Wound dressing

• US 9,844,475 B2
• Filed: 05/31/2016
• Issued: 12/19/2017
• Est. Priority Date: 11/21/2007
• Status: Active Grant

• Current Assignee: Smith & Nephew PLC
• Original Assignee: Smith & Nephew PLC
• Inventors: Hartwell, Edward Yerbury
• Primary Examiner(s): Zalukaeva, Tatyana
• Assistant Examiner(s): KLEIN, BENJAMIN JACOB
• Application Number:
  US15/169,461
• Publication Number:
  US 20160270967A1
• Time in Patent Office: 567 Days
• CPC Class Codes: A61F 13/00063 comprising medicaments or additives, e.g. odor control, PH control, debriding, antimicrobic drug delivery dressings A61K9/70; chemical aspect of the additives A61L15/00
• CPC Class Codes: A61F 13/01029 made of multiple layers
• CPC Class Codes: A61F 13/01046 Air-vapor permeability
• CPC Class Codes: A61F 13/02 Adhesive bandages or dressings
• CPC Class Codes: A61F 13/0206 with absorbent fibrous layers, e.g. woven or non-woven absorbent pads or island dressings
• CPC Class Codes: A61F 13/0209 comprising superabsorbent material
• CPC Class Codes: A61F 13/022 having more than one layer with different fluid retention characteristics
• CPC Class Codes: A61F 13/0226 characterised by the support layer
• CPC Class Codes: A61F 13/0246 characterised by the skin-adhering layer
• CPC Class Codes: A61F 13/05 specially adapted for use with sub-pressure or over-pressure therapy, wound drainage or wound irrigation, e.g. for use with negative-pressure wound therapy [NPWT]
• CPC Class Codes: A61F 2013/00246 in a special way pervious to air or vapours
• CPC Class Codes: A61F 2013/00536 for draining or irrigating wounds
• CPC Class Codes: A61M 1/71 Suction drainage systems containers therefor A61M1/60, A61M1/64; negative pressure wound therapy systems A61M1/90
• CPC Class Codes: A61M 1/78 Means for preventing overflow or contamination of the pumping systems combined with drainage containers A61M1/60
• CPC Class Codes: A61M 1/784 by filtering, sterilising or disinfecting the exhaust air, e.g. swellable filter valves
• CPC Class Codes: A61M 1/882 Draining devices provided with means for releasing antimicrobial or gelation agents in the drained fluid
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/962 having pumping means on the suction site, e.g. miniature pump on dressing or dressing capable of exerting suction
• CPC Class Codes: A61M 1/964 having venting means on or near the dressing
• CPC Class Codes: A61M 1/985 the dressing itself forming the collection container
• CPC Class Codes: A61M 2205/7527 : liquophilic, hydrophilic
• CPC Class Codes: A61M 2205/7536 : allowing gas passage, but preventing liquid passage, e.g. liquophobic, hydrophobic, water-repellent membranes
• CPC Class Codes: A61M 27/00 : Drainage appliance for wounds or the like , i.e. wound drains, implanted drains negative pressure wound therapy devices A61M1/90; implements for holding wound open A61B17/02 ; middle ear drainage A61F11/202

Abstract

A method and apparatus are disclosed for dressing a wound. The apparatus comprises a sealing layer comprising at least one orifice, an absorbent layer over the sealing layer, absorbing wound exude and a liquid impermeable, gas permeable filter layer over the absorbent layer.

Claims

1. A wound dressing for the treatment of a wound by applying negative pressure to the wound, the wound dressing comprising:

a wound contact layer comprising a plurality of perforations through the wound contact layer that allow for fluid to pass there through;

a porous layer above the wound contact layer;

a sealing material in communication with the porous layer, wherein the sealing material is gas impermeable;

an absorbent layer configured to form a reservoir for fluid removed from the wound;

a cover layer covering the absorbent layer, wherein the cover layer extends over the absorbent layer into an edge region that is secured to the wound contact layer; and

a pump positioned between the cover layer and the wound contact layer and within the absorbent layer, the pump separated from the porous layer by the sealing material, the pump configured to apply negative pressure to the wound and configured to draw fluid from the wound through the wound contact layer and the porous layer and into the absorbent layer.

2. The wound dressing of claim 1, wherein gaseous components of the fluid collected and stored by the absorbent layer are exhausted through the cover layer.

3. The wound dressing of claim 1, further comprising a filter layer which permits air to be exhausted from the wound dressing.

4. The wound dressing of claim 1, wherein the cover layer comprises a high moisture vapor permeable material configured to allow moisture to transpire through the cover layer.

5. The wound dressing of claim 1, wherein the wound contact layer comprises an upper surface and a lower surface, and further comprising an adhesive on the lower surface, wherein the adhesive is configured to adhere the wound contact layer to the wound.

6. The wound dressing of claim 1, wherein the absorbent layer comprises a synthetic superabsorbing material.

7. The wound dressing of claim 1, wherein the porous layer disposed over the wound contact layer is configured to distribute negative pressure, through the wound contact layer, equally over the entire portion of the wound site being treated.

8. The wound dressing of claim 1, wherein the porous layer is provided directly over the plurality of perforations in the wound contact layer.

9. The wound dressing of claim 1, wherein the porous layer comprises a reticulated material.

10. The wound dressing of claim 1, wherein the porous layer comprises a non-woven material.

11. The wound dressing of claim 1, wherein the porous layer comprises reticulated foam.

12. The wound dressing of claim 1, further comprising an opening in the sealing material, wherein the pump is in communication with the porous layer through the opening in the sealing material.

13. The wound dressing of claim 1, wherein the sealing material extends across the width of the wound dressing.

14. The wound dressing of claim 3, wherein the filter layer comprises an odor trapping material.

15. The wound dressing of claim 3, wherein the filter layer comprises a gas permeable and liquid impermeable material.

16. The wound dressing of claim 3, wherein the cover layer comprising at least one hole and the filter layer is configured to cover the at least one hole in the cover layer, wherein air exhausted from the pump is configured to pass through the filter layer and the at least one hole in the cover layer.

17. The wound dressing of claim 3, wherein the filter layer is configured to prevent pathogens from being exhausted from the wound dressing.

18. A wound dressing for the treatment of a wound by applying negative pressure to the wound, the wound dressing comprising:

a wound contact layer comprising a plurality of perforations through the wound contact layer that allow for fluid to pass there through;

a porous layer above the wound contact layer;

an absorbent layer configured to form a reservoir for fluid removed from the wound, wherein the absorbent layer is above the porous layer;

a cover layer covering the absorbent layer, wherein the cover layer extends over the absorbent layer into an edge region that is secured to the wound contact layer;

a pump positioned between the cover layer and the wound contact layer and within the absorbent layer, the pump configured to apply negative pressure to the wound and configured to draw fluid from the wound through the wound contact layer and the porous layer and into the absorbent layer; and

a filter layer which permits air to be exhausted from the wound dressing, wherein air exhausted from the pump is configured to pass through the filter layer while allowing liquid to be absorbed and retained within the wound dressing and while negative pressure is maintained by the wound dressing.

19. The wound dressing of claim 18, wherein gaseous components of the fluid collected and stored by the absorbent layer are exhausted through the cover layer.

20. The wound dressing of claim 18, wherein the cover layer comprises a high moisture vapor permeable material configured to allow moisture to transpire through the cover layer.

21. The wound dressing of claim 18, wherein the cover layer comprises at least one hole and the filter layer is configured to cover the at least one hole in the cover layer, wherein air exhausted from the pump is configured to pass through the filter layer and the at least one hole in the cover layer.

22. The wound dressing of claim 18, wherein the wound contact layer comprises an upper surface and a lower surface, and further comprising an adhesive on the lower surface, wherein the adhesive is configured to adhere the wound contact layer to the wound.

23. The wound dressing of claim 18, wherein the filter layer comprises an odor trapping material.

24. The wound dressing of claim 18, wherein the filter layer comprises a gas permeable and liquid impermeable material.

25. The wound dressing of claim 18, wherein the filter layer is configured to prevent pathogens from being exhausted from the wound dressing.