WO2021048754A1 - Simplified negative pressure absorbent dressing - Google Patents

Abstract

A wound dressing includes a perforated silicone layer, a first wicking layer, a superabsorbent layer, a hydrophobic foam layer, a second wicking layer, and a drape layer, all having a first and a second side, the second sides facing the wound bed. The border of the first side of the first wicking layer is adhered to the second side of the second wicking layer, forming an adhesive border surrounding the superabsorbent layer and the hydrophobic foam layer such that the superabsorbent layer and the hydrophobic foam layer are free-floating between the first wicking layer and the second wicking layer. Finally, the hydrophobic foam layer is configured to repel fluid to assist with fluid manifolding throughout the wound dressing.

Description

SIMPLIFIED NEGATIVE PRESSURE ABSORBENT DRESSING

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Provisional Application No.

62/898,908, filed on September 11, 2019, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] The present invention relates generally to the field of wound therapy, and more in particular to dressings for use in negative pressure wound therapy.

[0002] Negative pressure wound therapy (NPWT) is a type of wound therapy that involves in applying negative pressure (relative to atmospheric pressure) to a wound bed to promote wound healing. Typically, a wound dressing is sealed over a wound bed and air is pumped out of the dressing to create a negative pressure at the wound bed. In some NPWT systems, wound exudate and other fluid is pumped out of the dressing and collected by a therapy system. In other NPWT systems, air is pumped out of the dressing while the dressing is used to absorb fluid from the wound. In some such systems, it is preferable for air to be drawn to the pump while fluid or other wound exudate is prevented from reaching the pump, such that the pump is protected from contamination or other damage that may be caused by such fluid or other exudate contacting the pump. Accordingly, assemblies for protecting the pump from contact with fluid or other wound exudate while also allowing the pump to remove air from the dressing are needed.

[0003] To facilitate the establishment of negative pressure, the dressing may include a plurality of layers, and more particularly may include a silicone adhesive that is suitable for creating a substantially-airtight seal between the dressing and the patient’s skin. However, dressings used in traditional NPWT are often costly. It would be desirable to provide a wound dressing for use in NPWT that is low cost while maintaining the dressing’s ability to manifold pressures, fluids, and liquids. SUMMARY

[0004] One implementation of the present disclosure is a wound dressing including a perforated silicone layer, a first wicking layer, a superabsorbent layer, a hydrophobic foam layer, a second wicking layer, and a drape layer. The perforated silicone layer is configured to engage a wound bed, and has a first side and a second side, the second side configured to face the wound bed. The first wicking layer has a first side and a second side, the second side configured to face the first side of the perforated silicone layer. The super absorbent layer has a first side and a second side, the second side configured to face the first side of the first wicking layer. The hydrophobic foam layer has a first side and a second side, the second side configured to face the first side of the superabsorbent layer. The second wicking layer has a first side and a second side, the second side configured to face the first side of the hydrophobic foam layer. The drape layer has a first side and a second side, the second side configured to face the first side of the second wicking layer. The border of the first side of the first wicking layer is adhered to the second side of the second wicking layer, forming an adhesive border surrounding the superabsorbent layer and the hydrophobic foam layer such that the superabsorbent layer and the hydrophobic foam layer are free-floating between the first wicking layer and the second wicking layer. Finally, the hydrophobic foam layer is configured to repel fluid to assist with fluid manifolding throughout the wound dressing.

[0005] Another implementation of the present disclosure is a wound therapy system including a pump, a tube coupled to the pump, a negative pressure interface assembly, and a wound dressing coupled to the tube via the assembly. The wound dressing includes a perforated silicone layer, a first wicking layer, a superabsorbent layer, a hydrophobic foam layer, a second wicking layer, and a drape layer. The perforated silicone layer is configured to engage a wound bed, and has a first side and a second side, the second side configured to face the wound bed. The first wicking layer has a first side and a second side, the second side configured to face the first side of the perforated silicone layer. The super absorbent layer has a first side and a second side, the second side configured to face the first side of the first wicking layer. The hydrophobic foam layer has a first side and a second side, the second side configured to face the first side of the superabsorbent layer. The second wicking layer has a first side and a second side, the second side configured to face the first side of the hydrophobic foam layer. The drape layer has a first side and a second side, the second side configured to face the first side of the second wicking layer.

[0006] Another implementation of the present disclosure is a method of applying a wound dressing. The method comprises exposing a perforated silicone layer of the wound dressing by removing a first release liner from the dressing, the perforated silicone layer forming a portion of a central region of the wound dressing. The method further comprises aligning the central region of the dressing with a wound bed of a patient. The method further comprises sealing the perforated silicone layer to the patient around the wound bed. The method further comprise operating a pump coupled to the central region of the dressing to verify that a seal is established between the perforated silicone layer and the patient. The method further comprises exposing an acrylic adhesive border of the dressing in the form of a drape layer by removing a second release liner from the dressing, the acrylic adhesive border at least partially surrounding the perforated silicone layer. Finally, the method comprises adhering the acrylic adhesive border to the patient.

[0007] Another implementation of the present disclosure is a system for treating a tissue site. The system includes a dressing and a negative pressure source. The dressing includes an interface layer in contact with the tissue site. The dressing further includes a dressing core configured to be in fluid communication with the tissue site through the interface layer, the dressing core including a superabsorbent layer disposed between a first wicking layer and a second wicking layer, and a manifold disposed between the superabsorbent layer and the first wicking layer. The dressing further includes a drape disposed over the interface layer and the dressing core. Finally, the negative pressure source is configured to be in fluid communication with the tissue site through the drape.

[0008] Another implementation of the present disclosure is a wound dressing. The wound dressing includes a patient interface layer having a plurality of perforations, the patient interface layer configured to engage a wound bed, a first wicking layer atop the patient interface layer, a superabsorbent layer atop the first wicking layer, a manifold layer atop the first wicking layer, a second wicking layer atop the manifold layer, a first drape layer atop the manifold layer; and a second drape layer atop the first drape layer. A border of the second drape layer extends beyond a border of the first drape layer and is coated with an acrylic adhesive configured to adhere the wound dressing to a skin of a patient. Finally, the first wicking layer is adhered to a border of the second wicking layer, forming an adhesive border surrounding the superabsorbent layer and the manifold layer such that the superabsorbent layer and the manifold layer are free-floating between the first wicking layer and the second wicking layer, and wherein the manifold layer is configured to repel fluid to assist with fluid manifolding throughout the wound dressing.

[0010] Those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the devices and/or processes described herein, as defined solely by the claims, will become apparent in the detailed description set forth herein and taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 is a top view of a wound dressing, according to an exemplary embodiment.

[0012] FIG. 2 is a bottom view of the wound dressing of FIG. 1, according to an exemplary embodiment.

[0013] FIG. 3 is an exploded perspective view illustrating several layers of the wound dressing of FIGS. 1 and 2, according to an exemplary embodiment.

[0014] FIG. 4 is an exploded perspective view illustrating several layers of the wound dressing of FIGS. 1 and 2, according to an exemplary embodiment.

[0009] FIG. 5 is an exploded cross-section view illustrating several layers of the wound dressing of FIGS. 1 and 2, according to another exemplary embodiment. [0010] FIG. 6 is a perspective view of the wound dressing of FIGS. 1 and 2 adhered to a patient, according to an exemplary embodiment.

[0011] FIG. 7 is a graph illustrating the absorption capacities of wound dressings, according to an exemplary embodiment.

[0018] FIG. 8 is a graph illustrating the absorption capacities of wound dressing, according to an exemplary embodiment.

DETAILED DESCRIPTION

[0019] Referring now to FIGS. 1-8, an absorbent wound dressing for use with a negative pressure wound therapy (NPWT) system is shown, according to exemplary embodiments. The wound dressing of the exemplary embodiments has multiple layers, including a patient interface layer, a plurality of non-woven layers, an absorbent layer, a foam layer, and a drape layer, as well as a connection assembly configured to pneumatically couple the wound dressing to a pump of the NPWT system. The wound dressing may be pneumatically coupled to the pump such that air can be transferred between the two. In other embodiments, the wound dressing may be fluidly communicable with the pump via a tube such that liquid, wound exudate, etc., in addition to air can be moved out of the wound dressing into the NPWT system. In some embodiments, the wound dressing has a plurality of release liners configured to be removed throughout the process of applying the wound dressing to an application site (e.g., a wound bed). In some embodiments, the patient interface layer has a plurality of perforations in order to increase fluid uptake of the wound dressing. In some embodiments, the connection assembly has a filter and an indicator, configured to provide an indication of when the wound dressing has reached an absorption capacity and fluid has passed through the filter. In still other embodiments, other configurations and layers of the wound dressing are possible. [0020] Advantageously the wound dressing allows a negative pressure to be maintained at the wound bed while absorbing fluid from the wound bed. The layers of the dressing are intended to provide for maximum fluid uptake into the dressing, as fluid is drawn upwards through the dressing via the negative pressure gradient. A connection assembly, which connects the dressing to the pump, has therein an indicator, which provides an indication as to when the dressing has reached a maximum fluid capacity. Once the dressing has reached a maximum fluid capacity, the dressing can be removed and discarded, providing a lower-cost alternative to traditional NPWT dressings.

Wound Dressing

[0021] Referring now to FIGS. 1-8, a negative pressure wound therapy (NPWT) system 100 and a wound dressing 102 for use therewith are shown, according to an exemplary embodiment. The NPWT system 100 includes tubing 104 for coupling wound dressing 102 to a pump (not shown). In a brief overview, FIG.1 is a top view of wound dressing 102, as would be visible when wound dressing 102 is adhered to a surface (e.g., a patient’s skin). FIG. 2 is a bottom view of wound dressing 102 showing the surface of wound dressing 102 configured to contact a wound bed and the surrounding skin. FIG. 3 is an exploded perspective view of the dressing of FIG. 1, illustrating components and layers 108-116 of wound dressing 102. FIG. 4 is another exploded perspective view of the dressing of FIG. 1, according to another embodiment. FIG. 5 is an exploded cross-sectional view of wound dressing 102. FIG. 6 is a perspective view of wound dressing 102 adhered to a wound bed on a patient’s arm. FIGS. 7-8 are graphical representations illustrating the absorption capacity of wound dressing 102 when constructed with and without a foam layer. The various views show various features of wound dressing 102 and are described concurrently in the following.

[0022] In various embodiments, wound dressing 102 can be formed as a substantially flat sheet for topical application to wounds, or formed as a contoured dressing for application to body surfaces having high curvature. The size and shape of wound dressing 102 can vary depending on the size of the wound to be dressed and its location. For example, it is contemplated that the size of wound dressing 102 can range from approximately 1 cm² to 200 cm², and more preferably from approximately 4 cm² to 100 cm². However, other shapes and sizes of wound dressing 102 are also possible depending on the intended use. In other embodiments, wound dressing 102 may have a substantially convex or concave shape, or other customizable topography to adhere to wounds located on areas such as the knee or elbow.

[0023] Wound dressing 102 is shown to include (among other possible layers), a drape layer 108, a first wicking layer 110, a hydrophobic foam layer 112, a superabsorbent layer 114, a second wicking layer 116, and a perforated silicone layer 118. In some embodiments, wound dressing 102 further includes a silicone release liner 120 and an acrylic release liner 122, configured to be removed during application of the wound dressing 102 to a wound bed. In some embodiments, the first wicking layer 110 and the second wicking layer 116 are adhered together around the periphery, forming an adhesive border surrounding the superabsorbent layer 114 and the hydrophobic foam layer 112 such that the superabsorbent layer 114 and the hydrophobic foam layer 112 are free-floating between the first wicking layer 110 and the second wicking layer 116. In some embodiments, the drape layer 108 is even with a perimeter of the perforated silicone layer 118. In other embodiments, the drape layer 108 may extend past the perimeter of the perforated silicone layer 118, such that the drape layer 108 extends past the other layers of wound dressing 102. In some embodiments, wound dressing 102 further includes a second drape layer 164 that extends past the perimeter of drape layer 108. However, other configurations and locations of the layers are also possible depending on the intended use.

Drape Layer

[0024] In some embodiments, wound dressing 102 includes a drape layer 108. Drape layer 108 is shown to include a first side 124 and a second side 126 opposite first side 124. Second side 126 is configured to face a wound. When wound dressing 102 is applied to a wound, first side 124 faces away from the wound whereas second side 126 faces toward the wound. Drape layer 108 attaches over first wicking layer 110, hydrophobic foam layer 112, superabsorbent layer 114, second wicking layer 116, and perforated silicone layer 118. In some embodiments, drape layer 108 is laminated/bonded via fusible fiber to one or more of first wicking layer 110 and second wicking layer 116. In some embodiments, drape layer 108 is also laminated to perforated silicone layer 118 around only a perimeter of the second side 126 of drape layer 108. In some embodiments, the perimeter of drape layer 108 extends beyond (e.g., circumscribes) the perimeter of perforated silicone layer 118 to provide a margin for wound dressing 102 (e.g., as an “island” dressing) to adhere to the skin of a patient adjacent to the wound being treated. In some embodiments, drape layer 108 may extend beyond perforated silicone layer 118 by between 10 mm and 20 mm. In still other embodiments, the perimeter of drape layer 108 is even with the perimeter of perforated silicone layer 118.

[0025] In some embodiments, drape layer 108 is a thin layer of polyurethane film. One example of a suitable material for drape layer 108 is the polyurethane film known as ESTANE 5714F. Other suitable polymers for forming drape layer 108 include poly alkoxylalkyl acrylates and methacrylates, such as those described in Great Britain Patent Application No. 1280631 A filed November 22, 2002, the entire disclosure of which is incorporated by reference herein. In some embodiments, drape layer 108 includes a continuous layer of a high-density blocked polyurethane foam that is predominantly closed-cell. Drape layer 108 may have a thickness in the range of 10 pm to 100 pm, preferably in the range of 50 pm to 70 pm. In some embodiments, drape layer 108 has a thickness of approximately 60 pm. Drape layer 108 may be substantially permeable to liquid and moisture vapor. In other words, drape layer 108 may be permeable to both water vapor and liquid water such as wound exudate. Such permeability is intended to facilitate or enhance a hydrophilic gradient from the wound bed, through the wound dressing 102, and to the surrounding atmosphere. In some embodiments, drape layer 108 is impermeable to bacteria and other microorganisms. In some embodiments, drape layer 108 may be substantially hydrophilic and have a high MVTR, such as to permit evaporation of wound exudate/fluid from first side 124. In an alternative embodiment, drape layer 108 may be coated with a layer of charcoal, configured to reduce odor from the wound dressing 102. In still other embodiments, drape layer 108 may comprise a layer of a non-woven material coated with charcoal or a large piece of woven charcoal cloth. Still other configurations and materials of drape layer 108 are possible.

[0026] In some embodiments, the entire second side 124 of drape layer 108 may be coated with an adhesive, either in a continuous coat or as a pattern coated adhesive. The adhesive may comprise an acrylic adhesive or any other suitable type of adhesive. In other embodiments, the second side 124 of drape layer 108 may be coated with an adhesive solely on the perimeter of the second side 124, such that a central portion of second side 124 is free of adhesive. The adhesive- coated perimeter of second side 124 may provide a sealed border or a bond between the drape layer 108 and the perforated silicone layer 118. Thus, the sealed border of the drape layer 108 and the perforated silicone layer 118 surrounds the first wicking layer 110, the hydrophobic foam layer 112, the superabsorbent layer 114, and the second wicking layer 116. When the drape layer 108 extends past the perforated silicone layer 118, the adhesive-coated perimeter of second side 124 provides a seal between the wound dressing 102 and the application site, e.g. the patient’s skin.

[0027] In some embodiment, wound dressing 102 may comprise a plurality of drape layers 108 and 162, such as in the embodiment shown in FIG. 4. The drape layer 108 may be applied directly over first wicking layer 110, as described above, and may be coextensive with first wicking layer 110. A second drape layer 162 may then be applied over drape layer 108, such that a second side 166 of drape layer 162 contacts the first side 124 of drape layer 108. Drape layer 162 may be comprised of substantially the same materials as drape layer 108, such that drape layer 162 is a thin layer of polyurethane film. Drape layer 162 may be substantially ring-shaped or “picture frame” shaped, such that there is a central opening. Thus, when drape layer 162 is placed over drape layer 108, a central portion of drape layer 108 remains exposed. A perimeter of drape layer 162 may be configured to extend past a perimeter of drape layer 108. In some embodiments, drape layer 162 may extend past a perimeter of drape layer 108 by between 10 mm and 20 mm. Drape layer 162 may comprise an acrylic release liner on the second side 166, while drape layer 108 may be void of acrylic release liner 122. In some embodiments, drape layer 108 may be substantially free of adhesive, such as to form a non-adhesive drape layer. The second side 166 of drape layer 162 may comprise an acrylic adhesive around the border, such that drape layer 162 adheres wound dressing 102 to a wound bed. In still other embodiments, wound dressing 102 is void of drape layer 162, and drape layer 108 comprises an adhesive. Still other configurations and layers of the drape layer 108 are also possible.

[0028] In the embodiments shown, second side 126 of drape layer 108 is covered with an acrylic release liner 122. Acrylic release liner 122 may be removably coupled to second side 126 of drape layer 108 to cover the adhesive prior to application of wound dressing 102. In some embodiments, acrylic release liner 122 extends only around a perimeter of second side 126 of drape layer 108, such that acrylic release liner 122 only covers the portion of second side 126 which will be adhered to the application site. In some embodiments, acrylic release liner 122 is not removed from drape layer 108 until after perforated silicone layer 118 is applied to the application site. After application of perforated silicone layer 118, acrylic release liner 122 may be removed from the second side 126 to expose the adhesive-coated perimeter of second side 126 of drape layer 108 that extends beyond the perforated silicone layer 118. The adhesive-coated perimeter of drape layer 108 may then be applied to the application site surrounding the wound bed, in order to provide a further seal of wound dressing 102 to the application site. Further detail of the application process of wound dressing 102 are provided below in reference to the perforated silicone layer 118.

[0029] Drape layer 108 is shown to have an opening 160, wherein the connection assembly 106 is configured to attach to the wound dressing 102 via opening 160. In some embodiments, opening 160 is a cut-out of drape layer 108, and extends entirely from first side 124 to second side 126 of drape layer 108. Opening 160 may have a diameter of between 0.3 mm and 1.2 mm, though in other embodiments other diameter holes are possible. The connection assembly 106 is configured to couple the wound dressing 102 to tubing 104, which is coupled to a pump (not shown). The connection assembly 106 is configured to allow airflow between first wicking layer 110 and the pump via opening 160 in drape layer 108, while restricting the flow of fluid therethrough. For example, the connection assembly 108 may further include a filter or membrane that allows airflow therethrough while preventing the flow of fluid therethrough, which are described in further detail below.

Wicking Layers

[0030] In some embodiments, wound dressing 102 includes a first wicking layer 110 and a second wicking layer 116. First wicking layer 110 is shown to include a first side 128 and a second side 130 opposite the first side 128. When wound dressing 102 is applied to a wound, first side 128 faces away from the wound towards second side 126 of drape layer 108 whereas second side 130 faces towards the wound and towards a first side 132 of hydrophobic foam layer 112. Second wicking layer 116 is also shown to include a first side 140 and a second side 142. When wound dressing 102 is applied to a wound, first side 140 faces away from the wound towards a second side 138 of superabsorbent layer 114 whereas second side faces towards the wound and towards a first side 144 of perforated silicone layer 118. In some embodiments, wicking layers 110, 116 are configured to wick wound exudate and other fluids from the wound bed towards superabsorbent layer 114, and to maintain the location of fluids within superabsorbent layer 114. First wicking layer 110, which is directly underneath the drape layer 108, is configured to prevent wound exudate and other fluids from releasing from within superabsorbent layer 114 and being sucked into tubing 104 as the system 100 creates a negative pressure gradient within wound dressing 102. Wicking layers 110, 116 aid in transferring fluids into superabsorbent layer 114 in order to manage perspiration within wound dressing 102. In some embodiments, wicking layers 110, 116 comprise a thin layer of a non-woven material. The non-woven material may be 100% polyethylene or polyethylene terephthalate, such as Sawabond® 4383/4157. In some embodiments, second wicking layer 116 may be coated with OxySalts in an appropriate concentration in order to protect wound dressing 102 from bacterial colonization. In other embodiments, second wicking layer 116 may be pattern printed with iodine in order to utilize iodine out-gassing to act as an anti-microbial to prevent bacteria from entering the inner layers of wound dressing 102. In still other embodiments, wicking layers 110, 116 comprise a high wicking material, such as Milliken Interdry or Libeltex TDL2. In still other embodiments, other configurations and materials for wicking layers 110, 116 are possible.

[0031] In some embodiments, a perimeter of second side 130 of first wicking layer 110 may be laminated or otherwise adhered to a perimeter of first side 140 of second wicking layer 116, such as shown in FIG. 2. The perimeters of wicking layers 110, 116 extend past the perimeters of hydrophobic foam layer 112 and superabsorbent layer 114, such that adhesion of the perimeters of wicking layers 110, 116 provides an adhesive border surrounding hydrophobic foam layer 112 and superabsorbent layer 114. The adhesion of the perimeters of wicking layers 110, 116 not only aids in wicking fluids into superabsorbent layer 114, but also prevents the release of fluids from superabsorbent layer 114 when wound dressing 102 is subject to negative pressure. Most notably, first wicking layer 110 prevents fluid from escaping superabsorbent layer 114 and traveling upwards throughout wound dressing 102, such that wound dressing 102 is able to absorb a maximum amount of fluid before requiring the dressing 102 to be changed. In some embodiments, first side 128 of first wicking layer 110 is adhered to second side 126 of drape layer 108 via a fusible fiber. In some embodiments, a perimeter of first side 140 of second wicking layer 142 may also be adhered to second side 126 of drape layer 108 via a fusible fiber. The adhesion of wicking layers 110, 116 to drape layer 108 creates a central chamber of wicking material within wound dressing 102, such that hydrophobic foam layer 112 and superabsorbent layer 114 are entirely surrounded/encapsulated by the wicking material.

[0032] Second wicking layer 116 may directly contact the wound bed through the perforations 148 within perforated silicone layer 118. When second wicking layer 116 contacts the wound bed through the perforations 148, second wicking layer 116 rapidly increases the uptake of wound exudate from the wound bed. Once fluids, including wound exudate or perspiration, have entered into second wicking layer 116, second wicking layer 116 is configured to transfer the fluids towards superabsorbent layer 114, where they are then contained. Second wicking layer 116 is intended to promote the transfer of fluids from the wound bed towards the superabsorbent layer 114. First wicking layer 110 is intended to aid in retaining fluids within superabsorbent layer 114 in order to maximum fluid handling capacity within wound dressing 102. By surrounding superabsorbent layer 114 with wicking layers 110, 116 fluid is consistently wicked inwards towards superabsorbent layer 114. When a negative pressure gradient is established throughout wound dressing 102, fluid will naturally be pulled upwards throughout the dressing 102 and towards the connection assembly 106. First wicking layer 110 is intended to prevent this uptake of fluid into connection assembly 106 by promoting the retainment of fluid within superabsorbent layer 114.

Hydrophobic Foam Layer

[0033] In some embodiments, wound dressing 102 includes a hydrophobic foam layer 112. Hydrophobic foam layer 112 is shown to include a first side 132 and a second side 134. When wound dressing 102 is applied to a wound, first side 132 faces away from the wound towards second side 130 of first wicking layer 110, whereas second side 134 faces towards the wound and towards a first side 136 of superabsorbent layer 114. In some embodiments, the hydrophobic foam layer 112 is intended to manifold pressure over the area of the superabsorbent layer 114 when a negative pressure gradient is established throughout wound dressing 102 and also to aid in repelling fluids which may be drawn upwards from the superabsorbent layer 114 due to the pressure gradient. The hydrophobicity of hydrophobic foam layer 112 prevents fluid from traveling upwards throughout the wound dressing from the superabsorbent layer 114, through hydrophobic foam layer 112, and towards first wicking layer 110. Rather, the hydrophobicity aids in retaining fluids within superabsorbent layer 114. The hydrophobic foam layer 112 helps retain fluids within superabsorbent layer 114 in order to maximize fluid absorption of wound dressing 102 and to prevent the uptake of any fluids into tubing 104, which can cause damage to the pump as there is typically no fluid collection canister in use with the system 100.

[0034] In some embodiments, hydrophobic foam layer 112 is not adhered to either of first wicking layer 110 nor superabsorbent layer 114, such that hydrophobic foam layer 112 is substantially “free-floating”. The adhesion of the perimeters of first wicking layer 110 and second wicking layer 116 creates a “chamber” within the wound dressing 102, such that hydrophobic foam layer 112 and superabsorbent layer 114 are surrounded by a wicking material.

[0035] Hydrophobic foam layer 112 is configured to allow airflow therethrough, in order to establish the negative pressure and to facilitate the distribution of negative pressure across the wound bed. In some embodiments, the hydrophobic foam layer 112 includes an open-celled foam, for example a foam material marketed as GRANUFOAM™by ACELITY™ In other embodiment, hydrophobic foam layer 112 includes any substantially hydrophobic, open-celled foam. In some embodiments, hydrophobic foam layer 116 may be coated with OxySalts in an appropriate concentration in order to protect wound dressing 102 from bacterial colonization. Hydrophobic foam layer 112 may be configured to retain a ‘spring’, such that wound dressing 102 is perceived as soft and comfortable to a patient. In some embodiments, hydrophobic foam layer 112 may have a thickness within a range between approximately 2mm and 6mm.

[0036] In some embodiments, hydrophobic foam layer 112 may be felted in order to reduce the overall thickness of wound dressing 102. The open-cell foam may be heated and compressed (i.e., felted) to approximately one-fifth of an original thickness (i.e., approximately 5-times felted) in order to create the material used for a felted hydrophobic foam layer 112. In other embodiments, various other degrees of felting may be used, for example in a range between approximately 3-times felted and approximately 10-times felted. The felted foam of hydrophobic foam layer 112 is denser than the original open-cell foam while preserving the open-cell structure such that air can flow through the felted foam. After felting, the pores size of the felted foam may be in a range between approximately 90 pores per inch to about 360 pores per inch, depending on the degree of felting. According to an embodiment, an open-cell foam with a firmness of 3 with an original (uncompressed) pore size of 45ppi, will have a felted pore size of 3x45 (135ppi). During the felting process, the pores may be substantially flattened away from the original spherical/polyhedral forms. In some embodiments, hydrophobic foam layer 112 is constructed from a material having a natural (e.g., off-white or yellow) color, such that it is not mistaken for other commonly used foam materials in other dressings. In still other embodiments, other configurations and materials of hydrophobic foam layer 112 are possible. Superabsorbent Layer

[0037] In some embodiments, wound dressing 102 includes a superabsorbent layer 114. Superabsorbent layer 114 is shown to include a first side 136 and a second side 138. When wound dressing 102 is applied to a wound, first side 136 faces away from the wound whereas second side 138 faces towards the wound. In some embodiments, first side 136 of superabsorbent layer 114 contacts second side 134 of hydrophobic foam layer 112 while second side 138 of superabsorbent layer 114 contacts a first side 140 of second wicking layer 116. In some embodiments, superabsorbent layer 114 is configured to wick moisture from second wicking layer 116 and distribute the moisture across first side 136. Superabsorbent layer 114 also draws wound exudate from the wound bed up through the perforations 148 in the patient interface layer 118 and directly up through the second wicking layer 116 towards the superabsorbent layer 114

[0038] In some embodiments, superabsorbent layer 114 may comprise a superabsorbent polymer (SAP) material. The SAP is constructed of a superabsorbent powder, an acetate and ethylene copolymer, and a fiber material. In some embodiments, the superabsorbent powder is a sodium polyacrylate, such as Favor®-PAC320. In some embodiments, the acetate is a glue vinyl acetate, and the acetate and ethylene copolymer may be Pafra 8667. In some embodiments, the fiber material is a 65% viscose and 35% polyethylene terephthalate (PET) spunlace, such as LIDRO 50g/m². In still other embodiments, the SAP may be constructed of other materials. The SAP may be in the form of granules that are contained in a water soluble carrier polymer. One example of the water soluble carrier polymer is polyvinylpyrrolidone (PVP). In some embodiments, superabsorbent layer 114 may be in the form of a superabsorbent particulate or powder material. The particulate may be placed centrally between hydrophobic foam layer 112 and second wicking layer 116, such that the particulate is encapsulated within hydrophobic foam layer 112 and second wicking layer 116. In some embodiments, the superabsorbent layer 114 comprises a slightly porous material while simultaneously having a high SAP density. Advantageously, superabsorbent layer 114 may provide enhanced absorbency for liquid uptake. This is because the porous structure of the foam provides for rapid uptake of liquid exudate. In some embodiment, superabsorbent layer 114 may allow for the evaporation of liquid exudate through the high MVTR drape layer 102.

[0039] In some embodiments, the perimeters of the drape layer 108, first and second wicking layers 110, 116, and perforated silicone layer 118 extend beyond the perimeter of superabsorbent layer 114, such that superabsorbent layer 114 and hydrophobic foam layer 112 are smaller than the rest of the layers. In some of the embodiments, the perimeter of superabsorbent layer 114 is inset from, e.g., non-coextensive with, the border region of the drape layer 108 and the perforated silicone layer 118, which may be adhered together around the perimeter forming a border surrounding superabsorbent layer 114. In some embodiments, first wicking layer 110 and second wicking layer 116 may be adhered to second side 126 of drape layer 108 and/or to each other around the perimeter. In these embodiments, superabsorbent layer 114 (along with hydrophobic foam layer 112) is thus “free-floating” between the plurality of other layers within wound dressing 102. Superabsorbent layer 114 is configured to retain wound exudate and other fluids that have been absorbed from the wound bed and to prevent any fluids from leaking from wound dressing 102. In some embodiments, superabsorbent layer 114 is surrounding by wicking material, such as wicking layers 110, 116, which helps maintain fluid within superabsorbent layer 114.

Perforated Silicone Layer

[0040] In some embodiments, wound dressing 102 includes a patient interface layer shown as a perforated silicone layer 118. Perforated silicone layer 118 is shown to include a first side 144 and a second side 146 opposite first side 144. Second side 146 is configured to contact a wound bed. In some embodiments perforated silicone layer 118 may lie entirely within the confines of a wound bed. In other embodiments, perforated silicone layer 118 may be configured to overlie a periwound region that surrounds the wound bed. Perforated silicone layer 118 may be configured to provide a low to moderate tack adhesive in order to anchor wound dressing 102 to the application site, e.g. a wound bed and the surrounding skin. This low to moderate tack adhesive maintains a fluid seal between perforated silicone layer 118 and the wound bed while refraining from causing damage or discomfort to the patient. In some embodiments, perforated silicone layer 118 may form a continual adhesive border surrounding the wound bed in order to ensure a perimeter seal once the wound dressing 102 is applied. In some embodiments, second side 146 of perforated silicone layer 118 may be covered with a silicone release liner 120. Silicone release liner 120 may be removably coupled to second side 146 to cover the adhesive prior to application of wound dressing 102. When wound dressing 102 is to be applied, silicone release liner 120 is removed from second side 146 in order to reveal the adhesive of perforated silicone layer 118 such that wound dressing 102 can be adhered to the application site. In some embodiments, silicone release liner 120 is in the form of a single sheet of material covering the entirety of second side 146, such that silicone release liner 120 is released from perforated silicone layer 118 in a single piece. In other embodiments, silicone release liner 120 comprises a plurality of sections, such that silicone release liner 120 is released from perforated silicone layer 118 in two or four sections.

[0041] In some embodiments, a perimeter of first side 144 of perforated silicone layer 118 may be laminated or otherwise adhered to second side 126 of drape layer 108. Second side 126 of drape layer 108 may comprise a high tack adhesive in order to adhere to first side 144 of perforated silicone layer 118. The high tack adhesive on a perimeter of second side 126 of drape layer 108 may contact the patient’s skin through perforations 148 within the perforated silicone layer 118. Thus, the high tack adhesive further anchors the wound dressing 102 to the patient. The adhesion of drape layer 108 to perforated silicone layer 118 further provides an adhesive border surrounding the plurality of other layers. In some embodiments, the perimeter of perforated silicone layer 118 is even with the perimeter of drape layer 108. In other embodiments, the perimeter of drape layer 108 extends beyond the perimeter of perforated silicone layer 118.

[0042] In some embodiments, perforated silicone layer 118 may comprise a plurality of perforations 148. Such perforations 148 may increase flexibility of wound dressing 102 and increase the uptake of wound exudate through perforated silicone layer 118 and towards second wicking layer 116. In some embodiments, perforations may be evenly distributed on the entirety of perforated silicone layer 118, such as shown in FIG. 3. In other embodiments, perforations may extend around only a portion of perforated silicone layer 118, or may be distributed in a non-uniform fashion. In some embodiments, perforations 148 may extend through only a portion of perforated silicone layer 118. In other embodiments, perforations 148 may extend entirely from first side 144 to second side 146 of perforated silicone layer 118, such that they form small openings through the perforated silicone layer. Perforations 148 are intended to allow second wicking layer 116 to directly contact the wound bed and/or surrounding skin through the patient perforated silicone layer 118, in order to promote the uptake of wound exudate and perspiration into second wicking layer 116 and towards superabsorbent layer 114.

[0043] A method of application of wound dressing 102 will now be described, according to an exemplary embodiment. Prior to application of wound dressing 102 to a patient 158, silicone release liner 120 must be removed from the second side 146 of perforated silicone layer 118. Once the wound bed is located on the patient 158, a caregiver can remove silicone release liner 120 in order to expose Silicone release liner 120 may be removed as a single sheet, or in some cases may be removed in two or four sections in order to expose the entirety of perforated silicone layer 118. After removal of silicone release liner 120, wound dressing 102 can be aligned with a wound bed of the patient 158. Then, the perforated silicone layer 118 can be sealed to the patient 158 around the wound bed, in order to keep wound dressing 102 in place. The low to moderate tack of the adhesive of perforated silicone layer 118 adheres the wound dressing 102 to the patient 158 throughout the rest of the application process. Connection assembly 106 may be connected to wound dressing 102, as described below, in order to connect wound dressing 102 to a pump. The pump is then operated to verify that a seal has been established between the perforated silicone layer 118 and the patient 158.

In some embodiments, after verifying the seal on the perforated silicone layer 118, the acrylic release liner 122 may be removed from the second side 126 of drape layer 108, thus exposing an acrylic adhesive border of wound dressing 102 in the form of drape layer 108. Acrylic release liner 122 may be removed as a single sheet, or in some cases may be removed in two or four sections. Acrylic release liner 122 may only cover a perimeter of second side 126 of drape layer 108. After a user is satisfied with the placement of the perforated silicon layer 118 (and relying solely on the tack of the silicone adhesive), the perimeter of drape layer 108 may be adhered to an area surrounding the wound bed, in order to establish another seal between wound dressing 102 and the patient 158. The acrylic adhesive border of the drape layer 108 is pressed down to directly contact the patient 158 through perforations 148 in perforated silicone layer 118, achieving high tack bonds between the drape layer 108 and the patient 158. Pressing down the acrylic adhesive on drape layer 108 through perforated silicone layer 118 thus provides a substantial adhesion to the patient 158, making wound dressing 102 more difficult to remove. Once wound dressing 102 is applied, wound dressing 102 may be used in conjunction with the system 100 in order to establish a negative pressure gradient within wound dressing 102.

[0044] In some other embodiments, a wound dressing 102 in which drape layer 108 is coextensive with the first wicking layer 110 may be used. In such an embodiment, drape layer 108 may be void of an acrylic release liner 122 and wound dressing 102 may instead contain the additional drape layer 162, which forms a border surrounding the wound dressing 102. After sealing the perforated silicone layer 118 to the patient 158, an acrylic release liner on the second side 166 of drape layer 162 is removed. The removal of the liner releases the acrylic adhesive on a perimeter of drape layer 162. Drape layer 162 may then be pressed down on top of wound dressing 102, such that a perimeter of drape layer 162 extends past and surrounds a perimeter of drape layer 108. The perimeter of second side of drape layer 162 is then adhered to the area surrounding the wound bed in order to establish another seal between wound dressing 102 and the patient 158. The acrylic adhesive border of the drape layer 162 is then pressed down to directly contact the patient 158 through perforations 148 in perforated silicone layer 118, achieving high tack bonds between the drape layer 162 and the patient 158. Pressing down the acrylic adhesive on drape layer 162 through perforated silicone layer 118 thus provides a substantial adhesion to the patient 158, making wound dressing 102 more difficult to remove. Once drape layer 162 is applied and seals the wound dressing 102 to the patient 158, wound dressing 102 may be used in conjunction with the system 100 in order to establish a negative pressure gradient within wound dressing 102.

[0045] The configurations and layers 108-118 of wound dressing 102 are configured to allow a negative pressure gradient to be established throughout wound dressing 102 in order to draw fluids from the wound bed into wound dressing 102, while retaining the absorbed fluids within the wound dressing 102. A negative pressure gradient is established throughout the wound dressing 102 by connecting wound dressing 102 to a pump via tubing 104 and a connection assembly 106, and using wound dressing 102 as part of a wound therapy system. Referring now to FIG. 4, a cross- sectional view of the connection assembly 106 is shown, according to an exemplary embodiment. Connection assembly 106 connects to opening 160 within drape layer 108, in order to provide a connection between wound dressing 102 and tubing 104. Connection assembly 106 is configured to be positioned at the opening 160 (a hole, airway, channel) through drape layer 108, such that connection assembly 106 can be coupled to the drape layer 108 while in fluid communication with the first wicking layer 110. Connection assembly 106 generally includes perforated hydrophobic filter 150, a perforated indicator 152, an adhesive ring 154, and a felted foam layer 156. [0046] The perforated hydrophobic filter 150 is fitted to the opening 160 within drape layer 108. Adhered to the perforated hydrophobic filter 150 is the adhesive ring 154, which is pressure sensitive. Adhesive ring 154 acts to form a seal of the perforated hydrophobic filter 150 to wound dressing 102. Perforated hydrophobic filter 150 acts to block fluids from traveling into the tubing 104 when a negative pressure gradient is established throughout the wound dressing 102. This allows wound dressing 102 to fill with fluids and retain as much fluid as possible within superabsorbent layer 114. In some embodiments, perforated hydrophobic filter 150 comprises a single perforation, having a diameter within a range of between approximately 0.3mm and 1.2mm. Perforated hydrophobic filter 150 may be permeable to air, but not fluid. When wound dressing 102 is full (i.e., when the absorbent capacity of wound dressing 102 is met), perforated hydrophobic filter 150 will no longer be able to prevent fluid from entering into the connection assembly 106. In some embodiments, a small perforation within perforated hydrophobic filter 150 allows fluid to pass therethrough, only once the wound dressing 102 has reached maximum absorption capacity. Accordingly, passage of fluid through the perforated hydrophobic filter 150 is associated with a full wound dressing 102.

[0047] In some embodiments, connection assembly 106 comprises a felted foam layer 156. Felted foam layer 156 may be constructed using the same material and felting process as described in reference to hydrophobic foam layer 112. Felted foam layer 156 is configured to allow airflow therethrough and to resist the flow of fluid therethrough such that fluid in wound dressing 102 is directed to superabsorbent layer 114 when absorbent capacity is available in the dressing 102. The felted foam layer 156 thereby substantially aids in preventing the flow of fluid into the connection assembly 106 when absorbent capacity is available in the dressing 102. Felted foam layer 200 may include three to five times felted foam. Felted foam layer 156 may be adhered to an underside of perforated hydrophobic filter 150, such that fluid must pass through felted foam layer 156 before reaching the perforated hydrophobic filter 150.

[0048] Once fluid has passed through the perforated hydrophobic filter 150, fluid encounters perforated indicator 152. Perforated indicator 152 has a perforation extending therethrough, such that fluid can pass through the perforation. The perforated indicator 152 may comprise a fluid-activated indicator. In some embodiments, perforated indicator 152 comprises a polyvinylidene fluoride or polyvinylidene difluoride sheet of material, which is bonded by a fusible fiber to the hydrophobic perforated filter 150. An icon may be printed underneath the sheet of material, which is only revealed once the indicator changes its transparency in response to the fluid.

In other embodiments perforated indicator 152 may comprise a white-to-red indicator, configured to change transparency and provide a visual indication of when fluid has reached the perforated indicator 152 within connection assembly 106. In still other embodiments, perforated indicator 152 includes a dye that is painted, printed, or otherwise deposited on the hydrophobic perforated filter 150. When perforated indicator 152 changes colors, or otherwise provides an indication that fluid has reached the connection assembly 106, a visual indication is given to the patient or a caregiver that wound dressing 102 has reached the maximum fluid absorption capacity and needs to be replaced. Perforated indicator 152 is configured to provide this visual indication before fluid is able to enter into tubing 104 and cause any damage to the pump. Further details regarding connection assembly 106 and its components are described in greater detail in U.S. Patent Application No. 62/848,958, filed May 16, 2019, the entire disclosure of which is incorporated by reference herein.

[0049] Referring now to FIGS. 7-8, the tested absorption capacity of wound dressing 102 over a period of time is shown, according to various exemplary embodiments. First referring to FIG. 7, a graph 700 showing the amount of fluid absorption within wound dressing 102 is shown, according to an exemplary embodiment. In the graph 700, data was collected from a wound dressing 102 that was void of a felted foam layer 156 within connection assembly 106. In testing, a 15cm x 15cm wound dressing 102 was able to absorb 45mL of saline throughout the time period, and after the negative pressure gradient had been applied. Now referring to FIG. 8, a graph 800 showing the amount of fluid absorption within wound dressing 102 is shown, according to another exemplary embodiment. In the graph 800, data was collected from a wound dressing 102 that included the felted foam layer 156 within the connection assembly 106. In testing, a 15cm x 15cm wound dressing 102 was able to absorb 50mL of saline throughout the time period, and after the negative pressure gradient had been applied. Thus, the incorporation of felted foam layer 156 within wound dressing 102 aids in increasing the absorption capacity of wound dressing 102. In other embodiments, wound dressing 102 may be capable of absorbing greater quantities of fluids. The testing results are meant to be illustrative, and should be construed as non-limiting.

[0050] According to exemplary embodiments, wound dressing 102 has multiple advantages over previous wound dressings. Wound dressing 102 provides for superior wound exudate and fluid management in comparison to traditional wound dressings. Wound dressing 102 provides a significantly lower cost alternative to traditional wound dressings used in conjunction as part of system 100. Advantageously, the configuration and layers 108-118 of wound dressing 102 are configured to allow a negative pressure gradient to be established throughout wound dressing 102, while retaining absorbed fluids within wound dressing 102 until wound dressing 102 reaches a maximum absorption capacity. The incorporation of multiple wicking layers surrounding superabsorbent layer aid in retaining fluid within superabsorbent layer, which allows the dressing to absorb maximum fluids. Additionally, the inclusion of a hydrophobic foam layer further prevents fluids from escaping the superabsorbent layer 114 due to the hydrophobic foam layer 112 repelling said fluids. Wound dressing 102 is capable of resisting the compressive nature of the atmospheric pressure on the superabsorbent layer 114 as it swells with fluid, in order to provide a reasonable compromise between performance and cost of the wound dressing 102.

Configuration of Exemplary Embodiments

[0051] As utilized herein, the terms “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and are considered to be within the scope of the disclosure.

[0052] The construction and arrangement of the systems and methods as shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, the position of elements can be reversed or otherwise varied and the nature or number of discrete elements or positions can be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. The order or sequence of any process or method steps can be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present disclosure.

Claims

WHAT IS CLAIMED IS:

1. A wound dressing comprising: a perforated silicone layer configured to engage a wound bed, and having a first side and a second side, the second side configured to face the wound bed; a first wicking layer having a first side and a second side, the second side configured to face the first side of the perforated silicone layer; a superabsorbent layer having a first side and a second side, the second side configured to face the first side of the first wicking layer; a hydrophobic foam layer having a first side and a second side, the second side configured to face the first side of the superabsorbent layer; a second wicking layer having a first side and a second side, the second side configured to face the first side of the hydrophobic foam layer; and a drape layer having a first side and a second side, the second side configured to face the first side of the second wicking layer, wherein a border of the first side of the first wicking layer is adhered to the second side of the second wicking layer, forming an adhesive border surrounding the superabsorbent layer and the hydrophobic foam layer such that the superabsorbent layer and the hydrophobic foam layer are free- floating between the first wicking layer and the second wicking layer, and wherein the hydrophobic foam layer is configured to repel fluid to assist with fluid manifolding throughout the wound dressing.

2. The wound dressing of Claim 1, further comprising a tube coupled to the drape layer via an opening in the drape layer and configured to couple to a pump to operate to establish a negative pressure at the drape layer and throughout the wound dressing in order to draw fluids through the wound dressing towards the drape layer.

3. The wound dressing of Claim 2, wherein the opening in the drape layer has a diameter of between 10 mm and 15 mm.

4. The wound dressing of Claim 2, further comprising: a hydrophobic filter comprising a perforation extending therethrough; an indicator coupled to a first side of the hydrophobic filter and positioned proximate the perforation; a felted foam layer coupled to a second side of the hydrophobic foam layer and fluidly communicable with the indicator via the perforation; and a connection pad coupled to the first side of the hydrophobic filter via an adhesive ring and couplable to the tube.

5. The wound dressing of Claim 4, wherein the felted foam layer allows liquid to flow through towards the indicator.

6. The wound dressing of Claim 5, wherein the indicator is configured to change colors in response to contacting fluid, providing an indication of when the wound dressing has reached a fluid handling capacity.

7. The wound dressing of Claim 6, wherein the indicator comprises a white to red indicator.

8. The wound dressing of Claim 6, wherein the indicator comprises a polyvinylidene fluoride material that is bonded by a fusible fiber to the hydrophobic filter.

9. The wound dressing of Claim 4, wherein the perforation has a diameter of between 0.3 mm and 1.2 mm.

10. The wound dressing of Claim 1, wherein a perimeter of the perforated silicone layer extends beyond a perimeter of the adhesive border formed by the first wicking layer and the second wicking layer.

11. The wound dressing of Claim 10, wherein a perimeter of the drape layer is substantially even with the perimeter of the perforated silicone layer.

12. The wound dressing of Claim 10, wherein a perimeter of the drape layer extends beyond the perimeter of the perforated silicone layer, such that the drape layer extends past the perforated silicone layer.

13. The wound dressing of Claim 12, wherein the drape layer extends past the perforated silicone layer by between 10 mm and 20 mm.

14. The wound dressing of Claim 1, wherein the drape layer comprises a first drape layer and a second drape layer, the first drape layer configured to have a perimeter substantially even with the perimeter of the perforated silicone layer, and the second drape layer comprising an adhesive coated ring configured to extend past the perimeter of the first drape layer and extend past the perimeter of the first drape layer by between 10 mm to 20 mm.

15. The wound dressing of Claim 14, wherein the second drape layer is configured to adhere the wound dressing to skin of a patient surrounding the wound bed.

16. The wound dressing of Claim 1, further comprising: a first release liner coupled to the second side of the perforated silicone layer and removable to expose the perforated silicone layer.

17. The wound dressing of Claim 1, wherein the drape layer comprises one of a polyurethane or polyethylene foam.

18. The wound dressing of Claim 1, wherein a border of the second side of the drape layer is coated with an acrylic adhesive configured to adhere to a skin of a patient.

19. The wound dressing of Claim 18, further comprising: a second release liner coupled to the border of the second side of the drape layer and removable to expose the border of the drape layer.

20. The wound dressing of Claim 1, wherein one or more of the first wicking layer and the second wicking layer comprise a non-woven material.

21. The wound dressing of Claim 20, wherein the non-woven material comprises at least one of a polyethylene or a polyethylene terephthalate.

22. The wound dressing of Claim 1, wherein the second side of the first wicking layer is bonded via a fusible fiber to the first side of the perforated silicone layer.

23. The wound dressing of Claim 1, wherein the first side of the second wicking layer is bonded via a fusible fiber to the second side of the drape layer.

24. The wound dressing of Claim 1, wherein the superabsorbent layer comprises a superabsorbent polymer.

25. The wound dressing of Claim 24, wherein the superabsorbent polymer comprises a super absorbent powder, an acetate and ethylene copolymer, and a fiber material.

26. The wound dressing of Claim 25, wherein the superabsorbent layer is structured to be slightly porous with a high density.

27. The wound dressing of Claim 1, wherein the hydrophobic foam layer comprises a thin layer of open-celled hydrophobic foam.

28. The wound dressing of Claim 1, wherein the hydrophobic foam layer has a thickness of between 2 mm and 6 mm.

29. The wound dressing of Claim 1, wherein the hydrophobic foam layer is felted.

30. A wound therapy system comprising: a pump; a tube coupled to the pump; a negative pressure interface assembly; and a wound dressing coupled to the tube via the assembly, the wound dressing comprising: a perforated silicone layer configured to engage a wound bed, and having a first side and a second side, the second side configured to face the wound bed; a first wicking layer having a first side and a second side, the second side configured to face the first side of the perforated silicone layer; a superabsorbent layer having a first side and a second side, the second side configured to face the first side of the wicking layer; a hydrophobic foam layer having a first side and a second side, the second side configured to face the first side of the superabsorbent layer; a second wicking layer having a first side and a second side, the second side configured to face the first side of the hydrophobic foam layer; and a drape layer having a first side and a second side, the second side configured to face the first side of the second wicking layer.

31. The wound therapy system of Claim 30, wherein the pump operates to establish a negative pressure throughout the wound dressing in order to draw fluids through the wound dressing and towards the tubing.

32. The wound therapy system of Claim 31, wherein the assembly comprises: a hydrophobic filter comprising a perforation extending therethrough; an indicator coupled to a first side of the hydrophobic filter and positioned proximate the perforation; a felted foam layer coupled to a second side of the hydrophobic foam layer and fluidly communicable with the indicator via the perforation; and a connection pad coupled to the first side of the hydrophobic filter via an adhesive ring and coupleable to the tube.

33. The wound therapy system of Claim 32, wherein the indicator is configured to change colors in response to contacting fluid, providing an indication of when the wound dressing has reached a fluid handling capacity.

34. The wound therapy system of Claim 30, further comprising: a first release liner coupled to the perforated silicone layer and removable to expose the perforated silicone layer; and a second release liner coupled to a border of the drape layer and removable to expose the drape layer, wherein the border of the drape layer extends past the perforated silicone layer and comprises an acrylic adhesive configured to adhere the wound dressing to a skin of a patient surrounding the wound bed.

35. The wound therapy system of Claim 34, wherein the second release liner is configured to release from the drape layer border in two or four sections.

36 The wound therapy system of Claim 34, wherein the drape layer extends past the perforated silicone layer by between 10 mm and 20 mm.

37. The wound therapy system of Claim 34, wherein the drape layer comprises a first drape layer and a second drape layer, the first drape layer configured to have a perimeter substantially even with the perimeter of the perforated silicone layer, and the second drape layer comprising an adhesive coated ring configured to extend past the perimeter of the first drape layer by between 10 mm to 20 mm

38. A method of applying a wound dressing, comprising: exposing a perforated silicone layer of the wound dressing by removing a first release liner from the dressing, the perforated silicone layer forming a portion of a central region of the wound dressing; aligning the central region of the dressing with a wound bed of a patient; sealing the perforated silicone layer to the patient around the wound bed; operating a pump coupled to the central region of the dressing to verify that a seal is established between the perforated silicone layer and the patient; exposing an acrylic adhesive border of the dressing in the form of a drape layer by removing a second release liner from the dressing, the acrylic adhesive border at least partially surrounding the perforated silicone layer; and adhering the acrylic adhesive border to the patient.

39. The method of Claim 38, further comprising further operating the pump to draw fluid through the wound dressing while maintaining the seal.

40. A system for treating a tissue site, comprising: a dressing comprising: an interface layer in contact with the tissue site; a dressing core configured to be in fluid communication with the tissue site through the interface layer, the dressing core comprising a superabsorbent layer disposed between a first wicking layer and a second wicking layer, and a manifold disposed between the superabsorbent layer and the first wicking layer; and a drape disposed over the interface layer and the dressing core, and a negative pressure source configured to be in fluid communication with the tissue site through the drape.

41. The system of Claim 40, wherein the interface layer comprises a perforated silicone.

42. The system of Claim 41, wherein the perforated silicone comprises a silicone adhesive on a bottom side of the interface layer configured to adhere the dressing to a skin of a patient.

43. The system of Claim 40, further comprising a first release liner coupled to a bottom side of the interface layer and removable to expose the interface layer.

44. The system of Claim 40, wherein a perimeter of the interface layer extends beyond a perimeter of the dressing core.

45. The system of Claim 44, wherein a perimeter of the drape is substantially even with the perimeter of the interface layer.

46. The system of Claim 44, wherein a perimeter of the drape extends beyond the perimeter of the interface layer, such that the drape extends past the interface layer.

47. The system of Claim 46, wherein the drape extends past the interface layer by between 10 mm and 20 mm.

48. The system of Claim 40, wherein a border of a bottom side of the drape is coated with an acrylic adhesive configured to adhere to a skin of a patient.

49. The system of Claim 48, further comprising a second release liner coupled to the border of the bottom side of the drape and removable to expose the border of the drape layer.

50. The system of Claim 40, wherein the drape comprises one of a polyurethane or polyethylene foam.

51. The system of Claim 40, wherein the manifold is configured to repel fluid to assist with fluid manifolding throughout the dressing.

52. The system of Claim 40, wherein the manifold comprises a hydrophobic foam.

53. The system of Claim 52, wherein the hydrophobic foam comprises a thin layer of open-celled hydrophobic foam.

54. The system of Claim 40, wherein the manifold has a thickness of between 2 mm and 6 mm.

55. The system of Claim 40, wherein the manifold is felted.

56. The system of Claim 40, wherein a border of the first wicking layer is adhered to a border of the second wicking layer, forming an adhesive border surrounding the superabsorbent layer and the manifold.

57. The system of Claim 40, wherein the superabsorbent layer comprises a superabsorbent polymer.

58. The system of Claim 57, wherein the superabsorbent polymer comprises a super-absorbent powder, an acetate and ethylene copolymer, and a fiber material.

59. The system of Claim 40, wherein the superabsorbent layer is structured to be slightly porous with a high density.

60. The system of Claim 40, wherein one or more of the first wicking layer and the second wicking layer comprise a non-woven material.

61. The system of Claim 60, wherein the non-woven material comprises at least one of a polyethylene or a polyethylene terephthalate.

62. The system of Claim 40, wherein the first wicking layer is boded via a fusible fiber to the interface layer.

63. The system of Claim 40, wherein the second wicking layer is bonded via a fusible fiber to the drape.

64. The system of Claim 40, further comprising a connection structure, the connection structure configured to fluidly couple the negative pressure source to the dressing.

65. The system of Claim 64, wherein the connection structure is coupled to a tube of the negative pressure source.

66. The system of Claim 64, wherein the connection structure comprises: a hydrophobic filter comprising a perforation extending therethrough; an indicator fluidly coupled to the hydrophobic filter and positioned proximate the perforation; and a felted foam layer fluidly coupled to the manifold and fluidly communicable with the indicator via the perforation.

67. The system of Claim 66, wherein the felted foam layer allows liquid to flow through towards the indicator.

68. The system of Claim 67, wherein the indicator is configured to change colors in response to contacting fluid, providing an indication of when the dressing has reached a fluid handling capacity.

69. The system of Claim 68, wherein the indicator comprises a white to red indicator.

70. The system of Claim 68, wherein the indicator comprises a polyvinylidene fluoride material that is bonded by a fusible fiber to the hydrophobic filter.

71. The system of Claim 66, wherein the perforation has a diameter of between 0.3 mm and 1.2 mm.

72. A wound dressing, comprising: a patient interface layer having a plurality of perforations, the patient interface layer configured to engage a wound bed; a first wicking layer atop the patient interface layer; a superabsorbent layer atop the first wicking layer; a manifold layer atop the first wicking layer; a second wicking layer atop the manifold layer; a first drape layer atop the manifold layer; and a second drape layer atop the first drape layer, wherein a border of the second drape layer extends beyond a border of the first drape layer and is coated with an acrylic adhesive configured to adhere the wound dressing to a skin of a patient, and wherein the first wicking layer is adhered to a border of the second wicking layer, forming an adhesive border surrounding the superabsorbent layer and the manifold layer such that the superabsorbent layer and the manifold layer are free-floating between the first wicking layer and the second wicking layer, and wherein the manifold layer is configured to repel fluid to assist with fluid manifolding throughout the wound dressing.

73. The wound dressing of Claim 72, wherein the first drape layer is substantially free of adhesive.

74. The wound dressing of Claim 72, wherein the second drape layer is substantially ring-shaped and comprises a central opening.

75. The wound dressing of Claim 72, wherein the border of second drape layer extends past the border of first drape layer by between 10 mm and 20 mm.