Wound dressing devices and methods
Inventors
Assignees
Providence Health System Oregon • HemCon Medical Technologies Inc
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Publication Number
US-9205170-B2
Publication Date
2015-12-08
Expiration Date
Abstract
The present invention provides an absorbent wound dressing assembly that can be used to stanch, seal, or stabilize a site of tissue injury, tissue trauma, or tissue access. The wound dressing assembly is flexible so that it can be adapted and used to fit in narrow and small wound sites. Generally the wound dressing assembly comprises a flexible carrier material that is impregnated with a non-mammalian material for control of severe bleeding. The preferred non-mammalian material is poly [β-(1→4)-2-amino-2-deoxy-D-glucopyranose] more commonly referred to as chitosan.
Core Innovation
The invention is a hemostatic article that includes a nonwoven mesh composed of fibers of a polymeric material, where the polymeric material is a blend of rayon and polyester. A dried chitosan solution forms an interpenetrating network in the form of webs anchored among various fibers of the polymeric material, and the dried chitosan solution has a moisture content of less than 4.36 weight percent.
The disclosed wound dressing assembly is flexible and absorbent, with the chitosan forming web-like films or membranes in the fiber interstices while retaining voids for permeability. This structure is described as promoting blood-cell accumulation and coagulation while maintaining permeability for blood flow. The article is characterized by specified permeability to blood and Gurley stiffness value to achieve flexibility and absorptive performance.
The chitosan used is described as non-mammalian poly[β-(1→4)-2-amino-2-deoxy-D-glucopyranose], with stated parameters including molecular weight, degree of deacetylation, and viscosity, together with solution composition and optional use of acidity and/or an adhesive layer. The document describes manufacturing approaches based on applying chitosan solution or coating chitosan powder to the nonwoven carrier and removing excess prior to drying, followed by packaging and sterilization.
Claims Coverage
The independent claim defines a hemostatic article having a rayon/polyester nonwoven mesh with an anchored dried chitosan interpenetrating web network and specified moisture, blood permeability, and Gurley stiffness. The dependent claims refine blend ratios and quantitative chitosan parameters, and at least one dependent expands the article into a wound dressing assembly by adding an adhesive layer.
Rayon/polyester nonwoven mesh hemostatic article with anchored dried chitosan web network
A hemostatic article comprising a nonwoven mesh composed of fibers of a polymeric material, wherein the polymeric material is a blend of rayon and polyester; and an interpenetrating network of a dried chitosan solution, wherein the interpenetrating network is in the form of webs anchored among various fibers of the polymeric material and wherein the dried chitosan solution has a moisture content of less than 4.36 weight percent; wherein the hemostatic article has a permeability to blood (mean flow rate) and a Gurley stiffness value.
Overall claim coverage centers on the combination of a rayon/polyester nonwoven mesh with an interpenetrating anchored dried chitosan web network having low moisture, together with defined blood permeability and Gurley stiffness. Dependent claims further narrow quantitative blend and chitosan parameters and include an embodiment as a wound dressing assembly via an adhesive layer.
Stated Advantages
Promoting blood-cell accumulation and coagulation while maintaining permeability for blood flow.
Providing flexibility via Gurley stiffness performance within a specified range.
Providing permeability to blood within a specified mean flow rate range.
Providing absorbent wound dressing performance characterized by specified performance metrics described in the document.
Documented Applications
Use as a hemostatic article and as a wound dressing assembly for controlling severe bleeding/hemostasis in an injury model described as a porcine deep, narrow entry injury model (axillosubclavian injury).
Documented comparative evaluation including SEM-based blood cell accumulation and controlled hemorrhage outcomes in the porcine injury model.
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