Patent ID: 12186228

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to the drawings, the same reference numerals are used to depict the same or similar features. The features of the following embodiments may be combined as desired; the separate description of features as different embodiments is mainly to ease clarity, and does not in any way mean that certain features should not or cannot be used together.

Referring toFIG.1, a recessed stoma10is illustrated, in which the stoma10is joined to the peristomal skin12at a point14that is slightly below the abdominal skin level16. A most basic form of stoma adapter20comprises, or is in the form of, a tube having a proximal end22inserted into the stoma10and into the funnel shaped mouth defined by the peristomal skin around the recessed stoma10, at least to the level of the stoma10. The stoma adapter20has a distal end24that projects beyond the abdominal skin level16. The distal end24may optionally be angled to direct stomal discharge downwardly, if desired. The distal end24projects at least partly into the entrance aperture26of an ostomy appliance28comprising a collection pouch30. The ostomy appliance28is secured to the peristomal skin12by means of an adhesive body fitment32comprising or consisting of an adhesive wafer. The ostomy appliance28may be a one-piece appliance in which the body fitment32is permanently attached to the pouch30, or it may be a two-piece appliance in which the pouch30may be releasably attached to the body fitment32by means of a releasable coupling (not shown) such as an adhesive coupling or a mechanical interference coupling.

The stoma adapter20defines a free-flow, substantially unobstructed, passage34, to deliver stomal discharge from the proximal end22inserted at the stoma10, to the distal end24projecting into the entrance aperture26of the ostomy appliance28. The stoma adapter20thus closely approximates the function of a stoma with an “ideal” protrusion from the peristomal skin. The stoma adapter22functions as a stoma extender and/or a stoma effluent diverter and/or a stoma liner. The stoma adapter20diverts stomal discharge away from the peristomal skin12, directly into the interior of the ostomy appliance28. By keeping the stomal discharge clear of the peristomal skin12: (i) the risk of the effluent attacking the adhesion between the body fitment32and the peristomal skin12is reduced, thereby leading to better product life; and/or (ii) the risk of irritation or excoriation of the peristomal skin12is very much reduced.

The stoma adapter20may be relatively short, such that the proximal end22does not extend very far into the stoma10(or even is inserted merely to the point14at which the stoma10meets the peristomal skin12). Alternatively, the stoma adapter20may be relatively long such that it extends more substantially into the stoma10. The stoma adapter20preferably defines a discharge passage34that has a longitudinal (axial) dimension that is greater than a minimum transverse dimension (or more preferably greater than a maximum transverse dimension).

The stoma adapter20may be permanently open, to define the free-flow discharge passage34. Alternatively, the stoma adapter20may comprise a valve (depicted generally by the numeral36). The valve36may be disposed at any desired location, for example, at the proximal end22or the distal end24, or intermediate the two. The valve36may be configured as a closed end of the tube. The valve36is configured not to obstruct the discharge of effluent, and is configured to open under the pressure of effluent when the bowel forces the expulsion of effluent. The valve36may be a one-way valve.

In the embodiment ofFIG.1, the stoma adapter20is generally independent of the ostomy appliance28and the body fitment32.

FIGS.2aand2B illustrate a second embodiment in which the distal end24of the stoma adapter20comprises a shoulder or flange38. The flange38acts as a stop to limit the degree of insertion of the stoma adapter20into the stoma10. In the present embodiment, the flange38additionally is dimensioned to engage the body fitment32. For example, the flange38is slightly larger in diameter than the entrance aperture26in the adhesive body fitment32. The flange38is configured to engage the rear surface (inFIG.2B) or alternatively the front surface (not shown) of the body fitment38. For a one-piece appliance, the stoma adapter20can be inserted at the stoma10before the body fitment32of the ostomy appliance28is attached to the peristomal skin12, such that the periphery of the flange38is trapped between the skin12and the body fitment32to hold the stoma adapter20positively in position.

FIGS.3A and3Bshows a modified third embodiment similar to the second embodiment, except for the following refinements:

The flange38is implemented with a rounded funnel shape that joins the tubular portion of the stoma adapter20to define a smoothly rounded tapering profile.

The flange38is releasably or permanently attached to the body fitment32, at a point of attachment indicated generally by numeral40. The point of attachment40may on the distal (front) surface of the adhesive. Such a configuration provides direct transport of effluent from the bowel into the pouch, bypassing peristomal skin12between the stoma10and the inner edge of the adhesive wafer of the body fitment32. It also bypasses the interface between the peristomal skin12and the body fitment32. Attachment between the stoma adapter20and the body fitment32may be accomplished by a variety of means, including adhesive bonding, solvent bonding, and welding (e.g., heat welding, ultrasonic welding, laser welding, or radio frequency welding). The attachment point40may also be adhesive attachment using the adhesion of the skin adhesive in the body fitment32. In the case of any of the adhesive types of attachment, the attachment may be permanent or releasable (e.g., peelable) as desired.

FIGS.4A and4Bshow a modified fourth embodiment similar to the second and third embodiments, except the fourth embodiment uses a mechanical fastener42to join the distal end24of the stoma adapter20to the body fitment32. The mechanical fastener42comprises mating rings44and46on the body fitment32and the stoma adapter20. For example, the ring46of the stoma adapter20may form a snap fit behind the ring44on the body fitment32, to be trapped between the body fitment32and the peristomal skin12. The mechanical fastener42may be releasable while the body fitment32remains in place on the peristomal skin12, or the fastener42may be configured as non-releasable (e.g., at least until the body fitment32is removed). The mechanical fastener42may be augmented by an adhesive attachment (indicated between the parts at48) and/or seal that would also provide an adhesive connection between the stoma adapter20and the body fitment32.

Also, in the fourth embodiment, the stoma adapter20generally has a more conic shape, at least towards the distal end24, so that the flange is less pronounced.

As seen inFIGS.4B and40, the distal end24of the stoma adapter20may extend out past the stoma10and then return to attach to the body fitment32. Such a shape would allow the stoma adapter20to move axially with the stoma10without placing unwanted stress on the attachment to the body fitment32.

Formation of the stoma adapter20can be accomplished by a variety of methods. These include, but are not limited to, injection molding, blow molding and longitudinal seal bonding of flat sheet material to form a tube. The tube material may or may not, as desired, have gas barrier properties to contain or manage odor. The stoma adapter20material may or may not, as desired, have properties that reduce the friction of effluent flow along its length, in order to promote easier discharge of effluent. The stoma adapter20may or may not, as desired, have properties that improve ease of introduction into the bowel. These properties may be imparted by the material itself, by impregnating the material with specific additives intended to impart those properties to the material, or by application of one or more coatings to the appropriate surface(s) of the stoma adapter20.

The preferred cross-sectional shape of the stoma adapter20in the embodiments is circular, but in some cases, it may be desirable for the stoma adapter20to have a conic, but non-circular shape. It may also be desirable for the stoma adapter20to have a cross-sectional shape that closely approximates the shape of the inner surface of the bowel to ensure that it conforms to the bowel along the full length of the stoma adapter20. This may be accomplished by creating a custom shape for each stoma adapter20to match the wearer. It may also be accomplished by imparting elastic properties to the stoma adapter20that cause it to deform to match the shape of the bowel after introduction. These changes may be purely elastic, in which the stoma adapter20regains its original shape after removal. Or, the changes may be entirely plastic, in which the adapter20retains the shape of the inner surface of the bowel. Or, the changes may be a combination of elastic-plastic behavior, in which the stoma adapter20partially retains the shape of the bowel after removal. Materials for such a stoma adapter20include, but are not limited to, biocompatible materials of natural or synthetic origin, such as olefin plastics, polycarbonates, styrenes, flouropolymers, thermoplastic elastomers, polyurethanes, polyesters, cellulose polymers, alginates, chitosan and its derivatives, polyacrylonitriles, diene elastomers, polyamides, polyethers, polyvinyl alcohol, polyether block amides, polyimides, silicones, polyacrylates, polymethacrylates, ionomers, polyvinylacetate and its copolymers, polyvinylchloride, polyvinylidene chloride, and fluorinated polymers. Composite construction including one or more of the above and/or metallic elements such as springs, may also be desirable. Shape memory metals or polymers may be suitable for the shape recoverable embodiments illustrated later. Methods of formation of such a stoma adapter20may include, but are not limited to, any of injection molding, thermoforming, extrusion, casting, blow molding, sterolithography, or fused deposition, or selective laser sintering.

The properties of the stoma adapter20may vary depending on the design and the intended application. For example, a rigid stoma adapter20(as in the first to third embodiments) may be useful for holding the bowel open and to maintain a constantly open flow path for efficiently directing effluent from the bowel.

Alternatively, the stoma adapter20may be formed of thin, flexible material such a plastic film (as in the fourth embodiment, and a fifth embodiment illustrated inFIG.5). The flexible material may or may not have elastic properties, as desired. Use of a flexible material may be suitable for where compatibility with natural movements of the bowel is desired. The bowel typically changes its cross-sectional shape as a result of a variety of conditions. These include normal peristaltic motion, flexure of the abdominal wall, vigorous physical activity, and the passage of effluent through the bowel. A stoma adapter20made from thin, flexible material may be used where it is desired to present little or no hindrance to natural motion of the bowel.

A further aspect of the stoma adapter20is the creation of a seal between the bowel wall52and the stoma adapter20. The following embodiments illustrate certain seal principles. Although these embodiments illustrate seal features separately, the sealing arrangements may be combined, and any of the seal arrangements may be used with any of the preceding embodiments.

Referring toFIGS.6and7, in a further embodiment, the proximal end22of the stoma adapter20incorporates a seal50between the inner surface of the bowel wall52and the outer surface of the stoma adapter20. Because the stoma adapter20is configured not to obstruct the free flow of effluent in the discharge direction, and is not intended to be closed or to block flow, the intent of the seal50is merely to divert the flow of effluent into the stoma adapter20(as indicated by arrows54). The seal50does not have to withstand the pressure of effluent backing up inside the bowel. In the preferred embodiments, the seal50performs the function of flow diversion with a minimum level of pressure exerted on the bowel tissue. It is desirable to create a seal that conforms to the local shape and topography of the inner surface of the bowel wall52.

In the embodiment ofFIGS.6and7, the seal50is provided by a bolster56. The bolster56is optionally inflatable to expand into seal contact with the inner surface of the bowel wall52. Inflation fluid may be supplied from an external source58through an inflation capillary channel (not shown). The inflation pressure would be a minimum required to create an effective seal, to ensure that blood flow through the bowel and to local seal contact area would not be compromised.

Referring toFIGS.8A and8B, in a further embodiment, the seal50comprises two (or more) distinct inflatable sealing elements or bolsters56. The bolsters56are radially and/or axially displaced from each other. The bolsters56may be inflated to the same inflation pressure, or different inflation pressures. The bolsters56may be inflated from a common inflation port (optionally, with some inflation pressure regulator if the bolsters56are to be inflated to different inflation pressures), or from independent inflation ports to allow complete control over each respective inflation pressure. Two or more bolsters56may be desirable in certain applications.

With the embodiments ofFIGS.6-8, the inflation fluid may be a gas (such as air) or a liquid (such as saline), or a gel, or any suitable fluid that can be transferred from one volume to a second volume to expand the second volume. The inflation fluid may retain its properties, or it may set into a rigid or semi-rigid state after filling the inflatable bolster56.

Referring toFIGS.9A and9B, the inflation fluid could be or comprise a sealant material. Furthermore, the bolster56may be configured to permit the sealant to pass through the wall(s) of the bolster56to form a seal between the bolster56and the bowel wall52. For example, the bolster56may have small (e.g., microscopic) holes66in specific areas that contact the bowel wall52, in order to preferentially pass the sealant62(as indicated by arrows60) to the corresponding region of the bowel wall52, to fill any gaps (indicated by the sealant filling62inFIG.9B). Referring toFIGS.10A and10B, instead of an inflatable bolster56, the stoma adapter20comprises an annular foam ring64to contact the inner surface of the bowel wall52and create a seal. The foam ring64is optionally shaped to improve its sealing properties. The thickness of the foam, and/or the diameter of the foam, and/or the contact angle of the foam can also be adjusted to optimize the sealing characteristics. In the illustrated embodiment, the foam ring has a conical shape, presenting a funnel-like geometry to the flow of effluent. The inner and/or outer surface may be frusto-conical. Other shapes of foam ring64could be used as desired. For example, the foam ring could alternatively have a cylindrical annular shape, whose cross section is oriented generally perpendicular to the surface of the inner bowel wall52.

The properties of the foam may also be adjusted to improve the properties of the seal. The foam may be open or closed cell construction, depending on the requirements of the application. Elastic properties of the foam could be adjusted to ensure the proper balance between sealing pressure and seal performance.

Referring toFIG.10C, the bolster56may enclose a expanding foam element68. The preferred embodiment of the foam element68ris an annular ring, although other symmetrical or non-symmetrical shapes may be preferred for specific applications. The natural tendency of the foam element68to expand would inflate the bolster56and cause it to conform to the size and shape of the bowel wall52. As the foam element68expands, air or any other suitable inflation fluid would be drawn into the bolster56.

It is possible to control the response of the foam-filled bolster56by controlling the rate at which inflation fluid enters and exits the bolster56. This response could include, but not be limited to, inflation with little or no flow restriction and deflation with a high flow restriction.

Referring toFIG.11, in another embodiment, one or more elastomeric rings66located at the proximal end22of the stoma adapter20serve to hold the proximal end22of the tube in sealing contact with the inner surface of the bowel wall52. Two or more of these elastometric rings66could be axially displaced along the tube of the stoma adapter20. The elastometric rings66may optionally be of different diameters, to improve the adapters ability to effectively seal against a surface that is different in size from one ostomate to another, and which may change in size continually.

Referring toFIGS.12A,12B,12cand12D, in another embodiment, the proximal end22of the stoma adapter20is plastically deformable. In use, when inserting the stoma adapter20into the stoma10, the proximal end22is stretched circumferentially until it achieves conformal contact with the inner surface of the bowel wall52. Stretching of the proximal end22of the stoma adapter20could be achieved by means of an inflatable bolster56which would be removed after creation of the seal50. The function of the seal50could be enabled or enhanced by the application of a sealant or an adhesive (region70) to the contact area of the seal before introduction or during manufacture.

Another aspect of the stoma adapter20is retention in the stoma and/bowel. The following embodiments illustrate various retention principles. Although these embodiments illustrate retention features separately, the retention arrangements may be combined, and any of the retention arrangements may be used with any of the preceding embodiments.

In some applications, retention of the stoma adapter20in the bowel is significant for its function. In the case of a rigid or semi-rigid stoma adapter20, then it is possible to ensure retention of the proximal end22in the bowel by anchoring the stoma adapter20externally to the bowel. For example, attaching the distal end24of the stoma adapter20to the distal surface of the body fitment32, to the pouch30, or directly to the ostomate's peristomal skin12could achieve that anchoring function (as illustrated inFIGS.3a,3B,4A and4B).

In the case of a stoma adapter20that is constructed wholly or partially of thin, flexible material, it may be desirable to prevent the stoma adapter20from collapsing along its axis due to peristaltic forces or the force of expelled effluent. One method of ensuring retention of a flexible tubular stoma adapter20is to reinforce it in the axial direction without adversely affecting its ability to conform to the inner surface of the bowel wall52. The axial stiffness supports the proximal end24of the stoma adapter20in the same way that a rigid or semi-rigid stoma adapter.

Referring toFIGS.13A,13B and130, one means of providing axial stiffness to incorporate a multiplicity of buttress or reinforcing elements72on the outer or inner surface of the stoma adapter20. The reinforcing elements72are oriented generally parallel to the tubular axis of the stoma adapter20. The size, number, and placement of the reinforcing elements72would determine the axial stiffness of the stoma adapter20. However, because the individual reinforcing elements72are relatively compliant in the transverse direction, the tubular stoma adapter20would remain radially flexible (see arrows74aindicating flexing in the radial direction when squeezed; and arrows74brepresenting withstanding of an axial force).

Referring toFIGS.14A and14B, in another embodiment of this axial buttress or reinforcement approach, the surface of the stoma adapter20includes a multiplicity of tubes76(flexible capillaries) running length of the stoma adapter20. These tubes76are smaller in cross section than the main discharge passage34of the stoma adapter20, with cross section widths less than 25% of the cross section width of the discharge passage34. These tubes76can be formed from very soft material. In one form, the tubes76are additional components assembled to the stoma adapter20; in another form, the tubes76are integrally formed as part of the structure of the stoma adapter20itself. For example, the smaller tubes76are formed by selectively attaching together portions of adjacent layers78a,78bof the material forming the multi-layer wall78of the stoma adapter20. In use, inflation of the tubes76imparts axial rigidity to them, and therefore to the stoma adapter20. At the same time, the tubes76are compliant to local radial forces. The smaller tubes76could be inflated from the same source as that used to inflate a proximal seal50, or they may be inflated by a separate source, either after introduction into the bowel, during introduction, or before introduction.

Referring toFIGS.15a,15B and15C, in another embodiment, a helical spring80is used to impart an appropriate level of resistance to axial force while allowing a high level of radial compliance. In one form (FIG.15A), the spring80is mechanical in nature; that is, formed from an elastic material such as a metal or polymer. In another form (FIGS.15B and15C), the spring80is formed from a flexible tube82with a helical shape. The flexible tube82is attached to or incorporated into the stoma adapter20in the same manner as the tubes76ofFIGS.14A and14B. The flexible tube82would have no intrinsic strength when not inflated (FIG.15B). When inflated (FIG.15C) to a desired inflation pressure through inflation port84, the flexible tube82exhibits the desired level of axial stiffness yet maintaining radial compliance.

In another embodiment (not shown), longitudinal buttress or reinforcing elements could be made of a material with different physical properties than the main tube of the stoma adapter20. Such reinforcing elements could, for example, be incorporated into the stoma adapter20by co-extrusion.

In another embodiment (not shown) the axial stiffness of the stoma adapter20could be enhanced by selectively coating the stoma adapter20in specific areas with materials that modify the properties of the tube76,82by either imparting their own stiffness to enhance the stiffness of the entire structure or by locally modifying the properties of the stoma adapter20material itself.

Another aspect of the stoma adapter20is insertion in the stoma10and/bowel. The following embodiments illustrate various insertion principles. Although these embodiments illustrate insertion features separately, the insertion arrangements may be combined, and any of the insertion arrangements may be used with any of the preceding embodiments.

If the stoma adapter20is rigid, or at least semi-rigid, introduction of the proximal end22into the bowel is likely to require a degree of radial stretching or compliance of the bowel at one or more locations along the length of the stoma adapter20.FIGS.16A and16Billustrate an idea of collapsing cross-section configurations that may be employed to minimize (or at least reduce) the amount of compliance or stretching of the bowel during introduction of the stoma adapter20. By creating a bistable cross section88, it is possible to more easily introduce the proximal end22of the stoma adapter20in its collapsed configuration, and then expand it to its final configuration after insertion. In one embodiment (FIG.16A), the collapsed configuration of the stoma adapter20is, in cross section, two adjacent semi-circular shapes90aand90b. Upon insertion, the stoma adapter20is expanded by driving out the inner semi-circular shape90buntil the stoma adapter expands, in cross section, into a complete loop92(e.g., circle) after introduction. In another embodiment (FIG.16B), the collapsed configuration of the stoma adapter20has a fluted cross section, with flute segments or channels94that give the stoma adapter20a reduced overall diameter. After insertion, the fluted cross-section is expanded to its final circular shape96.

Expansion of the collapsed configuration after introduction of the proximal end22into the stoma10could be accomplished by means of a mandrel (not shown) which could be inserted into the stoma adapter20and then expanded to initiate the shape change. Such a mandrel could be mechanical in nature, but a desirable embodiment may be an inflatable cylinder which could be inflated to the appropriate diameter to expand the stoma adapter20to its final shape. In another embodiment, elements made of a shape-memory material expand after introduction and exposure to body temperature, causing the stoma adapter20to expand to its final shape.

Referring toFIG.17, if the stoma adapter20is non-rigid or flexible, at least in the axial direction (e.g., as in the embodiments ofFIGS.14A,14B,15B and15Cwhen not inflated), it may be desirable to employ an insertion device100to aid insertion of the proximal end22into the stoma10. To improve ease of insertion, the cross section of the stoma adapter20is preferably reduced or minimized, especially at the proximal end22. This is accomplished by selectively folding and pleating the flexible material of the stoma adapter20into a cross section size and shape that is more easily introduced into the bowel. Once introduced, the material of the stoma adapter20may be unfolded and deployed by mechanical means or pneumatic means, for example using the same component as the insertion device100, or using a different component (not shown). If required, the insertion device100used to assist in the introduction of the stoma adapter20into the bowel could be removed. The stoma adapter20may be held captive in its folded state by a constricting element102that can be removed or released after introduction into the stoma10. The constricting element102may be arranged at the proximal end22of the stoma adapter20.

Referring toFIG.18, one form of such a constricting element102may be made of biocompatible material that dissolves or is absorbed shortly after introduction of the stoma adapter20into the stoma10. For example, the constricting element102may dissolve upon contact with stomal fluid. In the illustrated form, the constricting element102is a tightly-formed band or collar made of the biocompatible material.

Referring toFIGS.19A and19B, in another embodiment the constricting element102is in the form of a conical tip for holding the stoma adapter20in its folded state. The cone could be formed from a dissolvable material, as described above. Additionally or alternatively, an insertion device100may be employed to introduce stoma adapter20and dislodge the constricting element (conical tip)102. For example, the constricting element (conical tip)102may be dislodged when the stoma adapter20reaches its fully inserted position, and the constricting element (conical tip)102then bears the full insertion force applied through the insertion device100. The insertion device100would then be withdrawn through the distal end24of the stoma adapter20.

Materials for these constricting elements102include, but are not limited to, biocompatible materials of natural or synthetic origin such as polysaccharides, cellulosics such as hydroxypropylmethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, chitosan and its derivatives, gelatin, alginates, sodium alginate, xanthan gum, tragacantha, guar gum, acacia gum, arabic gum, polyacrylic acid and its copolymers, polypeptides, sulfonated polymers, polyacrylamide and its copolymers, polyvinyl pyrrolidone, polyvinyl ether, polyvinyl alcohol, polyethylene, glycol, x, methylmethacrylate copolymers, and carboxyvinyl polymers and copolymers.

Referring toFIGS.20A,20B and20C, in another embodiment, the stoma adapter20could be partially inverted into a folded shape (FIG.20A) and its proximal end22temporarily closed with a constricting element or tip102. In use, the stoma adapter20in its inverted condition is partially introduced into the stoma10(FIG.20A), and then a moderate amount of air or saline is applied from a pressurization source104to pressurize the distal end of the stoma adapter. As illustrated inFIGS.20B and20C, the pressure causes the stoma adapter20to unfold, and thus introduce the proximal end22into the bowel as the stoma adapter20unfolds.

It will be appreciated that the stoma adapter of the present invention can provide effluent guidance and skin protection for all types of stoma, but is especially suitable for recessed or flush stomas, which are difficult to manage. The stoma adapter may be independent of the ostomy appliance with which it is used, or the stoma adapter may be attachable to the ostomy appliance or an integral part of the ostomy appliance. The stoma adapter may take many different rigid or non-rigid forms, depending on the desired characteristics.

Many modifications may be made to the preferred embodiments used without departing from the claim coverage of the invention.