Wound dressing

• US 9,956,121 B2
• Filed: 04/22/2014
• Issued: 05/01/2018
• 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): KLEIN, BENJAMIN JACOB
• Application Number:
  US14/259,026
• Publication Number:
  US 20140228791A1
• Time in Patent Office: 1,470 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 13/0206 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 13/025 having a special distribution arrangement of the adhesive
• CPC Class Codes: A61F 13/0253 characterized by the adhesive material
• 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 2013/0028 applying of mechanical pressure; passive massage
• CPC Class Codes: A61F 2013/00536 for draining or irrigating wounds
• CPC Class Codes: A61M 1/90 Negative pressure wound therapy devices, i.e. devices for applying suction to a wound to promote healing, e.g. including a vacuum dressing
• CPC Class Codes: A61M 1/912 Connectors between dressing and drainage tube
• 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 1/985 the dressing itself forming the collection container
• 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 an absorbent layer for absorbing wound exudate, a liquid impermeable, gas permeable filter layer over the absorbent layer, a cover layer comprising at least one orifice and a first liquid and gas permeable transmission layer underlying the absorbent layer. The transmission layer is in fluid communication with the filter layer.

Claims

1. A system for applying negative pressure to a wound site, the system comprising:

a wound dressing comprising;

a perforated wound contact layer for contacting the wound site;

a first transmission layer for distributing negative pressure overlying the wound contact layer;

an absorbent layer for absorbing wound exudate via the wound contact layer and the first transmission layer, the absorbent layer overlying the first transmission layer;

a second transmission layer overlying and in direct contact with the absorbent layer, the second transmission layer adapted to distribute negative pressure;

a cover layer overlying the second transmission layer, the cover layer comprising at least one aperture and further comprising a border region and a central region, wherein the cover layer is directly secured to the wound contact layer in the border region;

a filter provided over the second transmission layer and positioned at the at least one aperture in the cover layer, and;

a negative pressure source configured to be in fluid communication with the at least one aperture in the cover layer via a conduit, the negative pressure source configured to generate negative pressure under the cover layer.

2. The system of claim 1, wherein a peripheral region of the first transmission layer and a peripheral region of the second transmission layer are pinched together to provide a fluid communication path around a peripheral edge of the absorbent layer.

3. The system of claim 2, wherein the negative pressure source is configured to communicate negative pressure to the wound site via at least one fluid transmission path passing through the perforations in the wound contact layer and through the peripheral region of the first transmission layer and the peripheral region of the second transmission layer alongside at least one edge of the absorbent layer.

4. The system of claim 1, wherein the filter is in fluid communication with the absorbent layer.

5. The system of claim 1, wherein the wound dressing comprises a square shape having equal side lengths with rounded corner regions.

6. The system of claim 1, wherein the at least one aperture of the cover layer is positioned in the central region of the upper surface of the cover layer.

7. The system of claim 1, further comprising an adhesive provided on an underside of the wound dressing.

8. The system of claim 7, further comprising a releasable protective layer on a lower surface of the wound contact layer.

9. The system of claim 1, wherein the central region of the cover layer is a central raised region, and wherein the second transmission layer acts as a manifold and a diffuser to help spread the negative pressure generated by the pump.

10. The system of claim 1, wherein the filter comprises a hydrophobic material.

11. The system of claim 1, wherein the filter comprises PTFE.

12. The system of claim 1, the filter comprising a first filter layer and a secondary filter layer.

13. The system of claim 1, wherein the filter is secured to the cover layer with an adhesive.

14. The system of claim 1, wherein the wound dressing is disposable after a single use.

15. The system of claim 14, wherein the negative pressure source is reusable.

16. The system of claim 1, wherein the wound contact layer and the cover layer hold the wound dressing together.

17. The system of claim 1, wherein the filter is provided under the cover layer.

18. The system of claim 1, wherein the filter is provided over the cover layer.