GB2527278A

GB2527278A - Insertion device for an irrigation system

Info

Publication number: GB2527278A
Application number: GB1408473.5A
Authority: GB
Inventors: Jon Hitchcock; Paul Bird; Mark Newton
Original assignee: Welland Medical Ltd
Current assignee: Welland Medical Ltd
Priority date: 2014-05-13
Filing date: 2014-05-13
Publication date: 2015-12-23
Anticipated expiration: 2034-05-13
Also published as: GB2527278B; GB201408473D0

Abstract

An insertion device 1 for an anal or stoma irrigation system, comprises a positioning member 5 and a hollow shaft 3 having a closed distal end and at least one exit aperture 7, wherein each exit aperture is set in from the outer surface of the insertion device by means of one or more recessed areas arranged around the or each exit aperture. This provides increased user comfort, since the sharp edges of the aperture do not contact the perianal skin. The positioning device 5 may be a hemispherical collar. The recessed areas may be concentric or asymmetric around the aperture and the aperture itself may be round or oval. The device may be single use and/or flushable and made from a biodegradable material. The device may be a flushable catheter or retention balloon catheter.

Description

Insertion Device for an Irrigation System The present invention relates to insertion device, preferably a single use insertion device, for an anal or stoma irrigation system, and the use of such an insertion device in an irrigation system for anal or stoma irrigation.

Background

Anal irrigation is used to prevent constipation and also where a user is incontinent.

This method is used when a user does not have bowel control, for example, when a user has a spinal cord injury. The use of anal irrigation is necessary for both the health and the quality of life of the user. The primary application of the present invention is to assist people with faecal incontinence and/or chronic constipation. Anal irrigation alleviates symptoms of bowel dysfunction by reducing the time spent on the toilet and increases a user's quality of life, thus offering significant advantages to those suffering from neurological disorders or brain tumours; those with spinal cord injury, or suffering from spina bifida; Alzheimer's disease, multiple sclerosis, Parkinson's disease, or apoplexies. Anal irrigation also has applications to users with reduced tissue elasticity, common in elderly people or after multiple births; to users with sensory disorders, which can occur after surgery; and also to users with psychological or psychiatric disorders.

Similarly, stoma irrigation is used to regulate bowel movements by emptying the colon at a scheduled regular time, e.g. once a day or once every second day. The process involves infusing water into the colon through the stoma, thus stimulating the colon to empty. Thus, a stoma irrigation system may be used as an alternative to using ostomy pouches or bags. Stoma irrigation can also be used to help colostomy and ileostomy patients avoid constipation.

Existing anal irrigation devices and methods include those disclosed in patent publications WO 05/032617 and EP 1434611. An anal catheter is inserted into the rectum through the anus and retained by a balloon, which acts as a fixation device.

The balloon is inflated against the bowel wall. A liquid, such as water or a saline solution, is then pumped from a reservoir into the rectum through the anal catheter.

A hand pump is used to pump air into the reservoir to force liquid to flow from the reservoir into the anal catheter and into the user. The balloon fixation device is then removed, which allows the bowel to evacuate with the flow of water triggering perista isis.

The insertion/fixation device used in anal irrigation can be a single-use device, which needs to be disposed of after use. A new fixation device is then used for each anal irrigation treatment. EP1011754 discloses the use of a polyurethane foam fixation member, which is compressible and resilient to retain the device in use, with gauze attached to assist removal from the rectum after use. tJS5578017 discloses a flexible plastic nozzle fixation member, which has self-adhesive securing means for attachment to a user. Single-use fixation devices need to be safely and hygienically disposed of after removal. For example, the device is wrapped up and disposed of in a waste bin.

This can often be inconvenient, messy and embarrassing for a user, especially when the users of such devices have limited manual dexterity. Alternatively, the fixation device can be re-usable. This requires the device to be thoroughly washed and stored hygienically between use, which increases the time and inconvenience involved in the treatment.

WO 2013/076448 discloses an insertion device for an anal irrigation wstem, in which the structure of the device is weakened upon immersion in a toilet bowl to become less buoyant such that the device can be flushed away. The insertion device may be used in conjunction with the anal irrigation system disclosed in wa 2013/076446.

Since the insertion device can be flushed down a toilet in its entirety, it is convenient and hygienic to use, and allows a user to easily and safely carry out their daily routine.

Existing insertion devices, in particular single use insertion devices, generally comprise a cylindrical, hollow shaft having a positioning collar at the base and extending to an aperture at the tip. In use, an insertion device is connected to a reservoir of fluid, e.g. water, by a length of tubing which is inserted substantially along the full length of the hollow shaft of the device and secured in place. The insertion device is inserted into the rectum or stoma and remains in position while a pump is used to pump air into the fluid reservoir, forcing fluid to flow from the reservoir through the tubing and out of the aperture at the tip of the insertion device into the user. Once the insertion device is removed from the rectum or stoma, the bowels evacuate as the presence of water triggers peristalsis.

Exit apertures in existing insertion devices tend to be small, generally cylindrical openings of a constant diameter in the wall of the insertion device. The exit apertures are generally positioned at the distal tip of the insertion device, although where more than one aperture is provided, they may be spaced a small distance from the tip. The cylindrical geometry of the exit apertures means that a sharp edge surrounds each aperture on the external surface of the insertion device. The sharp edges, particularly where the aperture is positioned at the distal tip of the device, can lead to irritation, discomfort, or pain for the user when the outer surface of the device comes into contact with the perianal skin, peristomal skin, or any part of the bowel during insertion and/or removal of the device. Exit apertures of this geometry can also be susceptible to blockage.

Accordingly, there remains a need for an insertion device for use in an anal or stoma irrigation system, which reduces discomfort for the user compared with existing devices.

The present invention sets out to provide an insertion device which alleviates the problems described above by providing an internal fixation device that is shaped to minimise discomfort during use.

Summary of the Invention

In one aspect, the invention provides an insertion device for an anal or stoma irrigation system comprising a positioning member and a hollow shaft having a closed distal end and at least one exit aperture, wherein the or each exit aperture is set in from the outer surface of the insertion device by means of one or more recessed areas arranged around the or each exit aperture.

The following definitions shall apply throughout the specification and the appended claims.

Within the context of the present specification, the term "comprises" is taken to mean "includes" or "contains", i.e. other integers or features may be present, whereas the term "consists or' is taken to mean "consists exclusively of".

Within the context of the present specification, the term "about" is interpreted to mean optionally ±20%, preferably optionally lO°/o, more preferably optionally ±S%.

Unlike the arrangement used in earlier insertion devices, the exit apertures of the device are set in from the outer surface of the insertion device. By setting the exit apertures in from the outer surface of the insertion device and providing recessed areas arranged around the exit apertures, the relatively sharp edges around the apertures are medially translated and a smoother edge is formed. This reduces pressure and assists in the smooth insertion of the device.

Preferably, the recessed areas are concentrically or asymmetrically arranged around the or each exit aperture.

Preferably, the or each exit aperture is set in from the outer surface of the insertion device by at least about 1 mm. Preferably, the or each exit aperture is set in from the outer surface of the insertion device by up to about 5 mm.

Preferably, the or each exit aperture is round, oval or elliptical.

Preferably, the or each exit aperture is offset from the distal tip of the insertion device.

This positioning of the exit apertures assists in minimising discomfort to the user.

The centre of the or each exit aperture is preferably offset by at least about 5 mm from the distal tip of the insertion device. For example, the centre of the or each exit aperture may be offset by at least about 5 mm, at least about 6 mm, or at least about 7 mm from the distal tip of the insertion device. The centre of the or each exit aperture is preferably offset by up to about 20 mm from the distal tip of the insertion device.

For example, the centre of the or each exit aperture may be offset by up to about 10 mm, up to about 15 mm, or up to about 20 mm from the distal tip of the insertion device.

Preferably, there are two or more exit apertures. For example, there may be two, three, four, five, six, seven, or eight exit apertures. Multiple exit apertures ensure that water can still pass through and exit the insertion device, in the event that one of the apertures was to be blocked. Preferably, there are two, three or four exit apertures.

More preferably, there are two or three exit apertures. In one particularly preferred embodiment of the present invention, there are two exit apertures.

In one embodiment of the invention, the insertion device is a single use insertion device. For example, the insertion device may take the form of a flushable catheter.

In another embodiment of the invention, the insertion device may take the form of a retention balloon catheter.

Preferably, the insertion device of the present invention is flushable, i.e. it has a structure that is weakened upon immersion in a toilet bowl to become less buoyant such that the device can be flushed away. In one embodiment of the present invention, the internal fixation device is suitable to be flushed down a toilet in its entirety. A flushable insertion device allows for convenient and hygienic disposal after anal irrigation. Advantageously, a user is not required to wash or wrap the device for re-use or disposal and the device can be easily disposed of by users with limited manual dexterity.

In one preferred embodiment, the insertion device comprises a water soluble material.

In this embodiment, the insertion device preferably comprises a polyvinyl alcohol material.

It has been found that polyvinyl alcohol of the required grade ensures that the insertion device remains insoluble and stable when stored and when it is inserted into the rectum, whilst the device is water softenable and biodegradable over a longer period of time.

In another preferred embodiment, the insertion device comprises a biodegradable material.

In an alternative embodiment of the invention, the insertion device comprises polyvinyl chloride (PVC).

S In another alternative embodiment of the invention, the insertion device comprises a thermoplastic elastomers (TPE) material. Preferred TPE materials include styrenic block copolymers (TPE-s), polyolefin blends (TPE-o), elastomeric alloys (TPE-v or TPV), thermoplastic polyu rethanes (TRU), thermoplastic copolyester, and thermoplastic polyamides. Optionally, the TPE material may comprise one or more additives. The TPE material may advantageously be provided with a hydrophilic coating.

In another preferred embodiment of the invention, the insertion device comprises a hydrophilic coating. In an alternative preferred embodiment of the invention, the insertion device comprises one or more hydrophilic additives.

Preferably, the insertion device is self-lubricating when wet.

Advantageously, an insertion device that is self-lubricating allows for easier insertion of the device into the rectum and prevents unintended expulsion of the device. The process of lubrication is an integral part of priming the water conduit and once "wetted" the device is insertable into the anus without requiring any additional lubrication.

The insertion device may have any length that is appropriate for its particular use. For example, the insertion device may have a length from about 50mm to about 150mm.

In one preferred embodiment, the insertion device has a length of about 70mm.

In another preferred embodiment, the insertion device has a length of about 110mm.

Preferably, the hollow shaft has a length of between about 50mm and about 90mm.

More preferably, the hollow shaft has a length of about 51mm.

Preferably, the hollow shaft has an outer diameter of between about 7.5mm and about 20mm. More preferably, the hollow shaft has an outer diameter of between about 8mm and about 15mm. Most preferably, the hollow shaft has an outer diameter of between about 10mm and about 12.5mm.

Preferably, the hollow shaft has an inner diameter of between about 4.5mm and about 9.5mm. More preferably, the hollow shaft has an inner diameter of between about 6mm and about 8mm. Most preferably, the hollow shaft has an inner diameter of about 7mm. In one preferred embodiment, the inner diameter of the hollow shaft is such that tubing with an outer diameter of about 6.35mm may be placed within the shaft.

In one preferred embodiment of the invention, the wall thickness of the hollow shaft varies along its length.

In this embodiment, preferably, the wall thickness of the hollow shaft is greater adjacent to the or each exit aperture than adjacent to the positioning member.

In this embodiment, preferably, the wall thickness of the hollow shaft is between about 0.5mm and about 5.0mm adjacent to the positioning member and between about 0.7mm and about 5.7mm adjacent to the or each exit aperture. More preferably, the wall thickness of the hollow shaft is about 1.5mm adjacent to the positioning member and about 3.2mm adjacent to the or each exit aperture.

Preferably, the outer wall of the hollow shaft is tapered from the or each exit aperture towards the positioning member at an angle of between about 0.5 and about 5.5 degrees from the vertical axis of the hollow shaft.

More preferably, the outer wall of the hollow shaft is tapered at an angle of about 3.0 degrees from the vertical axis of the hollow shaft.

A thicker wall around the exit aperture of the hollow shaft ensures that the area of the shaft that is in contact with water for the greatest amount of time is stable and will remain secure and intact during the period of use of the device.

Preferably, the internal wall of the hollow shaft is tapered from the positioning member towards the or each exit aperture at an angle of between about 0.5 and about 4.0 degrees from the vertical axis of the hollow shaft.

More preferably, the internal wall of the hollow shaft is tapered from the positioning member towards the or each exit aperture at an angle of about 1.5 degrees towards the vertical axis of the hollow shaft.

The insertion device is preferably manufactured by injection moulding and the tapering of the internal wall of the insertion device allows for easier removal of the insertion device from the mould.

Preferably, the positioning member comprises a substantially hemispherical collar.

A hemispherical collar allows a user to safely and conveniently hold the device for insertion and use and also assists with the correct positioning of the device by preventing over-insertion and the potential for internal damage of a user.

Preferably, the positioning member has a substantially elliptical or oval base.

Optionally, the positioning member has a substantially circular base.

Preferably, the internal surface of the positioning member comprises one or more channels.

Optionally, the internal surface of the positioning member comprises one or more protrusions.

More preferably, the internal surface of the positioning member comprises two or more channels.

Channels or protrusion(s) on the internal surface of the positioning member increase the surface area of the insertion device, which comes into contact with water when the device is immersed in a toilet bowl. This has the advantage of increasing the speed at which the device breaks down and can be flushed away.

Preferably, each channel is equally spaced around the inner surface of the positioning member.

More preferably, the channels are spaced apart from each other by a distance of at least about 10mm.

Optionally, the or each channel is straight.

Optionally, the or each protrusion is straight or curved.

Straight channels or protrusions allow for ease of manufacture. Curved channels or protrusions provide the advantage that they strengthen the device whilst it is stored and when it is in use.

Preferably, the hollow shaft of the insertion device comprises at least one annular recess around its inner surface.

Optionally, the hollow shaft of the insertion device comprises at least one annular protrusion around its inner surface.

An annular recess or protrusion on the inner surface of the hollow shaft provides the advantage of a secure "click-fit" with a corresponding protrusion or recess around the tip of a water conduit, which is inserted into the insertion device for use in anal irrigation. This ensures that that the water conduit is correctly fitted and provides the advantage of giving reassurance to the user that the insertion device is safe and ready to use.

Detailed Description

For the purposes of clarity and a concise description, features are described herein as part of the same or separate embodiments; however it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described.

The invention will now be described by way of example with reference to the accompanying diagrammatic drawings, in which:-Figure 1 is a front view of an insertion device constructed in accordance with an embodiment of the present invention; Figure 2a is a sectional view of the insertion device of Figure 1 through line A-A; Figure 2b is an enlarged view of detail C shown on Figure 2a; Figure 3 is a perspective schematic view of the insertion device of Figure 1 showing the external features of the device; Figure 4a is a side view of the insertion device of Figure 1; Figure 4b is a sectional view of part of the insertion device through line D-D as shown on Figure 4a; Figure 5 is a view from below of the insertion device of Figure 1; and Figure 6a is a top view of an insertion device constructed in accordance with another embodiment of the present invention; Figure 6b is a sectional view of the insertion device of Figure 6a through line A-A; Figure 7a is a side view of the insertion device of Figure 6a; Figure 7b is a sectional view of part of the insertion device of through line B-B as shown on Figure 7a.

Referring to Figure 1, one embodiment of the insertion device 1 of the present invention is an approximately frustoconical device comprising a substantially tubular insertion shaft 3 integrally formed with a positioning collar 5. The device 1 may be injection moulded. The device may be formed from a water soluble material, such as a polyvinyl alcohol material (PVOH). The grade of PVOH used ensures that the device 1 remains insoluble when it is stored in sealed packaging and when it is inserted during use. However, over a longer period of time, the material is water-softenable and biodegradable. The material used is self-lubricating when wet and slightly adhesive or "tacky" when drying. In use, this assists in insertion of the device and reduces any unintended expulsion of the device.

As shown in Figures 1, 3 and 4a, an embodiment of the insertion device 1 of the present invention is a catheter, shaped to interact with the anal sphincter to encourage retention of the device 1. The device 1 comprises a substantially cylindrical, hollow shaft 3 extending from a positioning collar 5 at its base to a rounded tip having one on two apertures 7 slightly offset from the distal tip. The positioning collar 5 forms a funnel-shape with the hollow shaft 3. In alternative embodiments, the hollow shaft has multiple apertures near its tip and/or spaced around its surface. In the event that one or more apertures were to be blocked, additional apertures would ensure that water could still escape from the insertion device to allow irrigation. The positioning collarS assists with insertion into the anal sphincter and prevents over-insertion of the device 1.

The length of the device 1 is between 50 and 150mm. In a preferred embodiment the overall length of the device 1 is 70mm and the length of the hollow shaft 3 is 51mm.

Referring to Figures 2a and 4a, the hollow shaft has an outer diameter (Dl, D2) of between 10 and 12.5mm and an inner diameter (D3) of 7mm. The inner diameter (D3) is sized according to the water conduit that is to be inserted into the shaft 3 in use.

The wall thickness of the shaft 3 varies along its length between 1.5mm adjacent to the positioning collar S to 3.2mm at the tip, adjacent to the apertures 7 and furthest from the positioning collarS. The thicker end of the shaft 3 is furthest from the collar S and, in use, is in contact with water for a greater amount of time. The increased wall thickness ensures that the device 1 is stable enough to remain secure and intact during use.

The thickness of the shaft wall is configured to ensure a sufficient thickness for the device to be stable during use whilst minimising the amount of material from which the device is made to ensure that the device will dissolve after use.

As shown in Figure 2a, the internal wall of the hollow shaft 3 is tapered at an angle of 1.5 degrees towards the vertical axis from the positioning collar S towards the distil tip and apertures 7 of the device 1. The tapering of the internal wall allows for ease of removal of the insertion device 1 from the mould into which it is injected and formed.

The tapering of the internal hollow of the shaft 3 also allows for uniform pressure to be applied to the water conduit inserted into the device during use. The outer wall of the shaft 3 is tapered at an angle of 3.0 degrees to the vertical axis from the distil tip and apertures 7 of the device 1 towards the positioning collar 5.

The positioning collar 5 may have a circular base with a diameter of between about 20 and about 70 mm (not shown). In a preferred embodiment of the invention, shown in Figure 1 and Figure 3, the positioning collar S has an elliptical or oval cross section with a major diameter of about 47 mm and a minor diameter of about 35 mm. The positioning collar is curved and it slopes at an angle of between about 0.5 degrees and about S degrees to the longitudinal, vertical axis of the shaft 3 of the device 1. The angle of the slope, ensures that the device 1 can easily be inserted and removed.

As shown in Figures 5a and Sb, the internal surface of the positioning collar S comprises a series of ridges or cut-outs 9 extending along the internal surface of the positioning collar 5 between its base and the hollow shaft 3. Figure Sa shows a positioning collar with an elliptical base and straight ridges 9 between the base of the shaft 3 and the base of the positioning collarS. In alternative embodiments of the device (not shown), the ridges 9 may be curved which may strengthen the device during storage and/or use, and/or protrusions may extend along the internal surface of the positioning collar.

In the preferred embodiment shown in Figure Sa, a series of ridges/channels 9 are equally spaced around the inner surface of the positioning collar 5 with a distance of at least 10mm between each ridge at the base of the insertion device 1. On immersion in water, these external ridges 9 increase the surface area of the device 1 that comes into contact with water. The ridges 9 fold inwardly towards each other on immersion and decrease the time taken for the device 1 to dissolve. They also assist in the flushing of the device 1 because they allow the catheter to break down into easily flushable strips.

In use, the insertion device 1 is sufficiently rigid to allow a user to insert the device securely and comfortably into the rectum. The insertion device 1 may be connected to a reservoir of fluid, such as water, by a length of tubing, referred to as a water conduit, which is then inserted into the hollow shaft of the insertion device 1 and held securely in place. The water conduit is inserted substantially along the full length of the hollow shaft, which assists in maintaining stability of the device 1 once inserted.

In one embodiment, the insertion device 1 and the water conduit have a "click-fit", wherein an annular protrusion around the tip of the water conduit mates with a corresponding annular recess around the hollow shaft 3 of the insertion device 1 (as shown in Figure 2b). The water conduit is inserted until the protrusion mates with the recess and a "click" sound indicates that the conduit is held in place. It is also envisaged that a "click-fit" between the water conduit and the insertion device could be achieved wherein an annular recess around the tip of the water conduit mates with a corresponding annular protrusion inside the hollow shaft of the insertion device. In an alternative embodiment, a lever is used to assist in sliding the water conduit into the insertion device without the user contacting the water conduit. When the water conduit is sufficiently inserted into the hollow shaft of the insertion device, the lever is removed.

In use, a water reservoir is connected to a pump and the insertion device 1 acts as an irrigation nozzle, which is inserted into the rectum or stoma and will remain in position whilst the pump is used to pump air into the reservoir. The pump may be operated by a lever switch or pedal and forces water to flow from a reservoir through a water conduit, through the anal insertion device land out of the or each aperture 7 therein, into the user. The insertion device 1 is then removed from the rectum or stoma, allowing the bowels to evacuate as the presence of water triggers peristalsis.

After use, the insertion device 1 may be disposed of. Where the insertion device is made of fiushable materials, it can be placed into a toilet bowl and will become weakened on immersion in water to gradually dissolve so that the device can be flushed away.

As shown in Figures 6a, 6b and 7a, another embodiment of the insertion device 11 of the present invention is a retention balloon catheter comprising a substantially tubular hollow shaft 13 integrally formed with a positioning collar 15. The device 11 may be injection moulded and/or may be formed from polyvinyl chloride (PVC). The hollow shaft 13 may be provided with a hydrophilic coating. The catheter is shaped to interact with the anal sphincter and the catheter further comprises a gas conduit 18 attached to a balloon to facilitate retention of the device 11. The hollow shaft 13 comprises a recessed annular section 19 within which the balloon is positioned to ensure ease and comfort of insertion. The device 11 comprises a substantially cylindrical, hollow shaft 13 extending from a positioning collar 15 at its base to a rounded tip having two apertures 17 offset from the distal tip. The positioning collar 15 forms a funnel-shape with the hollow shaft 13. The positioning collar 15 assists with insertion into the anal sphincter and prevents over-insertion of the device 11. A stepped adaptor 20 is also provided at the base of the hollow shaft 13 to facilitate connection with a conduit to allow a liquid, such as water, to be introduced into the device.

The length of the device 11 is between 50 and 150mm. In the preferred embodiment shown, the overall length of the device 11 is 110mm and the length of the hollow shaft 13 is 102 mm. Referring to Figure 6b, the hollow shaft has an outer diameter of between 9.5 and 12mm.

The positioning collar 15 may have a circular base with a diameter of between about 20 and about 70 mm (not shown). In a preferred embodiment of the invention, shown in Figure 8, the positioning collar 15 has an elliptical or oval cross section with a major diameter of about 49 mm and a minor diameter of about 34 mm. The positioning collar is curved and it slopes at an angle to the longitudinal, vertical axis of the shaft 13 of the device 11. The angle of the slope, ensures that the device 11 can easily be inserted and removed.

In use, the insertion device 11 is inserted into the rectum, and the balloon is inflated with air or another suitable gas provided via gas conduit 18. The balloon has a capacity of approximately four times the required air volume. The inflated balloon acts to secure the catheter in the required position. A liquid conduit is connected to adaptor allowing water to flow through the insertion device 11 and out of the or each aperture 17 therein, into the user. When the process of irrigation is complete, the balloon is deflated, and the insertion device 11 is removed and disposed of. Removal of the insertion device 11 allows the bowels to evacuate as the presence of water triggers perista isis.

The above described embodiments have been given by way of example only, and the skilled reader will naturally appreciate that many variations could be made thereto without departing from the scope of the claims.

Claims

Claims 1. An insertion device for an anal or stoma irrigation system comprising a positioning member and a hollow shaft having a closed distal end and at least one exit aperture, wherein the or each exit aperture is set in from the outer surface of the insertion device by means of one or more recessed areas arranged around the or each exit aperture.
2. The insertion device of claim 1 wherein the recessed areas are concentrically or asymmetrically arranged around the or each exit aperture.
3. The insertion device of claim 1 or claim 2 wherein the or each exit aperture is set in from the outer surface of the insertion device by at least about 1 mm.
4. The insertion device of any of claims 1 to 3 wherein the or each exit aperture is set in from the outer surface of the insertion device by up to about 5 mm.
5. The insertion device of any of claims 1 to 4 wherein the or each exit aperture is round, oval or elliptical.
6. The insertion device of any of claims 1 to 5 wherein the or each exit aperture is offset from the distal tip of the insertion device.
7. The insertion device of any of claims 1 to 6, wherein the centre of the or each exit aperture is offset by at least about 5 mm, at least about 6 mm, or at least about 7 mm from the distal tip of the insertion device.
8. The insertion device of any of claims 1 to 7, wherein the centre of the or each exit aperture is offset by up to about 10 mm, up to about 15 mm, or up to about 20 mm from the distal tip of the insertion device.
9. The insertion device of any of claims 1 to 8, wherein there are two or more exit apertures, optionally wherein there are three, four, five, six, seven, or eight exit apertures.
10. The insertion device of any of claims ito 9, wherein the insertion device is a single use insertion device.
ii. The insertion device of claim 10, wherein the insertion device takes the form of a flushable catheter or a retention balloon catheter.
12. The insertion device of any of claims ito 11, wherein the insertion device is flushable
13. The insertion device of any of claims i to i2, wherein the insertion device comprises a water soluble material, optionally wherein the insertion device comprises a polyvinyl alcohol material.
14. The insertion device of any of claims ito i3, wherein the insertion device comprises a biodegradable material.
15. The insertion device of any of claims i to i4, wherein the insertion device comprises polyvinyl chloride.
16. The insertion device of any of claims ito iS, wherein the insertion device is self-lubricating when wet.
17. The insertion device of any of claims 1 to i6, wherein the insertion device has a length from about 50mm to about 150mm.
18. The insertion device of any of claims ito i6, wherein the hollow shaft has a length of between about 50mm and about 90mm.
19. The insertion device of any of claims ito i8, wherein the hollow shaft has an outer diameter of between about 7.5mm and about 20mm.
20. The insertion device of any of claims ito 19, wherein the hollow shaft has an inner diameter of between about 4.5mm and about 9.5mm.
21. The insertion device of any of claims 1 to 20, wherein the wall thickness of the hollow shaft varies along its length, optionally wherein the wall thickness of the hollow shaft is greater adjacent to the or each exit aperture than adjacent to the positioning member.
22. The insertion device of any of claims 1 to 21, wherein the positioning member comprises a substantially hemispherical collar.
23. The insertion device of any of claims 1 to 22, wherein the positioning member has a substantially elliptical or oval base, optionally wherein the positioning member has a substantially circular base.
24. The insertion device of any of claims ito 23, wherein the internal surface of the positioning member comprises one or more channels and/or one or more protrusions.
25. The insertion device of claim 24 wherein each channel is equally spaced around the inner surface of the positioning member, optionally wherein the channels are spaced apart from each other by a distance of at least about 10mm.
26. The insertion device of any of claims ito 25, wherein the hollow shaft of the insertion device comprises at least one annular recess around its inner surface and/or at least one annular protrusion around its inner surface.
27. An insertion device substantially as herein described with reference to the accompanying drawings.