Patent Description:
Known ostomy bags include a filter arranged at a wall of the bag to vent and deodorize gas from inside the bag to the atmosphere. However, the filter may become partially or completely occluded, for example, by effluent within the bag. An occluded filter may restrict venting of the gas through the filter and pressure may accumulate in the bag. This may lead to undesirable ballooning of the bag.

<CIT> discloses an ostomy pouch used by colostomy and ileostomy patients to receive bodily waste from a stoma the pouch comprises a bag (<NUM>), an inlet aperture (<NUM>) surrounded by an adhesive attachment collar (<NUM>), and a valve assembly (<NUM>) for venting gas from the bag. The valve means comprises an outer resilient frusto-conical diaphragm (<NUM>) integrally formed with a resilient inner cylindrical core (<NUM>) having a slot (<NUM>) cut in its wall. By squeezing the outer diaphragm (<NUM>) the inner core (<NUM>) is distorted to cause the slot (<NUM>) to open and release gas from within the bag, through a filter (<NUM>) to atmosphere. The valve assembly (<NUM>) enables the bag to be vented at will and thus provides user control to prevent ballooning and pancaking of the bag.

<CIT> discloses a colostomy bag having a device for filtration and controlled discharge of malodorous intestinal gases and having a separate filter chamber (<NUM>) which is to receive a filter material (<NUM>) and which has a gas outlet port (<NUM>) leading into the open and is connected via a gas inlet port (<NUM>), closed by means of a manually operable valve (<NUM>), to the interior (<NUM>) of the bag receiving the intestinal excretions, characterized in that the device for filtration and controlled discharge of the intestinal gases is integrated into the bag as a result of the filter chamber (<NUM>) being provided in the bag and being directly connected via the valve (<NUM>) to the remainder of the interior (<NUM>) of the bag.

<CIT> discloses an ostomy pouch in which a flexible, shape-recoverable plastic dome is secured internally to a wall of the pouch over a vent opening. A peripheral portion of the dome spaced from the apex is provided with at least one slit therethrough traversing a radially and axially extending plane of the dome. The slit is curved or arched towards the apex and defines outer and inner lips that normally have their opposing edges in juxtaposition to restrain the escape of gases from the pouch but permit such escape in quantity when the apical portion of the dome is depressed (by axially squeezing the dome). The lips advantageously have beveled opposing surfaces with the surface of the outer lip generally facing towards the vent opening and that of the inner lip generally facing away from the vent opening. A stop element projects from the apical portion within the dome and is engagable with a deodorizing gas filter located at the base of the dome to limit the extent of deformation of the dome, and to prevent occlusion of the filter by the reverted apical portion of the dome, when the dome is pressed inwardly to open the valve.

Accordingly, it is desirable to provide an ostomy appliance, such as an ostomy pouch, having a filter assembly configured to provide for bypass venting of gas to the atmosphere.

In one embodiment, an ostomy appliance includes a pouch wall defining at least a portion of a collection chamber configured to collect and store effluent from a stoma, an inlet formed in the pouch wall configured to be secured around the stoma and a filter assembly including filter, a valve and a bypass venting chamber extending between the filter and the valve. The filter includes an active gas inlet section configured to receive gas from the collection chamber, a bypass gas inlet section configured to receive gas through the valve, and a filter outlet section for exiting gas to the atmosphere.

In one embodiment, the valve may be operable between a closed configuration in which gas flow from the collection chamber to the bypass venting chamber through the valve is restricted, and an open configuration in which the collection chamber and the bypass venting chamber are in fluid communication with one another such that gas may be received in the bypass venting chamber from the collection chamber through the valve. In one embodiment, the valve may be a check valve. In one embodiment, the valve may include a resilient valve body and a flow control portion movable between a closed condition corresponding to the closed configuration of the valve and an open condition corresponding to the open configuration of the valve. In one embodiment, the valve body may urge the flow control portion to the closed condition. In one embodiment, the filter maybe at least partially disposed in the bypass venting chamber. In one embodiment, the bypass venting chamber may include at least a portion of the pouch wall. In one embodiment, the filter may include hydrophobic membrane.

<FIG> is a plan view showing a portion of an ostomy appliance <NUM> having a filter assembly <NUM> with a bypass venting chamber <NUM>, according to an embodiment. The ostomy appliance <NUM> may be an ostomy pouch configured to be secured to a user in a known manner. The ostomy appliance <NUM> includes a pouch wall <NUM> defining at least a portion of a collection chamber <NUM> within the ostomy appliance <NUM> configured to receive and store effluent discharged from a stoma. A stoma inlet opening <NUM> is formed in the pouch wall <NUM> and is configured to be fitted around the stoma when the ostomy appliance is secured to the user.

<FIG> is a perspective view of the filter assembly <NUM> according to an embodiment. <FIG> is a cross-sectional side view of the filter assembly <NUM> according to an embodiment. The filter assembly <NUM> includes a filter <NUM> and a valve <NUM> fluidically connected to one another by the bypass venting chamber <NUM>. The bypass venting chamber <NUM> may be formed, for example, by a housing, barrier, membrane or other similar structure connected to and extending between the filter <NUM> and the valve <NUM>. In one embodiment, at least a portion of the bypass venting chamber <NUM> may be formed by the pouch wall <NUM>.

In one embodiment, the filter <NUM> may be a porous, gas-permeable filter configured to deodorize a gas flowing through the filter <NUM>. Examples of such filters include known carbon filters commonly used in ostomy appliances. The filter <NUM> may include a hydrophobic membrane so that the filter <NUM> is substantially liquid impermeable. In one embodiment, the filter <NUM> may be at least partially disposed in the bypass venting chamber <NUM>. The filter <NUM> includes a filter outlet section <NUM> through which a filtered gas may exit and be released to the atmosphere.

The valve <NUM> includes a valve body <NUM> and a flow control portion <NUM> configured to be operated between a closed condition and an open condition. In one embodiment, the valve <NUM> may be a check valve. In one embodiment, the valve body <NUM> may be a substantially resilient body, and the flow control portion <NUM> may be a valve slit formed in the valve body <NUM>.

Referring to <FIG>, the filter <NUM> further includes an active gas inlet section <NUM> and a bypass gas inlet section <NUM>. The filter <NUM> is configured to receive unfiltered gas from the collection chamber <NUM> through the active gas inlet section <NUM>. The filter <NUM> is also configured to receive unfiltered gas from the bypass venting chamber <NUM> through the bypass gas inlet section <NUM>.

The valve <NUM> is operable between a closed configuration in which flow of unfiltered gas from the collection chamber <NUM> into the bypass venting chamber <NUM> through the valve <NUM> is substantially prevented, and an open configuration in which flow of unfiltered gas from the collection chamber <NUM> into the bypass venting chamber <NUM> through the valve is permitted. In one embodiment, the valve <NUM> may be actuated, i.e., moved from the closed configuration to the open configuration, by applying a force to the valve body <NUM>, for example, by manually squeezing the valve body <NUM>, by a gas pressure within the collection chamber <NUM>, or by a specific actuating tool on the valve <NUM> or a tool configured for use with the valve <NUM>. In one embodiment, the valve <NUM> may be moved from the open configuration to the closed configuration by a applying a force in a direction opposite to that described above for moving the valve to the open configuration. In one embodiment, the valve <NUM> may be resiliently urged to one of the open configuration or the closed configuration such that the valve <NUM> is normally open or normally closed.

In one embodiment, the valve body <NUM> is a bulb-shaped portion made of a resilient material and the flow control portion <NUM> is a valve slit resiliently urged to a closed condition, corresponding to the closed configuration of the valve <NUM>. A force, such as a manual squeezing force, may be applied to the valve body <NUM> to move the valve <NUM> to the open configuration by moving the flow control portion <NUM> to the open condition. The valve <NUM> may be returned to the closed configuration by releasing the squeezing force, allowing the flow control portion <NUM> to return to the closed condition under the resiliency of the valve body <NUM>.

It will be appreciated that the present disclosure is not limited to the example described above and shown in <FIG> and <FIG>. For example, the force applied to the valve <NUM> may be a one-way directional force, for example, from a gas pressure in the collection chamber <NUM>. The valve body <NUM> may elastically deform to move the flow control portion <NUM> to the open condition if the force exceeds a predetermined value. The flow control portion <NUM> may return to the closed condition when the force, e.g., gas pressure, in the collection chamber <NUM> falls below the predetermined value.

The filter assembly <NUM> may be installed or formed in the ostomy appliance <NUM> at the pouch wall <NUM>. According to one embodiment, in an active venting state, unfiltered gas in the collection chamber <NUM> flows toward the filter <NUM> along active gas path AGP and is received in the filter <NUM> through the active gas inlet section <NUM>. The gas may then flow through the filter <NUM> along filter gas path FGP where the gas is filtered (i.e., deodorized). The filtered gas may then exit the filter <NUM> through the filter outlet section <NUM> to the atmosphere along exit gas path EGP.

Occlusion of the active gas inlet section <NUM> of the filter <NUM> by effluent in the collection chamber <NUM> may restrict flow of gas into the filter <NUM> through the active gas inlet section <NUM> and cause gas pressure to accumulate in the collection chamber <NUM>. To vent gas from the collection chamber <NUM>, the valve <NUM> may be actuated to the open configuration so that the bypass venting chamber <NUM> is in fluid communication with, and receives unfiltered gas from, the collection chamber <NUM> through the valve <NUM>. For example, with the valve <NUM> in the open configuration, i.e., with the flow control portion <NUM> in the open condition, the unfiltered gas from the collection chamber <NUM> may flow through the flow control portion <NUM> into the valve <NUM> along valve gas path VGP. The unfiltered gas may then flow into the bypass venting chamber <NUM> to the filter <NUM> along bypass gas path BGP, and into the filter <NUM> through the bypass gas inlet section <NUM>. The gas may then flow through the filter <NUM> along the filter gas path FGP and exit the filter <NUM> through filter outlet section <NUM> to the atmosphere along the exit gas path EGP in the manner described above.

Accordingly, in the examples above, undesirable gas pressure in the ostomy appliance <NUM> resulting from an occluded filter inlet section may be substantially relieved or avoided by operation of the valve <NUM>, which allows unfiltered gas to bypass the occluded section of the filter <NUM>.

<FIG> is a perspective view of an outer surface of the ostomy appliance <NUM> having the filter assembly <NUM> according to an embodiment. <FIG> is a cut-away perspective view showing an interior of the ostomy appliance <NUM> having the filter assembly <NUM> according to an embodiment. In one embodiment, the filter assembly <NUM> is disposed relative to the pouch wall <NUM> such that at least the bypass venting chamber <NUM> and the valve <NUM> are disposed within the pouch wall <NUM>. Thus, in one embodiment, the valve <NUM> may be operated by applying a force to pouch wall <NUM> in the vicinity of the valve body <NUM> such that the force is transmitted to the valve body <NUM>. For example, as shown in <FIG>, a force may be applied to a first section <NUM> on an outer surface of the pouch wall <NUM> to actuate the valve <NUM>.

<FIG> shows the valve <NUM>, including a valve body <NUM> formed as a bulb-shaped portion, according to an embodiment.

In some embodiments, the filter assembly <NUM> may include a bulb check valve <NUM>. Active venting of gas from inside the ostomy appliance to the atmosphere may be accommodated through a filter having a hydrophobic membrane. The filter assembly <NUM> may include a bypass of the interior hydrophobic membrane in case of occlusion. In an embodiment, the bypass may be performed by manual operation of the valve <NUM>. In this manner, gas may be vented through the filter along different path to bypass the occluded section.

In an alternate embodiment, the filter assembly <NUM> may include portions of the pouch wall <NUM>, i.e., pouch surfaces. The pouch surfaces <NUM> may be specifically contoured for each of access to operate the valve <NUM>, for example, to squeeze the bulb portion. The filter assembly may be attached to the ostomy appliance using known techniques, e.g., heat sealing.

It is understood that the relative directions described above, e. g, "upward," "downward," "upper," "lower," "above," "below," are used for illustrative purposes only and may change depending on an orientation of the ostomy pouch and/or the patient. Accordingly, this terminology is non-limiting in nature. In addition, it is understood that one or more various features of an embodiment above may be used in, combined with, or replace other features of a different embodiment described herein.

Claim 1:
An ostomy appliance (<NUM>) comprising:
a pouch wall (<NUM>) defining at least a portion of a collection chamber (<NUM>) configured to collect and store effluent from a stoma;
an inlet (<NUM>) formed in the pouch wall configured to be secured around the stoma; and
a filter assembly (<NUM>) comprising a filter (<NUM>), a valve (<NUM>) and a bypass venting chamber (<NUM>) extending between the filter (<NUM>) and the valve (<NUM>),
wherein the valve (<NUM>) comprises:
a closed configuration in which gas flow from the collection chamber (<NUM>) to the bypass venting chamber (<NUM>) through the valve (<NUM>) is restricted; and
an open configuration in which the collection chamber (<NUM>) and the bypass venting chamber (<NUM>) are in fluid communication with one another such that gas is received in the bypass venting chamber (<NUM>) from the collection chamber (<NUM>) through the valve (<NUM>),
wherein the filter (<NUM>) comprises an active gas inlet section (<NUM>) configured to receive gas from the collection chamber (<NUM>); and
a filter outlet section (<NUM>) for exiting gas to the atmosphere;
characterised in comprising a bypass gas inlet section (<NUM>) configured to receive gas from the bypass venting chamber (<NUM>), wherein gas enters the bypass venting chamber (<NUM>) from the collection chamber (<NUM>) through the valve (<NUM>) in the open configuration; and
in that the filter assembly (<NUM>) is configured to allow gas from the collection chamber (<NUM>) to flow toward the filter (<NUM>) through the active gas inlet section (<NUM>) in an active venting state with the valve (<NUM>) in the closed configuration, and wherein when the active gas inlet section (<NUM>) becomes occluded, actuating the valve (<NUM>) transitions the valve (<NUM>) from the closed configuration to the open configuration allowing gas from the collection chamber (<NUM>) to flow toward the filter (<NUM>) through the bypass gas inlet section.