WO2017001846A1

WO2017001846A1 - An ostomy pouch including a non-return valve

Info

Publication number: WO2017001846A1
Application number: PCT/GB2016/051949
Authority: WO
Inventors: Paul Stephen Bird
Original assignee: Pelican Healthcare Limited
Priority date: 2015-06-29
Filing date: 2016-06-29
Publication date: 2017-01-05
Also published as: GB201511336D0; GB201721784D0; GB2556498A

Abstract

An ostomy pouch comprises first and second walls defining a storage chamber for receiving solid and/or liquid bodily waste matter. The pouch includes an opening for receiving bodily waste matter to be stored in the pouch. A waste channel is located within the storage chamber of the pouch between the first and second walls that is formed from a flexible material. The waste channel has an inlet sealed around the opening of the pouch and an outlet at its lower end. The waste channel channels solid and/or liquid matter from the opening into the storage chamber through the waste channel outlet. The free end of the waste channel is reconfigurable between an open configuration in which bodily waste is able to exit the outlet into the storage chamber and a closed configuration in which waste within the storage chamber is prevented from entering the waste channel through the outlet, the closed configuration being a folded and or collapsed configuration.

Description

AN OSTOMY POUCH I NCLUDI NG A NON-RETURN VALVE

The present invention relates to an ostomy pouch, and in particular an ostomy pouch having a non-return arrangement for preventing bodily waste matter contained within the pouch from flowing back to the inlet opening.

An ostomy is surgery during which an opening, is created connecting a portion of the body cavity to the environment outside the body. Ostomy surgery may be used to treat diseases of both the digestive or urinary systems. There are numerous different ostomy surgeries, examples of the more common of which include colostomy, ileostomy and urostomy. Colostomy is a procedure in which a portion of the colon is removed, and the remaining colon is brought to the abdominal wall and attached to the stoma, bypassing the rectum and anus. An ileostomy similarly diverts the small intestine through an opening in the abdomen. A urostomy diverts urine away from a diseased or defective bladder. The bladder is bypassed by attaching to the stoma the tubes that carry urine to the bladder. The end section of the ureter or colon that protrudes through the abdominal wall is referred to as the stoma.

Following an ostomy procedure a means is required for collecting from the waste the stoma, which may be solids or liquids depending on the ostomy procedure. For ostomy procedures such as a colostomy, ileostomy and/or urostomy ostomy pouches are provided that connect to the stoma to collect the waste. Ostomy pouches for this purpose typically comprise a plastic collection bag, and a mounting plate, commonly referred to as an ostomy flange, that secures the bag to the patient and provides an air and water tight seal about the stoma.

Depending on the frequency with which the pouch needs to be emptied, it may be provided with a drainage system. For urostomy pouches, which will contain only liquid, the drainage arrangement will typically comprise a valve that permits the liquid to be drained from the pouch via an outlet nozzle. For solid waste it is known to provide an open ended pouch having a resealable neck that may be folded to seal the bag using a Velcro closure or clip.

For certain conditions it is necessary to perform both a colostomy and urostomy on the patient. One example is a pelvic exenteration, in which all of the organs within the pelvic cavity are removed. In such circumstances it is known to perform what is referred to as a 'double-barrelled wet colostomy' (DBWC) wherein a single stoma is created through which both the urinary and faecal matter passes. It has been found that this procedure reduces patient morbidity compared with procedures in which two stomas are created, with fewer conduit and anastomotic leaks also being experienced than are seen with separate urinary and faecal diversions. DBWC has also been shown to increase patient comfort and result in a decrease in the length of hospital admission, and a reduction operating times.

The single stoma resulting from a DBWC requires the ostomy pouch to be able to effectively handle both urinary and faecal matter in a safe and secure manner. Associated problems in this regard are firstly the increased volume of waste matter that is produced by the stoma and how this is handled; the volume of liquid produced over time is far greater than the volume of solids, so the mixed use pouch fills far quicker than a solids only bag. There is also an elevated risk of cross contamination, and in particular and increased risk of contamination of the urinary tract by faecal matter, particularly as the bags fill and/or and compressed or reoriented causing waste matter in the bag to flow to the stoma opening and into contact with the exposed stoma.

Currently the increased volume is simply handled by the use of larger volume 'high output' bags. However, the use of such bags is impractical and undignified for the user as the bags are difficult to carry and to conceal. The emptying of waste from a high output is also more difficult and likely to result in leakage or spillage. In addition, such large volume bags remain prone to the risk of waste flowing back to the stoma due to over filling or reorientations and/or compression. It is therefore desirable to provide an improved ostomy pouch which addresses the above described problems and/or which offers improvements generally.

According to the present invention there is provided an ostomy pouch as described in the accompanying claims.

In an embodiment of the invention there is provided an ostomy pouch comprising first and second walls defining a storage chamber for receiving solid and/or liquid bodily waste matter. The pouch includes an opening for receiving bodily waste matter to be stored in the pouch. A waste channel is located within the storage chamber of the pouch between the first and second walls. The waste channel is formed from a flexible material and has an inlet sealed at least partially around the opening of the pouch and an outlet provided at a free end spaced from the opening. The waste channel is configured to channel solid and/or liquid matter from the opening into the storage chamber through the outlet. The free end of the waste channel is reconfigurable between an open configuration in which bodily waste is able to exit the outlet into the storage chamber and a closed configuration in which waste within the storage chamber is prevented from entering the waste channel through the outlet. In this way the waste channel forms a non-return va lve that permits solid and liquid bodily waste matter to pass from the stoma extending through the opening into the storage chamber, while preventing matter contained within the storage chamber from passing back into the secondary chamber and flowing back to the inlet opening. This is particularly advantageous where the pouch is used to contain contaminated or infectious material, the non-return valve preventing the accidental release of said material once it has been passed into the storage chamber. Furthermore, in the case of ostomy care, the non-return valve prevents waste matter from passing back to the opening where it may come into contact with the stoma, thereby minimising the risk of stoma infection. The free end of waste channel at which the outlet is located is freely movable relative to the first and second walls such that the lower end is able to deform upon contact with solid or liquid matter contained within the storage chamber to prevent said solid or liquid matter from entering the secondary chamber. The configuration of the waste channel is such that when waste matter is not passing through the channel the surface adhesion between the two films forming the channel causes the outlet to close. This in itself may be sufficient to prevent waste matter in the storage chamber from entering the waste channel through the outlet. In addition, the free end is freely movable, and as the waste matter contacts the free end it deforms and this deformation further acts to close the outlet and seal the waste channel from the storage chamber.

Preferably the first and second walls of the storage chamber are sealed to each other around their peripheral edges and the waste channel has a peripheral edge that is spaced inwardly of the peripheral edges of the first and second walls. The peripheral edge of the waste channel is inwardly spaced from the peripheral edges of the first and second walls, and specifically inwardly spaced from the bonding region about the periphery of the pouch such so that the waste channel is not bonded to the pouch by the peripheral bonding region, with the peripheral edge of the waste channel being independently movable relative to the pouch. Locating the peripheral edge of the waste channel inboard of the peripheral bonding region of the pouch also advantageously optimises bonding of the front and rear walls.

The opening is preferably formed in the first wall of the pouch and the waste channel is sealed around the opening of the pouch by a bonding region that bonds the waste channel to the first wall. The waste channel is secured to the pouch by the bonding region only. The annular bonding region surrounding the opening is the only point at which the waste channel, which defines the non-return valve, is attached to the walls of the pouch, with the waste channel being attached to the rear wall only. This optimises the flexibility of the waste channel within the valve, and also simplifies manufacture. Specifically the waste channel is sealed in a first RF welding step and then bonded to the rear wall in a second thermal welding step. The free end of the secondary chamber preferably forms a flap that is movable between an unfolded condition in which matter within the waste channel is able to pass through the outlet, and a folded condition in which the secondary chamber is sealed preventing matter from within the storage chamber from entering the secondary chamber. The formation of a fold creates a seal line along the fold that closes and seals the waste channel. This simple flap arrangement is effective in preventing the passage of matter back into the secondary chamber, while also being easy and cheap to manufacture.

The outlet is preferably located at the free end which is located at the lower end of the waste channel, the lower end being arranged in use below the opening. I n this way, waste matter entering the secondary chamber passes to the outlet under gravity.

The first and second walls preferably comprise first and second flexible waterproof films sealed to each other around their peripheral edges to form said storage chamber, and the waste channel is formed from third and fourth flexible films sealed to each other along their side edges. Forming the secondary chamber from plastic films allows the non-return valve arrangement to be produced at very low cost.

The third and fourth films are preferably sealed at least partially along their upper edges. In this way, the secondary chamber is sealed entirely other than at the outlet, ensuring that the outlet is the only way for waste matte to pass out of the waste channel, and ensuring that there is no other way for waste matter to pass back into the chamber.

The third and fourth films are preferably sealed to the first and second films along their upper edges. This simplifies the manufacturing processing by sealing the outer walls of the bag, and the upper edge of the non-return valve in a single thermal welding step.

The first and second flexible sheets of the waste channel preferably have adjacent inner surfaces having material properties suitable for radio frequency welding and external surfaces having material properties suitable for thermal welding. The first and second sheets may be formed from a laminate material having polythene layer and a polyester later, with the first and second sheets being arranged such that polyester layers are inwardly facing within the interior of the waste channel and the polythene layers are outwardly facing on the exterior surfaces of the waste channel. The peripheral edges of the waste channel are preferably bonded by radio frequency welding and the waste channel is bonded to the first wall of the pouch by thermal welding. As the interior surfaces of the waste channel will not thermally bond to each other, this arrangement advantageously enables the waste channel to be thermally welded to the rear wall and the mounting plate by application of a thermal welding tool to the upper layer of the waste channel without the inner surfaces of the waste channel becoming bonded to each other. This arrangement thereby simplifies manufactures and obviates the requirement for placing a barrier layer, such as PTFE or Teflon ^® layer between the sheets of the waste channel to prevent them from thermally welding to each other.

The waste channel may be formed as a sleeve, open at both ends, with the upper end being sealed in the above descried thermal welding step. The sleeve is preferably formed from two plastic films sealed together along their side edges by thermal welding or any other suitable means. Alternatively the waste channel may also be sealed along its upper edge.

Preferably the waste channel tapers inwardly towards the outlet. As such the waste channel functions as a funnel, channelling the waste matter to the outlet. This

arrangement also advantageously limits the width of the outlet, thereby minimising the risk of waste matter passing back through the outlet.

The opening may define a stoma opening. The pouch may further comprise a mounting disc having an aperture formed therein defining the stoma opening. The third film forms a seal around the stoma opening such that matter entering the pouch via the opening enters directly into the waste channel and is sealed from the storage chamber. The third film is preferably thermally welded to the mounting disc, the thermal weld forming an annular seal spaced radially outwards from the opening. The third film includes an opening that is preferably arranged concentrically with the stoma opening, and the third film is thermally welded to the mounting disc along the edge of the opening.

The first film is also preferably thermally welded to the mounting disc along a common seal with the third film. The term 'welded to' or 'secured to' means relative to and does not require either film to be welded directly to the mounting plate. For example, the third film may welded directly to the mounting inwardly of the opening of the first film, or the first film may be thermally welded directly to the mounting plate and the third film welded to the first film to secure it relative to the mounting plate.

The present invention will now be described by way of example only with reference to the following illustrative figures in which:

Figure 1 is a rear view of an ostomy pouch according to an

embodiment of the present invention; and

Figure 2 is a side section view of the arrangement of Figure 1.

Referring to Figure 1, there is provided an ostomy pouch 1 formed from two opposing films of flexible waterproof material defining a front wall 2 and a rear wall 4 of the pouch 1. The front wall 2 and rear wall 4 are sealed at their common peripheral edges 6 to form a cavity defining a liquid receptacle for receiving liquid and solid waste. The sealing may be effected by welding such as thermal or RF welding, bonded such as by adhesion, or by any other suitable means. The front and rear walls 2,4 are sealed around their entire peripheral edge with the exception of the lower edge 7 which remains unsealed to define an opening that is described in further detail below. A mounting flange 8 is secured to the rear wall 4 of the pouch 1. The mounting flange preferably comprises a foam disc and a hydrocolloid skin barrier layer, which are adhered together to form a flexible pad. The mounting flange may a planar disc or may include a convex central portion. Where the mounting flange includes a convex central portion it may further include a plastic mounting plate which provided a stiffer substrate to which the foam and hydrocolloid layers confirm, enabling the convex profile to be maintained.

The mounting flange 8 includes an aperture 10 arranged substantially centrally on the mounting flange 8. The rear wall 4 of the pouch 1 is sealed to the front face 12 of the mounting flange 8 at a sealing region 14. The term 'front' refers to a face which in use faces away from the body of the user, and the term 'rearward' refers to a face which in use faces towards the user. The bonding region 14 between the rear wall 4 and the front face 12 is annular and surrounds the aperture 10 and is preferably concentric therewith. An aperture 16 is formed in the rear wall 4 having an edge 18 that aligns with the inner edge of the sealing region 14 such that the rear wall 4 is sealed to the mounting plate 8 around the periphery of the aperture 16. A region of the mounting plate 8 extends radially inwards from the inner edge of the aperture 18 to the edge of the aperture 10 that is exposed to the interior of the pouch 1 at the front surface 12 of the mounting flange 8.

The aperture 10 in the mounting flange 8 defines an opening into the pouch 1 through which a stoma is extended in use. The rear surface 20 of the mounting plate 8 includes a hydrocolloid adhesive layer for bonding the mounting plate 8 to the skin of the patient, the adhesive layer providing a barrier seal extending from the peripheral edge 22 of the mounting plate 8 to the aperture 10. In this way, when the stoma is extending through the aperture 10 in use a barrier seal is created between the mounting plate 8 and the skin of the patient that is airtight and watertight from the edge of the aperture 10 outwardly, thereby sealing the contents of the bag from the external environment.

The mounting flange 8 is arranged towards the top of the pouch 1 such that when the pouch 1 is arranged vertically in use a significant portion of the volume of the pouch 1 is arranged beneath the opening 10. In use the stoma extends through the opening 10 and waste matter from the stoma is passed directly into the pouch 1. The waste matter passes downwardly from the aperture 10 into the collection pouch 1 between the sealed inner surfaces of the front 2 and rear 4 walls of the pouch 1.

An opening 24 is formed at the lower end 8 of the pouch 1 by the peripheral edges of the front 2 and rear 4 walls which are sealed together at the ends of the lower edges 7 only, with the length of the lower edges 7 remaining unsealed. The pouch 1 narrows towards the lower end forming a necked portion 23. Stiffening strips 26 are provided on the outer surfaces of the front 2 and rear 4 walls adjacent the lower edge 7. The stiffening strips 26 enable a user to more easily open the opening 24 should be inner surfaces of the front 2 and rear 4 walls stick together at this location. The contents of the pouch may be emptied through the opening 24 at the bottom plate of the bag by unfurling the opening 24 over a suitable disposal receptacle. To close the opening 24 the dual plies of the front 2 and rear 4 flexible walls are held together and the neck 23 is folded upwardly in one or preferably two folding operations. The folds of the neck 23 create a seal between the main cavity of the pouch 1 and the opening 24 thereby retaining the contents of the pouch 1 and preventing them from exiting the opening 24. Closure tabs 28 are provided including hook and eye fastener sections are their ends that fold and secure to a corresponding hook and eye fastener strip on the neck 23 that locates adjacent the tabs 28 when the neck 23 has been folded to a sealed condition.

A non-return valve 30 is provided within the pouch 1. The non-return valve is arranged to channel waste matter from the stoma opening 10 into the main chamber of the pouch 1, and to prevent waste matter that has passed into the main chamber of the pouch 1 from returning back to the stoma opening 10. As shown in Figure 2 the non-return valve is comprised of a pair of flexible film layers including a front film 32 and a rear film 34. The front 32 and rear 34 films each have a corresponding frusto conical shape that tapers from an upper edge 36 to a narrower lower edge 38. The front 32 and rear 34 sheets are sealed together at their upper edges 36. The films 32,34 also include side edges 40, as shown in Figure 1. The side edges 40 are also sealed together. The front 32 and rear 34 sheets are preferably formed of a plastic material having a first surface, the material properties of which allow the material to be joined by Radio Frequency (RF) welding (also known as dielectric sealing or high frequency welding) and a second surface having material properties which allow the material to be joined by thermal welding. Preferably the front and rear sheets are formed from a laminate material comprising polyester and polythene. The polyester (also referred to as polyethylene terephthalate) layer of the polyester/polythene (PET/PE) laminate is RF weldable and the polythene (PE) layer is suitable for thermal welding. The front and rear sheets 32,34 are arranged with the PET layers facing each other within the interior of the non-return valve 30, and the PE layers at the external outwardly facing sides. To seal the edges of the non-return valve, the front 32 and rear 34 sheets are placed together and arranged such that the first RF weldable surfaces are facing each other. In this

arrangement the edges may be sealed together using RF welding which causes the first surfaces to bond to each other. The front and rear sheets 32,34 are sealed by RF welding along the side edges 40 and their upper edge 36, with the lower edge 38 remain unsealed, to create a pre-formed valve.

The rear sheet 34 or the non-return valve 30 includes an aperture 42 that aligns with and preferably has the same diameter as the aperture 18 of the rear wall 4. During assembly the non-return valve 30 is on the rear wall 4 and arranged relative to the rear wall 4 such that the apertures 42,18 align. The mounting plate 8 is arranged beneath the rear wall 4 in alignment with the apertures 42,18. The rear wall 4 and the rear sheet 34 of the nonreturn valve 30 are then sealed to the inner surface of the mounting flange 8 around the perimeter of the aperture 42 by thermal welding. The thermal welding tool is applied from above to the front sheet 32 of the non-return valve 30. Due to the inner surfaces being formed of an RF weldable material, the first surfaces of the front 32 and rear 34 sheets to not bond to each other during this thermal welding step. Instead, the heat is transferred through the non-return valve 30 to bond the rear wall 4 and the rear sheet 34 of the non-return valve 30 to each other and the inner surface of the mounting flange 8 in an annular seal. This welding step thereby seals the non-return valve 30 to the pouch 1 and about the stoma opening 10. The front wall 2 is subsequently placed over the non-return valve 30 and the rear sheet 34 such that the non-return valve 30 is sandwiched between the front and rear walls 2,4. The front and rear walls 2,4 are then bonded to each other about their periphery by thermal welding, with the exception of the lower edge 24. The peripheral edges of the non-return valve 30 are located inboard of the peripheral edges of the front and rear walls 2,4. Therefore, no bonding occurs between the non-return valve 30 and the pouch walls 2,4 during this second thermal welding step. The non-return valve 30 is therefore bonded to the pouch 1 by the bonding region 14 only. This ensures that the thermal weld between the front and rear walls 2,4 is optimises, and not comprised by locating edges of the non-return valve between these layers. Bonding the non-return valve 30 to the rear wall 4 by the annular bonding region only allows the non-return valve 30 to

independently flex within the pouch, which assists in preventing blockage, and also optimises sealing of the non-return valve 30 as will be discussed below.

The aperture 42 may slightly inwardly overlap the aperture 18 such that the rear sheet 34 secures directly to both the rear wall 4 and the mounting plate 8, or it may secure directly to the rear wall 4 and indirectly to the mounting flange 8 via the rear wall 4. The rear sheet 34 is therefore sealed around the opening aperture 10. In this way the front 32 and rear 34 sheets of the non-return valve define a chamber 44 at the opening into the pouch 1 that is sealed at its sides 40 and upper end 36, and open at its lower end 38. The nonreturn valve 30 is secured to the pouch 1 by the annular bonding region 14 only and hangs freely within the pouch 1. In particular the lower end 38 is not secured to the adjacent side edges 6 of the pouch 1.

A laminar arrangement is now formed including the rear wall 4, the non- return valve 30 and the front wall 2, with the mounting plate 8 bonded to the rear wall 4. The front and rear walls 2,4 are provided as stock sheets. At this stage the front and rear walls 2,4 are thermally welded, with the thermal weld defining the peripheral shape of the pouch 1. In a further step the pouch 1 is die cut along the line of the thermal weld to form the pouch 1. The die cut preferably intersects the heat weld to ensure that the pouch is sealed at outer peripheral edge.

As waste matter from the stoma enters the pouch 1, it does so within the confines of the chamber 44 of the non-return valve 30. The front 32 and rear 34 walls of the non-return valve, sealed along their side edges 40 and upper edge 36, taper and channel the waste matter downwardly to the opening 46 at the lower end 38. The end 38 of the non- return valve 30 extends approximately half way down the length of the main collection portion 48 of the chamber of the pouch 1. Waste matter, which may be either solid or liquid waste, exits the non-return valve 30 via the opening 46 into the main collection volume of the pouch 1. As the tapered body of the non- return valve 30 is downwardly extending from the opening 10, waste matter passes freely therethrough and out of the opening 46.

In a non-use state the front 32 and rear sheets 34 in the region of the opening will cling to each other, with this surface adhesion holding the opening closed. However, the weight of the waste mater is more than sufficient to overcome this weak clinging force. The size of the opening is narrower than the upper end of the non-return valve 30 but is selected to allow solid matter to freely pass therethrough without clogging.

In the event that the pouch 1 is upturned, or compressed, any waste matter travelling back up through the pouch 1 in the direction of the opening 10 may pass either side of the free end 38 of the non-return valve 30 to the top of the chamber on the outside of the non-return valve 30. As the non-return valve 30 is sealed by the bonding region 14 around the opening 10, any waste matter external to the non-return valve 30 is sealed from the opening and contained within the pouch. Any waste matter that attempts to enter the non- return valve 30 via the opening 38 is prevented from doing so by the surface adhesion or clinging force between the two films of the non- return valve 30 at the outlet opening 38 that holds the outlet 38 closed. In addition, as waste matter engages the freely hanging end 37 this engagement causes the free end 37 to fold back on itself and/or causes the body of the non-return valve 30 to otherwise collapse upwardly on itself, thereby preventing the waste matter from entering the chamber 44. The free end 37 of the non-return valve 30 is able to fold back on itself on contact with the waste matter as it is independently movable relative to the front 2 and rear 4 walls, the non-return valve 30 being bonded only by the bonding region 14. The side edges 40 in particular are spaced from the sealed seam 6 of the pouch 1 and are not secured to the pouch 1 in any way. In this way, waste matter may exit into the main chamber 48 of the pouch 1 via the non-return valve 30, but may not pass back into the non-return valve 30 and is therefore sealed from the opening 10 once inside the main chamber 48 of the pouch.

The pouch 1 further includes a secondary chamber 50 located at the front of the pouch 1, towards the lower end 23. The secondary chamber 50 is a liquid collection chamber arranged to separate liquid waste from solid waste within the pouch 1. The secondary chamber 50 is formed from a third wall 52 located in front of the front wall 2 and having substantially the same shape as the front wall 2. The third wall 52 is sealed to the front wall 2 around its peripheral edge that is aligned with the peripheral edges 6 of the front 2 and rear 4 walls and is simultaneously thermally welded thereto in the same sealing operation. The third wall 52 is thermally welded to the front wall 2 along a first lateral seal 58 that extends from one peripheral side edge 53 of the pouch 1 to the other. The first seal 58 is located below the level of the opening 38 of the non-return valve 30. The third wall 52 is also thermally welded to the front wall 2 along a second lateral seal 60 that also extends from one peripheral side edge 53 of the pouch 1 to the other. The second seal 60 is located below the first seal 58. The secondary chamber 50 is formed between the front sheet 2 and third sheet 52 between the first 58 and second 60 lateral seals.

A liquid outlet pipe 62 is provided having a first end 64 extending into the secondary chamber 50. The outer surface of the first end 64 is sealed between the front sheet 2 and the third sheet 52 by the second lateral seal 60. The outlet pipe 62 is in fluid

communication with the secondary chamber 50 via the opening at the first end 62. A bung 65 is located at the second end of the pipe 62 to close the pipe during normal use and externally seal the chamber 50. A filter section 63 of the front wall 2 is defined between the first seal 58 and second seal 60 is provided with a series of perforations 66. The perforations preferably comprise a series of laterally extending slits 66 having a substantially s-shaped form. The slits 66 are sized to permit the flow of liquid into the secondary chamber 50 from the first storage chamber 48, while preventing the passage of solid matter, thereby acting as a liquid filter.

The s-shape of the slits forms two opposingly oriented semi-circular flaps that assist in allowing the passage of liquid onto the secondary chamber 50. Liquid enters the second chamber 50 through the filter 63 in the direction indicated by arrow A. As the first chamber fills with liquid and solid matter, the liquid filters through the filter section 63 and collected in the secondary chamber 50. This liquid is able to be drained away from the secondary chamber 50 by opening the bung 66 while retaining the solid matter in the storage chamber 48. Liquid may continue to flow into the secondary chamber 50 as it is being drained. The outlet pipe 62 may be connected to a long term drain rather than simply opened periodically for emptying if required.

In an alternative embodiment the non-return valve 30 may be secured to the pouch 1 by at least part of its peripheral edge. As shown in Figure 3 the non-return valve 30 is secured to the pouch 1 by its upper edge 36. The upper edge 30 is located between the peripheral edges of the front wall 2 and rear wall 4. During thermal welding of the peripheral edge of the pouch 1, the upper edge 36 that is sandwiched between the front 2 and rear 4 walls is thermally bonded to the front 2 and rear walls by its outer second surfaces which comprise a thermally weldable material, with the first inner surfaces of the non-return valve 30 being RF welded along the upper edge.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. An ostomy pouch comprising:

first and second walls defining a storage chamber for receiving bodily waste matter;

an opening for receiving bodily waste matter to be stored in the pouch; and a waste channel located within the storage chamber of the pouch, the waste channel being formed from a flexible material and having an inlet sealed around the opening of the pouch and an outlet provided at a free end spaced from the opening, the waste channel being configured to channel bodily waste matter from the opening into the storage chamber through the outlet, the free end of the waste channel being reconfigurable between an open configuration in which bodily waste is able to pass through the outlet into the storage chamber and a closed

configuration in which waste within the storage chamber is prevented from entering the waste channel through the outlet.

2. An ostomy pouch according to claim 1 wherein the free end of the waste channel is movable relative to the first and second walls of the storage chamber such that the free end is able to deform upon contact with solid or liquid matter contained within the storage chamber to close the outlet and prevent said solid or liquid matter contained in the storage chamber from entering the waste channel through the outlet.

3. An ostomy pouch according to claim 1 or 2 wherein free end of the waste channel forms a flap that is movable between an unfolded condition in which matter within the storage chamber is able to pass through the outlet, and a folded condition in which the secondary chamber is sealed preventing matter from within the storage chamber from entering the waste channel.

4. An ostomy pouch according to any preceding claim, wherein the first and second walls of the storage chamber are sealed to each other around their peripheral edges and the waste channel has a peripheral edge that is spaced inwardly of the peripheral edges of the first and second walls.

5. An ostomy pouch according to claim 4 wherein the opening is formed in the first wall of the pouch and the waste channel is sealed around the opening of the pouch by a bonding region that bonds the waste channel to the first wall, and wherein the waste channel is secured to the pouch by the bonding region only.

6. An ostomy pouch according to claim 5 wherein the waste channel is formed by third and fourth flexible films sealed to each other along at least their side edges with at least part of their lower edge being unbonded to define the outlet.

7. An ostomy pouch according to claim 6 wherein the third and fourth films are also sealed along their upper edges.

8. An ostomy pouch according to claim 6 wherein the first and second flexible sheets of the waste channel have adjacent inner surfaces having material properties suitable for radio frequency welding and external surfaces having material properties suitable for thermal welding.

9. An ostomy pouch according to claim 8 wherein the first and second sheets are formed from a laminate material having polythene layer and a polyester later, with the first and second sheets being arranged such that polyester layers are inwardly facing within the interior of the waste channel and the polythene layers are outwardly facing on the exterior surfaces of the waste channel.

10. An ostomy pouch according to claim 7 wherein peripheral edges of the waste

channel are bonded by radio frequency welding and the waste channel is bonded to the first wall of the pouch by thermal welding.

11. An ostomy pouch according to any one of claims 6 to 10 wherein the medical pouch is an ostomy pouch and the opening defines a stoma opening, the pouch further comprising a mounting disc having an aperture formed therein defining the stoma opening, the third film being sealed to the mounting disc around the stoma opening such that bodily waste matter entering the pouch via the opening enters the waste channel and is sealed proximate the opening from the storage chamber.

12. An ostomy pouch according to claim 11 wherein the third film is thermally welded to the mounting disc, the thermal weld forming an annular seal spaced radially outwards from the opening.

13. An ostomy pouch according to claim 11 wherein the first film is thermally welded to the mounting disc along a common seal with the third film, the first film being at least partially located between the third film and the mounting disc.

14. An ostomy pouch according to claim 1 wherein the outlet is located at the free end of the waste channel which in use is arranged below the opening the waste channel tapers inwardly towards the outlet.

15. An ostomy pouch according to any preceding claim wherein the first and second walls comprise first and second flexible waterproof films sealed to each other around their peripheral edges to form said storage chamber.