Patent Description:
Noninvasive ventilation (NIV) is the delivery of respiratory support without using an invasive artificial airway such as an endotracheal tube. Noninvasive positive pressure ventilation can be implemented using a mechanical ventilator connected by tubing to a mask that directs airflow into the patient's nose or the nose and mouth. Head straps are used to secure the mask to the patient. Use of single-limb, positive-pressure ventilation delivered through a mask is a recognized method for providing noninvasive respiratory support to patients, and is an integral tool in the management of both acute and acute on chronic respiratory failure.

An exhalation port is used to evacuate a patient's exhaled gasses from a single-limb, NIV breathing circuit when a non-vented mask is used. During exhalation, the patient's exhaled gases flow out of the exhalation port located in-line with the breathing circuit at the connection between the mask and the air flow conduit. In use, the exhaled gases are pushed through the port by the incoming gases at therapeutic pressure rates sufficient to keep rebreathing of carbon dioxide (CO<NUM>) at acceptable levels. Improvements to exhalation ports are desired to reduce draft from the exhalation port, to reduce noise of exhaled gas exiting the exhalation port, and to provide the ability to filter the exhaled gas.

Patent document <CIT> is hereby acknowledged.

According to a first aspect of the disclosure, there is provided an exhalation port device for use with a single-limb noninvasive ventilation apparatus which conveys gases along a gases pathway and delivered to a patient via a mask, where the exhalation port device comprises an elongate body that is hollow and defines a lumen to carry a flow of gases; a plurality of openings arranged on a portion of the elongate body, the openings configured to vent gases through the openings; a shroud extending from the elongate body, the shroud surrounding one or more of the plurality of openings; wherein the plurality of openings are tapered; and wherein the exhalation port is arranged to removably connect in-line with a circuit for delivering gases to a patient.

In some embodiments the shroud extends outward from the elongate body.

In some embodiments the shroud extends outward from the elongate body in a substantially annular form.

In some embodiments the shroud extends outward from the elongate body approximately normal to the elongate body.

In some embodiments the shroud extends outward from the elongate body at an angle of between approximately <NUM> degrees and approximately <NUM> degrees.

In some embodiments the shroud has a wall which extends outward from the elongate body and an internal portion of the wall is tapered inwardly, the taper extending from a portion of the shroud adjacent the elongate body to an outside surface of the shroud, the taper being at an angle between approximately <NUM> degree and approximately <NUM> degrees.

In some embodiments the shroud has an outside surface, and the outside surface has a <NUM> taper configured to removably connect with a filter.

In some embodiments the shroud has an outside surface, and the outside surface of the shroud has a plurality of notches.

In some embodiments the plurality of notches are spaced equally around the outside surface of the shroud.

In some embodiments each of the plurality of notches comprises a notch dimension and a spacing dimension.

In some embodiments each of the plurality of notches comprises a notch dimension that is substantially equal to the spacing dimension.

In some embodiments each of the plurality of notches comprises a notch dimension that is substantially greater than the spacing dimension.

In some embodiments the shroud has an outside surface, and the outside surface of the shroud is substantially planar.

In some embodiments the shroud is offset and extends at an angle to the elongate body.

In some embodiments the shroud is hingedly attached to the elongate body.

In some embodiments the shroud is removable from the elongate body.

In some embodiments the elongate body further comprises a first end, wherein the first end of the elongate body comprises a <NUM> male taper and a <NUM> female taper nested within the <NUM> male taper.

In some embodiments the shroud has a wall and the wall has a plurality of slots.

In some embodiments the plurality of slots are substantially oval.

In some embodiments the plurality of slots are substantially circular.

In some embodiments the shroud has an outer wall and the outer wall has alternating recessed strips and ridges around a circumference of the outer wall.

In some embodiments the shroud has an outer wall and an outer surface, the outer wall having alternating recessed strips and ridges around a circumference of the outer wall, the outer surface having a plurality of notches, and the recessed strips and the notches are aligned.

In some embodiments the exhalation port includes a filter connector adaptor configured to connect the shroud with alternating recessed strips and ridges to filter.

In some embodiments the shroud has a free portion that is substantially annular and wherein the substantially annular free portion of the shroud comprises at least one slot.

In some embodiments the plurality of slots are substantially radially positioned on the wall of the shroud.

In some embodiments the plurality of slots are substantially axially positioned on the wall of the shroud.

In some embodiments each of the plurality of openings is tapered such that it is widest on an external surface of the opening.

In some embodiments each of the plurality of openings has a diameter at an internal surface of the opening, a radius at an external surface of the opening, and a depth.

In some embodiments for each of the plurality of openings the diameter at an internal surface of the opening is between approximately <NUM> and approximately <NUM>.

In some embodiments for each of the plurality of openings the radius at an external surface of the opening is between approximately <NUM> and approximately <NUM>.

In some embodiments for each of the plurality of openings the depth is at least two times the diameter at an internal surface of the opening.

In some embodiments each of the plurality of openings has a center, and wherein the exhalation port further comprises a pitch distance for each of the plurality of openings, the pitch distance being a distance between the center of a first opening and the center of those of the plurality of openings that are adjacent to the first opening.

In some embodiments each of the plurality of openings has a diameter, and the pitch distance for each of the plurality of openings is at least four times the diameter.

In some embodiments the diameter is between approximately <NUM> and approximately <NUM>.

In some embodiments the plurality of openings are arranged in an offset pattern within the shroud.

In some embodiments the offset pattern is such that each opening is offset from each other opening.

In some embodiments one of the plurality of openings is a central opening and a remainder of the plurality of openings are arranged in a circular pattern within the shroud such that the remainder of the plurality of openings extend in at least one circular arrangement around the central opening.

In some embodiments the plurality of openings are arranged in a square pattern such that each opening is aligned with an adjacent opening.

In some embodiments the plurality of openings comprises between <NUM> and <NUM> openings arranged in a square pattern such that each opening is aligned with an adjacent opening.

In some embodiments the plurality of openings comprises <NUM> openings arranged in a square pattern such that each opening is aligned with an adjacent opening.

In some embodiments the exhalation port includes a removably attachable filter that can be removably attached to the shroud.

In some embodiments the removably attachable filter is a sintered plastic filter.

In some embodiments the exhalation port includes a filter that is permanently attachable to the plurality of openings.

In some embodiments the exhalation port includes a filter that is permanently attachable to the shroud.

In some embodiments the exhalation port includes a filter that is a cap that is removably placeable in the shroud.

In some embodiments the exhalation port includes a filter that is a disk made of sintered plastic that is removably placeable in the shroud.

In some embodiments the exhalation port includes a filter that is a diffuser that is removably placeable in the shroud.

In some embodiments the exhalation port includes a filter that is integrated around the plurality of openings onto the elongate body, and wherein the filter also includes a hole defining a gases passageway.

In some embodiments the exhalation port includes a filter that is a membrane disk that is positioned within two parts.

In some embodiments the exhalation port includes a pressure port extending outward from the elongate body, the pressure port configured to couple with a pressure sampling line that connects to a noninvasive ventilator.

According to a another aspect of the disclosure, there is provided a noninvasive ventilation mask system for use with a single-limb noninvasive ventilation apparatus which conveys gases along a gases pathway and delivered to a patient via a noninvasive ventilation mask, where the noninvasive ventilation mask system comprises:.

Preferably the soft seal comprises a rolling hinge portion at the nasal bridge.

Preferably the noninvasive ventilation mask system includes a headgear arrangement comprising a pair of upper strap portions, each upper strap portion positioned on opposing sides of a patient's head, a crown strap extending between the two upper strap portions, the crown strap extending across a crown of the patient's head.

Preferably the exhalation port further comprises:.

Further aspects of the present disclosure, which should be considered in all its novel aspects, will become apparent to those skilled in the art upon reading of the following description which provides at least one example of a practical application of the present disclosure.

Various embodiments of the present disclosure will now be described, by way of illustrative example only, with reference to the accompanying drawings. In the drawings, similar elements have the same reference numerals.

Embodiments of the present disclosure include an exhalation port for use with, among other things, a single-limb, noninvasive ventilation (NIV) system. The disclosed embodiments are used to evacuate a patient's exhaled gasses from a breathing circuit. During exhalation, the patient's exhaled gases flow out of the exhalation port located in-line between the patient interface device (e.g., a mask) and the air flow conduit from the ventilator or gases source. In use, the exhaled gases are pushed through vent openings, or holes, in the port by the incoming gases at therapeutic pressure rates sufficient to keep rebreathing of carbon dioxide (CO<NUM>) at acceptable levels.

Referring to <FIG>, illustrated is a perspective view of a mask <NUM> with an exhalation port <NUM> attached in accordance with an embodiment of the present disclosure. The exhalation port <NUM> is attached to the elbow connector <NUM> of the full face mask <NUM>. In some embodiments, the exhalation port <NUM> can be used with other types of patient interfaces, such as pillow masks, oral masks, oral-nasal masks, nasal masks, and the like. In the illustrated configuration, the exhalation port <NUM> is disposed in-line with a gases conduit <NUM>, such that the exhalation port <NUM> has a first end <NUM> that is in fluid communication with an inlet <NUM> to the mask <NUM> and a second end <NUM> that is in fluid communication with a ventilator or gases source via a gases conduit <NUM>. The exhalation port <NUM> is preferably attached to the elbow connector <NUM> at or near the inlet <NUM> of the mask <NUM>. Positioning the exhalation port <NUM> close to the mask inlet <NUM> beneficially reduces the amount of dead space where CO2 gases can accumulate and beneficially reduces the rebreathing of exhaled gases by the patient.

<FIG> show perspective views of an exhalation port <NUM> in accordance with an embodiment of the present disclosure, and <FIG> and <FIG> illustrate front, top and bottom views, respectively, of the embodiment <NUM>. As shown in <FIG>, the exhalation port <NUM> includes an elongate body <NUM> having a hollow portion extending through a longitudinal axis <NUM> of the exhalation port <NUM>, defining a lumen <NUM> through which gases may flow. The exhalation port <NUM> includes a top portion <NUM>, a center portion <NUM>, and a bottom portion <NUM>.

Preferably the exhalation port <NUM> is constructed of a relatively inflexible material such as, for example, polycarbonate plastic. Such a material can provide the requisite rigidity. Advantageously, polycarbonate provides transparency permitting clinicians to see inside the exhalation port <NUM> for secretions or blockages that might form. Polycarbonate also delivers good dimensional stability. Other materials known in the art can be used to realize the disclosed exhalation port <NUM>, including without limitation, polypropylene and Polyethylene Terephthalate Glycol-Modified (PETG).

The top portion <NUM> includes a <NUM> male taper <NUM> and <NUM> female taper <NUM> nested within the <NUM> male taper <NUM> to enable connection to various patient interfaces, such as, for example, the elbow connector <NUM> of the mask <NUM>. The <NUM> female taper <NUM> can be used to connect to a tracheostomy tube. Other connection formats can be included in embodiments of the disclosed exhalation port <NUM> as well. For example, the outside surface <NUM> of the of the shroud <NUM> may include a proprietary connector configured to allow one or more proprietary external filters to be connected to the exhalation port <NUM>. Additionally, at least one of the top portion <NUM> and bottom portion <NUM> can have a proprietary connection configured to mate with a proprietary elbow connector <NUM> to help ensure that exhalation ports <NUM> and masks <NUM> offered by the same manufacturer can be used together at the exclusion of other manufacturers' products. The bottom portion <NUM> includes a <NUM> male taper <NUM> (shown in <FIG>) to connect to the gases conduit <NUM>. The center portion <NUM> includes a <NUM>/<NUM> inch pressure line port <NUM> to couple with a pressure sampling line that connects to the noninvasive ventilator or gases source. When the pressure line port <NUM> is not in use, it may be closed off with a cap (not shown).

The center portion <NUM> of the exhalation port <NUM> also includes a plurality of vent holes <NUM> (also referred to herein as "openings <NUM>") through which the patient's exhaled gases can be evacuated from the breathing circuit. A shroud <NUM> is positioned over and around the vent holes <NUM> to reduce draft from the exhaled gas. The shroud <NUM> is substantially annular. The shroud <NUM> allows venting of the exhaled gases and prevents blockage of the vent holes <NUM>. Illustratively, the shroud <NUM> prevents entrainment of surrounding ambient air within the exhalation stream through the vent holes <NUM>. The shroud <NUM> also has a <NUM> male taper at an outside surface <NUM> providing structure to which an external filter <NUM>, <NUM> (shown in <FIG>) can be attached. The external filter <NUM>, <NUM> prevents exposure to clinicians and others in proximity of the patient to infectious agents that may be in the patient's exhaled gases. Thus, the filter <NUM>, <NUM> reduces the chance of infections spreading due to sick patients exhaling in a hospital setting.

The shroud <NUM> has an inner wall <NUM> that extends outward from the center portion <NUM> of the exhalation port <NUM>. In accordance with certain embodiments, the inner wall <NUM> of the shroud <NUM> is tapered centrally. The taper extends from a portion of the shroud adjacent the elongate body to the outside surface <NUM> of the shroud <NUM> at an angle between <NUM> degrees and <NUM> degrees. In some embodiments the shroud is not tapered centrally.

The shroud <NUM> can include notches <NUM> which can reduce the chance of missuse by differentiating the shroud <NUM> from a wye-piece or T-piece so the shroud's taper is not used in a dual-limb NIV circuit. The notches <NUM> also reduce the probability of accidentally blocking the exhalation path. As illustrated in the embodiment disclosed in <FIG>, the notches <NUM> are positioned on the outside surface <NUM> of the shroud <NUM>. The dimensions, spacing, and number of the notches <NUM> can vary. For example, as illustrated in <FIG>, the notches <NUM> are positioned diametrically opposite each other on portions of the outside surface <NUM> of the shroud <NUM>.

Illustrated in <FIG>, is a preferred embodiment of the exhalation port <NUM> in which the shroud <NUM> includes four equally-spaced notches <NUM>, having a rounded spacing between them. In some embodiments (as illustrated in <FIG> and <FIG>), the notches <NUM> are spaced equally around the outside surface <NUM> of the shroud <NUM>, and the dimensions of the notches <NUM> are substantially equal to the spacing dimensions between the notches <NUM>. In certain embodiments, the notches <NUM> have a dimension that is substantially greater than the dimension of the spacing between the notches <NUM>. Many other forms and variations of notch <NUM> dimension, arrangement, and spacing can be used.

<FIG> illustrate embodiments of the exhalation port <NUM> that employ slots <NUM> on the shroud <NUM>. Like the notches <NUM>, the slots <NUM> help prevent the vent holes <NUM> from being blocked. The slots <NUM> also allow venting of exhaled gases to the surrounding environment, and they serve to reduce the chance of inappropriate use of the exhalation port <NUM> by differentiating the shroud <NUM> to indicate that it is not to be used in a dual-limb NIV breating circuit. The slots <NUM> also reduce the probability of accidentally blocking the exhalation path. The slots <NUM> can be in any form or shape, such as, for example, round or oval, and their orientation can be radially positioned around the surface of the shroud <NUM>, axially positioned, directed toward the center portion <NUM>, or positioned in any other orientation on the shroud <NUM>. The slots <NUM> are preferably sufficiently close to the outside surface <NUM> of the shroud <NUM> such that they can be covered by a <NUM> female taper connection of an external filter <NUM>, <NUM> (as shown in <FIG>) to prevent unfiltered exhaled gases from being released into the surrounding environment. In certain embodiments, the slots <NUM> extend vertically or axially along the outside wall of the shroud <NUM>. In such embodiments, standard external filters <NUM>, <NUM> may not completely cover the stots <NUM>; however, proprietary external filters may be configured to mate with the shroud <NUM> so as to completely cover the vertically extended slots <NUM>.

<FIG> illustrate embodiments of the exhalation port <NUM> that employ leak paths <NUM> on the shroud <NUM> by having a plurality of alternating recessed strips <NUM> and ridges <NUM> on the wall of the shroud <NUM>. The recessed strips <NUM> and the ridges <NUM> can start from the outer surface <NUM> of the shroud <NUM> and extend toward the centre portion <NUM>. The recessed strips <NUM> and/or the ridges <NUM> can reach the centre portion <NUM> or stop between the outer surface <NUM> of the shroud <NUM> and the centre portion <NUM>. Like the notches <NUM> and the slots <NUM> described above, the leak paths <NUM> help prevent the vent holes <NUM> from being blocked when an opening defined by the outer surface <NUM> of the shroud <NUM> is covered up by mistake. For example, the shroud <NUM> can be covered up when a <NUM> female cap (not shown) or a nebulizer (not shown) is mistakenly connected to the <NUM> male taper at the outside surface <NUM> of the shroud <NUM>. The shroud <NUM> can also be covered up when the external filter <NUM>, <NUM> (as shown in <FIG>) that is connected to the <NUM> male taper at the outside surface <NUM> of the shroud <NUM> becomes blocked or clogged. For example, the filter <NUM>, <NUM> can become clogged with particulate matters. The leak paths <NUM> allow the exhaled gases to be expired or leaked out via the leak paths <NUM> formed in the shroud <NUM>. Allowing the exhaled gases to escape from the leak paths <NUM> can reduce the amount of dead space where CO<NUM> gases can accumulate, reduce the build-up of CO<NUM> gases in the mask, and beneficially reduce the rebreathing of exhaled gases by the patient. In the illustrated embodiment, the coupling between the <NUM> female connection of the cap, the nebulizer, or the external filter <NUM>, <NUM>, and the <NUM> male taper at the outer surface <NUM> of the shroud <NUM> is not airtight. An inner wall of the <NUM> female connection of the cap, the nebulizer, or the external filter <NUM>, <NUM>, can contact an outer wall of the ridges <NUM>, resulting in the leak paths <NUM> being formed between the inner wall of the <NUM> female connection of the cap, the nebulizer, or the external filter <NUM>, <NUM>, and an outer wall of the recessed strips <NUM>. The exhaled gases from the vent holes <NUM> can escape to the surrounding environment through the leak paths <NUM> to reduce the amount of dead space where CO<NUM> gases can accumulate and the build-up of CO<NUM> gases in the mask so that the patient will not rebreathe too much CO<NUM> when the shroud <NUM> is covered up in circumstances described above. The alternating recessed strips <NUM> and ridges <NUM> also serve to reduce the chance of inappropriate use of the exhalation port <NUM> by differentiating the shroud <NUM> from a regular <NUM> male taper to indicate that it is not to be used in a dual-limb NIV breating circuit.

The leak paths <NUM> can be formed in variety of ways. In some embodiments, the recessed strips <NUM> can be formed by cutting out portions of an outer wall of the shroud <NUM>. In some embodiments, the ridges <NUM> can be affixed to the outer wall of the shroud <NUM> by, for example, adhesives, welding, or other methods known in the art. In some embodiments, the exhalation port <NUM> is formed by a molding operation. Similarly, the recessed portions <NUM> and the ridges <NUM> can also be formed by the molding operation using an appropriately shaped tool used to mold the exhalation port <NUM>. The exhalation port can be molded from any appropriate thermoplastic, such as polycarbonate.

The dimension, spacing and number of the leak paths <NUM> can vary. In some embodiments, the leak paths <NUM> can have a depth of about <NUM> to about <NUM>. In some embodiments, the leak paths <NUM> can have a depth of about <NUM> to about <NUM>. In some embodiments, the leak paths <NUM> can have a depth of about <NUM>. Sizes of the leak paths <NUM> can be tailored depending on whether there is a heightened need for filtering the exhaled gases. When there is less concern with the exhaled gases being infectious, wider and/or deeper recessed strips <NUM> may be formed on the shroud <NUM> so that more exhaled gases can leave from the leak paths <NUM> without being filtered. When there is more concern with the exhaled gases being infectious, narrower and/or less deep recessed strips <NUM> can be formed on the shroud <NUM> so that less exhaled gases can leave from the leak paths <NUM> without being filtered. The recessed strips <NUM> and/or the ridges <NUM>, and thus the leak paths <NUM>, can be of substantially the same shape, size and/or area, or different shapes, sizes and/or areas. The leak paths <NUM> can have a straight or tortuous path along a length of the shroud <NUM>. A straight path may advantageously reduce airflow resistance of the exhaled gases through the leak paths <NUM>. A straight path can also be cheaper to manufacture. A tortuous path can provide higher airflow resistance when it is desired that more exhaled gases be filtered through the filter <NUM>, <NUM>.

As shown in <FIG>, the shroud can have three recessed strips <NUM> alternating with three ridges <NUM>. As shown in <FIG>, the shroud can have two recessed strips <NUM> alternating with two ridges <NUM>. As shown in <FIG>, the shroud can have four recessed strips <NUM> alternating with four ridges <NUM>. As shown in <FIG>, the shroud can have more than four recessed strips <NUM> alternating with more than four ridges <NUM>. A higher number of the leak paths <NUM> can advantageously produce more stable connection between the shroud <NUM> and the filter <NUM>, <NUM> because points of contact between the ridges <NUM> and the filter <NUM>, <NUM> can be more spread out around the circumference of the shroud <NUM>. A lower number of the leak paths <NUM>, on the other hand, can be manufactured more cheaply than the higher number of the leak paths <NUM>.

The leak paths <NUM> can be equally spaced around the circumference of the shroud <NUM>, or have varying spacings around the circumference of the shroud <NUM>. Equal spacing of the leak paths <NUM> may advantageously provide more stable connection between the shroud <NUM> and the filter <NUM>, <NUM>. Equal spacing of the leak paths may also advantageously produce more uniform airflow through individual leak paths.

As shown in <FIG>, in some embodiments the shroud <NUM> also has a plurality of notches <NUM>. Some or all of leak paths <NUM> and some or all of the notches <NUM> can be aligned. Aligning the leak paths <NUM> and the notches <NUM> can advantageously result in the shorter leak paths <NUM> than when the leak paths <NUM> align with a portion of the outer surface <NUM> that does not have the notches <NUM>. The shorter leak paths <NUM> can produce less resistance for the exhaled gases to escape through the leak paths <NUM>.

Illustrated in <FIG> is a preferred embodiment of the exhalation port <NUM> in which the shroud <NUM> includes four recessed strips <NUM> alternating with four strips <NUM>. The recesses strips <NUM> can have a depth of about <NUM>. Each recessed strip <NUM> can span about <NUM>° of a circle formed by the wall of the shroud <NUM>. Each ridge <NUM> can span about <NUM>° of the circle formed by the wall of the shroud <NUM>. As shown in <FIG>, the recessed strips <NUM> are equally spaced on the circle formed by the wall of the shroud <NUM>. The shroud can further include four notches <NUM>, having a rounded spacing between the notches <NUM>. The notches <NUM> can be spaced equally around the outside surface <NUM> of the shroud <NUM>, and the dimensions of the notches <NUM> are substantially equal to the spacing dimensions between the notches <NUM>. As shown in <FIG>, a center line of the notches <NUM> and a center line of the recessed strips <NUM> can be coincident so that the notches <NUM> align with the recessed strips <NUM>. As shown in <FIG>, a center line of the spacing between the notches <NUM> can also be coincident with a center line of the ridges <NUM>. Having four <NUM>° x <NUM> recessed strips <NUM> equally spaced on the circle formed by the wall of the shroud <NUM> and aligned with the notches <NUM> can advantageously provide increased area for airflow, shorter leak paths <NUM>, and reduced air flow resistance, as well as stable connection between the shroud <NUM> and the filter <NUM>, <NUM>.

In embodiments of the exhalation port connected to the external filters <NUM>, <NUM>, the flow resistance across the filter <NUM>, <NUM> is configured to be small such that most of the exhaled gases still exit from the filter <NUM>, <NUM> instead of through the leak paths <NUM>. In one embodiment, about <NUM>% of the exhaled gases exit from the filter <NUM>, <NUM>. The flow resistance of the exhaled gases through the leak paths <NUM> can be adjusted by adjusting how far the filter <NUM>, <NUM> is plugged in from the outer surface <NUM> toward the centre portion <NUM>. The filter <NUM>, <NUM> can be plugged into the shroud <NUM> with a distance just enough to allow the filter <NUM>, <NUM> to be coupled with the shroud <NUM>. The leak paths <NUM> can therefore be short and have low flow resistance for the exhaled gases to leave from the leak paths <NUM>. In some situations, a higher percentage of the exhaled gases is required to be filtered, such as during a pandemic. The filter <NUM>, <NUM> can then be plugged in as close to the centre portion <NUM> as possible, resulting in the longer leak paths <NUM> and higher flow resistance for the exhaled gases to leave from the leak paths. More exhaled gases can thus leave from the filter <NUM>, <NUM>. In some embodiments, the leak paths <NUM> are located so as to not align with the notches <NUM> so that more exhaled gases exit through the filter <NUM>, <NUM> instead of the leak paths <NUM>.

In some embodiments, the exhalation port <NUM> further includes a proprietary filter connection adapter (not shown). The filter connection adapter can be configured to removably connect the shroud <NUM> to the filter <NUM>, <NUM> so as block the leak paths <NUM> and direct more exhaled gases to exit through the filter <NUM>, <NUM>. In one embodiment, the filter connection adapter comprises alternating patterns of recesses and ridges that are complementary to the alternating ridges <NUM> and recessed strips <NUM> of the shroud <NUM> so that the leak paths <NUM> can be substantially blocked by the filter connection adapter. In other embodiments, the filter connection adapter can have pliant or flexible materials that assume the shape of the leak paths <NUM> when the filter connection adapter is connected between the shroud <NUM> and the filter <NUM>, <NUM>.

<FIG> illustrate various aspects of the vent holes <NUM>, or openings <NUM>. The vent holes <NUM>, or openings <NUM>, provide a passageway for the patient's exhaled gases to exit the breathing circuit. Noise created as the exhaled gases exit the breathing circuit through the exhalation port <NUM> can be a source of distraction for patients. Advantageously, the holes <NUM> are formed and arranged so as to reduce the noise of the exhaled gases. As illustrated in <FIG>, preferably, a depth <NUM> of a hole <NUM> is at least two times an inner diameter <NUM> of the hole <NUM>. This ratio helps to reduce noise. In an embodiment, preferably, the hole depth <NUM> is approximately <NUM>. Additionally, a pitch distance <NUM> - the distance between centers of two adjacent holes <NUM> - is at least four times the inner diameter <NUM> of the hole <NUM>. Again, this ratio helps to reduce noise. According to an embodiment, the pitch distance <NUM> is approximately <NUM>. Preferably, the holes <NUM> all have the same inner diameter <NUM>. In certain embodiments, the holes <NUM> preferably have an inner diameter <NUM> between approximately <NUM> and approximately <NUM>. In certain preferred embodiments, the holes <NUM> are tapered, having an external radius <NUM> at the outer surface of the hole <NUM>. Preferably, the outer radius <NUM> is between approximately <NUM> and approximately <NUM>. Thus, in a preferred embodiment, the hole depth <NUM> is approximately <NUM>, the pitch distance <NUM> between holes <NUM> is approximately <NUM>, the inner diameter <NUM> of the hole <NUM> is approximately <NUM>, and the external radius <NUM> of the hole is approximately <NUM>. In another preferred embodiment, the inner diameter <NUM> of an opening <NUM> is approximately <NUM>, the depth <NUM> of the opening <NUM> is at least approximately <NUM>, the pitch distance <NUM> between adjacent openings <NUM> is at least approximately <NUM>, and the external radius <NUM> of the opening <NUM> is approximately <NUM>.

In a preferred embodiment, the vent holes <NUM> are in a square arrangement including <NUM> holes in which all holes <NUM> are aligned with each other. In this embodiment, not all of the holes <NUM> have a consistent pitch distance <NUM> between adjacent holes <NUM>. As illustrated in <FIG>, <FIG>, and <FIG>, various patterns and arrangements of holes <NUM> can be used to realize the exhalation port <NUM> of the present disclosure. <FIG> illustrate triangular, equal-distance vent hole <NUM> grid patterns having <NUM> and <NUM> holes <NUM>, respectively. <FIG> illustrate square vent hole <NUM> grid patterns having <NUM> and <NUM> holes, respectively. <FIG> illustrate circular, ring-shaped vent hole <NUM> patterns having <NUM>, <NUM>, <NUM>, and <NUM> holes <NUM>, respectively.

<FIG> illustrate various alternative embodiments of the exhalation port <NUM>, demonstrating several of the features of the present disclosure. <FIG> illustrates an embodiment of the exhalation port <NUM> in which the shroud <NUM> is planar, i.e., the shroud <NUM> has no notches <NUM> or slots <NUM> within the wall <NUM> of the shroud <NUM>. In this embodiment, the shroud <NUM> projects straight outward, i.e., normal to the longitudinal axis of the exhalation port <NUM>. The shroud <NUM> includes a <NUM> male taper to interface with an external filter <NUM>.

As discussed above, <FIG> illustrates a an embodiment of the exhalation port <NUM> in which the shroud <NUM> includes notches <NUM> that are spaced equally around the outside surface <NUM> of the shroud <NUM>, and the dimensions of the notches <NUM> are substantially equal to the spacing dimensions <NUM> between the notches <NUM>. Additionally, the elongate body <NUM> is at a reduced length to provide a more compact exhalation port <NUM>. The shroud <NUM> includes a <NUM> male taper to interface with an external filter <NUM>.

<FIG> illustrate alternative embodiments of the exhalation port <NUM> featuring an angled connection <NUM> for the shroud <NUM>. Advantageously, the angled connection <NUM> directs exhaled gasses away from the caregiver and the patient. The angled connection <NUM> can be at any angle, including <NUM> degrees from the elongate body <NUM>. In some embodiments the angled connection <NUM> can be at an angle between approximately <NUM> degrees and <NUM> degrees or at an angle between approximately <NUM> degrees and <NUM> degrees, depending on the orientation from the patient interface. The shroud <NUM> illustrated in <FIG> includes a <NUM> male taper to interface with an external filter <NUM>. The shroud <NUM> illustrated in <FIG> includes a <NUM> male taper to interface with an external filter <NUM>.

<FIG> illustrate various alternative embodiments of the exhalation port <NUM> to which an external filter <NUM>,<NUM> is attached. As previously described, the external filter <NUM>, <NUM> protects the surrounding environment from being exposed to infectious agents that can be present in the patient's exhaled gases. <FIG> show two configurations in which the external filters <NUM>, <NUM> are attached to shrouds <NUM> which extend outward approximately normal (i.e., at a <NUM> degree angle) from the elongate body <NUM> of the exhalation port <NUM>. In <FIG>, the external filters <NUM>, <NUM> have <NUM> female tapers with which to mate with a <NUM> male taper of the shroud <NUM> to establish connection between the external filters <NUM>, <NUM> and the shroud <NUM> of the exhalation port <NUM>.

<FIG> show two configurations in which the external filters <NUM>, <NUM> are attached to shrouds <NUM> which extend outward from the elongate body <NUM> of the exhalation port <NUM> at an angled connection <NUM>. The external filters <NUM>, <NUM> have <NUM> female tapers with which to mate with a <NUM> male taper of the shroud <NUM> to establish connection between the external filter <NUM> and the shroud <NUM> of the exhalation port <NUM>. Of course, a skilled artisan will appreciate that many types, forms and formats of external filters <NUM>, <NUM> can be used with the embodiments of the present disclosure.

Referring now to <FIG>, an embodiment of the disclosed exhalation port <NUM> includes and integrated filter/diffuser. <FIG> shows an exploded view of the exhalation port <NUM>. A main body <NUM> provides the structure onto which a sintered diffuser <NUM> and a top portion <NUM> are assembled to form the exhalation port <NUM>. The main body <NUM> includes a pressure line port <NUM> to couple with a pressure sampling line that connects to the noninvasive ventilator or gases source. When the pressure line port <NUM> is not in use, it may be closed off with a cap (not shown). The main body <NUM> also includes exhalation vents <NUM> through which the patient's exhaled gases may pass. The sintered filter/diffuser <NUM> is made of a plastic material that permits airflow to pass through it. Thus, in operation, the exhaled gases exit through the exhalation vents <NUM> of the main body <NUM> into and through the sintered filter/diffuser <NUM> to exit the breathing circuit and enter the surrounding environment. The top portion <NUM> fits over the main body <NUM> and adjacent the sintered filter/diffuser <NUM>, as illustrated <FIG> in which the exhalation port <NUM> is assembled. Advantageously, the exhalation port <NUM> is effective at reducing noise and draft created by the exhalation of a patient's respiratory gases and filtering the exhaled gases.

<FIG> illustrate another embodiment of an exhalation port <NUM> that includes and integrated filter. <FIG> shows the exhalation port <NUM> in an exploded perspective view. The exhalation port <NUM> includes a top half <NUM>, a bottom half <NUM>, and a filter media <NUM>. The bottom half <NUM> also includes exhalation vents <NUM> through which filtered exhaled gases may pass from the breathing circuit to the surrounding environment. In assembly, the two halves <NUM> and <NUM> can be ultrasonically welded together with the filter media <NUM> positioned between the two halves <NUM> and <NUM>. The assembled exhalation port <NUM> operates in-line, in the breathing circuit. The patient's exhaled gases pass through the filter media <NUM> and are channelled through the port <NUM> to the exhalation vents <NUM>. Advantageously, the exhalation port <NUM> filters infectious material from the exhaled gases via an in-line system, thereby avoiding the need to add structure (such as a shroud <NUM>) to accommodate an external filter <NUM>, <NUM>.

<FIG> illustrate yet another embodiment of an exhalation port <NUM> in which a removable filter/diffuser <NUM>, which is a disk or cap, is inserted within the shroud <NUM>. The removable filter/diffuser <NUM> can be made of sintered plastic, foam, or fabric materials that can reduce the noise associated with exhalation of respiratory gases and permit airflow to pass through it. Thus, in operation, the exhaled gases exit through the vent holes <NUM> into and through the sintered filter/diffuser <NUM> to exit the breathing circuit and enter the surrounding environment. Advantageously, the exhalation port <NUM> provides noise reduction of exhalation gases being expelled from the breathing circuit without increasing adding to the size or volume of the exhalation port <NUM>. The exhalation port <NUM> can also filter the exhaled gases.

<FIG> illustrate another embodiment of an exhalation port <NUM> in which a hinged shroud <NUM> is optional and separately attachable to the exhalation port <NUM>. The exhalation port <NUM> includes most of the elements described with respect to the embodiment of exhalation port <NUM>, including a top portion <NUM>, a center portion <NUM>, and a bottom portion <NUM>, a <NUM> male taper <NUM>, a <NUM> female taper <NUM>, a pressure line port <NUM>, and a plurality of vent holes <NUM>, or openings <NUM>. The exhalation port <NUM> also includes an upper ledge <NUM> and a lower ledge <NUM> which are used to attach the hinged shroud <NUM> to the exhalation port <NUM>. As illustrated in <FIG>, the hinged shroud <NUM> includes two halves, which may be connected by a hinge (not shown for ease of illustration), which are attached to the exhalation port <NUM>. Once assembled, as illustrated in <FIG>, the hinged shroud <NUM> is configured to attach to an external filter <NUM> to the exhalation port <NUM> and to reduce the entrainment of ambient air within the exhalation stream. The hinged shroud <NUM> reduces draft by preventing ambient air from being sucked up into the exhalation air stream. Advantageously, the exhalation port <NUM> provides a simplified form factor for use in circumstances where it is not desired to employ an external filter <NUM> because, for example, the patient does not pose a risk of infection to care providers or others in proximity of the patient's exhaled gases. If the patient subsequently presents a risk of infection, then the hinged shroud <NUM> can be attached to the exhalation port <NUM> to enable attachment of an external filter <NUM>.

<FIG> illustrate another embodiment of an exhalation port <NUM> in which a removable shroud <NUM> is optional and separately attachable to the exhalation port <NUM>. In this embodiment, a shroud connector <NUM> surrounds the vent holes <NUM>. The shroud connector <NUM> is configured to receive a <NUM> female taper of the removable shroud <NUM>. As illustrated in <FIG>, the removable shroud <NUM> mates with the shroud connector <NUM> to secure the removable shroud <NUM> in place. Methods of mating the shroud <NUM> to the shroud connector <NUM> can include, among others, snug-fit and click-on connections, as well as standard medical <NUM> and <NUM> taper connections. Once secured, the removable shroud <NUM> is configured to attach to an external filter <NUM>, <NUM> to the exhalation port <NUM> and to reduce the entrainment of ambient air within the exhalation stream.

Various embodiments of the disclosed exhalation port have been described herein. Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of "including, but not limited to.

Reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in the field of endeavor in any country in the world.

Certain features, aspects and advantages of some configurations of the present disclosure have been described with reference to use by a patient or user. However, certain features, aspects and advantages of the use of the exhalation port as described may be advantageously practiced by other people on behalf of the patient, including medical professionals, medical device dealers, or medical device providers. Certain features, aspects and advantages of the methods and apparatus of the present disclosure may be equally applied to usage by other people.

Claim 1:
An exhalation port (<NUM>) for noninvasive ventilation therapy comprising:
an elongate body (<NUM>), said elongate body (<NUM>) being hollow and defining a lumen (<NUM>) to carry a flow of gases;
a top portion (<NUM>), a centre portion (<NUM>), and a bottom portion (<NUM>);
a plurality of openings (<NUM>) arranged on a portion (<NUM>) of the elongate body, the plurality of openings (<NUM>) configured to vent gases through the openings (<NUM>);
a pressure port (<NUM>) extending outward from the elongate body (<NUM>), the pressure port (<NUM>) configured to couple with a pressure sampling line that connects to a noninvasive ventilator;
a shroud (<NUM>) extending from the elongate body, the shroud (<NUM>) surrounding one or more of the plurality of openings (<NUM>);
the shroud (<NUM>) comprising an outer wall and an outer surface (<NUM>);
the shroud (<NUM>) being removable from the elongate body;
wherein a plurality of alternating recessed strips (<NUM>) and ridges (<NUM>) are provided on the outer wall of the shroud (<NUM>), the plurality of alternating recessed strips (<NUM>) and the ridges (<NUM>) starting from the outer surface (<NUM>) of the shroud (<NUM>) and extending toward the center portion (<NUM>); and
wherein the exhalation port (<NUM>) is arranged to removably connect in-line with a circuit for delivering gases to a patient.