WO2024124281A1

WO2024124281A1 - A stoma seal

Info

Publication number: WO2024124281A1
Application number: PCT/AU2023/051245
Authority: WO
Inventors: Mervyn DOIG
Original assignee: Doig Mervyn
Priority date: 2022-12-16
Filing date: 2023-12-04
Publication date: 2024-06-20

Abstract

A bidirectional tubular stoma seal (22) for sealing between the skin (60) of an ostomate surrounding an artificial stoma and a tubular fitting (21) of a colostomy irrigation device (20) is disclosed. The seal takes the form of a tube (22), its distal end being formed into a circular slot (40) which opens away from its proximal end and is bounded by a pair of circular opposed walls (41, 42) which form a first sealing frictional fit with one circular end of the tubular fitting (21), The seal proximal end is formed into an annular rim (54) having a tapering substantially triangular cross-section which terminates in a thin apex (55) which forms a flexible circular blade (56) capable of sealing against the skin, The bidirectional seal is moulded from a polyurethane material having a Shore hardness of between 70 and 110. A method of intestinal irrigation is also disclosed.

Description

A Stoma Seal

Field of the Invention

The present invention relates to the sealing of an artificial stoma created in patients (ostomates) which have undergone a colostomy operation.

Background Art

Such ostomates have an artificial stoma, normally located in their abdomen somewhere between their navel and their genitals. Hitherto such ostomates have been obliged to wear a colostomy bag which is sealed to the skin surrounding the stoma by means of a releasable adhesive. However, such bags need to be regularly emptied and the adhesive often irritates the skin around the stoma. Consequently, for most patients the bag needs to be emptied daily and is required to be changed every few days.

International Patent Application No WO 01/00260 (PCT/AU2000/00725) discloses a colostomy irrigation device 10 which uses a pump 40 and irrigating tube 16 to irrigate the end of the intestine adjacent the stoma. In this way, the intestine is able to be emptied of faecal matter which is disposed of into a toilet pan upon which either the patient is sitting, or in front of which the patient is standing. This device has never entered commercial production, let alone had any commercial success. One of the difficulties of the device 10 was the need to provide an adequate seal between the irrigation device 10 and the skin of the patient surrounding the stoma. Unless such an adequate seal is provided, leakage of faecal material inevitably takes place.

Genesis of the Invention

The Genesis of the present invention is a desire to provide such a seal.

Summary of the Invention

In accordance with a first aspect of the present invention there is disclosed a bidirectional tubular stoma seal for sealing between the skin of an ostomate surrounding an artificial stoma and a tubular fitting of a colostomy irrigation device, said seal comprising a tube having a proximal end and a distal end, said distal end being formed into a circular slot which opens away from said proximal end and is bounded by a pair of circular opposed walls, said walls forming a first sealing frictional fit with one circular end of said tubular fitting, said proximal end being formed into an annular rim having a tapering substantially triangular cross-section which terminates in a thin apex which forms a flexible circular blade capable of sealing against said skin, and said bidirectional seal being moulded from a plastics material having a Shore hardness of between 70 and 110.

Preferably, the bidirectional seal is vacuum cast in a silicone mould from polyurethane having a Shore hardness of approximately 90.

More preferably the polyurethane comprises three components, namely a first polyol, an isocyanate, and a second polyol which are mixed in the ratio within the range of from 100: 100: 10 to 100: 100: 90.

Brief Description of the Drawings

A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 reproduces Fig. 12 from the above-mentioned International Patent Application,

Fig. 2 is an exploded perspective view of the apparatus of the preferred embodiment,

Fig. 3 is a partial cross-sectional and perspective view showing the nature of the first seal, and

Fig. 4 is a side elevation, partially in section, showing the nature of the second seal.

Detailed Description

As seen in Fig. 1, the tubular main chamber 11 of an irrigation device 10 is held against the skin of the patient and connected with a pump 40 which both supplies water under pressure and also provide suction to remove the water and faecal matter which is delivered into the conical irrigation device 11. Accordingly, the pump 40 is a complex device. No particular seal is provided between the skin of the patient and the main chamber 11 since reliance is placed upon the suction provided by the pump 40 to prevent any leakage between the conical irrigation device 11 and the patient’s skin. This reliance has proved to be misplaced and the experience of experimental prototypes of the irrigation device 10 is that they did leak in practice.

Turning now to Figs. 2-4, the irrigation device 20 of the preferred embodiment is illustrated having a tubular main chamber 21, a bidirectional seal 22, and a mounting ring 23. The mounting ring enables an elasticised belt, conventional but not illustrated, to be connected between the two slots 33 of the mounting ring 23. The mounting ring 23 is glued to the main chamber 21 and is omitted in Fig. 4 so as to not overburden the drawing.

The main chamber 21 is provided with a first hole 24 which receives a grommet 25. An irrigating tube 26 is slidingly and sealingly received within the grommet 25. A second hole 32 is located in the main body of the main chamber 21 and can, if desired, receive an air tube 35 as illustrated in Fig. 4. In addition, the main chamber 21 is provided with an exit spigot 36 which is provided with an exit tube 37 as illustrated in Fig. 4. The main chamber 21 is preferably formed by vacuum forming using clear acrylic plastic. Thus, the main chamber 21 is substantially rigid.

As illustrated in Fig. 3, the end of the main chamber 21 which mates with the bidirectional seal 22 is provided with a cylindrical wall 40. The adjacent portion of the bidirectional seal 22 is formed into a pair of opposed cylindrical walls 41, 42 which are sized to receive the cylindrical wall 40 with a frictional fit. This creates a first seal between the main chamber 21 and the bidirectional seal 22.

The main body of the bidirectional seal 22 takes the form of a frusto-conical wall 50 which extends between the cylindrical walls 41, 42 and an internal flange 52. Extending radially outwardly from the internal flange 52 is an annular rim 54 having a tapering substantially triangular cross-section which terminates in a thin apex 55 which forms a flexible circular blade 56.

In operation, as illustrated in Fig. 4, the bidirectional seal 22 is held against the skin 60 of the torso of a patient having a stoma located above the level of the patient’s boxer shorts 61. This causes the blade 56 to both dig into the skin 60 slightly and also deflect so as to exert a sealing pressure against the skin 60. This creates the second seal. The first seal is created by the frictional fit between the cylindrical wall 40 of the main chamber 21 and the cylindrical walls 41, 42 of the bidirectional seal 22. The irrigation device 20 is held in the condition illustrated in Fig. 4 by means of the belt (not illustrated).

The irrigating tube 26 is connected to a supply of room temperature water by means of a flexible water tube 45 which is in turn connected to a pouch (not illustrated but similar to a saline bag used in connection with catheters) which is able to be elevated by the patient so as to provide a source of water with an adjustable head of water pressure. The irrigating tube 26 is slid through the grommet 25 so that the leading end of the irrigating tube enters the stoma and thus the intestine of the patient. Raising the water pouch then introduces water into the intestine via the irrigating tube 26.

At the same time, suction is provided by means of a peristaltic pump (not illustrated but conventional) which provides suction via the exit tube 37 and the exit spigot 36 into the interior of the main chamber 21. The degree or intensity of this suction is able to be varied by the patient by means of partially or fully opening or closing the second hole 32 with one of the patient’s fingers. If the air tube 35, as illustrated in Fig. 4 is provided, then the patient’s finger is utilised at the free end of the air tube 35.

In this way, the irrigating water which is introduced into the patient’s intestine, breaks up any stools which may be present or forming in the intestine and forms a slurry which passes alongside the exterior of the irrigating tube 26 and out of the stoma. The slurry therefore passes into the main chamber 21 and exits therefrom via the exit spigot 36 and exit tube 37. This material then passes through the pump (not illustrated) and into a lavatory pan.

Prior to, and after, this irrigating activity, the stoma is closed by means of a rubber stopper of a size similar to that used to stop the neck of a bottle, for example. In this way, the patient is entirely relieved of the need for any colostomy bag or any adhesive which may irritate the skin 60. It is apparent that the bidirectional seal 22 has to simultaneously comply with two conflicting requirements. The first of these is that the cylindrical walls 41, 42 of the bidirectional seal 22 have to be sufficiently rigid to be able to form the desired frictional fit with the cylindrical wall 40. The second is that the blade 56 of the bidirectional seal has to be sufficiently flexible to deflect when it comes into contact with the skin 60, but yet be sufficiently rigid to depress the skin 60 and thereby create an effective seal between the skin 60 and the bidirectional seal 22.

After considerable experiment, the present inventor has discovered that these conflicting requirements of the bidirectional seal 22 are best met by means of a polyurethane elastomer which is able to be vacuum cast and which consists of three components, namely a first polyol, an isocyanate, and a second polyol which are mixed in the ratio 100 : 100 : 10-90 which results in a Shore hardness between approximately 70 and approximately 90. The constituents are available from Axson Technologies having offices in France, Germany, Italy, Spain, the UK, South Korea, Mexico, Japan, USA and China.

The foregoing describes only one embodiment of the present invention and modifications, obvious to those skilled in the biomedical arts, can be made thereto without departing from the scope of the present invention. For example, the features and advantages disclosed in one facet of the invention may be utilised, mutatis mutandis, in other facets of the invention.

The term “comprising” (and its grammatical variations) as used herein is used in the inclusive sense of “including” or “having” and not in the exclusive sense of “consisting only of’.

Claims

1. A bidirectional tubular stoma seal for sealing between the skin of an ostomate surrounding an artificial stoma and a tubular fitting of a colostomy irrigation device, said seal comprising a tube having a proximal end and a distal end, said distal end being formed into a circular slot which opens away from said proximal end and is bounded by a pair of circular opposed walls, said walls forming a first sealing frictional fit with one circular end of said tubular fitting, said proximal end being formed into an annular rim having a tapering substantially triangular cross-section which terminates in a thin apex which forms a flexible circular blade capable of sealing against said skin, and said bidirectional seal being moulded from a plastics material having a Shore hardness of between 70 and 110.

2. The bidirectional seal as claimed in claim 1 wherein the bidirectional seal is vacuum cast in a silicone mould from polyurethane having a Shore hardness of approximately 90.

3. The bidirectional seal as claimed in claim 2 and comprising three components, namely a first polyol, an isocyanate, and a second polyol which are mixed in the ratio 100 : 100 : 10-90