against inhalation of deleterious particles despite their acknowledged problems with tightness and comfort. Companies selling half-face masks such as the FFP2 (Filtering Face Piece level 2) or N95 (filtering at least 95% of airborne particles) should warn users that their filtration devices are not designed for people with beards (leaks), children (stability) and people with cognitive delays. There are 33% of Americans and 55% of men worldwide who wear a beard and children are the most vulnerable to the effects of pollution. The need for personal, portable filtration is not being met for these categories of people.

[0005] Users who resign themselves to wearing a face mask do so despite recognized shortcomings: the mask is difficult to adjust and to remain tightly and effectively fitted to the face. To certify the effectiveness of a mask, it must pass a leak test, which is not simple, not always available and only really valid at the time of the test. A poorly fitting mask that allows unfiltered air to enter from around its periphery gives the user a false sense of security. On the other hand, properly fitted face masks generate negative pressure that must be developed under the mask in order to force ambient air through the filtering material; this negative pressure results in an increase in inspiratory effort.

[0006] For example, the FFP2 half-mask filter requires a negative pressure for inspiration that is between -2.5 and -4.5 cm H2O. The negative pressure for inspiration without a mask is around -1.5 cm H2O. This additional negative pressure requires an increased respiratory effort and causes a crushing effect on the nostrils which, in turn, exert a crushing effect on the internal nasal valve thus increasing the inspiratory effort following the decrease in the diameter of the air inlet. The metal tab on the upper part of the mask, which must be pressed against the bridge of the nose to minimize leaks, usually adds additional pressure on the internal nasal valve. This increased difficulty in breathing is also accentuated by the presence of dead space under the dome of a mask. This dead space of about 150 ml for a half-mask type N95 doubles the normal anatomical dead space for an adult male and causes a re-inspiration of CO2 that can reach 3%, i.e. , 75 times higher than in the ambient air. To eliminate this superfluous CO2, one has to increase one's respiratory rate or amplify one's tidal volume, which has the effect of increasing the negative pressure under the mask. An increased negative pressure under the mask further accentuates the crushing of the nostrils and, by the effect of entrainment, the narrowing of the lumen of the internal nasal valve, thus creating more resistance that must be overcome by breathing more vigorously.

[0007] This chain of effects can explain the feeling of oppression felt by many individuals under a mask and the reaction of individuals who exclaim when removing it how good it is to breathe freely. To compensate for these increased breathing difficulties the user often resorts to mouth breathing. Mouth breathing is associated with stress breathing, which increases the anxiety associated with wearing the mask and the fear of being contaminated by viruses. In addition to exposing us to our own breath on a continuous basis, mouth breathing deprives us of the recognized benefits of nasal breathing, including the release of nitric oxide, which promotes the uptake of O2 in the blood through its vasodilatory effect and acts as an antimicrobial and antiviral agent. Another problem often mentioned by people who have to wear vision or safety glasses is the fogging of the glasses. This is not a trivial matter as it can represent a real risk of accidents. This is because in order to obtain a functional seal of the mask on the face, we must ensure that the edge of the nose is in close contact with the upper part of the mask, which is the very place where the glasses rest on the nose. The glasses must then be lifted at the base (point of contact with the nose) to make room for the upper part of the mask, thus creating a bridge that allows the humid heat concentrated under the mask to rise naturally under the glasses and create that embarrassing fog. This humid heat, which can reach 54°C when the humidex is taken into account, becomes uncomfortable when put in contact with the face, causing frequent itching and an irresistible need to scratch, thus moving the mask. This excessive heating of the inspired air leads to blood congestion of the nasal turbinates, which accentuates nasal congestion, making nasal breathing more difficult. [0008] In addition, the inhalation of this hot and humid air disturbs the perception of the air intake by the nasal thermoreceptors, which contributes to aggravate the sensation of "lack of air". The mask also prevents access to the mouth and must be removed to drink, eat, relieve an itch, expectorate or to blow on an object such as sawdust. By removing or touching the mask repeatedly to reposition it on the nose, there is a high risk of contaminating your fingers with the outer wall of the mask, which is loaded with pathogens. Moreover, the mask hides a good part of the face and makes it difficult to express our good feelings (smiles) and prevents lip-reading for the hearing impaired. The mask is also unattractive and can cause rashes and the elastics can hurt the top of the ears after a while. For all these reasons, wearing a mask is not well tolerated, producing a feeling of oppression, which explains why it is taken off as soon as you think you are safe from pollution or airborne contaminants. A removed mask does not filter anymore, compromising its overall efficiency if we consider the quantity of particles and pathogens filtered during a 24-hour period. Furthermore, even when the mask is worn, there is often a poor fit to the face as soon as the mask is put on or as a result of head movements that create openings through which the inspired air passes first, choosing the path of least resistance. The decrease in inspiratory resistance experienced by the user can be more of a relief than a warning that the mask is not working properly. Face masks fail to provide continuous personal protection that can be guaranteed.

[0009] In view of the above, there is a need for a nasal filter cannula which would be able to overcome or at least minimize some of the above-discussed prior art concerns.

BRIEF SUMMARY

[0010] It is therefore an aim of the present disclosure to address the above- mentioned issues.

[0011] According to a first aspect, there is provided a nasal cannula comprising a cannula body having a peripheral wall made of an air impermeable material and extending between a proximal end and a distal end, and defining an air passageway extending between a proximal air port and a distal air port, the cannula body being frustoconical or cylindrical shaped and being insertable in a nostril of a user, with the proximal end positioned inside a nasal vestibule and the distal end positioned substantially adjacent to a nostril inlet; and a filter extending inside the air passageway and having a peripheral wall abutting against the peripheral wall of the cannula body, the filter being made of an air permeable material.

[0012] In some embodiment, the filter is mounted to an internal surface of the peripheral wall and extends from the proximal end of the cannula body towards the distal end thereof and covering entirely the proximal air port and the distal air port.

[0013] In some embodiment, the cannula body is made of a biocompatible and shape memory material.

[0014] In some embodiment, the filter is made of a biocompatible and shape memory material.

[0015] According to a second aspect, there is provided a nasal cannula comprising a cannula body including an air permeable peripheral wall extending from a distal end to a proximal end, the peripheral wall defining an air containing cavity with a proximal air port at the proximal end of the peripheral wall, the air containing cavity being closed at the proximal end by the air permeable peripheral wall, the air containing cavity being frustoconical or cylindrical shaped, said cannula body being insertable in a nostril of a user, with the proximal end of the peripheral wall being positioned inside a nasal vestibule and the distal end positioned substantially adjacent to a nostril inlet.

[0016] In some embodiment, the cannula body is made of a biocompatible and shape memory filtering material.

[0017] In some embodiment, the nasal cannula further comprises a breathable substance receiving receptacle mounted to the cannula body and extending downwardly from the distal end of the peripheral wall, the breathable substance receiving receptacle being opened towards the distal air port.

[0018] In some embodiment, the nasal cannula further comprises at least one mechanical connector mounted to the cannula body and adjacent to the distal end of the cannula body.

[0019] In some embodiment, the at least one mechanical connector comprises at least one of a Velcro™, a magnet, and a clip.

[0020] In some embodiment, there is provided an eyeglass kit comprising at least one of the nasal cannulas as described above, further comprising a pair of filtering eyeglasses having a frame with lower frame segments; and at least one external elbowshaped connector having a cannula connecting end engageable with the at least one mechanical connector of the nasal cannula and an opposed end securable to the lower frame segment of the pair of filtering eyeglasses.

[0021] In some embodiment, the at least one external elbow-shaped connector has an eyeglass connecting end engageable with the lower frame segments of the pair of filtering eyeglasses.

[0022] In some embodiment, each one of the lower frame segments is substantially C-shaped with a passageway extending therealong and configured to contain a filtering material.

[0023] In some embodiment, the at least one external elbow-shaped connector comprises a valve opening extending therethrough and a one-way valve covering the valve opening, the one-way valve being configured in an open configuration on exhalation and in a closed configuration during inhalation.

[0024] In some embodiment, the at least one nasal cannula comprises two nasal cannulas and the at least one external elbow-shaped connector comprises two external elbow-shaped connectors, with each one of the nasal cannulas being engageable with a respective one of the external elbow-shaped connectors. [0025] In some embodiment, there is provided a mustache kit comprising the nasal cannula as described above, further comprising a filtering material securable to the mechanical connector of the nasal cannula and extending horizontally between the nostril and an upper lip of the user, when the nasal cannula is worn.

[0026] In some embodiment, the filtering material extends outside of the nostril and covers at least partially an external surface of a user’s nose.

[0027] In some embodiment, the nasal cannula further comprises a dynamic valve operatively mounted to the internal surface of the peripheral wall of the cannula body between the proximal end and the distal end of the cannula body, for allowing an air flow through the cannula body during an inspiration phase and selectively restricting the air flow through the cannula body during an expiratory phase.

[0028] In some embodiment, the nasal cannula further comprises a protective grid, the protective grid extending from the peripheral wall of the cannula body and across the air passageway, the protective grid being located between the cannula proximal end and the dynamic valve.

[0029] In some embodiment, the nasal cannula further comprises a prehension tongue mounted to the cannula body and extending downwardly from the distal end of the peripheral wall to facilitate an extraction of the nasal cannula from the nostril.

[0030] According to a third aspect, there is provided a nasal cannula comprising a cannula body and a valve. The cannula body has a peripheral wall made of an air impermeable material and extending between a proximal end and a distal end and defining an air passageway extending between a proximal air port and a distal air port. The cannula body is dividable into an internal portion including the proximal air port, a valve-receiver portion including the distal air port, and a middle portion located between the internal portion and the valve-receiver portion, the middle portion comprises a bulge. The proximal portion is insertable in a user’s nostril with the proximal air port being located in a nasal vestibule of the user and the middle portion and the valve-receiver portion are located externally to the nasal vestibule. The valve is operatively mounted to an internal surface of the peripheral wall of the cannula body in the valve-receiver portion.

[0031] In some embodiment, the cannula body is made of a biocompatible and shape memory material.

[0032] In some embodiment, the valve comprises a dynamic valve, for allowing an airflow through the cannula body during an inspiration phase and selectively restricting the air flow through the cannula body during an expiratory phase.

[0033] In some embodiment, the nasal cannula further comprises a supplemental filter extending from the peripheral wall of the cannula body and across the air passageway in the valve-receiver portion, the supplemental filter being located between the middle portion and the valve.

[0034] According to a fourth aspect, there is provided a nasal mask assembly comprising two nasal cannulas as described above, each one being insertable in a respective one of two user’s nostrils, the two nasal cannulas being connected together; a cannula connector connecting the two nasal cannulas together; and a head mount securable to the two nasal cannulas.

[0035] According to a fifth aspect, there is provided a nasal mask assembly comprising a cannula body and at least one valve. The cannula body has peripheral wall made of an air impermeable material, the cannula body comprising two internal portions, each one defining a proximal air port, at least one valve-receiver portion defining a distal air port, and a middle portion located between the internal portions and the at least one valve-receiver portion and being in gas communication therewith. The at least one valve is operatively mounted to an internal surface of the peripheral wall of the cannula body and contained in the at least one valve-receiver portion.

[0036] In some embodiment, the middle portion comprises a bulge.

[0037] In some embodiment, the nasal mask assembly further comprises a head mount securable to the cannula body. [0038] In some embodiment, the cannula body is made of a biocompatible and shape memory material.

[0039] In some embodiment, the at least one valve comprises a dynamic valve, for allowing an air flow through the cannula body during an inspiration phase and selectively restricting the air flow through the cannula body during an expiratory phase.

[0040] In some embodiment, the at least one valve comprises a unidirectional valve, for allowing an incoming air flow through the cannula body during an inspiration phase and preventing an outcoming air flow out of the cannula body during an expiratory phase; and wherein the nasal mask assembly further comprises a pop-off valve mounted to the cannula body, allowing the outcoming air flow to escape from the cannula body when a pressure inside the cannula body is greater than a pressure threshold of the popup valve.

[0041] In some embodiment, the nasal mask assembly further comprises a connector plug connectable to a sensor to monitor at least one of a pressure, a temperature, a CO2 content and an O2 content.

[0042] In some embodiment, the nasal mask assembly further comprises at least one mechanical connector mounted to the cannula body and configured to extend over a user’s philtrum.

[0043] In some embodiment, the at least one valve-receiver portion comprises two valve-receiver portions, each one including a respective one of the distal air port and the at least one valve comprises two valves, each one being operatively mounted to the internal surface of the peripheral wall of the cannula body and contained in a respective one of the two valve-receiver portions, wherein the middle portion extends between the two internal portions and the two valve-receiver portions and is in gas communication therewith.

[0044] According to a sixth aspect, there is provided a respiratory nasal mask comprising a mask body including a triangularly shaped hollow shell made of an air impermeable material and configured to cover a user’s nose and define an internal breathing chamber; a cushion mounted to the mask body and extending along a peripheral edge thereof to form a seal between the mask body and a user’s face; a head mount mounted to the mask body and configured to maintain the mask body in contact with the user’s face; and two valves operatively mounted to the mask body and being substantially aligned with user’s nostrils.

[0045] In some embodiment, the mask body is made of a biocompatible and shape memory material.

[0046] In some embodiment, the head mount comprises at least three straps, each one being connected at one end to a vertex of the triangularly shaped hollow shell and at another end to a headgear.

[0047] In some embodiment, the valves comprise dynamic valves allowing an air flow through the mask body during an inspiration phase and selectively restricting the air flow through the mask body during an expiratory phase.

[0048] In some embodiment, each one of the valves comprises a unidirectional valve, for allowing an incoming air flow inside the internal breathing chamber during an inspiration phase and preventing an outcoming air flow out of the internal breathing chamber during an expiratory phase; and wherein the respiratory nasal mask further comprises a pop-off valve mounted to the mask body, allowing the outcoming air flow to escape from the internal breathing chamber when a pressure therein is greater than a pressure threshold of the pop-off valve.

[0049] In some embodiment, the respiratory nasal mask further comprises a connector plug, configured to connect a sensor to monitor at least a pressure, a temperature, a CO2 content and an O2 content, or any combination thereof.

[0050] According to a seventh aspect, there is provided a filtering nasal mask, comprising a mask body including a triangularly shaped hollow shell made of an air permeable material configured to cover a user’s nose and define an internal breathing chamber; and a head mount, comprising at least three straps, each one of the at least three straps having a first end connected to a vertex of the triangularly shaped hollow shell and a second end connected to a headgear.

[0051] In some embodiment, the mask body is made of a biocompatible and shape memory filtering material.

[0052] In some embodiment, the filtering nasal mask further comprises at least one mechanical connector mounted to a lower edge of the mask body and configured to extend over a user’s philtrum.

[0053] In some embodiment, the filtering nasal mask further comprises two valves operatively mounted to the mask body and being substantially aligned with user’s nostrils.

[0054] According to a eighth aspect, there is provided an respiratory mask comprising a mask body including a hollow shell made of an air impermeable material and configured to cover at least one of a user’s mouth and a user’s nose and define an internal breathing chamber; a head mount mounted to the mask body and configured to maintain the mask body in contact with a user’s face; two unidirectional valves operatively mounted to the mask body and located under and substantially aligned with user’s nostrils, wherein the unidirectional valves allow an incoming air flow in the internal breathing chamber during an inspiration phase and preventing an outcoming air flow out of the internal breathing chamber during an expiratory phase; and a pop-off valve in gas communication with the internal breathing chamber of the mask body and allowing the outcoming air flow to escape from the internal breathing chamber when a pressure inside the internal breathing chamber is greater than a pressure threshold of the pop-up valve.

[0055] In some embodiment, the respiratory mask further comprises a silencer tubing extending between the mask body and the pop-off valve.

[0056] In some embodiment, the respiratory mask further comprises a unidirectional valve mounted to the mask body and connecting the mask body and the silencer tubing, the unidirectional valve providing control gas communication between the internal breathing chamber and the silencer tubing, the unidirectional valve allowing the outcoming air flow out of the internal breathing chamber into the silencer tubing during the expiratory phase and preventing the incoming air flow from the silencer tubing in the internal breathing chamber during the inspiration phase.

[0057] In some embodiment, the silencer tubing further comprises a bulge defining an air chamber, the air chamber being filled with outcoming air flow during the expiratory phase.

[0058] In some embodiment, the mask body is made of a biocompatible and shape memory material.

[0059] In some embodiment, the respiratory mask further comprises a connector plug, configured to connect a sensor to monitor at least a pressure, a temperature, a CO2 content and an O2 content, or any combination thereof.

[0060] In some embodiment, the respiratory mask further comprises a CO2 capture device mounted to the silencer tubing, the CO2 capture device being in gas communication with the air chamber via a CO2 capture device port extending through the silencer tubing, the CO2 capture device being configured to capture an excess of CO2 from an airflow circulating in the air chamber.

[0061] In some embodiment, the hollow shell of the mask body is triangularly shape and covers the user’s nose and mouth to form an oronasal respiratory mask.

[0062] In some embodiment, the hollow shell of the mask body covers the user’s mouth to form a buccal respiratory mask.

[0063] In some embodiment, the respiratory mask further comprises at least one mechanical connector mounted to an upper edge of the mask body and configured to extend over a user’s philtrum. [0064] In some embodiment, there is provided an oronasal mask comprising a nasal mask as described above; and a respiratory mask as described above, wherein the at least one connector of the nasal mask is connectable to the at least one connector of the buccal respiratory mask.

BRIEF DESCRIPTION OF THE DRAWINGS

[0065] FIG. 1 is a schematic side elevation view of a user’s face, showing a nasal cannula inserted into a nasal vestibule of the user, in accordance with an embodiment.

[0066] FIG. 2 is a perspective view of the nasal cannula shown in FIG. 1 , in accordance with a first embodiment, wherein the nasal cannula includes a cannula body and a filter, with the filter extending inside an air passageway of the cannula body, from a proximal end of the cannula body to about half distance between the proximal end and a distal end.

[0067] FIG. 3 is a perspective view of the nasal cannula shown in FIG. 1 , in accordance with a second embodiment, wherein the nasal cannula includes a cannula body and a filter, with the filter extending inside an air passageway, entirely between a proximal end and a distal end of the cannula body.

[0068] FIG. 4 is a perspective view of the nasal cannula shown in FIG. 1 , in accordance with a third embodiment, wherein the nasal cannula includes a cannula body made of a filtering material.

[0069] FIG. 5 is a schematic side elevation view of the user’s nose, showing the nasal cannula of FIG. 3 or FIG. 4 inserted into the nasal vestibule of the user, with a filtering material extending outwardly of the nose, in accordance with an embodiment.

[0070] FIG. 6 is cross-sectional front elevation view of the user’s nose having two nasal cannulas of FIG. 5 inserted therein (one nasal cannula per nasal vestibule), in accordance with an embodiment. [0071] FIG. 7 is a cross-sectional side elevation view of the user’s nose, showing a nasal cannula inserted into the nasal vestibule of the user, wherein the nasal cannula also includes a breathable substance receiving receptacle, in accordance with an embodiment.

[0072] FIG. 8 is a front elevation view of an eyeglass kit, in accordance with an embodiment, mounted to a user’s face.

[0073] FIG. 9 is an enlarged view of a portion of the eyeglass kit of FIG. 8, including a pair of filtering glasses, two external elbow-shaped connectors connected to lower frame segments of the pair of filtering glasses, and two nasal cannulas connected to a respective one of the two external elbow-shaped connectors, in accordance with an embodiment.

[0074] FIG. 10 is an enlarged and exploded view of the eyeglass kit of FIG. 9.

[0075] FIG. 11 is a cross-sectional side elevation view of one of the lower frame segments of the eyeglass kit of FIG. 9, in accordance with an embodiment.

[0076] FIG. 12 is a schematic front elevation view of a mustache kit, in accordance with an embodiment, mounted to a user’s nose and lips.

[0077] FIG. 13 is a perspective view of the nasal cannula shown in FIG. 1 in accordance with another embodiment, wherein the nasal cannula includes a cannula body, a filter, and a dynamic valve.

[0078] FIG. 14 is a longitudinal cross-sectional view of a dynamic valve, shown in a collapsed configuration, in accordance with a first embodiment of the dynamic valve.

[0079] FIG. 15 is a perspective front view of the nasal cannula shown in FIG. 1 , wherein the nasal cannula includes a cannula body and a dynamic valve, in accordance with a second embodiment of the dynamic valve. [0080] FIG. 16 is a perspective front view of the nasal cannula shown in FIG. 1 , wherein the nasal cannula includes a cannula body and a dynamic valve, in accordance with a third embodiment of the dynamic valve, in a configuration where a mobile incomplete seat obstructs approximately 25% of a surface of a flap membrane.

[0081] FIG. 17 is the nasal cannula of FIG. 16, in a configuration where the mobile incomplete seat obstructs approximately 33% of the surface of the flap membrane.

[0082] FIG. 18 is the nasal cannula of FIG. 16, in a configuration where the mobile incomplete seat obstructs approximately 50% of the surface of the flap membrane.

[0083] FIG. 19 is a perspective view of a dynamic valve combined with a protective grid, in accordance with an embodiment.

[0084] FIG. 20 is a schematic side elevation view of the user’s nose, showing the nasal cannula shown in FIG. 1 inserted into the nasal vestibule of the user, further comprising a prehension tongue, in accordance with an embodiment.

[0085] FIG. 21 is a cross-section view of a user’s nose, showing a nasal cannula including a dynamic valve and inserted into the nasal vestibule of the user, in accordance with an embodiment.

[0086] FIG. 22 is a schematic cross-sectional view of a nasal mask assembly engaged with a user’s nose, in accordance with an embodiment, the nasal mask assembly includes two nasal cannulas of FIG. 21 connected together and inserted into a respective nasal vestibule of the user.

[0087] FIG. 23 is a perspective view of the nasal mask assembly of FIG. 22, engaged with the user’s face.

[0088] FIG. 24 is a schematic cross-sectional view of a nasal mask assembly engaged with a user’s nose, in accordance with an embodiment, wherein the two nasal cannulas are in gas communication. [0089] FIG. 25 is a perspective view of the nasal mask assembly of FIG. 24, engaged with the user’s face.

[0090] FIG. 26 is a schematic cross-sectional view of a nasal mask assembly of FIG. 24, in accordance with an embodiment, wherein the nasal mask assembly includes a pop-off valve.

[0091] FIG. 27 is a perspective view of the nasal mask assembly of FIG. 26, engaged with the user’s face.

[0092] FIG. 28 is a perspective view of a respiratory nasal mask including two dynamic valves, in accordance with an embodiment, and mounted to a user’s face.

[0093] FIG. 29 is a perspective view of a respiratory nasal mask, in accordance with another embodiment, mounted to a user’s face, wherein the respiratory nasal mask also includes a pop-off valve.

[0094] FIG. 30 is a perspective view of a filtering nasal mask covering a user’s nose, in accordance with an embodiment.

[0095] FIG. 31 is a perspective view of a filtering nasal mask, in accordance with another embodiment, covering a user’s nose and further including two one-way valves.

[0096] FIG. 32 is a perspective view of a filtering nasal mask, in accordance with still another embodiment, covering a user’s nose and partially covering user’s cheeks.

[0097] FIG. 33 is a front elevation view of an oronasal respiratory mask including a silencer tubing, in accordance with an embodiment, mounted to a user’s face.

[0098] FIG. 34 is a front elevation view of an oronasal respiratory mask, in accordance with another embodiment, mounted to a user’s face, wherein the oronasal respiratory mask comprises a bulge on the silencer tubing.

[0099] FIG. 35 is a front elevation view of a buccal mask in accordance with an embodiment, the buccal mask being connected to the nasal mask assembly of FIG. 25. [00100] It will be noted that throughout the appended drawings, like features are identified by like reference numerals.

DETAILED DESCRIPTION

[00101] Moreover, although the embodiments of the nasal cannula and corresponding parts thereof consist of certain geometrical configurations as explained and illustrated herein, not all of these components and geometries are essential and thus should not be taken in their restrictive sense. It is to be understood, as also apparent to a person skilled in the art, that other suitable components and cooperation thereinbetween, as well as other suitable geometrical configurations, may be used for the nasal cannula, as will be briefly explained herein and as can be easily inferred herefrom by a person skilled in the art. Moreover, it will be appreciated that positional descriptions such as “above”, “below”, “left”, “right” and the like should, unless otherwise indicated, be taken in the context of the figures and should not be considered limiting.

[00102] In the following description, the same numerical references refer to similar elements. Furthermore, for the sake of simplicity and clarity, namely so as to not unduly burden the figures with several references numbers, not all figures contain references to all the components and features, and references to some components and features may be found in only one figure, and components and features of the present disclosure which are illustrated in other figures can be easily inferred therefrom. The embodiments, geometrical configurations, materials mentioned and/or dimensions shown in the figures are optional and are given for exemplification purposes only.

[00103] Moreover, it will be appreciated that positional descriptions such as “above”, “below”, “forward”, “rearward” “left”, “right” and the like should, unless otherwise indicated, be taken in the context of the figures and correspond to the position and orientation of the nasal cannula and corresponding parts when being worn by a user. Positional descriptions should not be considered limiting. [00104] To provide a more concise description, some of the quantitative expressions given herein may be qualified with the term "about". It is understood that whether the term "about" is used explicitly or not, every quantity given herein is meant to refer to an actual given value, and it is also meant to refer to the approximation to such given value that would reasonably be inferred based on the ordinary skill in the art, including approximations due to the experimental and/or measurement conditions for such given value.

[00105] In the following description, the term “about” means within an acceptable error range for the particular value as determined by one of ordinary skill in the art, which will depend in part on how the value is measured or determined, i.e. , the limitations of the measurement system. It is commonly accepted that a 10% precision measure is acceptable and encompasses the term “about”.

[00106] In the above description, an embodiment is an example or implementation of the inventions. The various appearances of “one embodiment,” “an embodiment” or “some embodiments” do not necessarily all refer to the same embodiments.

[00107] Although various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment.

[00108] Reference in the specification to “some embodiments”, “an embodiment”, “one embodiment” or “other embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments, of the inventions.

[00109] It is to be understood that the phraseology and terminology employed herein is not to be construed as limiting and are for descriptive purpose only. [00110] The principles and uses of the teachings of the present invention may be better understood with reference to the accompanying description, figures and examples.

[00111] It is to be understood that the details set forth herein do not construe a limitation to an application of the invention.

[00112] Furthermore, it is to be understood that the invention can be carried out or practiced in various ways and that the invention can be implemented in embodiments other than the ones outlined in the description above.

[00113] It is to be understood that the terms “including”, “comprising”, “consisting” and grammatical variants thereof do not preclude the addition of one or more components, features, steps, or integers or groups thereof and that the terms are to be construed as specifying components, features, steps or integers.

[00114] If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional elements.

[00115] It is to be understood that where the claims or specification refer to “a” or “an” element, such reference is not be construed that there is only one of that element.

[00116] It is to be understood that where the specification states that a component, feature, structure, or characteristic “may”, “might”, “can” or “could” be included, that particular component, feature, structure, or characteristic is not required to be included.

[00117] The descriptions, examples and materials presented in the claims and the specification are not to be construed as limiting but rather as illustrative only.

[00118] Meanings of technical and scientific terms used herein are to be commonly understood as by one of ordinary skill in the art to which the invention belongs, unless otherwise defined.

[00119] The present invention may be implemented in the testing or practice with methods and materials equivalent or similar to those described herein. [00120] Referring to the drawings and more particularly to figure 1 , there is shown an embodiment of a nasal cannula (10) insertable in a nostril of a nose (2) of a user. The nasal cannula (10) comprises a proximal end (22), a distal end (24), and a peripheral wall (26) extending between the proximal end (22) and the distal end (24). Once inserted in the nostril, the proximal end (22) is positioned inside a nasal vestibule (6) and the distal end is positioned substantially adjacent to a nostril inlet (5). The diameter of an internal nasal valve of the nose being 2 to 3 times smaller than the diameter of the nasal vestibule (6), the nasal cannula (10) is prevented from being aspirated into the airways even after enlargement of this internal nasal valve by the expanding cannula. The flexibility of the nasal cannula (10) decreases the risk of injury to nasal tissue should the nose be impacted while the nasal cannula (10) is in place in the nasal vestibule (6). One nasal cannula (10) can be inserted into each one of the nasal vestibules (6) where it is almost imperceptible once in place. The inner walls of the nasal vestibule (6) are made of epithelium and are therefore not hypersensitive to touch. By inserting the nasal cannula (10) into the nasal vestibule (6), the vibrissae or nasal hairs are immobilized on the walls, which prevents the feared tickling and does not cause sneezing.

[00121] Figure 2 shows a first embodiment of the nasal cannula (10), comprising a cannula body (20) made of an air impermeable material, and a filter (50) made of an air-permeable material. The cannula body (20) is substantially tubular and has a peripheral wall (26) extending between the proximal end (22) and the distal end (24). Being tubular in shape, the cannula body (20) defines an air passageway (32) extending between a proximal air port (34) and a distal air port (36). The filter (50) is located and extends inside the air passageway (32). The filter has a peripheral wall abutting against the peripheral wall (26) of the canula body (20), substantially adjacent to the proximal end (22), and covering entirely the proximal air port (34). As shown in figure 2, the filter (50) extends approximately on half of the peripheral wall (26), such that approximately the first half of the air passageway, substantially adjacent to the proximal end, is filled with filter (50). [00122] The cannula body (20) can be made of a biocompatible material. This material can meet or exceed the ISO 10993 standard for contact with intact skin for less than 24 hours. Medical grade silicone is an example of a suitable material. The cannula body (20) can be frustoconical or cylindrical shaped and hollowed out. The distal end (24) can be flared. The cannula body (20) can be approximately between 0.4 cm to 2 cm long, for example about 1 cm long (between the distal end (24) and the proximal end (22)); and approximately between about 0.4 cm and about 1 .5 cm of internal diameter, for example the diameter of the air passageway is about 1 cm for an adult. The material of the cannula body (20) can be flexible enough to be compressed with the fingers but has sufficient shape memory so that once inserted into the nasal vestibule, the cannula body (20) can expand again after a few seconds. In other words, the cannula body (20) can be made of a resilient material. This expansion must be significant enough to push the vibrissae to the sides and enlarge the air passage, especially at the level of the internal nasal valve by lateral traction on the adjacent tissues.

[00123] The distal end (24) of the cannula body (20) can be dark-colored to improve aesthetics or brightly colored to demonstrate to others that the user is wearing respiratory protection in accordance with health requirements. This difference in cannula color can also be used by the user to determine the direction of insertion of the nasal cannula (10).

[00124] This enlargement of the air passage can promote a decrease in inspiratory resistance which is normally around -1.5 cm H2O. According to Poiseuille's law, each reduction, however small, in the diameter of the air inlet of the nose has an impact that is expressed as the square of its size. For example, a 50% reduction in air inlet diameter corresponds to a 16-fold increase in resistance. This deleterious effect is particularly important for infants and premature babies who are struggling with bronchial embarrassment. Therefore, enlarging the air passage of the internal nasal valve and spreading the nasal vibrissae, wearing the nasal cannula (10) can result in nasal inspiration that is easier than during normal inspiration. [00125] As the cannula body (20) expands, the cannula body can be able to adapt to different nasal configurations by making contact at several points on the walls of the nasal vestibule (6), which promotes its tightness and anchoring in the nasal vestibule, even during forced breathing. To ensure the pressure on the walls of the nasal vestibule (6) remains comfortable for the user, the nasal cannula (10) can be available in different sizes. It is also possible that the cannula body (20) be user’s specific. For instance, the cannula body (20) can be designed based on a scan of the user’s nasal vestibule (6) and made by a custom impression of the cannula body (20), for instance with a 3D printer.

[00126] The external surface (30) of the peripheral wall (26) of the cannula body (20) can be smooth and soft to the touch or with a gripping material with the angle of the grips facing the distal end (24) so that the nasal cannula (10) can be easily inserted into the nasal vestibule but extracted only with some resistance to improve its stability in the nasal vestibule. The external surface (30) of the peripheral wall (26) of the cannula body (20) can be hydrophobic to prevent possible nasal discharge from impairing the effectiveness of the filter.

[00127] The filter (50) is made of a filtering and air permeable material. The filter (50) can be mounted to an internal surface (28) of the peripheral wall (26) of the cannula body (20), substantially adjacent to the proximal end (22) of the cannula body (20). The filter (50) is abutting to the internal surface (28) of the peripheral wall (26) of the cannula body (20) in such a way as to prevent any intrusion of inspired air between the filter (50) and the internal surface (28) of the peripheral wall (26). The filter (50) can have a certain shape memory that allows the filter (50) to anchor itself in the cannula body (20) despite a nasal exhalation of about 100 L/min. In some embodiment, there is no need for anchoring other than the pressure that the filter (50) exerts on the internal surface (28) of the peripheral wall (26) of the cannula body (20). Furthermore, a frustoconical cannula body (20) can ensure that the filter (50) is not drawn into the air passage of the internal nasal valve. In another embodiment, a biocompatible adhesive such as silicone can also be used to secure the filter (50) along and around the internal surface (28) of the peripheral wall (26) of the cannula body (20) to prevent air intrusion between the filter (50) and the cannula body (20). With the cannula body (20), the filter (50) can be compressed prior to insertion into the nasal vestibule (6) and will expand as much as the expansion of the cannula body (20) is allowed within the nasal vestibule (6). It is also possible to use a filter with sufficient shape memory to expand or help expand the cannula body after compression with the fingers.

[00128] In some embodiments, the filter (50) can be replaceable, i.e. , the used filter can be detached from the cannula body (20) and replaced with a new or disinfected filter (50). The new or disinfected filter (50) can be compressed out of a package or compressible with the fingers, and can be inserted into the cannula body (20) in order to change only the filter (50), as needed.

[00129] Referring to figure 3, there is shown a second embodiment of the nasal cannula wherein the features are numbered with reference numerals in the 100 series which correspond to the reference numerals of the previous embodiment.

[00130] In the second embodiment of the nasal cannula (110), as shown in figure 3, the nasal cannula (110) comprises a cannula body (120) made of an air impermeable material, and a filter (150) made of an air-permeable material. In such embodiment, the filter (150) extends on the entirety of the peripheral wall (126), such that the entirety of the air passageway (132) is filled with filter (50). In other words, the filter (150) abuts against the the internal surface (128) of the peripheral wall (126) of the cannula body (120), from about the distal end (124) to about the proximal end (122).

[00131] Referring to figure 4, there is shown a third embodiment of the nasal cannula wherein the features are numbered with reference numerals in the 200 series which correspond to the reference numerals of the previous embodiment.

[00132] In the third embodiment of the nasal cannula (210), as shown in figure 4, the cannula body is made of a filtering material. In such embodiment, the cannula body (220) includes an air permeable peripheral wall (226) made of the filtering material, extending from the open distal end (224) to the closed proximal end (222), also made of the filtering material. Therefore, the filtering material of the cannula body (220) defines an air containing cavity (238), free of filtering material. The nasal cannula (210) can be frustoconical or cylindrical shaped or bell-shaped.

[00133] This embodiment of the nasal cannula (210) can be presented as a cartridge and can be directly introduced into the nasal vestibule (6) after being compressed. A shape memory (or resilience) allows the filtering material of the cannula body (220) once introduced into the nasal vestibule (6) to resume its expansion after a few seconds. This expansion should be significant enough to increase the airflow, especially through the internal nasal valve, and to push the vibrissae to the sides. This filtering material of the cannula body (120) should resist rupture when, in order to remove it from the nasal vestibule, it is pinched with the fingers and pulled outwards.

[00134] In some embodiment, as shown in figures 5 and 6, the peripheral wall (126, 226) of the nasal cannula (110, 210) as shown in the second and third embodiment of the nasal cannula, extends from the distal end (124, 224) outside of the nostril, forming an external filtering material (152) that can be folded over the nostrils and up onto an external surface of the nose (3) where it can be retained by the elastic property of the external filtering material (152) or in any other way. If more stability is desired, an elastic band connected to this external filtering material (152) and passed behind the head can allow for better stabilization of this "nose cover". The nose thus covered with the external filtering material (152) is designed to recover heat and humidity from exhalation and can provide inhaled air with increased temperature and humidity to counteract the cold, dry winter air known to accentuate nasal discharge and bronchial irritation. This external filtering material (152) can be of various colors or patterns.

[00135] In first, second and third embodiments (figures 2 to 4), as well as in the embodiment described in figures 5 and 6, the filtering material can be made of a biocompatible, antibacterial, flexible material. For example, the filtering material can be composed of nonwoven nanofibers of the order of 300 nanometers obtained by electrospinning a polymer solution which offer little resistance to the passage of air, and which have a filtration capacity of particles of 0.3 microns of 95% and more. [00136] The filtering material can also be composed of nanofibers or any other biocompatible High Efficiency Particulate Air (HEPA) material that meets the filtration criteria (>99% for bacteria and > 95% for 0.3 micron particles) and resistance to the passage of inspired airflow (< 343 pa) and exhaled airflow (< 245 pa) at a flow rate of 85 L/min as required by the National Institute for Occupational Safety and Health (NIOSH) code 42CFR84 for N95 face masks. The material may or may not be antibacterial and electrostatically charged.

[00137] In some embodiment, the filtering material can have properties that allow it to retain some of the heat and moisture from the exhaled gases and release it to the subsequent inhaled gases. The partial pressure of exhaled CO2 (40 mm Hg) being much higher than the partial pressure of the atmosphere (0.3 mm Hg), the CO2 can diffuse very quickly into the atmosphere before being re-breathed. This property can have a direct impact on the decrease of nasal mucus production when exposed to cold temperatures.

[00138] In some embodiment, the filtering material can be white or light colored with a dark distal end to improve aesthetics or be brightly colored to demonstrate to others that they are wearing respiratory protection in accordance with the required health measures. This difference in color of the filtering material can also be used by the user to determine the direction of insertion of the nasal cannula.

[00139] In some embodiment, the filtering material can be enclosed in a hydrophobic, woven or nonwoven, soft touch fabric.

[00140] In an embodiment, the filtering material can be a washable textile with high-performance filtration. For instance, and without being limitative, a filtration media such as the one disclosed in WO2021/212219 can be used.

[00141] For sake of clarity, the following optional embodiments can be adapted on the first embodiment as described in figure 2, as well as on the second and third embodiment, as described respectively in figures 3 and 4. [00142] In some embodiment, as shown in figure 7, the nasal cannula (10) may further comprise a breathable substance receiving receptacle (64) mounted to the cannula body (20) and extending downwardly from the distal end (24) of the cannula body (20). The breathable substance receiving receptacle (64) can be made of similar material as the cannula body (20). The breathable substance receiving receptacle (64) is slightly recessed from the main air stream of the nose (2), for example in the soft tissue triangle section (7) of the nose (2). For instance, and without being limitative, the breathable substance receiving receptacle (64) can be triangular shaped, with a stopper at its distal end, the length of which can be cut according to the length of the nose (2) so that it rests comfortably in the soft tissue triangle section (7) of the nose (2). The breathable substance receiving receptacle (64) is open towards the distal air port (36) of the nasal cannula (10). A perforated flexible container (65) can be contained in the breathable substance receiving receptacle (64). The perforated flexible container (65) can be selectively configured in an open configuration to fill it with volatile substances and a closed configuration. These volatile substances can be in solid or liquid form impregnating an absorbent material held in the perforated flexible container (65). In some embodiment (not shown), when the nasal cannula (110) is as per the second and third embodiments as described in figures 3 and 4, the breathable substance receiving receptacle (64) can be replaced by a nest embedded in the filtering material. The nest is a recess in the internal surface (128) of the peripheral wall (126) of the cannula body (120), substantially adjacent to the distal end (124), where the perforated flexible container (65) can be inserted. In some embodiment, the perforated flexible container (65) can be embedded in the filtering material. Under the influence of heat and/or humidity from the exhaled gases, the active substances contained in the perforated flexible container (65) release active molecules into the inspired air without offering significant resistance to the inspiratory effort. These molecules are released at the rate of breathing, thus matching a variation in metabolism associated with the level of activity. These molecules can be, but are not limited to medicinal substances, perfumes, odor neutralizers, disinfectants, energizers etc. [00143] Figures 8 to 11 show an eyeglass kit (70). The eyeglass kit (70) includes a pair of filtering eyeglasses (75), two external elbow-shaped connectors (71 ), and two nasal cannulas (10). The nasal cannulas (10) can be any one of the nasal cannulas disclosed herein, shown in the figures, or alternative thereof. The pair of filtering eyeglasses (75) can further comprise a frame with two lower frame segments (76). The components of the eyeglass kit (70) on each side of the pair of filtering eyeglasses (75) are similar. Therefore, to ease the description in the following paragraphs, only one will be described.

[00144] In the embodiment shown, the lower frame segments (76) are part of the eyeglasses frame. In another embodiment (not shown), the two lower frame segments (76) can be distinct components securable to the eyeglasses frame. In the embodiment shown in figure 8, the lower frame segment (76) is substantially C-shaped and has an end adjacent to the user’s nose. In an embodiment, the lower frame segment (76) is substantially C-shaped to define a passageway (77) extending therealong as shown in figure 11. It is appreciated that the shape of the lower frame segment (76) and its passageway (77) can vary from the embodiment shown.

[00145] The external elbow-shaped connector (71 ) is securable at one end to the lower frame segment (76) and, more particularly, to the end adjacent to the nose, and to a respective one of the nasal cannulas (10) at the opposite end. Thus, the external elbowshaped connector (71 ) extends between an eyeglass connecting end (73) and a cannula connecting end (72).

[00146] The eyeglass connecting end (73) of the external elbow-shaped connector (71 ) can be connected to the lower frame segment (76) by an eyeglasses’ frame mechanical connector, such as and without being limitative a Velcro™, a magnet, and a clip. In an embodiment, the mechanical connection between the external elbowshaped connector (71 ) and the lower frame segment (76) is detachable in a manner such that the elbow-shaped connector (71 ) can be detached from the eyeglass frame without removing the nasal cannula (10) inserted in the nasal vestibule. [00147] The cannula connecting end (72) of the external elbow-shaped connector (71 ) also includes a mechanical connector, such as and without being limitative Velcro™, a magnet, and a clip. To be engageable with the nasal cannula (10), the latter also includes a complementary mechanical connector (39) adjacent to the distal end (24) of the cannula body. As for the mechanical connector of the cannula connecting end (72), the complementary mechanical connector (39) of the cannula (10) can be a Velcro™, a magnet, and a clip, for instance.

[00148] In some embodiments, the eyeglass kit (70) can further comprise a replaceable filtering material (78) contained in the lower frame segment (76) and/or in the external elbow-shaped connector (71 ). In the non-limitative embodiment shown in Figure 9, both the lower frame segment (76) and the external elbow-shaped connector (71 ) contains replaceable filtering material (78). For the lower frame segment (76), the filtering material (78) is contained in the passageway (77). In some implementations, the quantity of filtering material contained in the passageway (77) of the lower frame segment (76) is greater than the quantity contained in the nasal cannula (10). To easily remove and replace the replaceable filtering material (78) from the passageway (77) of the lower frame segment (76), the replaceable filtering material (78) can slightly protrude outwardly of the passageway (77). Therefore, the filtering material (78) can be pinched and pull outwards of the lower frame segment (76). To insert a new replaceable filtering material (78), the passageway (77) of the lower frame segment (76) can be filled by pushing the replaceable filtering material (78) presented in the form of a hem.

[00149] Referring now to figures 9 and 10, in some embodiments, the eyeglass kit (70) can also include a one-way valve (74) or non-return valve, located inside an internal passageway of the external elbow-shaped connector (71 ). More particularly, a valve opening (not shown, covered by the one-way valve (74)) can be defined in the external elbow-shaped connector (71 ). The one-way valve (74) is mounted to the external elbowshaped connector (71 ) and covers the valve opening with a surface area of the one-way valve (74) being greater than a surface area of the valve opening. The one-way valve (74) can be configured in an open configuration to allow direct exhalation under the nostrils to minimize partial rebreathing of CO2, and in a closed configuration to force inspired air to pass through the replaceable filtering material (78) contained in the lower frame segment (76) of the eyeglasses and/or the filtering material contained in the external elbow-shaped connector (71 ). As such, on an inhalation of the user, the inspired air is directed through the replaceable filter material (78) contained in the lower frame segment (76), then through the external elbow-shaped connector (71 ) (and its filtering material, if any) and through the filtering material of the nasal cannula (10).

[00150] In an embodiment, the one-way valve (74) includes a flexible membrane made of a biocompatible and resilient I shape memory material, such as and without being limitative silicone or neoprene. The membrane can be substantially circular in shaped and maintained inside the external elbow-shaped connector (71 ) by a valve anchor, connected on one side to an internal surface of the external elbow-shaped connector (71 ) and on the other side to a middle (79) of the membrane. In the closed configuration of the one-way valve (74), a peripheral surface of the membrane is superposed against an external surface of the external elbow-shaped connector (71 ), thereby ensuring that no external air can flow inside the external elbow-shaped connector (71 ). The one-way valve (74) prevents air infiltration inside the external elbow-shaped connector (71 ) during inspiration. The one-way valve (74) can be configured in the open configuration during expiration when a positive pressure established during expiration is sufficient to lift the one-way valve (74), i.e., to create a space between the membrane and the external surface of the external elbow-shaped connector (71 ). The membrane automatically returns to the closed configuration once the pressure inside the external elbow-shaped connector (71 ) is reduced.

[00151] Figure 12 shows an embodiment of a mustache kit (80) including two nasal cannulas (10) and a filtering material (81 ) superposable to the user’s face, under the nose. As for the eyeglass kit (70), the nasal cannulas (10) can be any one of the nasal cannulas disclosed herein, shown in the figures, or alternative thereof. Furthermore, each one of the nasal cannulas (10) also include a mechanical connector (39) mounted to the cannula body (20). The filtering material (81 ) of the mustache kit (80) is substantially planar, i. e. , 2D. The filtering material (81 ) of the mustache kit (80) is engageable with the mechanical connector (39) of the nasal cannula (10) to be maintained under the user’s nose. In an embodiment, the filtering material (81 ) of the mustache kit (80) can include a mechanical connector engageable with the mechanical connector (39) of the nasal canula (10). In an embodiment, the mechanical connectors of the nasal canula (10) and the mustache kit (80) can include, for instance, a Velcro™, a magnet, and a clip. When the filtering material (81 ) of the mustache kit (80) is engaged with the mechanical connectors (39) of the nasal cannulas (10), the filtering material (81 ) extend externally of and below the user’s nose. It is appreciated that the thickness of the external substantially 2-D filter (81 ) can vary between the approximate thickness of a paper sheet and a thickness of 2 cm. The external substantially 2-D filter (81 ) extends horizontally between the nostril inlet and an upper lip (1 ) of the user. In an embodiment, the external substantially 2-D filter (81 ) is rigid enough to hold this filtering material above the upper lip (1 ) like a mustache, in order to increase the surface and the efficiency of the filtration. The external substantially 2-D filter (81 ) can be dark or flesh color or the like and can be of a different composition than the filtering material of the nasal cannula (10). This external substantially 2-D filter (81 ) represents an additional filtration area that can be added as needed depending on the level of pollution or contaminants in the environment, thus providing more than one level of personal protection. The needs can vary from home to the street, from the street to work and from work to leisure.

[00152] In some embodiment, as shown in figure 13, the nasal cannula (10) can be equipped with a dynamic valve (500) or other mechanism that can allow for significantly increased resistance-free inhalation compared to normal (between 0.1 and -2 cm H2O) and increased expiratory resistance compared to normal (between 1 and 30 cm H2O) or more likely between 3 and 10 cm H2O. The dynamic valve (500) is located in the cannula body (20) and, more particularly, in the air passageway (32) through which the inspiratory and expiratory airflow passes. The dynamic valve (500) is operatively mounted to the internal surface (28) of the peripheral wall (26) of the cannula body (20), between the proximal end (22) and the distal end (24) of the cannula body (20), between the distal end (24) and the filter (50). In the embodiment shown, the dynamic valve (500) includes a support (550) and a flap membrane (540) mounted to the support (550), as it will be described in further details below.

[00153] When the nasal cannula (10) contains the dynamic valve (500), the filter (50) is located in the cannula (20) at a sufficient distance from the dynamic valve (500), so as not to interfere with the movement of the flap membrane (540) of the valve.

[00154] In an embodiment, the support (550) is substantially rigid and comprises a plurality of spokes extending through the air passageway (32), perpendicular to a longitudinal axis of the nasal cannula body (20), i.e. , an axis extending between the distal end (24) and the proximal end (22), and having ends mounted to the internal surface (28) of the peripheral wall (26). The spokes are spaced-apart from one another to allow an airflow therethrough. It is appreciated that the number and the configuration of the spokes can vary.

[00155] The flap membrane (540) is made of a flexible material and, being dynamic, it is configurable in a collapsed configuration and an expanded configuration with the inspiration/expiration cycle. The flap membrane (540) is configured in the collapsed configuration during inspiration, shown schematically in figure 13, wherein a periphery thereof is displaced towards a center of the air passageway (32), towards the proximal end (22). During expiration, the flap membrane (540) is configured in the expanded configuration wherein it extends substantially normal to the longitudinal axis of the nasal cannula body (20). More particularly, in the expanded configuration, it abuts against the spokes of the support (550), and it partially obstructs the airflow in the air passageway (32).

[00156] In an embodiment, the flap membrane (540) can be perforated centrally to be attached to the support (550), as will be described in more details below.

[00157] In some embodiment, increased inspiratory and expiratory pressures for respiratory exercise purposes can be adjusted respectively by an inverted dynamic inspiratory valve i.e., which produces a resistance to air flow mainly on inspiration (example from -2 cm to -50 cm H2O) and by a dynamic expiratory valve which produces a resistance to air flow mainly on expiration (example from +3 cm to +50 cm H2O). These breathing resistances can be modified by adjusting the mechanism of each of the dynamic valves used. Optionally, a removable filtering material, proximal to both valves, can prevent the aspiration of valves or spare parts in case of rupture. The distance between the proximal valve and the filter material and between the two valves should be sufficient to allow free play of the valves.

[00158] Referring to figure 14, there is shown a first alternative embodiment of the dynamic valve wherein the features are numbered with reference numerals in the 500 series. In figure 14, the flap membrane (540) is represented in the collapsed configuration, wherein it is shaped substantially as a segment of a sphere with its concavity facing the proximal end (22) of the nasal cannula (10). The support (550) comprises an anchoring system (560) located in the center of the support (550) and to which the flap membrane (540) is mounted. The anchoring system (560) comprises a stem and a head and extends through the central perforation of the flap membrane (540) with the head being located closer to the proximal end (22) and the stem, closer to the distal end (24). Thus, during inspiration, the flap membrane (540) is configured in the collapsed configuration (as shown in figure 14) to let the inspiratory air flow through the air passageway (32) without adding significant effort. During exhalation, this flap membrane (540) is pushed back towards the support (550) and simultaneously configured in the expanded configuration (not shown), and the pressure rises rapidly upstream, i.e., closer to the proximal end (22). The pressure that can be reached will vary in accordance with the rigidity of the flap membrane and the spacing between the spokes; this is the peak pressure, which can be between 0.1 cm H2O and 100 cm H2O and in certain implementations between 2 cm H2O and 50 cm H2O. Above this pressure, the flap membrane (540) bends just enough to let the exhalation escape between the spokes of the distal support (550). As soon as the expiratory airflow decreases, the flap membrane, which is shaped memory, can start its expansion and can maintain a relatively stable pressure in the airways.

[00159] Before the expiratory airflow ceases, the flap membrane (540) returns in the expanded configuration, thus maintaining a Positive End-Expiratory Pressure (PEEP) in the airways, which can be between 1 cm H2O and 50 cm H2O and in some embodiments between 2 cm H2O and 20 cm H2O.

[00160] Referring to figure 15, there is shown a second alternative embodiment of the dynamic valve wherein the features are numbered with reference numerals in the 600 series which correspond to the reference numerals of the first embodiment of the dynamic valve.

[00161] In figure 15, the dynamic valve (600) comprises the flap membrane (640) located in the air passageway (32) of the cannula body (20) and is mounted to the support (650). This flap membrane (640) represented in the expanded configuration in figure 15, abuts against the spokes of the support (650). The support (650) comprises an anchoring system (660) located in the center of the support (650) and to which the flap membrane (640) is mounted. As for the above-described embodiment, the anchoring system (660) comprises a stem and a head and extends through the central perforation of the flap membrane (640) with the head being located closer to the proximal end and the stem, closer to the distal end of the cannula body (20).

[00162] In some embodiment, the support (650) further comprises a fixed incomplete seat (670) that protrudes inwardly from a portion of a circumference of the support (650) about 2 to 3 mm inside the cannula body (20). The support (650) further comprises a mobile incomplete seat (680) that also protrudes inwardly from a portion of the circumference of the support (650) about 2 to 3 mm inside the cannula body (20), on a different plan than the fixed incomplete seat (670), i.e. slightly spaced-apart from one another along the longitudinal axis of the nasal cannula body (20), such that the mobile incomplete seat (680) can overlay partially or entirely the fixed incomplete seat (670). The mobile incomplete seat (680) is rotatable about the longitudinal axis, between a superposed configuration and a juxtaposed configuration. In the superposed configuration, the mobile incomplete seat (680) overlays entirely the fixed incomplete seat (670) (or is aligned with along the longitudinal axis), and in the juxtaposed configuration, the mobile incomplete seat (680) overlays a negligible portion of the fixed incomplete seat (670), such as the fixed incomplete seat (670) and the mobile incomplete seat (680) are substantially juxtaposed.

[00163] During inspiration, this lightweight flap membrane (640) folds back in the collapsed configuration to allow the inspiratory airflow to pass through without adding significant effort. On exhalation, this flap membrane (640) is pushed back against the distal support (650) and the fixed (670) and mobile (680) incomplete seats. The pressure then rises rapidly upstream, i.e., closer to the proximal end (22), to a level determined by the stiffness of the flap membrane (640), the spacing between the spokes of the distal support (650) and the length of the fixed and mobile incomplete seats (670 and 680). The resulting peak pressure can be between 0.1 cm H2O and 100 cm H2O and in some embodiments between 2 cm H2O and 50 cm H2O. Above this pressure, the flexible flap membrane (640) bends just enough to let the exhalation escape between the distal support (650). As soon as the expiratory airflow decreases, the flap membrane (640), which is shaped memory, can start its expansion and can maintain a relatively stable pressure in the airways.

[00164] Before the expiratory airflow ceases, the flap membrane (640) returns in the expanded configuration, thus maintaining the Positive End-Expiratory Pressure (PEEP) in the airways, which can be between 1 cm H2O and 50 cm H2O and in some embodiments between 2 cm H2O and 20 cm H2O. In order to modify the pressure of the Peak Expiratory Pressure (PEP) and the PEEP, the mobile incomplete seat (680), which may or may not have the same dimensions as the fixed incomplete seat (670), can be rotated over the fixed incomplete seat (670) to modify the support (650) of the flap membrane (640).

[00165] The support (650) can further include a clamping mechanism (690) operatively connected to the mobile incomplete seat (680) and which can be actuated to lock the mobile incomplete seat (680) in a position once the desired pressure is reached.

[00166] Referring to figures 16 to 18, there is shown a third alternative embodiment of the dynamic valve wherein the features are numbered with reference numerals in the 700 series which correspond to the reference numerals of the first embodiment of the dynamic valve.

[00167] In figures 16 to 18, the dynamic valve (700) comprises the flap membrane (740) located in the air passageway (32) of the cannula body (20) and is mounted to a proximal support (not shown). In some embodiment, the proximal support comprises a proximal anchoring system (764) located in the center of the proximal support and supported by two proximal spokes (755), which are aligned with one another in a manner such that they extend through a diameter of the proximal support, and to which the flap membrane (740) is mounted. The two proximal spokes (755) are located upstream of the flap membrane (740), i.e., closer to the proximal end (22). The proximal anchoring system (764) also includes a stem that extends towards the distal end of the cannula body (20) through the central perforation of the flap membrane (740).

[00168] The flap membrane (740), represented in the expanded configuration in figures 16 to 18, abuts against a fixed complete seat (772), extending substantially parallel to the proximal support, having substantially the same diameter as the proximal support, and being located downstream of the flap membrane (740), i.e., closer to the distal end of the cannula body (20). The fixed complete seat (772) protrudes inwardly from the peripheral wall (26) of the nasal cannula body (20) along an entire perimeter thereof. In an embodiment, the fixed complete seat (772) protrudes approximately 2 mm to 3 mm inside the cannula body (20).

[00169] In some embodiment, the dynamic valve (700) further comprises a fixed triangular support (774) and a mobile triangular support (782) that abuts against the inner periphery of the fixed complete seat (772) and in the center of the cannula body (20) against a distal anchoring system (762) of the support. The mobile triangular support (782) is on a different plan than the fixed triangular support (774) i.e., slightly spaced-apart from one another along the longitudinal axis of the nasal cannula body (20). The mobile triangular support (782) is retained in the center of the cannula body (20) by the distal anchoring system (762). The mobile triangular support (782) can overlay partially or entirely the fixed triangular support (774). The mobile triangular support (782) can slide freely on the inner periphery of the fixed complete seat (772) and is rotatable about the longitudinal axis, between a superposed configuration and a juxtaposed configuration. In the superposed configuration, the mobile triangular support (782) overlays entirely the fixed triangular support (774). In the superposed configuration, the surface of the flap membrane (740) is obstructed in a relatively tight manner of approximately 25% of its surface, as shown in figure 16. It is appreciated that the size of the fixed triangular support (774) and of the mobile triangular support (782) can vary.

[00170] In the juxtaposed configuration, the mobile triangular support (782) overlays a negligible portion of the fixed triangular support (774), such as the fixed triangular support (772) and the mobile triangular support (782) are substantially juxtaposed. In the juxtaposed configuration, the surface of the flap membrane (740) is obstructed in a relatively tight manner of approximately the sum of the surface of the fixed triangular support (774) and of the mobile triangular support (782), as shown in figure 18. Figure 17 represents an intermediate configuration of the mobile triangular support (782).

[00171] In an embodiment, the distal anchoring system (762) can be engaged with the proximal anchoring system (764).

[00172] In some embodiment, this lightweight flap membrane (740) is made of an elastic, anti-allergenic, tear-resistant material and is perforated with orifices (745) or slits over its entire surface. During inspiration, this lightweight flap membrane (740) folds around the two proximal spokes (755) to allow the inspiratory airflow to pass through without adding significant strain. During exhalation, this flap membrane (740) is pushed back against the fixed complete seat (772) and the fixed (774) and mobile (782) triangular supports, causing a resistance to the flow of exhaled air resulting in a rapid rise in upstream pressure, i.e. , closer to the proximal end (22), to reach a level determined by the rigidity of the membrane and the number of orifices (745) or slots cleared. The resulting peak pressure can be between 0.1 cm H2O and 100 cm H2O and in some embodiments between 2 cm H2O and 50 cm H2O. Above this pressure, the orifices (745) in the flap membrane expand just enough to let the expiration escape. As soon as the expiratory airflow decreases, the orifices (745) in the shaped memory flap membrane (740) close proportionally and maintains a relatively stable pressure in the airways. Before the expiratory airflow ceases, the orifices (745) of the flap membrane (740) close completely, thereby maintaining a predetermined residual pressure in the airways corresponding to the PEEP which can be between 1 cm H2O and 50 cm H2O and in some embodiments between 2 cm H2O and 20 cm H2O. To modify the pressure of the PEP and PEEP, the mobile incomplete seat (782) can be moved in different positions to obstruct or clear certain orifices (745) of the flap membrane (740), as shown in different configurations in figures 16, 17 and 18.

[00173] The fixed complete seat (772) can further include a clamping mechanism (790) operatively connected to the mobile triangular support (782) and which can be actuated to lock the mobile triangular support (782) in a position once the desired pressure is reached.

[00174] In some embodiment, as shown in figure 19, the nasal cannula (10) comprises a dynamic valve (500) but does not comprise a filter. This nasal cannula (10) can further comprise a protective grid (60) extending from and across the peripheral wall of the cannula body, the protective grid (60) being located closer to the cannula proximal end than the dynamic valve. The protective grid (60) prevents the dynamic valve (500) from being aspirated into the airway in case of detachment. This protective grid (60) should be located in the nasal cannula body (20) so as not to interfere with the dynamic valve clearance.

[00175] In some embodiment, as shown in figure 20, the distal end (24) of the nasal cannula (10) can be provided with a gripping means to facilitate its extraction from the nostril. This gripping means may be in the form of a prehension tongue (62) which can extend downwardly from the distal end (24) of the nasal cannula (10), which can be made of a similar material. The gripping means (62) can be added in any of the nasal cannula configurations described herein and shown in the accompanying drawings. [00176] Referring now to figures 21 to 23, there is shown a fourth embodiment of the nasal cannula wherein the features are numbered with reference numerals in the 300 series which correspond to the reference numerals of the first embodiment.

[00177] In the fourth embodiment of the nasal cannula (310), as shown in figure 21 , the nasal cannula (310) comprises a cannula body (320) and a valve (390). The cannula body (320) has a peripheral wall (326) made of an air impermeable material and extending between a proximal end (322) and a distal end (324), and defining an air passageway (332) extending between a proximal air port (334) and a distal air port (336). In an embodiment, the cannula body (320) can be divided in 3 sections in gas communication: an internal (proximal) portion (342), a middle (central) portion (340) and a valve receiver (distal) portion (344), the middle portion being located between the internal portion (342) and the valve-receiver portion (344) of the cannula body (320). In an embodiment, a cross-sectional surface area of the cannula body (320) in the middle portion (340) is greater than in the adjacent internal portion (342) and valve receiver portion (344). More particularly, in the middle portion (340), the cannula body forms an outwardly extending bulge.

[00178] As mentioned above, the cannula body (320) is made of an air impermeable material, which is also biocompatible shape memory material. This material can meet or exceed the international standards regulating the biocompatibility of medical devices ISO 10993 for contact with intact skin for less than 24 hours. Medical grade silicone is an example of a suitable material.

[00179] The valve (390) is operatively mounted to an internal surface of the peripheral wall (326) of the cannula body (320) in the valve-receiver portion (344), as will be described in more details below. It is appreciated that the valve (390) can be any one of the dynamic valves as described above in reference to figures 13 to 19. The dynamic valve allows an air flow through the cannula body (320) during an inspiration phase and selectively restricts the air flow through the cannula body during an expiratory phase. [00180] The internal portion (342) of the cannula body (320) extends upwardly between the proximal air port (334) and the middle portion (340) and is insertable in the user’s nostril with the proximal air port (334) being located inside the nasal vestibule of the user. In some embodiment, the internal portion (342) of the cannula body (320) can be frustoconical in shape. For example, the internal portion (342) of the cannula body (320) can have a length of about 1 mm to about 15 mm, and, in a particular embodiment, of about 5 mm and a diameter of about 5 mm to about 25 mm of outer diameter, and, in a particular embodiment, of about 10 mm of outer diameter. The diameter of the internal portion (342) can be significant enough to push the vibrissae to the sides and enlarge the air passage, especially at the level of the internal nasal valve by lateral traction on the adjacent tissues. The lateral traction on the adjacent tissues can also prevent leakage of air flow mainly on expiration, even with high expiratory pressure, between 5 cm and 30 cm H2O or more likely around 10 cm H2O.

[00181] The middle portion (340) with its outwardly extending bulge can ensure a shape memory of the cannula body (320) which can increase the comfort of the nasal cannula for the user by cushioning the impact of facial movement to the internal portion (342) of the cannula body (320) inserted in the nostril. In some embodiment, the canula body (320) in the middle portion (340) can be substantially resilient. At its apex, the middle portion (340) can be larger than the nostril inlet, thereby ensuring a sufficient sealing of the cannula body (320) within the nostril, even in case of face movements, preventing leakage of air flow and forcing a majority of the airflow to circulate within the air passageway (332).

[00182] The valve-receiver portion (344) extends between the middle portion (340) and the distal air port (336). An inner diameter of the valve-receiver portion (344) is configured to receive and contain the valve (390). When worn by a user, the middle portion (340) and the valve-receiver portion (344) are located externally of the nasal vestibule, extending substantially downwardly from the nostril inlet. In an embodiment, the peripheral wall (326) of the cannula body (320) in the valve-receiver portion (344) extends past a distal end of the valve (390), such that the valve (390) is surrounded by the peripheral wall (326) and entirely contained inside the cannula body (320), so as not to interfere with the movement of the flap membrane of the valve (390).

[00183] In an embodiment (not shown), the nasal cannula (310) can further comprise a supplemental filter, such as High Efficiency Particulate Air (HEPA) filtering material, extending from and across the air passageway (332), the supplemental filter being located in the valve-receiver portion (344) closer to the middle portion (340) than the valve (390), i.e., between the valve (390) and the middle portion (340). The supplemental filter is located in the air passageway (332) at a position that does not interfere with the dynamic valve clearance. The supplemental filter prevents the dynamic valve (390) from being aspirated into the airway in case of detachment and allows a filtration against pollution or microbes.

[00184] Figures 22 and 23 shows a respiratory mask and more particularly, a nasal mask assembly (400) including two nasal cannulas (310), as described above in reference to figure 21 , and a cannula connector (410). Each one of the two nasal cannulas (310) is insertable in a respective one of the two user’s nostrils. The two nasal cannulas (310) are connected together with the cannula connector (410) extending horizontally under a user’s nasal columella (8), when the nasal mask (400) is worn by a user. The cannula connector (410) can be a silicone strip, of about 5mm, substantially U-shaped. Ends of the cannula connector (410) are mounted to a respective one of the cannula bodies (320) in the middle portion (340) and to an outer surface thereof. It is appreciated that the ends of the cannula connector (410) can be connected to the valve-receiver portion (344).

[00185] In the embodiment shown, the nasal mask (400) further includes a head mount, embodied by two resilient straps (420) in the non-limitative embodiment shown. Each one of the two resilient straps (420) is connected to a respective one of the cannula bodies (320) in the middle portion (340) and to an outer surface thereof, diametrically opposed to the cannula connector (410). Each of the two elastic straps (420) is configured to be secured behind each of the two user’s ears. In some embodiment, the elastic straps (420) can be adjustable in length in accordance with a shape and a size of the user’s face. It is appreciated that the head mount can be connected to the valve-receiver portion (344) and can vary from the non-limitative embodiment shown.

[00186] In the embodiment shown, each of the two nasal cannulas (310) further comprise a connector plug (430), engageable with a sensor (not shown). The sensor can be a pressure sensor, a temperature sensor, a CO2 sensor, and a O2 sensor, for instance, configured to monitor at least one of a pressure, a temperature, a CO2 content, a O2 content, or any other relevant parameter inside the nasal cannula (310). In an embodiment, the sensor can be operatively coupled to a controller (not shown), for the user to monitor, control and/or regulate the pressure, the end tidal CO2 (EtCC ), the Oxygen Saturation (SpO2) and/or any other relevant parameters.

[00187] Turning now to Figures 24 and 25, there is shown another embodiment of a nasal mask assembly (400’), wherein the two nasal cannulas (310’) are in gas communication. As for the previous embodiment, the nasal mask assembly (400’) includes two nasal cannulas (310’), which are substantially similar to the ones described above in reference to figure 21 , except that they are in gas communication via their middle portion (340’). Each one of the two nasal cannulas (310’) is insertable in a respective one of the two user’s nostrils. However, they are made of a single cannula body (320’) having a common/shared middle portion (340’). Each one of the nasal cannulas (310’) has its own internal (proximal) portion (342) and valve receiver (distal) portion (344) with a valve (390) contained in the valve receiver (distal) portions (344). In the middle portion (340’) of the cannula body, the nasal mask assembly (400’) extends under the user’s nasal columella (8).

[00188] In an alternative embodiment (not shown), the canula body (320’) of the nasal mask assembly (400’) includes a single valve receiver (distal) portion (344) containing a single valve (390). In this embodiment, the single valve receiver (distal) portion (344) can extend downwardly from approximately a center of the middle portion (340). [00189] As for the embodiment shown in figures 22 and 23, the nasal mask assembly (400’) includes a head mount embodied by two elastic straps (420), in the non- limitative embodiment shown. Each one elastic straps (420) are connected to a respective side of the middle portion (340’) of the cannula body.

[00190] As for the embodiment shown in figures 22 and 23, the nasal mask assembly (400’) also includes a connector plug (430’), configured to connect a sensor, as detailed above.

[00191] Figures 26 and 27 show a third embodiment of a nasal mask assembly (400”) wherein the valves 390 of the embodiments shown in figures 21 to 25 are replaced with two unidirectional valves (800), each one allowing an incoming air flow through the cannula body (420) during an inspiration phase and preventing an outcoming air flow out of the cannula body (420) during an expiratory phase. The unidirectional valves (800) are also referred to as one-way respiratory valves or check valves. They permit the air flow in only one direction and prevent the air flow in the other direction. In this embodiment, the nasal mask assembly (400”) further comprises a pop-off valve (850), allowing the outcoming air flow to escape from the nasal mask. The pop-off valve (850), also referred to as a positive pressure relief valve, allows the user to preset a requested pressure, by adjusting the Positive End-Expiratory Pressure (PEEP). The pop-off valve (850) opens automatically when the pressure in the air passageway of the cannula body reaches a predetermined pressure and discharge airflow until pressure drops to acceptable levels. The pop-off valve (850) can be adjustable in that its pressure threshold to be configured in the open configuration can be modified/adjusted.

[00192] As for the nasal mask assemblies (400, 400’), the nasal mask assembly (400”) can include a connector plug (430’) and a head mount, such as the resilient bands, to secure the mask to a user face.

[00193] Referring now to figure 28, there is shown an embodiment for a respiratory nasal mask (900) including two valves (990). The respiratory nasal mask (900) also includes a mask body (910), a cushion (915), and a head mount, such as head strap (920).

[00194] In the embodiment, the mask body (910) includes a triangularly shaped hollow shell made of an air impermeable biocompatible material, such as and without being limitative silicon. In an embodiment, the impermeable biocompatible material is a shape memory material. The mask body (910) is configured to cover and envelop the user’s nose, from a top of the user’s nasal bone to finish under the nose, on the philtrum (9) of the user. The mask body (910) extends on both sides of the nose, at the junction between the nose and the cheeks. When mounted to the user’s face, the mask body (910) defines an internal breathing chamber.

[00195] The cushion (915) is mounted to the mask body (910) and, more particularly, to a peripheral edge thereof. The cushion (915) abuts against the user’s face and is configured to form a seal between the mask body and the user’s face. In an embodiment, the cushion (915) can be inflatable or pre-inflated, or made of any suitable material soft enough to increase the comfort of the user and to ensure a sufficient sealing of the mask body (910) with the user’s face, even with high expiratory pressure (for instance, between 3 cm and 50 cm H2O or more likely around about 10 cm H2O).

[00196] In a non-limitative embodiment shown, the head mount (920) includes at least three straps, each one being connected at a first end to a vertex of the triangularly shaped hollow shell and being connected at the opposed end to a headgear (not shown), such as a head band, adjustable around the user’s forehead, or any headgear configured to secure the mask body (910) to the user’s face. In an embodiment, the head straps (920) can be adjusted in length to pull the mask body (910) against the user’s face with sufficient force to achieve a seal therebetween.

[00197] The respiratory nasal mask (900) shown in figure 28, includes the two valves (990) operatively mounted to a side of the mask body (910) facing the user’s nostrils and more particularly, substantially aligned therewith. In an embodiment, the two valves (990) can be any one of the dynamic valves as described above in reference to figures 13 to 19. The dynamic valve allows an airflow through the mask body (910) during an inspiration phase and selectively restricts the air flow through the mask body (910) during an expiratory phase.

[00198] In another embodiment (not shown), the two valves (990) can be two unidirectional valves with fixed orifices. It is understood that in such embodiment, the first unidirectional valve allows an incoming air flow through the mask body (910) during an inspiration phase and the second unidirectional valve allows an outcoming air flow out of the mask body (910) during an expiratory phase.

[00199] In an embodiment (not shown), the respiratory nasal mask (900) can further include a supplemental filter, made of filtering material such as HEPA, and covering an internal part of the valves (990). The supplemental filter prevents the valves (990) from being aspirated by the user in case of detachment and allows a filtration against pollution or microbes. This supplemental filter is located in the mask body (910) so as not to interfere with the valve clearance.

[00200] The respiratory nasal mask (900) can further include a connector plug (930), which can be similar to the one described above in reference to figure 21 .

[00201] Figure 29 shows an alternative embodiment for a respiratory nasal mask (900’), where the two valves are unidirectional valves (995). Thereby, the unidirectional valves (995) are configured for allowing an incoming airflow through the mask body (910) during an inspiration phase and preventing an outcoming air flow out of the mask body (910) during an expiratory phase.

[00202] In this embodiment, the respiratory nasal mask (900’) further includes a pop-off valve (996), allowing the outcoming air flow to escape from the mask body (910). A pressure threshold of the pop-off valve (996), i.e. , the pressure at which the pop-off valve (996) is configured in the open configuration, can be selected in accordance with the user’s needs. In some embodiments, the pop-off valve can be adjustable in that its threshold to be configured in the open configuration can be modified. The pop-off valve (996) opens automatically when the pressure in the mask body (910) reaches the preset pressure, and an airflow is released until pressure drops to acceptable levels.

[00203] Figure 30 shows a filtering nasal (respiratory) mask (450) including a mask body (460) and a head mount (470).

[00204] The mask body (460) has substantially the same shape as the mask bodies shown in figures 28 and 29. Furthermore, it can be made of the same filtering material as the one described above in reference to figure 4. Therefore, it will not be described in further details.

[00205] Similarly, the head strap (470), used as an example of a head mount, is similar to the one described hereinabove in reference to figure 28 and will not be further described.

[00206] The filtering nasal mask (450) includes at least one mechanical connector (440) mounted to a lower edge of mask body (460) in a manner such that it covers a user’s philtrum. In the non-limitative embodiment shown, the mechanical connector includes a Velcro™. It is appreciated that similar mechanical connectors can be provided on any one of the masks shown in figures 28 and 29 and on the nasal mask assemblies (400, 400’) of figures 24 to 27.

[00207] As the embodiment shown in figures 28 and 29, the filtering nasal mask (450) can include a cushion mounted to the mask body (460) and, more particularly, to a peripheral edge thereof. Such cushion is similar to the cushion (915) described hereinabove and will not be described in further details below.

[00208] Figure 31 shows another embodiment of a filtering nasal (respiratory) mask (450’), wherein the filtering nasal mask is similar to the one described above in reference to figure 30 but further including two valves (490), operatively mounted to a side of the mask body (460) in a manner such that they are facing (or are substantially aligned with) the user’s nostrils. In an embodiment, the two valves (490) can be two unidirectional valves with fixed orifices, allowing the outcoming hot and wet air flow out of the mask body (460) during an expiratory phase, but preventing the incoming air flow through the mask body (460) during an inspiration phase. Therefore, the user is forced to inspire the incoming air flow through the filtering material of the mask body (460). This filtering nasal mask (450’) can increase the comfort felt during exhalation while not significantly favoring the propagation of microbes exhaled through the nose, whose airflow does not reach the speed of a brutal oral exhalation.

[00209] Figure 32 shows a filtering nasal (respiratory) mask (450”) having a mask body (460”) with a different shape and an alternative face engagement assembly from the one shown in Figures 28 to 31 .

[00210] The shape of the mask body (460”) differs from the one shown in Figures 28 to 31 , extending more laterally to further cover the user’s cheeks in addition to the user’s nose. The mask body (460”) is made of an air permeable, biocompatible, and shape memory filtering material.

[00211] The filtering nasal mask (450”) includes a head mount, embodied by two elastic straps (420) in the non-limitative embodiment shown. Each one of the two resilient straps (420) is connected to a respective one of the lateral edges (466, 468) of the mask body (460”). Each one of the two resilient straps (420) is configured to engage a respective one of the user’s ears as it is known in the art. In some embodiment, the resilient straps (420) can be adjustable in length in accordance with a shape and a size of the user’s face.

[00212] Referring now to figure 33, there is shown an embodiment of an oronasal respiratory mask (940). The oronasal respiratory mask (940) includes a mask body (942), a head strap (943), two unidirectional valves (995), and a pop-off valve (950), which can be adjustable.

[00213] The mask body (942) includes a triangularly shaped hollow shell made of an air impermeable biocompatible material, such as and without being limitative silicon. In an embodiment, the impermeable biocompatible material is made of a shape memory material. The mask body (942) is configured to cover and envelop both the user’s mouth and the user’s nose, from a top of the user’s nasal bone to finish under the mouth, on a user’s chin. The mask body (942) extends on both sides of the nose, at the junction between the nose and the cheeks. When mounted to the user’s face, the mask body (942) defines an internal breathing chamber. In a non-limitative embodiment, the oronasal respiratory mask (940) can further include a cushion mounted to the mask body (942) and, more particularly, to a peripheral edge thereof. Such cushion is similar to the cushion (915) described hereinabove and will not be described in further details below.

[00214] In the non-limitative embodiment shown, the head mount (943) includes three straps, each one being connected at one end to a respective vertex of the mask body (942) and being connected at another end to a headgear, such as a head band (944), adjustable around the user’s forehead. It is appreciated that any suitable headgear configured to secure the mask body (942) to the user’s face can be used. In an embodiment, the head straps (943) can be adjustable in length to pull the mask body (942) against the user’s face with sufficient force to achieve a sufficient seal between the mask body (942) and the user's face. It is understood that other configuration of the head strap (470) can exist as head mount, including but not limited to two straps, such as elastic straps passed behind the head of the user, to maintain the mask body (942) in contact with the user’s face.

[00215] The two unidirectional valves (995) are operatively mounted to the mask body (910) in a configuration such that they are located under user’s nostrils when the oronasal respiratory mask (940) is worn. In an embodiment, the two valves are substantially aligned with user’s nostrils. The unidirectional valves (995) allow an incoming air flow in the mask body (942) during an inspiration phase and preventing an outcoming air flow out of the mask body (942) during an expiratory phase.

[00216] As for the above-described embodiment, the oronasal respiratory mask (940) can further include a supplemental filter. This filtering has been described above and will not be further described. [00217] The pop-off valve (950) is operatively mounted to the mask body (942) and, more particularly, via a silencer tubing (960) and a unidirectional valve (970). The unidirectional valve (970) is mounted to the mask body (942), in a lower part thereof and substantially centered. The silencer tubing (960) has a proximal end connected to an end of the unidirectional valve (970). The unidirectional valve (970) and the silencer tubing (960) provide gas communication between the internal breathing chamber defined between the mask body (942) and the user’s face and the pop-off valve (950) mounted at a distal end of the silencer tubing (960). Thus, the silencer tubing (960) extends between the mask body (942) and the pop-off valve (950), to facilitate access to the pop- off valve (950) and/or to reduce expiration noise. The pop-off valve (950) allows the outcoming air flow to escape from the internal breathing chamber defined between the mask body (942) and the user’s face. Thus, the internal breathing chamber, the silencer tubing (960) and the pop-off valve (950) are in gas communication.

[00218] The unidirectional valve (970) allows the outcoming air flow out of the internal breathing chamber into the silencer tubing (960) during the expiratory phase and prevents the incoming air flow from the silencer tubing (960) into the internal breathing chamber during the inspiration phase, to prevent the user to inhale previously exhaled air.

[00219] As for the above-described embodiments, the oronasal respiratory mask (940) can further comprise a connector plug (945), configured to connect a sensor. Similar connector plugs have been described for the previous embodiments and will not be described in further details.

[00220] Figure 34 shows another embodiment of an oronasal respiratory mask (940’), where the silencer tubing (960) as described above in reference to figure 33 further includes a bulge defining an air chamber (962), which is filled with a portion of the outcoming air flow during the expiratory phase, until the pressure in the chamber reaches a predetermined pressure threshold which is function of the pop-off valve (950). Once the pressure is above the pop-off valve (950) threshold, the latter opens letting the outcoming air flow being discharged until pressure inside the silencer tubing (960) drops below the pressure threshold.

[00221] The oronasal respiratory mask (940’) can further include a volume adjuster, embodied by a ring (964) in the non-limitative embodiment shown, mounted to the silencer tubing (960) and translatable therealong to modify a volume of the air chamber (962) by modifying a volume of the bulge.

[00222] In an embodiment (not shown), the oronasal respiratory mask (940’) can also include a CO2 capture device, mounted to a lateral surface of the silencer tubing (960), for instance substantially in a middle of the air chamber (962). More particularly, a CO2 capture device port can be defined in a peripheral wall of the silencer tubing (960) to prevent disruption of the air flow circulation. The capture device can be in gas communication with the air chamber (962) via the CO2 capture device port. The CO2 capture device can contain a removable pouch, filled with porous granules including without being limitative activated carbon, calcite minerals or manganese silicate, or any material capable of capturing and fixing the excess of CO2 from the airflow circulating in the air chamber (962). The CO2 capture device port can be mounted to the silencer tubing (960) via a mechanical connector, such as and without being limitative a magnet. In an embodiment, the mechanical connection between the CO2 capture device and the silencer tubing (960) is detachable in a manner such that the CO2 capture device (or its content) can be replaced by a new one once filled of CO2. It is understood that the size and the shape of the removable pouch can vary, depending on the size of the silencer tubing (960).

[00223] Turning now to figure 35, there is shown an embodiment of a buccal respiratory mask (980) combined with any one of the nasal mask assemblies of figures 21 to 31. The buccal respiratory mask includes a mask body (982), a head mount, such as the head strap (983) shown, two unidirectional valves (995), and a pop-off valve (950), which can be adjustable. [00224] The mask body (982) includes an oval shaped hollow shell made of an air impermeable biocompatible material, such as and without being limitative silicon, configured to surround the user’s mouth. In an embodiment, the impermeable biocompatible material is shape memory material. When superposed to the user’s face, the mask body (982) defines therewith an internal breathing chamber. In a non-limitative embodiment, the mask body (982) can further include a cushion mounted to the mask body (982) and, more particularly, to a peripheral edge thereof. Such cushion is similar to the cushion (915) described hereinabove and will not be described in further details.

[00225] In the non-limitative embodiment shown, the head mount (943) includes at least one strap, connected at one end to two different attachment points of the mask body (982) and at another end behind the head of the mask user.

[00226] The two unidirectional valves (995) are operatively mounted to the mask body (982) and spaced apart from each other. As the above-described unidirectional valves, the unidirectional valves (995) allow an incoming air flow in the mask body (982) during an inspiration phase and preventing an outcoming air flow out of the mask body (982) during an expiratory phase.

[00227] The assembly including the pop-off valve (950), the silencer tubing (960), and the unidirectional valve (970) is substantially similar to the one shown in figure 33 and described above. Therefore, it will not be described in further details. However, instead of being mounted to a mask that covers simultaneously the user’s nose and mouth, the unidirectional valve (970) is mounted to the mask body (982) covering solely the user’s mouth.

[00228] As for the above-described embodiments, the buccal respiratory mask (980) further includes a connector plug (985), configured to connect a sensor, and a mechanical connector (998) mounted to an upper side of the mask body (982) and extending upwardly on a user’s philtrum. In the embodiment shown, the mechanical connector (998) is engageable with a nasal mask assembly, which can be anyone of the nasal mask assemblies of figures 21 to 31 or an alternative / combination thereof. The combination of the buccal respiratory mask (980) with the nasal mask assembly (400”) or the filtering nasal mask (450) forms an oronasal mask (999). The oronasal mask (999) prevents the user to inhale microbes and also prevents the user to propagate pathogens in the ambient air.

[00229] Whenever possible, the material of the cannula body, the mask body, the filter material and, if used, the dynamic valve and its seat can be reusable, washable and biodegradable.

[00230] It is appreciated that the nasal cannula, the filtering nasal mask, the oronasal respiratory mask, the buccal respiratory mask can be provided in different size to adapt to the face of the user.

[00231] It is appreciated that in the embodiments described above, the shape and the configuration of the cannula bodies, the masks, the head mount, and the like can vary from the embodiments shown. Furthermore, it is appreciated that combination of the different embodiments can be foreseen.

[00232] The above-described nasal filter cannulas do not suffer from at least part of the ergonomic drawbacks related to conventional masks. The nasal filter cannula can be easier and quicker to adjust in the nasal vestibule and once in place, it can be almost imperceptible to everyone. The lumen of the internal nasal valve being 2 to 3 times smaller in diameter than the nasal vestibule can ensure that the nasal filter cannula cannot be sucked into the airway even after the lumen is enlarged by the expanding cannula. The nasal filter cannula substantially prevents fogging in the eyeglasses or increased heat and moisture to the face. Access to the mouth is always allowed and the comfort of the nasal filter cannula allows it to be worn continuously for many hours, becoming a breathing orthosis that is forgotten, as contact lenses are for the eyes. When wearing a nasal filter cannula, the only time the air is not be filtered is when the user breathes through the mouth. However, typically, a nasal filter cannula does not promote mouth breathing because the natural resistance encountered during inspiration is decreased thanks to the enlargement of the internal nasal valve which represents 50% of the resistance of the upper airways and by the effect of the spreading of the vibrissae, sometimes bushy, of the nasal vestibule.

[00233] In addition, the flexible configuration of the nasal filter cannula can substantially prevent any leaks around the filtering material so that it can be said that 100% of the air inhaled and exhaled through the nose can be filtered.

[00234] The ease of breathing through the nose and the comfort of the nasal filter cannula can encourage the user to wear it longer, significantly increasing the amount of pollution particles and contaminants filtered in a 24-hour period. Even if, despite these characteristics, the user sometimes breathes through his mouth (about 8% of the time when awake and 4% when asleep), for example when he wants to finish a sentence quickly, the quantity of unfiltered air at the end of the day can be less than with a face mask. Moreover, it is possible for a user to become aware of his breathing, allowing him to limit his mouth breaths, for example, to take the time to breathe in through his nose in the middle of a sentence before completing it. For instance and without being limitative, the use of the nasal filter cannula alone can be particularly indicated in a context of gathering people who do not use speech for example: as spectators at the theater, at the cinema, at the concert, at the library, during lectures or even during participative courses whereas the speakers who want to express themselves can simply have to put a rectangular mask on their mouth before speaking. A rectangular procedural mask can be easier to maintain only on the mouth rather than on both the nose and the mouth which forms an unstable triangle, conducive to leaks and causes frequent repositioning of the mask on the nose.

[00235] This rectangular mask can be held in place not by elastic bands around the ears, which can injure them by prolonged traction, but simply around the neck, which can increase tolerance to wearing the mask. This mask can be lowered to the level of the neck when not in use, thus remaining within reach and available at all times. One can also consider wearing both the Nasal Filter and a mouth mask, which can complement each other to offer optimal personal and community protection. In some special circumstances, such as during sleep, existing accessories can be used to keep the mouth closed.

[00236] Furthermore, the recent advent of nanofibers as a filtration material improves filtration capacity and/or decreases airflow resistance. These new performances open the door to new alternative products that meet a growing and well- identified need. The filtration capacity of a material versus its resistance to airflow can be directly proportional to the filtration surface of this material for a given airflow. Therefore, nasal filter cannula can be offered in different applications to meet the filtration and breathing resistance needs of various users.

[00237] Regarding the filtering nasal masks, they are suitable for people who wishes to improve their personal protection against the inhalation of deleterious particles via the nasal route.

[00238] The nasal route is a main entry point to the respiratory system. It is known that the nose is an ideal environment for the proliferation of inhaled pathogens; warm, moist conditions and nasal folds contribute to this. The marked presence of Angiotensinconverting enzyme (ACE2) proteins in the nasal cavity serves as receptors for COVID viruses, which attach to the nasal cavity before spreading throughout the respiratory system.

[00239] Wearing procedural masks do not provide effective protection against nasal inhalation of deleterious particles because of the many common internal leaks around the nose. The filtering nasal mask can be easier to fit over the nose and can complement the effectiveness of face masks. Because it is less bulky, less hot and humid, the filtering nasal mask can be worn for longer periods of time, even during meals or drinking, thus filtering out more airborne particles in a 24-hour period.

[00240] Several alternative embodiments and examples have been described and illustrated herein. The embodiments of the invention described above are intended to be exemplary only. A person of ordinary skill in the art would appreciate the features of the individual embodiments, and the possible combinations and variations of the components. A person of ordinary skill in the art would further appreciate that any of the embodiments could be provided in any combination with the other embodiments disclosed herein. It is understood that the invention may be embodied in other specific forms without departing from the central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein. Accordingly, while the specific embodiments have been illustrated and described, numerous modifications come to mind. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.