Wound contacting members and methods

• US 10,245,185 B2
• Filed: 06/07/2012
• Issued: 04/02/2019
• Est. Priority Date: 06/07/2011
• Status: Active Grant

• Current Assignee: Smith & Nephew PLC
• Original Assignee: Smith & Nephew PLC
• Inventors: Hicks, John Kenneth, Huddleston, Elizabeth Mary
• Primary Examiner(s): Mensh, Andrew J
• Application Number:
  US14/124,613
• Publication Number:
  US 20140296804A1
• Time in Patent Office: 2,490 Days
• Field of Search: 604317
• 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 2013/00174 possibility of applying pressure
• CPC Class Codes: A61F 2013/0028 applying of mechanical pressure; passive massage
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/916 specially adapted for deep wounds

Abstract

Wound contacting members and methods, apparatuses, systems and kits incorporating the same are disclosed. The wound contacting members offer improved performance in terms of preventing or inhibiting tissue in-growth and improving tissue granulation growth. The wound contacting members may be used in negative pressure wound therapy (NPWT) applications.

Claims

1. A wound contacting member for negative pressure wound therapy (NPWT) selected to reduce pain upon removal from a wound, comprising:

a foam, the foam comprising;

a network of foam strut elements separated by pores, at least 95% of the strut elements comprising a thickness of between 0.007 and 0.5 mm;

wherein one or more foam strut elements comprise a thickness of 0.23 mm or more; and

wherein at least 90% of the pores comprise a diameter of between 2.3 and 5.5 mm.

2. The wound contacting member of claim 1, wherein the wound contacting member has a pore count of between 5 and 25 ppi.

3. The wound contacting member of claim 1, wherein at least 10% of the strut elements have a thickness of 0.23 mm or more.

4. The wound contacting member of claim 1, wherein the wound contacting member has a compressive strain at −

120 mmHg of between 50±

5% and 90%±

5%.

5. The wound contacting member of claim 1, wherein the strut elements have a total surface area of between 30 and 150 mm² in a 126 mm³ volume.

6. The wound contacting member of claim 1, wherein the wound contacting member promotes granulation tissue growth at a wound bed simultaneously with the prevention or reduction of tissue in-growth into the wound contacting member.

7. The wound contacting member of claim 1, wherein the wound contacting member has a density between 0.03 and 0.04 g·

cm<sup>−

3</sup>.

8. An apparatus for treating wounds in a human or animal subject by negative pressure wound therapy (NPWT), comprising:

the wound contacting member of claim 1; and

a cover member configured to form a sealed enclosure around the wound contacting member when the wound contacting member is applied to a wound bed.

9. The apparatus of claim 8, further comprising a connection device for placing the enclosure in fluid communication with a vacuum source.

10. A method for treating a wound, comprising applying the wound contacting member of claim 1 to a wound bed.

11. The method of claim 10, further comprising applying a cover over the wound contacting member to form a sealed enclosure.

12. The method of claim 11, further comprising the step of applying negative pressure wound therapy (NPWT) to the wound bed.

13. The method of claim 10, further comprising promoting granulation tissue growth at the wound bed simultaneously with preventing or reducing tissue in-growth into the wound contacting member.

14. The method of claim 12, comprising applying negative pressure to the wound for at least 72 hours in the range of −

40 mmHg to −

200 mmHg, the negative pressure and the wound contacting member promoting the growth of granulation tissue at the wound, wherein the negative pressure causes the wound contacting member to compress to decrease a void volume and increase a strut volume.

15. The method of claim 12, further comprising removing the cover and the wound contacting member from the wound, wherein a force required to remove the wound contacting member from the wound is less than 5 mN.

16. The method of claim 12, wherein the application of negative pressure to the wound causes the wound contacting member to indent into tissue of the wound by 950±

50 μ

m to 1000±

50 μ

m.

17. The method of claim 12, wherein prior to applying negative pressure, the wound contacting member has a pore volume of 90±

5% to 98±

5% of the total volume, and after applying negative pressure for at least 72 hours, the wound contacting member has a pore volume of 70±

5% to 90±

5% of the total volume.