Seal for controlled evacuation ostomy appliance
View Patent ↗A controlled evacuation ostomy appliance comprises a membrane that is urged into sealing engagement with a stoma, by the generation of radial tension in the membrane. A tensioning device applies tension, with respect to the stoma, at one or more positions that are (i) outboard of the periphery of the projecting portion of the stoma, and/or (ii) between the level of the peristomal skin and the level of the most projecting part of the stoma. Tension limiting means are disclosed. The membrane may be gas-permeable to allow flatus to be vented.
1. A controlled evacuation ostomy appliance for controlling the discharge from a wearer's stoma comprising:
a. a frame attachable to the wearer and positionable around the stoma, said frame having a stomal aperture;
b. a flexible film-like membrane located inside said frame and extending across at least part of the stomal aperture, said membrane being configured for contacting the stoma and for obstructing the discharge of at least solid body waste therefrom; and
c. tensioning means for applying tension to said membrane, said tensioning means securing said membrane to said frame and having a closed loop shape, said tensioning means being secured to said membrane radially outside the stoma's periphery and between peristomal skin and upper surface of the stoma, said tensioning means applying tension to said membrane by drawing the membrane into a concave configuration around the stoma by pulling said membrane against the stoma so as to obstruct discharge from the stoma.
2. The controlled evacuation ostomy appliance according to claim 1 , wherein the tensioning means is adjustable for adjusting the magnitude of the tension in the membrane.
3. The controlled evacuation ostomy appliance according to claim 1 , wherein the membrane is not under substantial tension prior to fitting to a stoma, the membrane being configured such that entry of the stoma into the stomal aperture presses against the membrane in such a manner that the tensioning means and stoma together tension the membrane.
4. The controlled evacuation ostomy appliance according to claim 1 , wherein said tensioning means has a shape selected from: circular; and non-circular.
5. The controlled evacuation ostomy appliance according to claim 1 , further comprising a deodorizing filter on the opposite side of the membrane to the stomal aperture.
6. The controlled evacuation ostomy appliance according to claim 1 , wherein at least a portion of the membrane is gas-permeable to allow flatus to pass from the stoma through the membrane.
7. The controlled evacuation ostomy appliance according to claim 6 , wherein the permeable portion of the membrane comprises a phase separator allowing gas to pass therethrough while obstructing the passage of solid) and/or liquid body waste.
8. The controlled evacuation ostomy appliance according to claim 7 , wherein the phase separator comprises one or more selected from: an activated charcoal filter; open cell foam; an expanded PTFE block; and a composite membrane comprising multiple layers defining a tortuous gas flow path therethrough.
9. The controlled evacuation ostomy appliance according to claim 1 , wherein the membrane comprises a tension limiter.
10. The controlled evacuation ostomy appliance according to claim 9 , wherein the tension limiter comprises a frangible support for holding the membrane in an artificially contracted state, such that upon the tension reaching a breaking threshold, the frangible connection breaks to release the artificially contracted state of the membrane.
11. The controlled evacuation ostomy appliance according to claim 9 , wherein the tension limiter comprises a constant force spring member.
12. The controlled evacuation ostomy appliance according to claim 1 , further comprising a shape defining member for pressing against the membrane on the opposite side to the stoma, for defining a shape that is not possible by applying tension alone.
13. The controlled evacuation ostomy appliance according to claim 12 , wherein the shape defining member comprises a projection for defining a central bulge in the membrane for at least partly entering the mouth of the stoma.
14. The controlled evacuation ostomy appliance according to claim 13 , further comprising a support for the shape defining member.
15. The controlled evacuation ostomy appliance according to claim 14 , wherein the support comprises a second tensioned membrane.
16. The controlled evacuation ostomy appliance according to claim 1 , further comprising a releasable coupling for enabling the tensioning device to be detachable.