US-12622816-B2 - Dressings for reduced tissue ingrowth

Abstract

Dressings are provided herein having a manifold and a biopolymer layer. The configuration and/or compressibility of the manifold and the biopolymer layer can allow for reduced tissue ingrowth and promote wound healing. Methods of making and using the dressings are also provided herein.

Inventors

• Prathamesh Madhav KHARKAR
• Kristine M. KIESWETTER
• Alexander WAITE

Assignees

• SYSTAGENIX WOUND MANAGEMENT, LIMITED
• KCI LICENSING, INC.

Dates

Publication Date

20260512

Application Date

20230726

Claims (20)

1. 1 . A dressing for use in negative pressure wound therapy comprising: a manifold having a wound facing side, a non-wound facing side opposite the wound facing side, and outer edges between the wound facing and non-wound facing sides; and a first biopolymer layer coupled to the manifold; wherein the manifold has a compressibility index value greater than a dry state compressibility index value of the first biopolymer layer, and less than a hydrated state compressibility index value of the first biopolymer layer.
2. 2 . The dressing of claim 1 , wherein the first biopolymer layer is configured to be in contact with the wound facing side and at least a portion of the outer edges of the manifold, and further configured to reduce or prevent the ingrowth of tissue into said portion of the outer edges during wound therapy.
3. 3 . The dressing of claim 1 , wherein the first biopolymer layer is configured to contact said portion of the outer edges only during wound therapy, such as negative pressure wound therapy.
4. 4 . The dressing of claim 1 , wherein the first biopolymer layer is separable from the manifold.
5. 5 . The dressing of claim 1 , wherein the compressibility index value of the manifold is 10 to 50.
6. 6 . The dressing of claim 1 , wherein the dry state compressibility index value of the first biopolymer layer is zero to 35 and the hydrated state compressibility index value of the first biopolymer layer is 65 to 90.
7. 7 . The dressing of claim 1 , wherein the first biopolymer layer comprises a biological material selected from the group consisting of heparin, collagen, gelatin, hyaluronic acid, chitosan, cellulose, a cellulose derivative, alginate, fibrin, silk, carrageenan, chondroitin sulfate, agarose, keratin, dextran, keratan sulfate, heparan sulfate, fibronectin, laminin, and a combination thereof.
8. 8 . The dressing of claim 1 , wherein the first biopolymer layer comprises a synthetic polymer selected from the group consisting of polycaprolactone, polylactic acid, polyglycolic acid, polydioxanone, poly(lactic-co-glycolic acid), and polyhydroxybutyrate, polyhydroxyvalerate and a combination thereof.
9. 9 . The dressing of claim 1 , wherein the first biopolymer layer comprises collagen; and also comprises oxidized non-regenerated cellulose and/or oxidized regenerated cellulose.
10. 10 . The dressing of claim 1 , wherein the first biopolymer layer comprises an antimicrobial agent.
11. 11 . The dressing of claim 1 , wherein the first biopolymer layer is perforated and/or is printed on with text and/or symbols.
12. 12 . The dressing of claim 1 , wherein the first biopolymer layer has a thickness of 0.1 cm to 5 cm.
13. 13 . The dressing of claim 1 , wherein the first biopolymer layer has a density 0.01 g/cm3 to 0.06 g/cm3.
14. 14 . The dressing of claim 1 , further comprising a second biopolymer layer, wherein the second biopolymer layer is interposed between the manifold and the first biopolymer layer.
15. 15 . The dressing of claim 14 , wherein the second biopolymer layer has a dry state compressibility index value greater than the dry state compressibility index value of the first biopolymer layer.
16. 16 . The dressing of claim 1 , wherein the manifold comprises silicone, polyvinyl alcohol, a combination thereof, or foam.
17. 17 . The dressing of claim 1 , wherein the manifold has a thickness of 0.5 cm to 8 cm.
18. 18 . The dressing of claim 1 , wherein an area of overlap between the manifold and the first biopolymer layer is 0.01 cm to 5 cm.
19. 19 . The dressing of claim 1 , wherein the manifold and the first biopolymer layer together have a trapezoidal cross-section having an inclined angle of 20 to 85 degrees.
20. 20 . The dressing of claim 1 , wherein the manifold is perforated or has one or more partial cuts.

Description

RELATED APPLICATION This application is a continuation of U.S. patent application Ser. No. 17/269,589, filed Feb. 19, 2021, which claims the benefit of U.S. National Stage Entry of PCT/US2019/038273, filed Jun. 20, 2019, which claims the benefit, under 35 U.S.C. § 119(e), of the filing of U.S. Provisional Patent Application Ser. No. 62/723,837, entitled “Dressings For Reduced Tissue Ingrowth,” filed Aug. 28, 2018, which is incorporated herein by reference for all purposes. TECHNICAL FIELD The invention set forth in the appended claims relates generally to tissue treatment systems and more particularly, but without limitation, to dressings for reduced tissue ingrowth. BACKGROUND Clinical studies and practice have shown that reducing pressure in proximity to a tissue site can augment and accelerate growth of new tissue at the tissue site. The applications of this phenomenon are numerous, but it has proven particularly advantageous for treating wounds. Regardless of the etiology of a wound, whether trauma, surgery, or another cause, proper care of the wound is important to the outcome. Treatment of wounds or other tissue with reduced pressure may be commonly referred to as “negative-pressure therapy,” but is also known by other names, including “negative-pressure wound therapy,” “reduced-pressure therapy,” “vacuum therapy,” “vacuum-assisted closure,” “sub-atmospheric pressure” and “topical negative-pressure,” for example. Negative-pressure therapy may provide a number of benefits, including proliferation of dermal, epithelial and subcutaneous tissues, improved interstitial fluid and blood flow, and macroscopic and micro-deformation of tissue at a wound site. Together, these benefits can increase development of granulation tissue and reduce healing times. There is also widespread acceptance that cleansing a tissue site can be highly beneficial for new tissue growth. For example, a wound or a cavity can be washed out with a liquid solution for therapeutic purposes. These practices are commonly referred to as “irrigation” and “lavage” respectively. “Instillation” is another practice that generally refers to a process of slowly introducing fluid to a tissue site and leaving the fluid for a prescribed period of time before removing the fluid. For example, instillation of topical treatment solutions over a wound bed can be combined with negative-pressure therapy to further promote wound healing by loosening soluble contaminants in a wound bed and removing infectious material. As a result, soluble bacterial burden can be decreased, contaminants removed, and the wound cleansed. While the clinical benefits of negative-pressure therapy and/or instillation therapy are widely known, improvements to therapy systems, components, and processes may benefit healthcare providers and patients. BRIEF SUMMARY New and useful systems, apparatuses, and methods for reducing tissue ingrowth in a negative-pressure therapy environment are set forth in the appended claims. Illustrative embodiments are also provided to enable a person skilled in the art to make and use the claimed subject matter. For example, in some embodiments, dressings are provided that reduce the potential of tissue ingrowth while also addressing challenges to wound healing, such as high levels of matrix metalloproteases (MMPs) and stimulating granulation tissue formation. More generally, dressings are provided comprising a manifold and a biopolymer layer. In some embodiments, the manifold has a wound facing side, a non-wound facing side opposite the wound facing side, and outer edges between the wound facing and non-wound facing sides; and the biopolymer layer is configured to be in contact with the wound facing side and at least a portion of the outer edges of the manifold, and further configured to reduce or prevent the ingrowth of tissue into said portion of the outer edges during negative pressure wound therapy. Additionally or alternatively, in other example embodiments the biopolymer layer may have a longer length and/or a larger surface area than the manifold. In further embodiments, dressings are provided having a manifold and a biopolymer layer coupled to the manifold, wherein the manifold has a compressibility index value greater than a dry state compressibility index value of the biopolymer layer, and less than a hydrated state compressibility index value of the biopolymer layer. Methods of making the dressings are also provided herein, wherein some example embodiments include contacting at least a portion of the manifold with a biopolymer slurry in aqueous base; and freeze drying the manifold and the biopolymer slurry to form a biopolymer layer coupled to the manifold. Additionally, in other example embodiments, methods of making the dressings further include perforating the manifold or partially cutting the manifold to provide one or more removable parts. This may allow customization of the manifold for end use. Methods of using the dressings for treatin