Method and apparatus to apply pressure and dressing to a cutaneous wound

Abstract

Methods and a device for applying pressure to a skin wound site including a core, a dressing, and an adhesive layer. The core, dressing, and adhesive layer may be layered together and the layering provides positive pressure to a wound site. The adhesive layer may impart positive pressure to the core, dressing, and wound site. The core, dressing, and adhesive may have thicknesses that form a gradient from the wound site to an upper edge of the adhesive layer, a concentration of a chemical is highest at a surface of the dressing, and a rigidity of the device may be formed from a rigidity of the dressing, core, and adhesive layers. Apparatus and methods for applying positive pressure to a skin wound site including combining a core with a dressing surface in contact with the wound site and affixing an adhesive layer to the core, dressing, and a surrounding skin.

Description

[0001] METHOD AND APPARATUS TO APPLY PRESSURE AND DRESSING TO A

[0002] CUTANEOUS WOUND

[0003] Priority Claim

[0004]

[0001] This application claims priority to United States Provisional Patent Application Serial Number 63 / 729,758 filed December 9, 2024 and United States Provisional Patent Application Serial Number 63 / 776,066 filed March 23, 2025. Both applications have the same title, “METHOD AND APPARATUS TO APPLY PRESSURE AND DRESSING TO A WOUND,” and both applications are incorporated by reference in their entirety.

[0005] Field of Invention

[0006]

[0002] Embodiments discussed herein relate to methods and apparatus to apply pressure and dressing to the skin of humans and any mammal.

[0007] Background

[0008]

[0003] Medical care for wound treatment is needed in post-surgical care, after blood draws, and following skin biopsies and cutaneous surgery including full thickness skin grafts. Hemostatis prevents complications such as excessive blood loss or infection. Adhesive dressings or gauze are commonly used to absorb blood and protect wound sites, but these materials do not apply sustained, consistent pressure directly to a wound, particularly in areas where a firm, localized pressure would assist in the hemostatis process. Applying gentle pressure to a bleeding skin surface has historically employed traditional bandages with a continuous cotton ball or other absorbent material depressed on the skin surface and affixed to the skin with medical tape or an adhesive bandage. There are no well-crafted, commercially available products which as a single unit accomplish these goals. Medical practitioners often apply manual pressure with their hands or additional gauze, but, for prolonged periods, applying manual pressure may not be practical. Tight or circumferential wraps can lead to complications of edema or lack of blood flow.

[0009] Manual pressure may be uncomfortable or insufficient over time to control bleeding in some instances. The main problem with commercially available bandages such as Band-Aids™ is that they do not provide positive pressure to adequately stop and prevent continued delayed bleeding after skin biopsies or phlebotomy. Methods and apparatus for controlling the localized, positive pressure applied and for tailoring the material in contact with the skin are needed.

[0010] Summary

[0004] Embodiments herein relate to methods and a device for applying pressure to a skin wound site including a core, a dressing, and an adhesive layer. In some embodiments, the core, dressing, and adhesive layer are layered together and the layering provides positive pressure to a wound site. In some embodiments, the adhesive layer is in contact with human skin and the adhesive layer may impart positive pressure to the core, dressing, and wound site. In some embodiments, the core, dressing, and adhesive have thicknesses that form a gradient from the wound site to an upper edge of the adhesive layer, a concentration of a chemical is highest at a surface of the dressing, and a rigidity of the device may be formed from a rigidity of the dressing, core, and adhesive layers.

[0011]

[0005] Embodiments herein relate to apparatus and methods for applying positive pressure to a skin wound site including combining a core with a dressing surface in contact with the wound site and affixing an adhesive layer to the core, dressing, and a surrounding skin. In some embodiments, the pressure that is applied is controlled by the stiffness of the adhesive layer, by the core’s physical properties, or both. In some embodiments, the core is solid or hollow. In some embodiments, the dressing has a nonstick surface, is absorbent, or both. In some embodiments, affixing includes tailoring a positive pressure based on characteristics of the wound site.

[0012] Figures

[0013]

[0006] Figure l is a sectional view of an embodiment of a device.

[0014]

[0007] Figure 2 is a sectional view of an embodiment of a device engaged with human skin.

[0015]

[0008] Figure 3 is a sectional view of an embodiment of a device with a gradient from the upper surface to a surface for engagement with skin.

[0016]

[0009] Figure 4 is a surface view of an embodiment of a device.

[0017]

[0010] Figure 5 is a surface view of an embodiment of a device with a firm plate.

[0018]

[0011] Figure 6 is a sectional view of an embodiment of a device with a firm plate.

[0019]

[0012] Figures 7A and 7B are a series of views of core cross sections of two embodiments.

[0013] Figures 8A and 8B are a series of views of core cross sections of two embodiments.

[0014] Figure 9 is a dimensional view of a core of an embodiment.

[0020]

[0015] Figure 10 is a dimensional view of a core of an embodiment.

[0021]

[0016] Figure 11 is a sectional view of an embodiment of a device with an adjustable core.

[0017] Figure 12 is a sectional view of an embodiment of a device with an adjustable core. Detailed Description

[0022]

[0018] Embodiments of the invention discussed herein use a firm core embedded in an absorbent wound care dressing and adhesive bandage to apply direct positive pressure to a wound site.

[0023] That is, embodiments of a bolster dressing tailored for applying an intentional positive pressure and surface interaction with the dressing material are described herein. Some embodiments may have a hollow core made of dense solid or semi-solid material embedded in absorbing material that is selected for the surface area of the wound site and the amount of pressure to be applied. Some embodiments may have absorbing material that is selected to have a density, composition, concentration of reagent, or other gradient across the height of the material. A gradient may be selected across the combined layers of material to apply a specific pressure, to provide the device mechanical characteristics such as stability or flexibility or both, or to have a specific concentration of a wound healing enhancing material such as a therapeutic chemical or a material selected for its absorbency.

[0024]

[0019] The positive pressure provided by some embodiments as they are affixed to the skin surrounding a fenestration helps in promoting hemostatis. The bandage may help stabilize the skin and facilitate healing in stabilized skin region. The bandage may be used in both clinical and home care settings. The bandage is easy to apply and does not require additional tools or external pressure from a healthcare provider. The adhesive ensures it stays in place and the core’s design allows for continuous pressure without discomfort. Further, the dressing is as discreet as a typical bandage, but is thicker in the control area. This allows patients to continue normal activities while the wound is protected and pressure is applied.

[0025]

[0020] Wound sites may include minor cuts, skin biopsies, post-blood draw puncture sites, puncture wounds, exudative wounds, traumatic wounds, or any other scenario where localized pressure is beneficial to stop bleeding. Some wound sites may exist after minor procedures, such as blood draws, skin biopsies, surgery, or any other skin procedure where localized pressure is beneficial to control blood flow and promote faster healing.

[0026]

[0021] Some embodiments may be used to apply positive pressure over skin grafts in order to keep the graft in constant contact with the wound bed just below the graft. That is, skin grafts performed on curved surfaces like the ear or nose may have a graft that tents, separates from the wound bed due to hematoma or inversion, and allows for blood or extracellular fluid to pool under the graft which can lead to graft failure or higher risk of infection or other complications. Some embodiments of this device prevent this tenting and pooling.

[0027] [0221 Positive pressure application may be helpful for individuals with clotting disorders or for situations where the wound is not responding adequately to conventional pressure methods.

[0028]

[0023] Some embodiments may also be easy to use and feel comfortable on the skin. The materials for the core, middle layer, and outer layer should also be compatible with the skin, nonirritating, and hypoallergenic to avoid causing skin reactions. The bottom layer, the absorbent layer, includes an absorbent material such as gauze, cotton, or other absorbent fabric. It may be formed of any material designed to wick away blood or other fluid exuding from the wound. This layer helps maintain a clean and dry wound environment and does not stick to the wound bed. In some embodiments, it may be infused with some of many hemostatic agents such as aluminum chloride or nonstick elements coating the gauze or material in contact with the wound bed.

[0029]

[0024] Figure 1 is a schematic that provides a cross-sectional view of the wound care dressing 100 with a core 101, gauze 102, and adhesive layer 103. The dressing 100 may include a solid or semisolid core 101 beneath an absorbent layer 102 to exert sustained positive pressure on a wound. The core lOlmay apply targeted, positive pressure to the wound bed and may be optimized to provide localized, uniform pressure or pressure that is distributed centrally or where a wound is at the greatest risk of bleeding or oozing serosanguinous fluid.

[0030]

[0025] Figure 2 is a schematic view that provides a cross-sectional view of skin 201 with a wound 202 and vessels (capillaries) 203 engaged with a dressing 204 including a core 205 and adhesive 206 and gauze 207 layers as the dressing 204 applies pressure. The gauze 207 may be affixed to the core 205 loosely or may be attached with adhesive. The pressure applied should approximate the pressure needed to stop bleeding, prevent ongoing bleeding, and decrease excess serosanguinous drainage fluid. The bottom layer, the absorptive layer 207, may be treated with nonstick properties such as Vaseline™, Aquaphor™, Tefla™, or other nonstick materials.

[0031]

[0026] Figure 3 is a schematic view that provides a cross -sectional view of a wound care dressing 301 with a core 302 that has a gradient of materials from the exterior surface 303 to the absorbent surface 304 in contact with the skin (not shown). Specifically, the gradient may be layers of material 305 with gradually more and more compressible and more absorbent material and the layers 305 closer to the exterior of the dressing 303 are firmer and less compressible which may also help with engagement with adhesive layer 306. The chemical composition, the density, the weave, the absorbance, the flexibility, and the firmness of the material may be tailored across the gradient formed by layers 302, 303, 304, 305, 306.

[0032]

[0027] Some embodiments may include a graduated, solid, positive pressure adhesive bandage design. The core material in contact with the upper adhesive layer is selected to be made of firmer material in contact with the skin or wound bed surface. This core material farthest from the adhesive layer may be selected for its compressible and absorbent properties as it gets closer and closer to skin. The intermediate layers may be cotton of various compression density or tightness of weave. Thus, the gradient layers, in aggregate, create a surface in contact with the skin that is malleable and delivers positive pressure with some absorbency at the skin surface.

[0028] Figure 4 is a schematic that provides a sectional view of a wound care dressing with a core, nonstick gauze, and adhesive layer. Figure 5 is a schematic, sectional view of a wound care dressing with a convex core affixed to a flat, firm plate for pressure delivery control precision, nonstick gauze, and adhesive layer.

[0033]

[0029] Figure 6 is a schematic, sectional view of the wound care dressing 401 of Figure 5 with the flat, firm plate 503 imparting physical support to the core 502 upon its engagement with the gauze material 504 and skin (not shown). The plate 503 attached to the core 502 may put more pressure on the wound and may be attached to the core 502 or be separate. It may be made of the same material as the core 502 or a different material. The plate 503 may be made of plastic of varied densities or other materials.

[0034]

[0030] The outer layer 506, the adhesive surface, includes a medical-grade, pressure-sensitive adhesive affixed to a flexible fabric, nonwoven layer, plastic sheeting, or other flat film material 503 selected for its rigidity, flexibility, pressure dispersion, or other physical properties that help it accomplish its pressure dispersion, dressing, and mechanical integrity goals. This adhesive layer 506 is selected to ensure the bandage 501 stays in place on the skin in the periphery of the wound site. The material 503 that engages the core and the adhesive may be plastic, rayon, nylon, cotton, or any other man-made or natural fiber, film, or combination thereof.

[0035]

[0031] Figures 7A and 7B are schematic views that compare a hemispherical core 701 to a spherical core 702 with a side view in Figure 7A and views from the top of the core 703, 704 in Figure 7B. Figures 8A and Figure 8B are schematic views that compares a hemispherical core 801 to a half-doughnut core 802 with a side view in Figure 8A and a top view 803, 804 for both in Figure 8B. The core may be selected for its mechanical and chemical properties. Tt may be hollow and soft like one bubble of a bubble wrap system in some embodiments. The core may be solid and rigid for some other embodiments. In some instances, it may include a gel of various consistencies. The core may have a variety of shapes such as an ellipsoid, a half-sphere, a cylinder, irregular, or any other shape that provides consistent, targeted pressure to the wound bed. Some shapes may be tailored for the wound location, size, and site anatomy. Some shapes and materials may be selected for their ability to maintain shape under pressure. For example, a half-spherical shape may be most effective for smaller, localized wounds, while a cylindrical shape may be used for longer or more irregular wounds. That is, the bolster effect of the core may increase the likelihood of clot formation, help control or stop bleeding, or decrease wound exudate in some embodiments. The shape selection may ensure an even and a targeted distribution of pressure over the wound bed.

[0036]

[0032] The core is formed from materials selected for their hardness, rigidity, or firmness to apply pressure in some embodiments. Foam, plastic, rubber, dense cotton, soft plastic with a silicon gel or an air-filled middle, or other material with the appropriate firmness profile may be selected. Foam cores are lightweight and offer moderate compression. Rubber or silicon cores provide more firm and consistent pressure. Cotton or cotton-blend cores may be preferred for softer, more flexible pressure. The material selection may also depend on the desired degree of pressure, comfort, and skin compatibility. The core firmness is tailored to apply constant pressure without discomfort and to conform to the skin and wound area. The core size may vary from 0.5 cm to 3.0 cm or larger.

[0037]

[0033] Figure 9 is a schematic diagram that shows some geometrical considerations for a hemispherical core 901 and its region 902 most likely to be in contact with the gauze in contact with the surface of skin. This convex surface 903 helps form positive pressure as the core and its gauze interact with the fenestration in the surface of the skin.

[0038]

[0034] Figure 10 is a schematic view of a core 1001 that provides geometrical considerations for the surfaces of the hemispherical core and its regions 1002 most likely to be in contact with the adhesive material. This also shows the thickness 1003 of the core wall may be selected to impart rigidity and thus continuous pressure across the surface 1002 of the core 1001.

[0039]

[0035] Some embodiments may have an inflatable pressure design. Such a design may include one or multiple pockets filled with air, other gas, liquid, or gel. Also, two gels or liquids may mix and form a hardened gel that allows greater positive pressure on the wound bed. One or more of the pockets may have a one-way valve to control the gas based pressure within the pocket. Some embodiments may have a central core pocket surrounded by multiple pockets or a central core pocket surrounded by a donut shaped continuous pocket. Any of the pockets may contain a valve. The adhesive layer may provide stability and spacing between the pockets. The adhesive layer may be selected to provide stability and spacing whatever the status of the air, liquid, or gel-filled or evacuated pockets.

[0040]

[0036] Figure 11 is a cross-sectional view of a wound care dressing 1100 in a preactivated state with a central air-filled pressure compression core 1101 with air bladders 1102 on one side or two sides of the central core (or a continuous donut shape). The bladders 1102 may be depressed and air, liquid, or gel flows into the central core 1101 through a one-way valve 1103 or may act as a pump to tailor pressure based individually on the needs of the patient for compression. The absorbent layer 1104 remains in contact with the skin and the adhesive layer 1105 remains on the exterior of the dressing 1100 to provide mechanical support and stability and engage with the healthy surrounding skin (Skin is not shown in Figure 11.).

[0041]

[0037] Figure 12 is a cross-sectional view of a wound care dressing 1200 in an activated state with a central air-filled pressure compression core 1201 that is more expanded and at a higher internal pressure, i.e. more rigid state, for contact with the skin via its absorbent layer 1202. The nearby air chambers 1203 are now at a much lower pressure with less air as their contents have been moved to the central core 1201 via the one-way valves 1204. The adhesive layer 1205 endures to provide mechanical support, stability, and engagement with the surrounding healthy skin (Skin is not shown in Figure 12.).

[0042]

[0038] There are advantages of these bandages. Efficiency for the medical professional includes a premade bandage instead of having to create a custom bandage for each wound. Cleanliness is enhanced, cross-contamination and subsequent skin infection is much less likely when the components of the device are automatically pre-combined. Thus, gloved and ungloved hands are not touching and folding and applying and creating custom bandages for each wound. Lower number of items in inventory are needed, less tape and various gauze sizes when premade bandages are available. Further, inventory control is easier with more precise tracking and knowledge of how many bandages are in inventory. Experimental Results

[0043]

[0039] Approximately 60,000 custom, handmade bandages have been observed and modified. Knowledge from the use of the bandages informed creating additional bandages that were also applied and observed. No custom, premade prototypes or designs were tested on patients with open cutaneous wounds. These custom wound dressings are made and applied to stop and prevent bleeding of cutaneous wounds. These vast majority of these wounds are created by skin biopsies including shave, incisional, and punch type biopsies. The purpose of these biopsies, which are read by pathologists, is to identify various skin conditions including: cancers, autoimmune, infectious diseases, and tumors both benign and malignant.

[0044]

[0040] Some embodiments of bandages include a gauze folded in quarters and placed in the center of adhesive medical tape such as Transpore™. The adhesive is pulled from each end (away from the central folded gauze.) and attached to the skin in such a way that the thickness of the gauze creates positive pressure on the wound bed of the biopsy created ulcer. This pressure is maintained for the duration of the bandage attachment (until manually removed).

[0045]

[0041] Making embodiments of this process into a single product have been successful with several different materials and techniques. Some prototypes use commercially available materials purchased at the pharmacy, craft stores and medical supply stores. The prototypes ranged from relatively simple designs to more complex.

[0046]

[0042] One design was made from Transpore™ tape and multiple layers of cotton gauze to create a thick central absorbent pad capable of compression and absorption.

[0047]

[0043] Another design used the Transpore™ tape with a hard plastic half sphere attached then covered with an absorbent cotton pad. The firmness and convexity of the plastic core created positive pressure on the wound bed.

[0048]

[0044] Another design used a foam core which was compressible covered with an absorbent cotton pad. This allowed for a slightly less rigid feel and lighter weight. This design still maintained positive wound bed pressure.

[0049]

[0045] A bladder design used a hollow soft plastic piece as the core with absorbent gauze on the top. This was the lightest but the least positive pressure of the ones created and tested.

[0050]

[0046] These dressings were initially tested on intact skin of my own arms so that I could feel the pressure applied by each various type. Each of these were more effective at producing positive pressure than any commercially available bandages.

Claims

im:

1. A device for applying pressure to a skin wound site, comprising: a core; a dressing; and an adhesive layer.

2. The device of claim 1, wherein the core, dressing, and adhesive layer are layered together and the layering provides positive pressure to a wound site.

3. The device of claim 1, wherein the adhesive layer is in contact with human skin.

4. The device of claim 3, wherein the adhesive layer imparts positive pressure to the core, dressing, and wound site.

5. The device of claim 1, wherein the core, dressing, and adhesive have thicknesses that form a gradient from the wound site to an upper edge of the adhesive layer.

6. The device of claim 5, wherein a rigidity of the device is formed from a rigidity of the dressing, core, and adhesive layers.

7. The device of claim 1, wherein a concentration of a chemical is highest at a surface of the dressing.

8. A method for applying positive pressure to a skin wound site, comprising: combining a core with a dressing surface in contact with the wound site; and affixing an adhesive layer to the core, dressing, and a surrounding skin.

9. The method of claim 8, where in the pressure that is applied is controlled by the stiffness of the adhesive layer.

10. The method of claim 8, wherein the pressure that is applied is controlled by the core’s physical properties.

11. The method of claim 10, wherein the core is solid.

12. The method of claim 10, wherein the core is hollow.

13. The method of claim 8, wherein the dressing has a nonstick surface.

14. The method of claim 8, wherein the dressing is absorbent.

15. The method of claim 8, wherein the affixing comprises tailoring a positive pressure based on characteristics of the wound site.

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