CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of priority to U.S. Provisional Application No. 62/937,015, filed on November 18, 2019, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] The present disclosure relates to dressings for treating wounds. Many wounds exude fluid (e.g., blood, pus, etc.). Dressings for such wounds may include absorbent materials or other features that attempt to manage the fluid, for example with the goal of absorbing all fluid from a wound.

[0003] Conventional absorbent dressings are bulky, which may create difficulty in applying the dressings and inconvenience for patients. To address these issues, some dressings may include superabsorbent materials which swell when absorbing fluid. Superabsorbent materials and structures are often relatively rigid compared to other elements of a dressing, such that reducing the rigidity of the superabsorbent materials and structures may increase the ability of a superabsorbent dressing to conform to the contours of a patient’s anatomy at a wound site. Increased conformability may improve comfort of the dressing for the patient and help the dressing stay adhered to a patient.

SUMMARY

[0004] One embodiment of the present disclosure is a method for manufacturing a dressing. The method includes obtaining a superabsorbent structure that includes a superabsorbent material and an adhesive, mechanically disrupting the superabsorbent structure, and coupling the superabsorbent structure to one or more additional materials to form the dressing.

[0005] In some embodiments, mechanically disrupting the superabsorbent structure increases a conformability of the superabsorbent structure. Mechanically disrupting the superabsorbent structure may increase the conformability of the superabsorbent structure by at least 30 percent. Mechanically disrupting the superabsorbent structure may increase the conformability of the superabsorbent structure by approximately 70 percent. In some embodiments, mechanically disrupting the superabsorbent structure includes folding the superabsorbent structure.

[0006] In some embodiments, obtaining the superabsorbent structure includes obtaining an extended sheet of the superabsorbent structure. Mechanically disrupting the superabsorbent structure includes pulling the extended sheet around one or more rollers.

[0007] In some embodiments, obtaining the superabsorbent structure includes obtaining an extended sheet of the superabsorbent structure. Mechanically disrupting the superabsorbent structure includes engaging the extended sheet with a bar having a rectangular cross-section. Engaging the extended sheet may include pulling the extended sheet along the bar such that the extended sheet changes direction at the bar.

[0008] In some embodiments, mechanically disrupting the superabsorbent structure includes at least one of scoring, scrunching, or stretching the superabsorbent structure. In some embodiments, coupling the superabsorbent structure to one or more additional materials to form the dressing includes coupling the superabsorbent structure to a wound contact layer and an outer fdm layer.

[0009] Another implementation of the present disclosure is a dressing. The dressing includes a wound contact layer, an outer film layer, and a superabsorbent layer positioned between the wound contact layer and the outer film layer. The superabsorbent layer includes a superabsorbent material and an adhesive. The superabsorbent layer has a mechanically-disrupted structure configured to facilitate conformability of the dressing.

[0010] In some embodiments, the mechanically-disrupted structure comprise a fold or score in the superabsorbent layer. The mechanically-disrupted structure may include a plurality of cracks in the superabsorbent layer. The mechanically-disrupted structure may include a plurality of broken adhesive bonds in the superabsorbent layer.

[0011] In some embodiments, the wound contact layer includes a perforated silicone. In some embodiments, the outer film layer includes a polyurethane film having a moisture vapor transmission rate greater than approximately 2600g/m2/day.

[0012] In some embodiments, when the superabsorbent layer is positioned on an edge of a horizontal planar surface with a first half of the superabsorbent layer positioned on the surface and secured to the surface and a second half of the superabsorbent layer extending from the first half of the superabsorbent layer and outwardly from the edge of the surface, the mechanically-disrupted structure of the superabsorbent layer is such that a leading edge of the second half of the superabsorbent layer bends downwardly by at least 20 percent of a length of the superabsorbent layer under its own weight.

[0013] In some embodiments, the dressing includes a manifolding layer positioned between the superabsorbent layer and the wound contact layer and a connection pad coupled to the outer film layer and configured to provide fluid communication between the manifolding layer and a tube coupled to the connection pad.

[0014] Another implementation of the present disclosure is a manufacturing assembly. The manufacturing assembly includes a dispenser configured to dispense a sheet comprising a superabsorbent material and an adhesive and a receiver configured to receive the sheet from the dispenser. The receiver is spaced apart from the dispenser. A plurality of engagement members is arranged to mechanically disrupt the sheet as the sheet is transferred from the dispenser to the receiver.

[0015] In some embodiments, the plurality of engagement members include rollers. The rollers are positioned at staggered locations such that the sheet changes direction at each of the rollers. The sheet may change directions by at least 45 degrees at each of the rollers. The sheet may change directions by at least 160 degrees at one or more of the rollers.

[0016] In some embodiments, the plurality of engagement members includes either two, three, or four engagement members. In some embodiments, at least one of the plurality of engagement members comprises a bar having a rectangular cross-section. In some embodiments, the engagement members are configured to mechanically disrupt the sheet such that the sheet is at least 30 percent more conformable at the receiver than at the dispenser.

[0017] Another implementation of the present disclosure is a negative pressure wound therapy system. The system includes a pump and a dressing in pneumatic communication with the pump.

The dressing includes a wound contact layer, an outer film layer, a superabsorbent layer positioned between the wound contact layer and the outer film layer; and a manifolding layer positioned between the wound contact layer and the superabsorbent layer. The superabsorbent layer is configured to allow air to flow therethrough from the manifolding layer towards the pump, and the superabsorbent layer has a mechanically-disrupted structure configured to facilitate conformability of the dressing. [0018] The mechanically-disrupted structure may include a fold or score in the superabsorbent layer. The mechanically-disrupted structure may include a plurality of cracks in the superabsorbent layer. In some embodiments, when the superabsorbent layer is positioned on an edge of a horizontal planar surface with a first half of the superabsorbent layer positioned on the surface and secured to the surface and a second half of the superabsorbent layer extending from the first half of the superabsorbent layer and outwardly from the edge of the surface, the mechanically-disrupted structure of the superabsorbent layer is such that a leading edge of the second half of the superabsorbent layer bends downwardly by at least 20 percent of a length of the superabsorbent layer under its own weight. [0019] In some embodiments, the negative pressure wound therapy system includes a tube coupled to the pump and a connection pad coupled to the tube and the outer film layer. The manifolding layer is in pneumatic communication with the pump via a channel through the superabsorbent layer, a hole in the outer film layer, the connection pad, and the tube.

BRIEF DESCRIPTION OF THE DRAWINGS [0020] FIG. 1 is an exploded view of a superabsorbent dressing, according to an exemplary embodiment.

[0021] FIG. 2 is a perspective view of the superabsorbent dressing of FIG. 1, according to an exemplary embodiment.

[0022] FIG. 3 is a cross-sectional side view of the dressing of FIG. 1, according to an exemplary embodiment.

[0023] FIG. 4 is a first schematic illustration of layers of the dressing of FIG. 1, according to an exemplary embodiment. [0024] FIG. 5 is a second schematic illustration of layers of the dressing of FIG. 1, according to an exemplary embodiment.

[0025] FIG. 6 is an illustration of a negative pressure wound therapy system with a superabsorbent dressing, according to an exemplary embodiment.

[0026] FIG. 7 is a flowchart of a process for manufacturing a conformable superabsorbent dressing, according to an exemplary embodiment.

[0027] FIG. 8 is diagram of a manufacturing assembly for use in manufacturing a conformable superabsorbent dressing, according to an exemplary embodiment.

[0028] FIG. 9 is a diagram of another manufacturing assembly for use in manufacturing a conformable superabsorbent dressing, according to an exemplary embodiment.

[0029] FIG. 10 is an illustration of an experiment for testing the conformability of a superabsorbent structure.

[0030] FIG. 11 is a before -and-after illustration of a superabsorbent structure undergoing mechanical disruption, according to an exemplary embodiment.

DETAILED DESCRIPTION

[0031] Referring now to FIG. 1, an exploded view of a superabsorbent dressing 100 is shown, according to an exemplary embodiment. The superabsorbent dressing 100 may be similar to, for example, a KERRAFOAM™ Gentle Border Foam Dressing by Crawford Woundcare Limited and KCI™

[0032] In the example shown, the superabsorbent dressing includes an outer fdm layer (drape) 102, a first wicking layer 104 adjacent the outer film layer 102, a hydrophilic foam layer 105 adjacent the first wicking layer 104, a superabsorbent structure 106 adjacent the first wicking layer 104, a second wicking layer 108 adjacent the superabsorbent structure 106, and a wound contact layer 110 adjacent the second wicking layer 108. As shown, the first wicking layer 104 is between the drape 102 and the hydrophilic foam layer 105, the hydrophilic foam layer 105 is between the first wicking layer 104 and the superabsorbent structure 106, the superabsorbent structure 106 is between the hydrophilic foam layer 105 and the second wicking layer 108, and the second wicking layer 108 is between the hydrophilic foam layer 105 and the wound contact layer 110.

[0033] In the example shown, the drape 102 includes a non-wound-facing (first) side 112 and a wound-facing (second) side 114. The first side 112 is positioned to be exposed to an ambient environment, while the second side 114 faces the first wicking layer 104. The first wicking layer 104 has a non-wound-facing (first) side 118 and a wound-facing (second side) 120, with the first side 118 of the first wicking layer 104 facing (e.g., contacting) the second side 114 of the drape 102. The second side 120 of the first wicking layer 104 faces (e.g., contacts) a first side 124 of the hydrophilic foam layer 105. The hydrophilic foam layer 105 also has a second side 126 opposite the first side 124 and facing (e.g., contacting) a first side 130 of the superabsorbent structure 106. The superabsorbent structure 106 also includes a second side 132 opposite the first side 130 and facing (e.g., contacting) a first side 134 of the second wicking layer 108. The second wicking layer 108 also includes a second side 136 opposite the first side 134 and facing (e.g., contacting) a first side 142 of the wound contact layer 110. The wound contact layer 110 also includes a second side 144 opposite the first side 142 and configured to contact a wound of a patient.

[0034] The outer film layer (drape) 102 is a protective film, for example configured to maintain a moist and protective healing environment at a wound bed when the dressing 100 is applied to a wound. For example, the drape 102 may include a hydrophilic polymer film, for example made of polyurethane. The outer film layer 102 may have a thickness in a range between approximately 15 microns and approximately 50 microns, for example approximately 30 microns. The outer film layer 102 may have a moisture vapor transmission rate (upright cup test) of approximately 2600g/m ² /day or greater. In some embodiments, the drape 102 may comprise a polyurethane film layer with a minimum MVTR of about 800 g/m2/24 hours. The first side 112 of the drape 102 may be water resistant. The drape 102 may form a bacteria barrier that substantially prevents movement of bacteria therethrough.

[0035] The drape 102 includes a periphery (perimeter) 116. In some embodiments, the wound facing (second) side 114 of the drape 102 may be coated with an adhesive, such as an acrylic adhesive. For example, the adhesive may be positioned on substantially a full extent of the second side 114 of the drape 102, such that the second side 114 of the drape 102 may be adhered to the first side 118 of the second wicking layer 108. In other embodiments, the adhesive is positioned only along the periphery 116 of the drape 102.

[0036] The first wicking layer 104 may include a soft nonwoven material, for example a textile material. For example, the first wicking layer 104 may be composed of a polyethylene nonwoven material having a thickness in a range between approximately 0.85 millimeters and 1.15 millimeters, for example 0.95 millimeters. The first wicking layer 104 may be flexible and configured to stretch to allow for swelling of the superabsorbent structure 106. The first wicking layer 104 may also facilitate fluid handling, for example by distributing fluid laterally across the dressing 100 to improve evaporation of fluid through the outer film layer 102. The first wicking layer 104 may also be configured to contribute to the dressing 100 being soft to the touch when contacted on the outer film layer 102. The first wicking layer 104 is thereby configured to improve the comfort of the dressing 100 for a patient. In some embodiments, the first wicking layer 104 is omitted. The first wicking layer 104 includes a first side 118 and a second side 120 opposite the first side 118.

[0037] The first wicking layer 104 includes a periphery (perimeter) 122. In some embodiments, the periphery 116 of the drape 102 may bound an area larger than the periphery 122 of the first wicking layer 104. The area bound by the periphery 122 of the first wicking layer 104 may be contained within the area bound by the periphery 116 of the drape 102. [0038] The hydrophilic foam layer 105 may include an open-cell foam, for example a polyurethane foam. The hydrophilic foam layer 105 may have a thickness of approximately 2 millimeters. Other thicknesses may be used in other embodiments. The hydrophilic foam layer 105 is configured to absorb fluid and allow fluid to flow therethrough, for example from the superabsorbent structure 106 to the first wicking layer 104. The hydrophilic foam layer 105 may be hydrophilic, such that the hydrophilic foam layer 105 is configured to attract water or other fluid, such as a wound fluid. The hydrophilic foam layer 105 may be flexible and compressible, thereby improving comfort of the dressing 100.

[0039] The hydrophilic foam layer 105 includes a first side 124 and a second side 126 opposite the first side. The hydrophilic foam layer 105 also includes a periphery (perimeter) 128. In some embodiments, the periphery 122 of the first wicking layer 104 bounds an area lager than the periphery 128 of the foam layer. The area bound by the periphery 128 of the foam layer 105 may be contained within the area bound by the periphery 122 of the first wicking layer 104.

[0040] The superabsorbent structure 106 may include a superabsorbent material and one or more substrate or binding materials, and is configured to absorb fluid from a wound bed. As described in further detail below, the superabsorbent structure 106 may be constructed as a composite layer that includes a first nonwoven layer and a second nonwoven layer with a polyvinyl acetate (PVA) adhesive layer disposed on a side of the first nonwoven layer facing the second nonwoven layer. For example, a PVA adhesive layer may be disposed on a side of the second nonwoven layer facing the first nonwoven layer. In some embodiments, a superabsorbent particle layer, such as a sodium polyacrylate superabsorbent powder may be sprayed (or otherwise applied) onto either or both of the PVA adhesive layers. The PVA adhesive layer coated faces of the first nonwoven layer and the second nonwoven layer may be brought into contact, such that the first nonwoven layer is bonded to the second nonwoven layer, with the superabsorbent particle interspersed between throughout the PVA adhesive. The PVA adhesive may intersperse into the first and second non-woven layers. The faces coated with the PVA adhesive may be coextensive. The superabsorbent structure 106 may be heated to cure the PVA adhesive to form the composite layer. In some embodiments, the nonwoven layers are configured to provide fluid wicking to facilitate distribution of fluid laterally in the superabsorbent structure 106. The superabsorbent particle layer is configured to absorb fluid, for example swelling when fluid is absorbed to increase a fluid handling capacity of the dressing 100.

The PVA adhesive may be applied so as to be permeable to fluid and to allow a degree of swelling of the superabsorbent particles.

[0041] As described in detail below, the superabsorbent structure 106, once cured, may have a certain degree of rigidity may substantially be provided with a mechanically-disrupted structure that improves the flexibility and conformability of the superabsorbent structure 106. For example, the superabsorbent structure 106 may be scrunched, scored, stretched, folded, manipulated, etc. such that the superabsorbent structure 106 includes a mechanically-disrupted structure that may include cracks, wrinkles, breaks, creases, internal disconnections, breakdowns in the adhesion between portions of the superabsorbent structure 106, etc. which may increase the conformability and/or flexibility of the superabsorbent structure 106. Mechanical disruption of the superabsorbent structure 106 is described in further detail below with reference to FIGS. 7-11.

[0042] The composite layer forming the superabsorbent structure 106 may have a thickness of approximately 68 millimeters or 168 millimeters in various embodiments. In other embodiments, the superabsorbent structure may comprise a thickness in a range of about 0.75 mm to about 1.15 mm (e.g., about 0.95 mm with a tolerance of about 0.2 mm).

[0043] The superabsorbent structure 106 has a first side 130 and a second side 132 opposite the first side 130. The superabsorbent structure 106 has a periphery (perimeter) 133. The periphery 133 of the superabsorbent structure 106 may bound an area coextensive with the area bound by the periphery 128 of the foam layer 105. As positioned in the dressing 100 of FIG. 1, the periphery 133 of the superabsorbent structure 106 may align with the periphery 128 of the foam layer 105.

[0044] The second wicking layer 108 may include a nonwoven material, for example a textile. For example, the second wicking layer 108 may be composed of a polyethylene nonwoven material having a thickness in a range between approximately 0.85 millimeters and 1.15 millimeters, for example 0.95 millimeters. The second wicking layer 108 may be sufficiently flexible and configured to stretch to allow for and accommodate swelling of the superabsorbent structure 106. In the example shown, the wicking layer is configured to provide for fluid flow from a wound bed to the superabsorbent structure 106 and to distribute wound exudate (e.g., horizontally/laterally across the dressing 100) to substantially maximize the absorption capacity of the dressing 100. The second wicking layer 108 may thereby reduce a risk of maceration, increase the fluid capacity of the dressing 100, and increase the duration for which the dressing 100 can be continuously applied to a wound. [0045] The second wicking layer 108 includes a first side 134 and a second side 136 opposite the first side 134. The second wicking layer 108 also includes a periphery (perimeter) 138. The periphery 138 of the second wicking layer 108 may bound an area coextensive with the area bound by the periphery 122 of the first wicking layer 104. The second wicking layer 108 and the first wicking layer 104 may be coupled together around the periphery 138 and the periphery 122 to form a “tea- bag” structure that surrounds and encloses the super absorbent structure 106 and foam layer 105 in a “free-floating” manner.

[0046] The wound contact layer 110 is configured to contact a wound bed while substantially preventing ingrowth of healing tissue to the dressing 100. The wound contact layer 110 may include a perforated silicone material. The wound contact layer 110 may also include a silicone adhesive, for example an adhesive that is permeable to moisture. In some embodiments, the wound contact layer 110 may comprise a silicone adhesive which loses tack when in contact with water or a wound fluid. For example, the wound contact layer 110 may adhere to portions of the epidermis which are substantially dry, but adhere with reduced tack or not adhere to portions of the wound which are wet. Advantageously, in some example embodiments, the silicone adhesive of the wound contact layer 110 may permit at least portions of the dressing to be removed from and re-adhered to the epidermis and/or wound site, facilitating the practitioner’s ability to visually observe the wound site.

[0047] As shown in FIG. 1, the wound contact layer 110 includes a plurality of perforations 140 through the wound contact layer. The perforations 140 can allow fluid to move across the wound contact layer 110, for example from a wound to the second wicking layer 108. In illustrative embodiments, the wound contact layer 110 may have a thickness of about 30 micrometers. The wound contact layer 110 includes a first side 142 and a second side 144 opposite the first side 142.

The second side 144 is configured to contact the wound. A periphery (perimeter) 146 of the wound contact layer 110 defines the extent of the wound contact layer 110. The periphery 146 of the wound contact layer 110 may bound an area coextensive with the area bound by the periphery 116 of the drape 102.

[0048] Referring now to FIG. 2, an assembled isometric view of the dressing 100 is shown, according to an exemplary embodiments. As shown in FIG. 2, the drape 102 and the wound contact layer 110 are visible, with the first wicking layer 104, the hydrophilic foam layer 105, the superabsorbent structure 106 and the second wicking layer 108 assembled in the form of a “tea-bag” or pouch and contained between the drape 102 and the wound contact layer 110.

[0049] Referring now to FIG. 3, a cross-sectional schematic diagram is shown, with the section taken along section line 3 of FIG. 2, illustrating the dressing 100 in use on a tissue site, according to an exemplary embodiment. In the example of FIG. 3, the tissue site includes a wound 302 that extends through the epidermis 304 and the dermis 306 and into subcutaneous tissue 308.

[0050] As shown in FIG. 3, the first wicking layer 104 and the second wicking layer 108 may be coupled, adhered, or welded along an exterior portion of each layer near the perimeter 122 of the first wicking layer and the perimeter 138 of the second wicking layer 108. The second side 120 of the first wicking layer 104 may face the first side 134 of the second wicking layer 108. The perimeter 122 of the first wicking layer may be coextensive with the perimeter 138 of the second wicking layer 108. [0051] In the example of FIG. 3, the first wicking layer 104 and the second wicking layer 108 are welded together by welds 310. The welds 310 are formed by heat sealing. The welds 310 may be formed along the entirety of the perimeter 122 and perimeter 138, or may be formed along a portion thereof. The welds 310 couple the first wicking layer 104 and the second wicking layer 108 such that an internal volume 312 is defined between the first wicking layer 104 and the second wicking layer 108.

[0052] The superabsorbent structure 106 may be disposed within the internal volume 312, as shown in FIG. 3. In some embodiments, at least a portion of the second side 132 of the superabsorbent structure 106 is in contact with at least a portion of the first side 134 of the second wicking layer 108. For example, substantially all of the second side 132 of the superabsorbent structure 106 may be in contact with substantially all of the first side 134 of the second wicking layer 108. [0053] The foam layer 105 may be disposed within the internal volume 312, as shown in the example of FIG. 3. At least a portion of the second side 126 of the foam layer 105 may be in contact with at least a portion of the first side 130 of the superabsorbent structure 106. For example, substantially all of second side 126 of the foam layer 105 may be in contact with substantially all of the first side of the superabsorbent structure 106. At least a portion of the first side 124 of the foam layer 105 may be in contact with at least a portion of the second side 120 of the first wicking layer 104. For example, substantially all of the first side 124 of the foam layer 105 may be in contact with at substantially all of the second side 120 of the first wicking layer 104.

[0054] In some embodiments, the first wicking layer 104 may not be bonded or adhered to the foam layer 105. The foam layer 105 may not be bonded or adhered to the superabsorbent structure 106.

The superabsorbent structure 106 may not be bonded or adhered to the second wicking layer 108. The superabsorbent particles may be contained within the internal volume 312 by the first wicking layer 104, second wicking layer 108, and welds 310. Accordingly, the foam 105 and the superabsorbent structure 106 may be contained with the first wicking layer 104 and the second wicking layer 108 in a pouch-like or free-floating manner.

[0055] In some embodiments, the second wicking layer 108 is adhered or coupled to the wound contact layer 110. For example, a portion of the second side 136 of the second wicking layer 108 may be in contact with a portion of the first side 142 of the wound contact layer 110. For example, a portion of the second side 136 of the second wicking layer 108 may be in contact with a portion of the first side 142 of the wound contact layer 110. In some embodiments, the silicone adhesive of the wound contact layer 110 may cause the portion of the second side 136 of the second wicking layer 108 to adhere to the portion of the first side 142 of the wound contact layer 110.

[0056] As shown in FIG. 3, the second side 114 of the drape 102 is coated with an adhesive 314, for example an acrylic adhesive. A portion of the second side 114 of the drape 102 may be adhered to the first side 118 of the first wicking layer 104 by adhesive 314. A portion of the second side 114 of the drape 102 may be adhered to a portion of the first side 142 of the wound contact layer 110 by the adhesive 314. As illustrated in FIG. 3, the perimeter 116 of the drape 102 may be substantially coextensive with the perimeter 146 of the wound contact layer 110. The drape 102 may be thereby coupled to the wound contact layer 110 to define and exterior of the dressing 100.

[0057] FIG. 3 illustrates the dressing 100 applied to a wound 302. When applied to the wound 302, a portion of the wound contact layer 110 may adhere to epidermis 304, for example at the periwound area, within another portion of the wound contact layer 110 in contact with the wound 302. In a case where the wound 302 is emitting exudate or other wound or bodily fluids, the silicone adhesive of the wound contact layer 110 may reduce in tackiness at areas exposed to such fluid. The wound contact layer 110 may thereby be substantially prevented from adhering to the wound 302.

[0058] During application of the dressing 100 to the wound 302, moisture from the wound 302 is transported across the perforations 140 of the wound contact layer 110 and into contact with the second wicking layer 108. The second wicking layer 108 wicks fluid laterally along the second wicking layer 108, providing lateral distribution of the fluid across the dressing 100. The fluid is transported from the second wicking layer 108 to the superabsorbent structure 106. The fluid may also be transported from the second wicking layer 108 to the first wicking layer 104 at the portions where the first wicking layer 104 and the second wicking layer 108 are in contact near and at the welds 310.

[0059] The composite layer of the superabsorbent structure 106 absorbs and retains the fluid, for example swelling to store an amount of fluid greater than an original volume of the superabsorbent structure 106. Fluid may also be transported from the superabsorbent structure 106 to the foam layer 105, for example via open cells of the foam layer 105. The fluid is then transported from the foam layer 105 to the first wicking layer 104. The wicking layer 104 distributes fluid laterally along the first wicking layer 104, and transports fluid into contact with the drape 102. The drape is configured to allow moisture to evaporate therethrough from the first wicking layer 104 to an ambient environment to create an evaporative gradient from the superabsorbent structure 106 to the ambient environment. At portions where the wound contact layer 110 is adhered to the epidermis, moisture is transported across the perforations 140 in the wound contact layer 110 and across the drape 102, substantially reducing a risk of maceration. The dressing 100 is thereby configured to have an overall moisture vapor transfer rate that allows fluid from the wound to be moved away from the wound and out of the dressing 100 while providing an environment that supports wound healing.

[0060] In some embodiments, the construction of the dressing 100 shown in FIG. 3 provides a reduction in lateral shear forces. For example, a lateral force applied to the drape 102 may be transmitted to the first wicking layer 104 as a result of the adhesive bonds formed by adhesive layer 314. However, with a free-floating “tea-bag” arrangement where the first wicking layer 104 is not adhered to the foam layer 105, the lateral force may be reduced in transmission of the force from the first wicking layer 104 to the foam layer 105 (e.g., due to relative motion of the first wicking layer 104 and the foam layer 105). The force is further reduced by losses in transmission from the foam layer 105 to the superabsorbent structure 106, and from the superabsorbent structure 106 to the second wicking layer 108. Any lateral forces transferred through the dressing 100 to the wound contact layer 110 are thereby substantially reduced. Additionally, the reduced tackiness of the wound contact layer 110 on wet portions of the wound 302 further reduces lateral force transfer to the wound 302. This may improve comfort of the dressing 100 and protect the wound during healing.

[0061] Referring now to FIG. 4, a detailed cross-sectional schematic of the dressing 100 is shown, according to an exemplary embodiment. In particular, a cross-sectional view of the superabsorbent structure 106 is shown in detail as in some embodiments.

[0062] The superabsorbent structure 106 includes a first nonwoven layer 402 and a second nonwoven layer 406. The first nonwoven layer 402 may include a nonwoven textile material and may be configured to provide lateral wicking of fluid. The second nonwoven layer 406 may include a nonwoven textile material and may be configured to provide lateral wicking of fluid. The superabsorbent structure 106 also includes a first adhesive layer 404 disposed on a side of the first nonwoven layer 402 and a second adhesive layer 508 positioned on a side of the second nonwoven layer 406. The first adhesive layer 404 faces the second adhesive layer 408. The first adhesive layer 404 and the second adhesive layer 408 may include a PVA adhesive.

[0063] In the schematic of FIG. 4, a superabsorbent particle layer 410 is disposed between the first adhesive layer 404 and the second adhesive layer 408. For example, superabsorbent particles (e.g., sodium polyacrylate) may be sprayed, distributed, etc. on the first adhesive layer 404 and/or the second adhesive layer 408. The first nonwoven layer 402 and the second nonwoven layer 406 may then be brought together as shown in FIG. 4 to position the superabsorbent particle layer 410 between the first nonwoven layer 402 and the second nonwoven layer 406 and between the first adhesive layer 404 and the second adhesive layer 406. In other embodiments, the superabsorbent particles are positioned on the first nonwoven layer 402 and/or the second nonwoven layer 406 before the adhesive is applied. In other embodiments, the superabsorbent particles are mixed with the adhesive and then applied together to the first nonwoven layer 402 and the second nonwoven layer 406.

[0064] While the schematic of FIG. 4 shows discrete layers of nonwoven material, adhesive, and superabsorbent, the materials may be arranged and interspersed into a mixed composite layer. For example, the adhesive and the superabsorbent may become interspersed, mixed, etc. Also, the adhesive may penetrate the first nonwoven layer 402 and the second nonwoven layer 406. The result may be a composite layer (i.e., the superabsorbent structure 106) that includes the nonwoven material layers, the adhesives, and the superabsorbent particles. In some cases, the superabsorbent structure 106 as shown in FIG. 4 is substantially or partially rigid.

[0065] Referring now to FIG. 5, another detailed cross-sectional schematic of the dressing 100 is schematically shown, according to an exemplary embodiment. In particular, a cross-sectional view of the superabsorbent structure 106 is shown in detail as in some embodiments. As mentioned above, FIG. 5 shows discrete layers for sake of illustration, while in some cases the first nonwoven layer 402, the first adhesive layer 404, the second nonwoven layer 406, the second adhesive layer 408, and/or the superabsorbent particle layer 410 may be intermixed, overlapping, etc. to form a composite.

[0066] FIG. 5 shows the superabsorbent structure 106 having a first nonwoven layer 402, a first adhesive layer 404, a second nonwoven layer 406, a second adhesive layer 408, and a superabsorbent particle layer 410. FIG. 5 illustrates that the first adhesive layer 404 may include a first plurality of disruptions 502. The disruptions 502 may include cracks, wrinkles, breaks, separations, bends, creases, folds, weak points, etc. of the first adhesive layer 404 (e.g., in the PVA adhesive). The disruptions 502 may provide for increased flexibility and conformability of the first adhesive layer 404.

[0067] FIG. 5 also illustrates that the second adhesive layer 408 may include a second plurality of disruptions 504. The disruptions 504 may include cracks, wrinkles, breaks, separations, bends, creases, folds, weak points, etc. of the second adhesive layer 408 (e.g., in the PVA adhesive and in the bonds between the second adhesive layer 408 and the superabsorbent particles and/or the nonwoven layers). The disruptions 504 may provide for increased flexibility and conformability of the second adhesive layer 408. The disruptions 502 and 504 thereby provide for increased flexibility and conformability of the superabsorbent structure 106 and, accordingly, increased flexibility and conformability of the dressing 100.

[0068] Referring now to FIG. 6, an embodiment of the dressing 100 adapted for use in negative pressure wound therapy (NPWT) is shown, according to an exemplary embodiment. In the example of FIG. 6, the dressing 100 is configured to provide for the communication of negative pressure (relative to ambient atmospheric pressure) to the wound 302. As in FIGS. 1-5, the dressing 100 of FIG. 6 includes the drape 102 coupled to the first wicking layer 104 by the adhesive layer 314, the hydrophilic foam layer 105 and superabsorbent structure 106 positioned between the second wicking layer 108 and the first wicking layer 104, and the wound contact layer 110 bonded to the drape 102 by the adhesive layer 314. In the embodiment of FIG. 6, the dressing 100 also includes additional features that facilitate airflow through the dressing 100 to provide for the communication of negative pressure to the wound 302.

[0069] As shown in FIG. 6, the dressing 100 is configured to provide a sealed environment 602 in fluid communication with the wound 302. The drape 102 and the wound contact layer 110 are configured to be adhered (e.g., with a silicone adhesive of the wound contact layer 110) to the epidermis 304 at a periwound area such that the seal between the dressing 100 and the epidermis 304 is substantially airtight. In some embodiments, an additional adhesive (e.g., an acrylic adhesive) is provided at the periphery of the wound contact layer 110 to improve the seal between the dressing 100 and the epidermis 304 (e.g., to reduce leaks between the epidermis and the wound contact layer 110.

A sealed environment 602 is thereby established between the wound 302 and the drape 102.

[0070] In the embodiment shown, the first wicking layer 104, the foam layer 105, the superabsorbent structure 106, and the second wicking layer 108 are contained in the sealed environment 602. In the example of FIG. 6, the dressing 100 also includes a manifold 604 positioned between the second wicking layer 108 and the wound contact layer 110 and in contact with the second wicking layer 108 and the wound contact layer 110. The manifold 604 is configured to allow air to flow therethrough vertically and laterally to facilitate substantially even distribution of negative pressure across the wound 302. The manifold 604 is also configured to provide for movement of fluid from the wound 302 to the second wicking layer 108 via the perforations 140 in the wound contact layer 110. For example, the manifold 604 may include an open-celled polyurethane foam.

[0071] The dressing 100 is also shown to include a port 606 formed through the drape 102 and a port 608 formed through the adhesive layer 314. The port 606 allows airflow through the drape 102 and the port 606 allows airflow through the adhesive layer 314. The ports 606, 608 are aligned to allow airflow through both the drape 102 and the adhesive layer 314 via the ports 606, 608. A connector 610 is coupled to the drape 102 at the port 606, such that the connector 610 is in fluid communication with the sealed environment 602 via the port 606 and the port 608.

[0072] The connector 610 is fluidly coupled to a negative-pressure source 612 via a conduit 614.

For example, the negative-pressure source 612 may include a pump configured to remove air and/or fluid from the sealed environment 602 via the port 606, the port 608, the connector 610, and the conduit 614. The conduit 614 may be a tube, for example having one or more bores defining one or more paths for fluid communication between the negative-pressure source 612 and the dressing 100. [0073] In the embodiment of FIG. 6, the superabsorbent structure 106 includes perforations 616 that allow air and fluid to cross the superabsorbent structure 106 via the perforations 616. For example, the superabsorbent structure 106 may be resistant to airflow therethrough. The perforations 616 may therefore be provided through the superabsorbent structure 106 to provide for communication of negative pressure from the ports 606, 608 to the manifold 604 via the perforations 616.

[0074] The dressing 100 of FIG. 6 is thereby configured for the transportation of air and fluid across the dressing 100. Fluid (e.g., liquid, wound exudate) moves from the wound 302 to the manifold 604 via perforations 140 in the wound contact layer 110. The manifold 604 is configured to allow fluid to move and distribute through the manifold 604 to the second wicking layer 108, which distributes fluid laterally across the dressing and to the superabsorbent structure 106. The superabsorbent structure 106 absorbs and stores fluid in the dressing (i.e., in the superabsorbent particle layer 410 shown in FIGS. 4-5). Fluid may move from the superabsorbent structure 106 to the first wicking layer 104, which distributes the fluid along the drape 102 to facilitate evaporation of the fluid through the drape 102. In some embodiments, fluid is removed from the dressing 100 by the negative-pressure source 612 via the ports 606, 608 and the connector 610, for example to be collected at the negative-pressure source 612. In other embodiments, the connector 610 and/or the ports 606, 608 is provided with a filter that allows air to be removed from the dressing but prevents fluid from entering the conduit 614, for example to protect the negative-pressure source 612 from exposure to wound exudate.

[0075] Negative pressure is provided at the wound by allowing air to flow away from the wound 302 as follows. The perforations 140 in the wound contact layer 110 allow airflow from the wound 302 to the manifold 604. The manifold 604 allows airflow through the manifold in multiple directions, thereby allowing pressure to reach an approximately equal value throughout the manifold 604. Air can flow from the manifold 604 to the hydrophilic foam layer 105 via the perforations 616 in the superabsorbent structure 106. The hydrophilic foam layer 105 may include an open-celled foam that allows from airflow therethrough and distribution of pressure across the foam layer 105.

The first wicking layer 104 and the second wicking layer 108 may include a nonwoven textile that allows air to flow substantially freely across the first wicking layer 104 and the second wicking layer 108. The foam layer 105 is then in fluid communication with the ports 606, 608 which allow air to leave the sealed environment 602 via the connector 610 and the conduit 614. Negative pressure can thus be established at the wound 302 by operation of the negative pressure source 612. [0076] Referring now to FIG. 7, a flowchart of a process 700 of providing a conformable superabsorbent dressing is shown, according to an exemplary embodiment. The process 700 of FIG.

7 may result in a dressing 100 consistent with the embodiments described above and/or shown in FIGS. 1-6. In various other embodiments, the process 700 may result in superabsorbent dressings of other designs. The steps of the process 700 of FIG. 7 can be performed manually and/or by automated manufacturing equipment.

[0077] At step 702, a sheet of a superabsorbent structure is obtained. The superabsorbent structure may include a superabsorbent material and one or more substrate or binding materials, for example sodium polyacyrlate held together with a bilaminate layer of polyvinyl acetate glue. For example, the superabsorbent structure may include a polyvinyl acetate adhesive between two nonwoven layers and including a superabsorbent (e.g., sodium polyacrylate) powder as described above with reference to FIGS. 1-6. The sheet of the superabsorbent structure may include enough of the superabsorbent structure for multiple dressings. The sheet of superabsorbent structure may be obtained as a flat sheet or as a sheet wound on a spool or roll.

[0078] At step 704, the superabsorbent structure is mechanically disrupted. For example, the superabsorbent structure may be scrunched, squished, folded, wrinkled, scored, twisted, bent, etc. to cause mechanical disruption to the superabsorbent structure. In some embodiments, the superabsorbent structure is mechanically disrupted using one or more rollers or other engagement members that engage the superabsorbent structure within a manufacturing line for the dressing. Example of such manufacturing assemblies are shown in FIGS. 8-9 and described in detail with reference thereto.

[0079] FIG. 11 shows a before -and-after schematic view illustrative of the effects of step 706, in which the superabsorbent structure 106 is shown before and after mechanical disruption.

Mechanically disrupting the superabsorbent structure in step 704 provides the superabsorbent structure (originally substantially free of cracks, creases, etc. as shown in the “before” view of FIG.

11) with a mechanically-disrupted structure that may include creases, cracks, reduced binding between adjacent superabsorbent material and substrate material (e.g., polyvinyl acetate adhesive), stretching of the superabsorbent material and substrate material, and/or other deformation or structural change (as shown in “after” pane of FIG. 11). In some embodiments, mechanically disrupting the superabsorbent structure breaks disulphide bonds in the superabsorbent structure. In some embodiments, mechanically disrupting the superabsorbent structure breaks physical bonds to form cracks in the superabsorbent structure, e.g., in a polyvinyle acetate adhesive layer between a first nonwoven layer and a second nonwoven layer. The mechanically-disrupted structure has increased flexibility and conformability as compared to the superabsorbent structure prior to step 704. In some embodiments, mechanically disrupting the superabsorbent structure as in step 704 increases the conformability of the superabsorbent dressing by at least thirty percent, and, in some cases, by approximately seventy percent. [0080] At step 706, the mechanically-disrupted sheet of superabsorbent structure is divided into segments. For example, the sheet may be cut such that a piece of the superabsorbent structure removed from the sheet is suitable for inclusion in a single dressing. For example, the sheet may be sliced at predetermined intervals corresponding to a desired size of the dressings. The sheet of superabsorbent structure may thereby be divided for inclusion in multiple separate dressings.

[0081] At step 708, segments of the superabsorbent structure are coupled other dressing materials to incorporate the segments into dressings. For example, a segment of the superabsorbent structure may be coupled (directly or indirectly) to the wound contact layer 110, the second wicking layer 108, the first wicking layer 104 and the outer film layer 102 to form the dressing 100 of FIG. 1. In some embodiments, step 708 includes confining a segment of superabsorbent structure between two or more other layers (e.g., an outer film layer 102 and a wound contact layer 110, a first wicking layer 104 and a second wicking layer 108) and coupling such layers together around the superabsorbent structure (with or without adhering or bonding the superabsorbent structure directly to another layer). Other modifications to the superabsorbent structure may be made, for example forming a channel (airway, hole, etc.) therethrough to facilitate the communication of negative pressure across the superabsorbent structure as shown in FIG. 6. In other examples, the superabsorbent structure is assembled into various dressings having various materials, arrangements, designs, features, etc. Step 708 thereby results in a dressing that includes a mechanically-disrupted superabsorbent structure having an increased conformability relative to a non-mechanically-disrupted superabsorbent structure. The resulting dressing may therefore also have an increased conformability relative to other superabsorbent dressings.

[0082] Referring now to FIG. 8, an illustration of a manufacturing assembly 800 for mechanically disrupting a sheet 802 of the superabsorbent structure 106 is shown, according to an exemplary embodiment. The manufacturing assembly 800 can be used to execute step 704 of process 700, for example.

[0083] The manufacturing assembly 800 includes a roll stock dispenser 804, receiver rollers 806, and a disruption mechanism 808 arranged between the roll stock dispenser 804 and the receiver rollers 806. The roll stock dispenser 804 is configured to hold a roll of an extended sheet 802 of superabsorbent structure and rotate to dispense the sheet 802. The receiver rollers 806 receive the sheet, for example rotating to pull the sheet 802 across a gap between the roll stock dispenser 804 and the receiver rollers 806. The sheet 802 is thereby transferred from the roll stock dispenser 804 to the receiver rollers 806. The receiver rollers 806 may then move the sheet to further manufacturing equipment configured to execute steps 706 and 708 of process 700.

[0084] The disruption mechanism 808 is configured to engage the sheet as the sheet is transferred from the roll stock dispenser to the receiver rollers 806. In the example shown, the disruption mechanism 808 includes multiple engagement members. In the configuration shown, the sheet 802 is engaged by two engagement members including a roller 810 and a rectangular bar 812. The sheet 802 is pulled around the roller 810 and the rectangular bar 812 which are located at staggered positions such that that sheet 802 changes directions at the roller 810 and at the rectangular bar 812 (e.g., by at least 45 degrees). The rectangular bar 812, in various embodiments, may or may not rotate as the sheet 802 is pulled around the bar. The sheet 802 is mechanically disrupted as it is bent, pulled, stretched, scored, etc. due to interaction with the engagement members (e.g., the roller 810 and the rectangular bar 812).

[001185] As shown in FIG. 8, the disruption mechanism 808 includes engagement members of various shapes, sizes, and positions. For example the engagement members are shown as having circular, oval, diamond-shaped, or triangular cross sections. Various geometries are possible in various embodiments, and the engagement members may have irregular geometries and/or cross- sectional shapes that change along a length of the engagement member. For example, an engagement member may change in thickness along a length of the engagement member such that the sheet 802 is bent or folded by the engagement member both in the direction of the travel of the sheet 802 and across a width of the sheet (e.g., orthogonal to the direction of travel).

[0086] The disruption mechanism 808 of FIG. 8 is designed to allow for customization of the mechanical disruption process by selecting a set of engagement members of the disruption mechanism 808 to be used. That is, the sheet 802 of superabsorbent structure may be brought into contact with various combinations of the engagement members in various executions of step 704 of process 700. The mechanical disruption of the superabsorbent structure can thereby be adapted for sheets 402 of different sizes, thickness, compositions, etc. As shown, the sheet 802 engages two engagement members. In other implementations, the sheet 802 may engage three or four engagement members.

In some cases, the path of the sheet 802 through the engagement members is selected to maximize the mechanical disruption of the sheet 802 while also avoiding tears or rips in the sheet.

[0087] The disruption mechanism 808 thereby provides the sheet 802 dispensed from the roll stock dispenser 804 with a mechanically-disrupted structure while being transferred to the receiver rollers 806. Due to this mechanical disruption, the sheet 802 may be at least thirty percent more conformable at the receiver rollers 806 than at the roll stock dispenser 804. In some embodiments, the sheet 802 is approximately seventy percent more conformable at the receiver rollers 806 than at the roll stock dispenser 804. The sheet 802 can then undergo further processing as described with reference to FIG. 7 to be integrated into a dressing, for example as shown in FIGS. 1-6.

[0088] FIG. 9 shows another manufacturing assembly 950 suitable for mechanically disrupting the structure of the superabsorbent material. As shown in FIG. 9, the manufacturing assembly 950 includes the roll stock dispenser 804 and a receiver roller 806 with a first disruption roller 952, a second disruption roller 956, a third disruption roller 956, and a fourth disruption roller 958 positioned along the path of the sheet 802 between the roll stock dispenser 804 and the receiver roller 806. The sheet 802 is bent sequentially around the first disruption roller 952, the second disruption roller 956, the third disruption roller 956, and the fourth disruption roller 958. The relative positions of the rollers 952-958 cause the sheet 802 to change directions by greater than approximately 160 degrees at the first roller 956, the second roller 956, and the third roller 956. Additionally, the spacing between the rollers 952-958 and the presence of multiple rollers 952-958 may increase the tension in the sheet 802 which contributes to the mechanical disruption of the sheet 802. The manufacturing assembly 950 is thereby configured to output a mechanically-disrupted superabsorbent sheet 802.

[0089] Referring now to FIG. 10, an experimental setup 1000 for assessing the conformability of a dressing is shown, according to an exemplary embodiment. As shown in FIG. 10, the superabsorbent structure 106 (e.g., a superabsorbent material, binding agent, and, in some embodiments first and/or second nonwoven layers) is positioned at an edge 1002 of a horizontal planar surface 1004 (e.g., a table, a lab bench, etc.). A first half 1008 of the superabsorbent structure 106 is positioned on the surface 1004 and secured (held, confined) to the surface 1004, for example by a weight 1006 as shown in FIG. 10. A second half 1010 of the superabsorbent structure 106 extends from the first half 1008 of the superabsorbent structure 106 and extends outwardly from the edge 1002 of the surface 1004. The second half 1010 of the superabsorbent structure 106 is not supported from underneath by the surface 1004, such that the second half 1010 is allowed to curve downward under its own weight. The Applicant presently believes the conformability of the dressing can be assessed by measuring the vertical distance d between the surface 1004 and a distal end 1012 of the second half 1010 of the superabsorbent structure 106.

[0090] In some cases, the distance d can be compared to dimensions of the superabsorbent structure 106 (e.g., length, width, area, thickness, volume) to assess the conformability of the dressing. For example, in some examples herein, the mechanically-disrupted structure of the superabsorbent structure 106 is such that a leading edge of the second half 1010 of the superabsorbent structure 106 bends downwardly (under its own weight) by at least twenty percent of a length of the superabsorbent dressing. The following table provides a set of experimental results that may be achieved by mechanically disrupting the superabsorbent structure and conducting the experiment illustrated in FIG. 10, where the test is performed on an embodiment of the superabsorbent structure 106 having a thickness of approximately 0.95 millimeters.

[0091] As illustrated by these results, mechanically disruption the superabsorbent structure can significantly increase the conformability of the superabsorbent structure and, by extension, dressings that include such mechanically-disrupted structures. Dressings including superabsorbent structures that have been mechanically disrupted as described herein may therefore be easier to apply to a wound, may more comfortable for patients, and may be less likely to lift away from a wound during wear.

[0092] 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 claimed are considered to be within the scope of the disclosure as recited in the appended claims. [0093] It should be noted that the term “exemplary” and variations thereof, as used herein to describe various embodiments, are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (and such terms are not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

[0094] The term “coupled” and variations thereof, as used herein, means the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent or fixed) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members coupled directly to each other, with the two members coupled to each other using a separate intervening member and any additional intermediate members coupled with one another, or with the two members coupled to each other using an intervening member that is integrally formed as a single unitary body with one of the two members. If “coupled” or variations thereof are modified by an additional term (e.g., directly coupled), the generic definition of “coupled” provided above is modified by the plain language meaning of the additional term (e.g., “directly coupled” means the joining of two members without any separate intervening member), resulting in a narrower definition than the generic definition of “coupled” provided above. Such coupling may be mechanical, electrical, or fluidic.

[0095] References herein to the positions of elements (e.g., “top,” “bottom,” “above,” “below”) are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure. [0096] Although the figures and description may illustrate a specific order of method steps, the order of such steps may differ from what is depicted and described, unless specified differently above. Also, two or more steps may be performed concurrently or with partial concurrence, unless specified differently above. All such variations are within the scope of the disclosure.