WO2022101717A1

WO2022101717A1 - Supported drape for negative-pressure therapy dressing

Info

Publication number: WO2022101717A1
Application number: PCT/IB2021/059674
Authority: WO
Inventors: Jonathan G. REHBEIN; Luke Perkins; Shervin JAHANIAN; Enrique L. SANDOVAL
Original assignee: Kci Manufacturing Unlimited Company
Priority date: 2020-11-11
Filing date: 2021-10-20
Publication date: 2022-05-19

Abstract

Disclosed embodiments may relate to dressings and/or drapes configured to provide negative-pressure therapy to a tissue site, such as an incision. In some embodiments, the drape may have an integral, semi-rigid support layer. For example, the support layer may be configured to provide support to the drape around its perimeter, with an interior aperture through the support layer forming the perimeter support. In some embodiments, the support layer may be sandwiched between and coupled to an outer drape layer and a base drape layer, and the base drape layer may have an adhesive surface opposite the support layer. In some embodiments, the base drape layer may have a base aperture concentric with the interior aperture. In some embodiments, the outer drape layer may comprise an interface aperture concentric with and smaller than the interior aperture.

Description

SUPPORTED DRAPE FOR NEGATIVE-PRESSURE THERAPY DRESSING

CROSS-REFERENCE TO REEATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Provisional Application No. 63/112,231, filed on November 11, 2020, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] This disclosure relates generally to tissue treatment systems and more particularly, but without limitation, to dressings, systems, and methods relating to negative-pressure therapy.

BACKGROUND

[0003] Clinical studies and practice have shown that reducing pressure in proximity to a tissue site can augment and accelerate growth of new tissue at the tissue site. The applications of this phenomenon are numerous, but it has proven particularly advantageous for treating wounds. Regardless of the etiology of a wound, whether trauma, surgery, or another cause, proper care of the wound is important to the outcome. Treatment of wounds or other tissue with reduced pressure may be commonly referred to as "negative-pressure therapy," but is also known by other names, including "negativepressure wound therapy," "reduced-pressure therapy," "vacuum therapy," "vacuum-assisted closure," and "topical negative-pressure," for example. Reduced-pressure therapy may provide a number of benefits, including migration of epithelial and subcutaneous tissues, improved blood flow, and microdeformation of tissue at a wound site. Together, these benefits can increase development of granulation tissue and reduce healing times.

[0004] While the clinical benefits of negative-pressure therapy are widely known, improvements to therapy systems, components, and processes may benefit healthcare providers and patients.

BRIEF SUMMARY

[0005] New and useful systems, apparatuses, and methods for managing tissue sites in a negative-pressure therapy environment are set forth in the appended claims. The following description provides non-limiting, illustrative example embodiments to enable a person skilled in the art to make and use the claimed subject matter.

[0006] Disclosed embodiments may relate to dressings and/or drapes configured to provide negative-pressure therapy to a tissue site, such as an incision. In some embodiments, the drape may have an integral, semi-rigid support layer. For example, the support layer may comprise or consist essentially of a mesh. In some embodiments, the support layer may be configured to provide support to the drape only around its perimeter, with an interior aperture through the support layer forming the perimeter support. In some embodiments, the support layer may be sandwiched between and coupled to an outer drape layer and a base drape layer, and the base drape layer may have an adhesive surface opposite the support layer. In some embodiments, the base drape layer may have a base aperture concentric with the interior aperture of the support layer. In some embodiments, the outer drape layer may comprise an interface aperture concentric with and smaller than the interior aperture of the support layer. In some embodiments, the interface aperture may be configured to interface with a dressing assemblage having a manifold, a cover over the manifold, and/or a treatment aperture exposing the manifold.

[0007] In some example embodiments, a drape for negative-pressure therapy on a tissue site may comprise: an outer drape layer; a base drape layer; and a semi-rigid support layer located between and coupled to the outer drape layer and the base drape layer. In some embodiments, the semi-rigid support layer may be configured to render the drape self-supporting. For example, the support layer may be formed of a material with a Young’s Modulus of approximately 0.1 - 10 GPa and a thickness less than about 0.01 inch. In some embodiments, the support layer may be configured to support the drape substantially only around a perimeter of the drape. For example, the support layer may comprise an interior aperture. In some embodiments, the outer drape layer may comprise a first surface, configured to face towards the support layer, and a second surface opposite the first surface; the first surface may be adhesive and the second surface may not be adhesive; the base drape layer may comprise a contact surface configured to contact the tissue site and an exterior surface opposite the contact surface; and both the contact surface and the exterior surface may be adhesive. In some embodiments, the outer drape layer may comprise an interface aperture, the base drape layer may comprise a base aperture, and the interface aperture and the base aperture may be aligned with each other and with the interior aperture of the support layer.

[0008] In some example embodiments, a dressing for providing negative-pressure therapy at a tissue site may comprise: an attachment device having a treatment aperture; a manifold configured to be at least partially exposed to the tissue site through the treatment aperture; a cover configured to be disposed over the manifold and coupled to the attachment device around the manifold; and a drape having an integral, semi-rigid support layer. In some embodiments, the support layer may be configured to support the drape substantially only around a perimeter of the drape. For example, the support layer may comprise an interior aperture, which is larger than the treatment aperture. In some embodiments, the drape may further comprise an outer drape layer and a base drape layer, with the support layer located therebetween. In some embodiments, the outer drape layer may comprise an interface aperture; the base drape layer may comprise a base aperture; the interface aperture may be smaller than the interior aperture of the support layer; and the interface aperture and the base aperture may be aligned with each other and with the interior aperture of the support layer. In some embodiments, the support layer may be stacked between and coupled to both the outer drape layer and the base drape layer, and the base drape layer may comprise an adhesive on a surface opposite the support layer.

[0009] In some example embodiments, a dressing for providing negative-pressure therapy at a tissue site may comprise a drape having an integral, semi-rigid support layer. In some embodiments, the support layer may be embedded within the drape. For example, the support layer may be sandwiched between and coupled to an outer drape layer and a base drape layer. In some embodiments, the support layer may be configured to support the drape substantially only around a perimeter of the drape. For example, the support layer may comprise an interior aperture. In some embodiments, the base drape layer may comprise a base aperture concentric with the interior aperture. In some embodiments, the base drape layer may comprise a surface opposite the support layer which is adhesive. In some embodiments, the outer drape layer may comprise an interface aperture concentric with the interior aperture of the support layer. Some dressing embodiments may further comprise: an attachment device having a treatment aperture; a manifold configured to be at least partially exposed to the tissue site through the treatment aperture; and/or a cover configured to be disposed over the manifold and coupled to the attachment device around the manifold. In some embodiments, the manifold, cover, and attachment device may be pre-formed as a dressing assembly.

[0010] In some example embodiments, a method for manufacturing a drape or dressing may comprise: providing an outer drape layer having adhesive on a first surface and no adhesive on a second surface; providing a support layer having an interior aperture; providing a base drape layer having a base aperture and having adhesive on both a contact surface and an exterior surface; and disposing and adhering the support layer between the outer drape layer and the base drape layer, with the support layer coupled to the first surface of the outer drape layer and coupled to the exterior surface of the based drape layer. In some embodiments, the support layer may be positioned and/or provide support around the perimeter of the drape and the interior aperture may align with the base aperture. In some embodiments, the outer drape layer may further comprise an interface aperture, and the method may further comprise aligning the interface aperture with the interior aperture. In some embodiments, providing the support layer may comprise: providing a polymer film; and forming the interior aperture in the polymer film.

[0011] Objectives, advantages, and a preferred mode of making and using the claimed subject matter may be understood best by reference to the accompanying drawings in conjunction with the following detailed description of illustrative example embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a block diagram of an example embodiment of a therapy system that can provide negative-pressure therapy in accordance with this specification;

[0013] Figure 2 is a graph illustrating example pressure control modes that may be associated with some example embodiments of the therapy system of Figure 1;

[0014] Figure 3 is a graph illustrating another example pressure control mode suitable for some example embodiments of the therapy system of Figure 1 ;

[0015] Figure 4 is an exploded, isometric view of an example embodiment of a dressing that may be associated with an example embodiment of the therapy system of Figure 1; [0016] Figure 5 is a schematic cross-section view illustrating an exemplary system having an exemplary dressing in place on an exemplary tissue site, illustrating additional details that may be associated with some embodiments;

[0017] Figure 6 is an exploded isometric view of another dressing that may be associated with an embodiment of the system of Figure 1, illustrating additional details that may be associated with some embodiments; and

[0018] Figure 7 is an exploded isometric view of yet another dressing that may be associated with an embodiment of the system of Figure 1, illustrating additional details that may be associated with some embodiments.

DESCRIPTION OF EXAMPLE EMBODIMENTS

[0019] The following description of example embodiments provides information that enables a person skilled in the art to make and use the subject matter set forth in the appended claims, but may omit certain details already well-known in the art. The following detailed description is, therefore, to be taken as illustrative and non-limiting.

[0020] Figure 1 is a block diagram of an example embodiment of a therapy system 100 that can provide negative-pressure therapy to a tissue site in accordance with this specification. The term “tissue site” in this context may refer to a wound, defect, or other treatment target located on or within tissue, including but not limited to, bone tissue, adipose tissue, muscle tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, or ligaments. A wound may include chronic, acute, traumatic, subacute, and dehisced wounds, partial-thickness bums, ulcers (such as diabetic, pressure, or venous insufficiency ulcers), flaps, grafts, and incisions, for example. The term “tissue site” may also refer to areas of any tissue that are not necessarily wounded or defective, but are instead areas in which it may be desirable to add or promote the growth of additional tissue. For example, negative pressure may be applied to a tissue site to grow additional tissue that may be harvested and transplanted.

[0021] The therapy system 100 may include a source or supply of reduced or negative pressure, such as a negative-pressure source 105, a dressing 110, a fluid container, such as a container 115, and a regulator or controller, such as a controller 120, for example. Additionally, the therapy system 100 may include sensors to measure operating parameters and provide feedback signals to the controller 120 indicative of the operating parameters. As illustrated in Figure 1, for example, the therapy system 100 may include one or more sensors coupled to the controller 120, such as a first sensor 125 and a second sensor 130. As illustrated in the example of Figure 1, the dressing 110 may include a tissue interface 135, a cover 140, or both in some embodiments. The dressing 110 may also be referred to as a dressing assembly in some examples, which may include additional or different features as described herein.

[0022] Some components of the therapy system 100 may be housed within or used in conjunction with other components, such as sensors, processing units, alarm indicators, memory, databases, software, display devices, or user interfaces that further facilitate therapy. For example, in some embodiments, the negative-pressure source 105 may be combined with the controller 120 and other components into a therapy unit.

[0023] In general, components of the therapy system 100 may be coupled directly or indirectly. For example, the negative-pressure source 105 may be directly coupled to the container 115, and may be indirectly coupled to the dressing 110 through the container 115. Coupling may include fluid, mechanical, thermal, electrical, or chemical coupling (such as a chemical bond), or some combination of coupling in some contexts. For example, the negative-pressure source 105 may be electrically coupled to the controller 120, and may be fluidly coupled to one or more distribution components to provide a fluid path to a tissue site. In some embodiments, components may also be coupled by virtue of physical proximity, being integral to a single structure, or being formed from the same piece of material.

[0024] A distribution component may be detachable, and may be disposable, reusable, or recyclable. The dressing 110 and the container 115 are illustrative of distribution components. A fluid conductor is another illustrative example of a distribution component. A “fluid conductor,” in this context, may include a tube, pipe, hose, conduit, or other structure with one or more lumina or open pathways adapted to convey a fluid between two ends. Typically, a tube is an elongated, cylindrical structure with some flexibility, but the geometry and rigidity may vary. Moreover, some fluid conductors may be molded into or otherwise integrally combined with other components. Distribution components may also include interfaces or fluid ports to facilitate coupling and de-coupling other components. In some embodiments, for example, a dressing interface may facilitate coupling a fluid conductor to the dressing 110. For example, such a dressing interface may be a SENSAT.R.A.C.™ Pad available from KCI of San Antonio, Texas.

[0025] A negative-pressure supply, such as the negative-pressure source 105, may be a reservoir of air at a reduced pressure, or may be a manual or electrically-powered device, such as a vacuum pump, a suction pump, a wall suction port available at many healthcare facilities, or a micropump, for example. “Negative pressure” or “reduced pressure” generally refers to a pressure less than a local ambient pressure, such as the ambient pressure in a local environment external to a sealed therapeutic environment. In many cases, the local ambient pressure may also be the atmospheric pressure at which a tissue site is located. Further, the pressure may be less than a hydrostatic pressure associated with tissue at the tissue site. Unless otherwise indicated, values of pressure stated herein are gauge pressures. References to increases in reduced pressure may refer to a decrease in absolute pressure, while decreases in reduced pressure may refer to an increase in absolute pressure. While the amount and nature of reduced pressure applied to a tissue site may vary according to therapeutic requirements, the pressure is generally a low vacuum, also commonly referred to as a rough vacuum, between -5 mm Hg (-667 Pa) and -500 mm Hg (-66.7 kPa). Common therapeutic ranges are between - 50 mm Hg (-6.7 kPa) and -300 mm Hg (-39.9 kPa). [0026] The container 115 is representative of a container, canister, pouch, or other storage component, which can be used to manage exudates and other fluids withdrawn from a tissue site. In many environments, a rigid container may be preferred or required for collecting, storing, and disposing of fluids. In other environments, fluids may be properly disposed of without rigid container storage, and a re-usable container could reduce waste and costs associated with negative-pressure therapy.

[0027] A controller, such as the controller 120, may be a microprocessor or computer programmed to operate one or more components of the therapy system 100, such as the negativepressure source 105. In some embodiments, for example, the controller 120 may be a microcontroller, which may include an integrated circuit containing a processor core and a memory programmed to directly or indirectly control one or more operating parameters of the therapy system 100. Operating parameters may include the power applied to the negative-pressure source 105, the pressure generated by the negative-pressure source 105, or the pressure distributed to the tissue interface 135, for example. The controller 120 may also be configured to receive one or more input signals, such as a feedback signal, and programmed to modify one or more operating parameters based on the input signals.

[0028] Sensors, such as the first sensor 125 and the second sensor 130, may be any apparatus operable to detect or measure a physical phenomenon or property, and generally provide a signal indicative of the phenomenon or property that is detected or measured. For example, the first sensor 125 and the second sensor 130 may be configured to measure one or more operating parameters of the therapy system 100. In some embodiments, the first sensor 125 may be a transducer configured to measure pressure in a pneumatic pathway and convert the measurement to a signal indicative of the pressure measured. In some embodiments, for example, the first sensor 125 may be a piezoresistive strain gauge. The second sensor 130 may optionally measure operating parameters of the negativepressure source 105, such as the voltage or current, in some embodiments. Signals from the first sensor 125 and the second sensor 130 may be suitable as an input signal to the controller 120, but some signal conditioning may be appropriate in some embodiments. For example, the signal may need to be filtered or amplified before it can be processed by the controller 120. Typically, the signal is an electrical signal, but may be represented in other forms, such as an optical signal.

[0029] The tissue interface 135 can be adapted to partially or fully contact a tissue site. The tissue interface 135 may take many forms, and may have many sizes, shapes, or thicknesses depending on a variety of factors, such as the type of treatment being implemented or the nature and size of a tissue site. For example, the size and shape of the tissue interface 135 may be adapted to the contours of deep and irregular shaped tissue sites. Moreover, any or all of the surfaces of the tissue interface 135 may have projections or an uneven, course, or jagged profile that can induce strains and stresses on a tissue site, which can promote granulation at the tissue site.

[0030] In some embodiments, the tissue interface 135 may be a manifold or may include a manifold and additional layers, components, or features, such as a tissue contact layer, depending on the desired treatment. A “manifold” in this context may include any substance or structure providing a plurality of pathways adapted to collect or distribute fluid relative to a tissue. For example, a manifold may be adapted to receive reduced pressure from a source and distribute reduced pressure through multiple apertures to or from a tissue site, which may have the effect of collecting fluid from a tissue site and drawing the fluid toward the source. In some embodiments, the fluid path may be reversed or a secondary fluid path may be provided to facilitate delivering or moving fluid relative to a tissue site.

[0031] In some illustrative embodiments, the pathways of a manifold may be interconnected to improve distribution or collection of fluids at a tissue site. In some illustrative embodiments, a manifold may be a porous foam material having interconnected cells or pores. For example, open-cell foam, porous tissue collections, and other porous material such as gauze or felted mat generally include pores, edges, and/or walls adapted to form interconnected fluid channels. Liquids, gels, and other foams may also include or be cured to include apertures and fluid pathways. In some embodiments, a manifold may additionally or alternatively include projections that form interconnected fluid pathways. For example, a manifold may be molded to provide surface projections that define interconnected fluid pathways.

[0032] The average pore size of foam may vary according to needs of a prescribed therapy. For example, in some embodiments, the tissue interface 135 may be foam having pore sizes in a range of 400-600 microns. The tensile strength of the tissue interface 135 may also vary according to needs of a prescribed therapy. For example, the tensile strength of foam may be increased for instillation of topical treatment solutions. In some examples, the tissue interface 135 may be reticulated polyurethane foam such as found in GRANUFOAM™ dressing or V.A.C. VERAFLO™ dressing, both available from KCI of San Antonio, Texas.

[0033] The tissue interface 135 may be either hydrophobic or hydrophilic. In an example in which the tissue interface 135 may be hydrophilic, the tissue interface 135 may also wick fluid away from a tissue site, while continuing to distribute negative pressure to the tissue site. The wicking properties of the tissue interface 135 may draw fluid away from a tissue site by capillary flow or other wicking mechanisms. An example of hydrophilic foam is a polyvinyl alcohol, open-cell foam such as V.A.C. WHITEFOAM™ dressing available from KCI of San Antonio, Texas. Other hydrophilic foams may include those made from polyether. Other foams that may exhibit hydrophilic characteristics include hydrophobic foams that have been treated or coated to provide hydrophilicity.

[0034] The tissue interface 135 may further promote granulation at a tissue site when pressure within the sealed therapeutic environment is reduced. For example, any or all of the surfaces of the tissue interface 135 may have an uneven, coarse, or jagged profile that can induce microstrain and stress at a tissue site if negative pressure is applied through the tissue interface 135.

[0035] In some embodiments, the tissue interface 135 may be constructed from bioresorbable materials. Suitable bioresorbable materials may include, without limitation, a polymeric blend of polylactic acid (PLA) and polyglycolic acid (PGA). The polymeric blend may also include without limitation polycarbonates, polyfumarates, and capralactones. The tissue interface 135 may further serve as a scaffold for new cell-growth, or a scaffold material may be used in conjunction with the tissue interface 135 to promote cell-growth. A scaffold is generally a substance or structure used to enhance or promote the growth of cells or formation of tissue, such as a three-dimensional porous structure that provides a template for cell growth. Illustrative examples of scaffold materials include calcium phosphate, collagen, PLA/PGA, coral hydroxy apatites, carbonates, or processed allograft materials.

[0036] Some embodiments of the tissue interface 135 may comprise layers, components, or features in addition to the manifold. For example, the tissue interface 135 of an absorptive dressing may comprise an absorbent layer, which may be characterized as exhibiting absorbency and/or as being adapted to absorb liquid (such as exudate) from the tissue site. In some embodiments, the absorbent layer may also be adapted to transfer negative pressure therethrough. In some embodiments, the absorbent layer may be configured to retain exudate and/or other fluids drawn from the tissue site during negative-pressure therapy, which may negate the necessity for separate fluid storage components such as an external fluid container. The absorbent layer may comprise any material capable of absorbing liquid (e.g. any absorbent material). In some embodiments, the absorbent layer may exhibit absorbency of at least 3 g saline/g, or at least 5 g saline/g, or from 8 to 20 g saline/g. In some embodiments, the absorbent layer may comprise superabsorbent material, such as superabsorbent polymer (SAP) particles or fibers. For example, some embodiments of the absorbent layer may comprise or consist essentially of one of the following: polyacrylate, sodium polyacrylate, polyacrylamide copolymer, ethylene-maleic anhydride copolymer, polyvinyl alcohol copolymer, cross-linked hydrophilic polymers, and combinations thereof. In some embodiments, the absorbent layer may be hydrophilic. In an example in which the absorbent layer is hydrophilic, the absorbent layer may also absorb or wick fluid away from one or more other components or layers of the dressing 110. In such an embodiment, the wicking properties of the absorbent layer may draw fluid away from one or more components or layers of the dressing 110 by capillary flow or other wicking mechanisms. An example of hydrophilic foam is a polyvinyl alcohol, open-cell foam. Other hydrophilic foams may include those made from polyether. Other foams that may exhibit hydrophilic characteristics include hydrophobic foams that have been treated or coated to provide hydrophilicity.

[0037] In some embodiments, the absorbent layer may have a bag-like structure for holding superabsorbent material. For example, the absorbent layer may be configured with superabsorbent material within a wicking pouch. In some embodiments, the pouch may comprise a first wicking layer and a second wicking layer. In some embodiments, the first wicking layer and the second wicking layer may be coupled around the pouch perimeter to form the enclosed pouch encapsulating (e.g. securely holding) the superabsorbent material to contain and prevent the superabsorbent material from migrating out of the pouch. For example, the first and second wicking layers may be coupled to each other using adhesive. The wicking layers may each comprise wicking material. The wicking material may be configured to be permeable to liquid (such as exudate), while retaining the superabsorbent material within the pouch. For example, the porosity of the wicking layers may be sufficiently small to prevent migration of the superabsorbent material through the wicking layers. The wicking layers may be configured to wick liquid along the superabsorbent material in a lateral direction normal to a thickness of the superabsorbent material within the pouch. Wicking of liquid laterally may enhance the distribution of liquid to the superabsorbent material, which may in turn speed absorption and/or allow for the superabsorbent material to maximize its absorbency. Examples of the wicking material may comprise or consist essentially of one of the following: Viscose, PET, Lidro™ non-woven material, a knitted polyester woven textile material, such as the one sold under the name InterDry® AG material from Coloplast A/S of Denmark, GORTEX® material, DuPont Softesse® material, etc., and combinations thereof. In some embodiments, the absorbent layer may serve as the manifold. For example, the absorbent layer may have manifolding properties, such that a separate manifold may not be necessary for negative-pressure therapy.

[0038] Some embodiments of the tissue interface 135 may comprise a protective layer (e.g. a tissue-contact layer). In some embodiments, the protective layer may act as a comfort layer, configured to improve comfort at the tissue site. In some embodiments, the protective layer may act as a fluid control layer, configured to minimize maceration, backflow of exudate out of the dressing to the tissue site, and/or tissue in-growth from the tissue site into the dressing 110. The protective layer may be configured to allow fluid transport from the tissue site into the dressing 110 and/or to manifold during negative-pressure therapy. In some embodiments, the protective layer may be configured as the tissuecontact surface for the dressing, so that in use it may be located adjacent to and/or direct contact with the tissue site. In some embodiments, the protective layer may be located between the tissue-contact surface and the manifold and/or the absorbent layer. In some embodiments, the protective layer may be located between the tissue site (when the dressing is in use) and the manifold and/or absorbent layer.

[0039] In some embodiments, the protective layer may comprise a porous fabric, a porous film, or a polymeric film (e.g. which may be liquid impermeable) with a plurality of fluid passages (e.g. slits, slots, or fluid valves). In some embodiments, the protective layer may comprise or consist essentially of a woven, elastic material or a polyester knit textile substrate. As a non-limiting example, an InterDry™ textile material from Milliken Chemical of Spartanburg, South Carolina, may be used. The protective layer may also include anti -microbial substances, such as silver, in some embodiments.

[0040] In some embodiments, the protective layer may comprise or consist essentially of a liquid-impermeable, elastomeric material. For example, the protective layer may comprise or consist essentially of a polymer film. In some embodiments, for example, the protective layer may comprise or consist essentially of a hydrophobic polymer, such as a polyethylene film. The simple and inert structure of polyethylene can provide a surface that interacts little, if any, with biological tissues and fluids, providing a surface that may encourage the free flow of liquids and low adherence, which can be particularly advantageous for many applications. Other suitable polymeric films include polyurethanes, acrylics, polyolefin (such as cyclic olefin copolymers), polyacetates, polyamides, polyesters, copolyesters, PEBAX block copolymers, thermoplastic elastomers, thermoplastic vulcanizates, polyethers, polyvinyl alcohols, polypropylene, polymethylpentene, polycarbonate, styreneics, silicones, fluoropolymers, and acetates. A thickness between 20 microns and 100 microns may be suitable for many applications. In some embodiments, the protective layer may be hydrophobic. In some embodiments, the protective layer may be hydrophilic. In some embodiments, the protective layer may be suitable for coupling, such as welding, to other layers, such as the manifold.

[0041] Some embodiments of the protective layer may have one or more fluid passages, which can be distributed uniformly or randomly across the protective layer. The fluid passages may be bidirectional and pressure-responsive. For example, each of the fluid passages generally may comprise or consist essentially of an elastic passage that is normally unstrained to substantially reduce liquid flow, and can expand or open in response to a pressure gradient. In some embodiments, the fluid passage may comprise or consist essentially of perforations in the protective layer. Perforations may be formed by removing material from the protective layer. For example, perforations may be formed by cutting through the protective layer, which may also deform the edges of the perforations in some embodiments. In the absence of a pressure gradient across the perforations, the passages may be sufficiently small to form a seal or fluid restriction, which can substantially reduce or prevent liquid flow. Additionally or alternatively, one or more of the fluid passages may be an elastomeric valve that is normally closed when unstrained to substantially prevent liquid flow, and can open in response to a pressure gradient. A fenestration may be a suitable valve for some applications. Fenestrations may also be formed by removing material from the protective layer, but the amount of material removed and the resulting dimensions of the fenestrations may be up to an order of magnitude less than perforations, and may not deform the edges.

[0042] For example, some embodiments of the fluid passages may comprise or consist essentially of one or more slits, slots or combinations of slits and slots in the protective layer. In some examples, the fluid passages may comprise or consist of linear slots having a length less than 4 millimeters and a width less than 1 millimeter. The length may be at least 2 millimeters, and the width may be at least 0.4 millimeters in some embodiments. A length of about 3 millimeters and a width of about 0.8 millimeters may be particularly suitable for many applications, and a tolerance of about 0. 1 millimeter may also be acceptable. Such dimensions and tolerances may be achieved with a laser cutter, for example. Slots of such configurations may function as imperfect valves that substantially reduce liquid flow in a normally closed or resting state. For example, such slots may form a flow restriction without being completely closed or sealed. The slots can expand or open wider in response to a pressure gradient to allow increased liquid flow.

[0043] In some embodiments, the cover 140 may provide a bacterial barrier and protection from physical trauma. The cover 140 may also be constructed from a material that can reduce evaporative losses and provide a fluid seal between two components or two environments, such as between a therapeutic environment and a local external environment. For example, the cover 140 may comprise or consist essentially of an elastomeric film or membrane that can provide a seal adequate to maintain a reduced pressure at a tissue site for a given negative-pressure source. In some example embodiments, the cover 140 may be a polymer drape, such as a polyurethane fdm, that is permeable to water vapor but impermeable to liquid. The cover 140 may have a high moisture-vapor transmission rate (MVTR) in some applications. For example, the MVTR may be at least 250 g/m^A2 per twenty- four hours in some embodiments (based on ASTM E96/E96M for upright cup measurement, e.g. at 38 degrees Celsius and 10% relative humidity). In some embodiments, an MVTR up to 2600 grams per square meter per twenty-four hours or up to 5,000 grams per square meter per twenty-four hours may provide effective breathability and mechanical properties. Such drapes typically have a thickness in the range of 25-50 microns. For permeable materials, the permeability generally should be low enough that a desired negative pressure may be maintained. In some embodiments, the cover 140 may form an outer surface of the dressing 110.

[0044] The cover 140 may comprise, for example, one or more of the following materials: polyurethane (PU), such as hydrophilic polyurethane; cellulosics; hydrophilic polyamides; polyvinyl alcohol; polyvinyl pyrrolidone; hydrophilic acrylics; silicones, such as hydrophilic silicone elastomers; an INSPIRE 2301 and INSPIRE 2327 material from Coveris Advanced Coatings of Wrexham, United Kingdom having, for example, an MVTR (inverted cup technique) of 14400 g/m2/24 hours and a thickness of about 30 microns; a thin, uncoated polymer drape; natural rubbers; polyisoprene; styrene butadiene rubber; chloroprene rubber; polybutadiene; nitrile rubber; butyl rubber; ethylene propylene rubber; ethylene propylene diene monomer; chlorosulfonated polyethylene; polysulfide rubber; ethylene vinyl acetate (EVA); EVA film; co-polyester; a silicone drape; a 3M Tegaderm® drape; a polyurethane (PU) drape such as one available from Avery Dennison Corporation of Glendale, California; polyether block polyamide copolymer (PEBAX), for example, from Arkema, France; INSPIRE 2327; or other appropriate material.

[0045] An attachment device may be used to attach the cover 140 to an attachment surface, such as undamaged epidermis, a gasket, or another cover (e .g . at the tissue site) . The attachment device may take many forms. For example, an attachment device may be a medically-acceptable, pressuresensitive adhesive configured to bond the cover 140 to epidermis around a tissue site. In some embodiments, for example, some or all of the cover 140 may be coated with an adhesive, such as an acrylic adhesive, which may have a coating weight between 25-65 grams per square meter (g.s.m.). Thicker adhesives, or combinations of adhesives, may be applied in some embodiments to improve the seal and reduce leaks. Other example embodiments of an attachment device may include a doublesided tape, paste, hydrocolloid, hydrogel, silicone gel, or organogel.

[0046] Figure 2 is a graph illustrating additional details of an example control mode that may be associated with some embodiments of the controller 120. In some embodiments, the controller 120 may have a continuous pressure mode, in which the negative-pressure source 105 is operated to provide a constant target reduced pressure, as indicated by line 205 and line 210, for the duration of treatment or until manually deactivated. Additionally or alternatively, the controller may have an intermittent pressure mode, as illustrated in the example of Figure 2. In Figure 2, the x-axis represents time, and the y-axis represents reduced pressure generated by the negative-pressure source 105 over time. In the example of Figure 2, the controller 120 can operate the negative-pressure source 105 to cycle between a target pressure and atmospheric pressure. For example, the target pressure may be set at a value of 125 mmHg, as indicated by line 205, for a specified period of time (e.g., 5 min), followed by a specified period of time (e.g., 2 min) of deactivation, as indicated by the gap between the solid lines 215 and 220. The cycle can be repeated by activating the negative-pressure source 105, as indicated by line 220, which can form a square wave pattern between the target pressure and atmospheric pressure.

[0047] In some example embodiments, the increase in negative-pressure from ambient pressure to the target pressure may not be instantaneous. For example, the negative-pressure source 105 and the dressing 110 may have an initial rise time, as indicated by the dashed line 225. The initial rise time may vary depending on the type of dressing and therapy equipment being used. For example, the initial rise time for one therapy system may be in a range of about 20-30 mmHg/second and in a range of about 5-10 mmHg/second for another therapy system. If the therapy system 100 is operating in an intermittent mode, the repeating rise time as indicated by the solid line 220 may be a value substantially equal to the initial rise time as indicated by the dashed line 225.

[0048] Figure 3 is a graph illustrating additional details that may be associated with another example pressure control mode in some embodiments of the therapy system 100. In Figure 3, the x- axis represents time and the y-axis represents negative pressure generated by the negative-pressure source 105. The target pressure in the example of Figure 3 can vary with time in a dynamic pressure mode . For example, the target pressure may vary in the form of a triangular waveform, varying between a minimum and maximum reduced pressure of 50-125 mmHg with a rise time 305 set at a rate of +25 mmHg/min. and a descent time 310 set at -25 mmHg/min, respectively. In other embodiments of the therapy system 100, the triangular waveform may vary between reduced pressure of 25-125 mmHg with a rise time 305 set at a rate of +30 mmHg/min and a descent time 310 set at -30 mmHg/min.

[0049] In some embodiments, the controller 120 may control or determine a variable target pressure in a dynamic pressure mode, and the variable target pressure may vary between a maximum and minimum pressure value that may be set as an input prescribed by an operator as the range of desired reduced pressure. The variable target pressure may also be processed and controlled by the controller 120, which can vary the target pressure according to a predetermined waveform, such as a triangular waveform, a sine waveform, or a saw-tooth waveform. In some embodiments, the waveform may be set by an operator as the predetermined or time-varying reduced pressure desired for therapy.

[0050] Referring to Figures 4-5, the dressing 110 may include features that can treat a tissue site, or parts thereof, and an area of tissue around the tissue/treatment site. For example, the tissue site may be an incision or other treatment target on a patient. The dressing 110 may be configured to treat not only the incision or treatment target, but also, an area of tissue around the incision or treatment target. While the figures may illustrate exemplary dressing embodiments with a particular longitudinal shape, other exemplary dressings may have other sizes, shapes, and/or configurations, for example for use on other tissue sites.

[0051] Figure 4 is an exploded, isometric view of an example embodiment of a dressing or dressing assemblage that may be associated with an example embodiment of the therapy system of Figure 1. Referring more specifically to Figure 4, in some examples, the dressing 110 may include an attachment device 404, a manifold 406, and the cover 140. Some examples of the attachment device 404 and other components may include a treatment aperture 408, and the manifold 406 may be configured to be at least partially exposed to a tissue site through the treatment aperture 408. Further, in some examples, the dressing 110 may optionally include an adhesive ring 410 that may be configured to bond a peripheral portion of the manifold 406 to a portion of the attachment device 404. In some examples, the adhesive ring 410 may be formed as part of the attachment device 404, or the adhesive ring 410 may be omitted with the attachment device 404 instead being coupled to the manifold 406 and/or cover 140 with another medically acceptable coupling apparatus. In some examples, the cover 140, the manifold 406, the optional adhesive ring 410, and the attachment device 404 may have similar shapes. The attachment device 404 may be slightly larger than the manifold 406 to permit coupling of the attachment device 404 to the cover 140 around the manifold 406. In some examples, an adhesive may be disposed on a portion of the manifold 406 exposed through the treatment aperture 408. In some embodiments, the adhesive may be pattern-coated, and may cover up to 50% of the exposed portion or surface of the manifold 406.

[0052] The cover 140, the manifold 406, the attachment device 404, or various combinations may be assembled, for example forming a pre-assembled dressing assemblage, before application to or at a tissue site. In some embodiments, the dressing 110 (or dressing assemblage) may be provided as a single unit.

[0053] The manifold 406 may include a first surface 414 and an opposing second surface 412. In some examples, at least a portion of the first surface 414 (e.g. the tissue-facing surface) of the manifold 406 may be configured to face the tissue site (e.g. the area of tissue around the extremity) through the treatment aperture 408. In some examples, the attachment device 404 may be positioned on or at a portion of the first surface 414 of the manifold 406. In some examples, the manifold 406 may include or be formed of a porous material, such as foam.

[0054] In some examples, the attachment device 404 may be configured to create a sealed space between the cover 140 and the tissue site, and the manifold 406 may be configured to be positioned in the sealed space. For example, the attachment device 404 may be positioned around an edge 416 of the manifold 406 and configured to surround the tissue site. The cover 140 may be disposed over the manifold 406 and coupled to the attachment device 404 around the manifold 406. For example, the cover 140 may be coupled to a portion of the attachment device 404 extending outward from the edge 416 of the manifold 406. Further, the cover 140 may be larger than the manifold 406, as illustrated in the example of Figure 4, and may have a perimeter or a flange 418 configured to be attached to the atachment device 404. Assembled, the cover 140 may be disposed over the second surface 412 (e.g. the outward-facing surface) of the manifold 406, and the flange 418 may be atached to the atachment device 404 around the manifold 406. For example, an adhesive may be used to adhere the flange 418 to the atachment device 404, or the flange 418 may be, without limitation, welded, stitched, or stapled to the atachment device 404. In some embodiments, the attachment device may comprise an adhesive applied to the flange 418 and configured to allow atachment of the flange 418 to the tissue site and/or to a drape on the tissue site. The cover 140 may also include a port 420 configured to allow fluid communication between the manifold 404 and a dressing interface 422 and/or a fluid conductor 424 (e.g. to apply negative pressure under the cover) as described herein.

[0055] The atachment device 404 may take many forms. In some examples, the atachment device 404 may include or be formed of a film or membrane that can provide a seal in a therapeutic negative-pressure environment. In some example embodiments, the attachment device 404 may be a polymer film, such as a polyurethane film, that is permeable to water vapor but impermeable to liquid. The attachment device 404 may have a thickness in the range of 25-50 microns. For permeable materials, the permeability may be low enough that a desired reduced pressure may be maintained. The atachment device 404 may also include a medically-acceptable adhesive, such as a pressure -sensitive adhesive. In examples, the atachment device 404 may be a polymer film coated with an adhesive, such as an acrylic adhesive, which may have a coating weight between 25-65 grams per square meter (g.s.m.). Thicker adhesives, or combinations of adhesives, may be applied in some examples to improve the seal and reduce leaks.

[0056] In some examples, the attachment device 404 may include or be formed of a hydrocolloid. In some examples, the attachment device 404 may be configured or referred to as a sealing ring or a gasket member. In other examples, the dressing 110 may include a gasket member (not shown) in addition to the attachment device 404. In such an example, the gasket member may be a peripheral member, such as a hydrocolloid ring, and at least a portion of the atachment device 404 may be positioned between the manifold 406 and the gasket member on or at a surface of the manifold 406, such as the first surface 414, configured to face the area of tissue around the tissue site. In some examples, the gasket member may have a similar or analogous shape as the adhesive ring 410, but the gasket member may be positioned on a surface of the atachment device 404 configured to face the tissue site such that the gasket member is configured to be positioned between the tissue site and the atachment device 404.

[0057] In some examples, the dressing 110 may optionally further include a protective layer 425, which may be coupled to a surface of the manifold 406, such as the first surface 414, and may be configured to be exposed to the tissue site. In some embodiments, the protective layer 425 may be configured to be positioned in direct contact with the tissue site, for example forming a tissue-contact surface. In other embodiments (e.g. without a protective layer), the tissue-contact surface may be formed by the manifold and/or the atachment device. The protective layer 425 may include or be formed of a material that substantially reduces or eliminates skin irritation while allowing fluid transfer through the protective layer. In some embodiments, the protective layer 425 may form a fluid control layer, configured to allow fluid communication between the tissue site and the manifold during negative-pressure therapy, while minimizing backflow of fluids (such as exudate) from the manifold to the tissue site (e.g. to minimize maceration). In some examples, the protective layer 425 may include or be formed of one or more of the following materials, without limitation: a woven material, a nonwoven material, a polyester knit material, and a fenestrated film.

[0058] In some examples, the attachment device 404, which may comprise an adhesive on a surface of the dressing 110 configured to face the tissue site (e.g. on the tissue-contact surface), may be covered by one or more release liners 428 prior to applying the dressing 110 at the tissue site. For example, as shown in Figure 4, the dressing 110 may include a first release liner 428a, a second release liner 428b, and a third release liner 428c. The first release liner 428a may be positioned proximate to a first side 430 of the manifold 406 or the dressing 110, the second release liner 428b may be positioned proximate to a second side 432 of the manifold 406 or the dressing 110 (e.g. with the first side 430 and the second side 432 opposite each other across a line of symmetry), and the third release liner 428c may be positioned proximate to a fold axis, centerline, or line or symmetry of the manifold 406 or the dressing 110 (e.g. spanning a central portion of the manifold and/or dressing). The central portion with the line of symmetry may be located between the first side 430 and the second side 432, and the third release liner 428c may be positioned between the first release liner 428a and the second release liner 428b. In some examples, the third release liner 428c may be configured to be removed to expose an adhesive or portion of the attachment device 404 proximate to the line of symmetry prior to removal of the first release liner 428a and the second release liner 428b. Such a configuration may permit the central portion of the dressing 110 (e.g. in proximity to the line of symmetry) to be initially positioned or aligned at a tissue site, such as the extremity, while the first release liner 428a and the second release liner 428b protect other portions of the adhesive or the attachment device 404. For example, a portion of the third release liner 428c may cover or be positioned over a portion of the first release liner 428a and/or the second release liner 428b such that the third release liner 428c may be removed prior to removal of the first release liner 428a and the second release liner 428b. In some examples, the dressing 110 may have two release liners, each of which may have perforations or slits (not shown here) configured to allow the release liners to be separated into smaller pieces for removal. Additionally, some embodiments may also have one or more casting sheet liners 436.

[0059] Additionally or alternatively, the first release liner 428a, the second release liner 428b, and the third release liner 428c may provide stiffness to the attachment device 404 to facilitate handling and application. Additionally or alternatively, the casting sheet liners 436 may cover the flange 418 to provide stiffness to the cover 140 for handling and application. The one or more release liner 428 may be configured to releasably cover the attachment device 404, for example to protect and maintain the adhesive of the attachment device 404 until the time of application of the dressing 110 to the tissue site. [0060] Figure 5 is a schematic view illustrating an exemplary system 100 including a simplified example of the dressing 110 in place on an exemplary tissue site 505, illustrating additional details that may be associated with some embodiments. The system 100 may comprise a negativepressure source 105 in fluid communication with the dressing 110. For example, the dressing 110 may comprise a dressing interface 422, which may penetrate or fluidly couple with the dressing 110 through the port 420 in the cover 140 to fluidly couple to the manifold 406 of the dressing 110. In some embodiments, a fluid conductor 424 may fluidly couple the negative-pressure source 105 to the dressing interface 422 (thereby fluidly coupling the negative -pressure source 105 to the manifold 406 of the dressing 110, for application of negative-pressure therapy to the tissue site 505 through the manifold 406 of the dressing 110).

[0061] In operation, the negative-pressure source 105 can reduce pressure in the sealed therapeutic environment (e.g. when the dressing 110 is applied to the tissue site 505 in the usage configuration). Reduced pressure applied to the tissue site 505 through the manifold 406 in the sealed therapeutic environment can induce macro-strain and/or micro-strain in the tissue site, as well as remove exudates and other fluids from the tissue site 505, which can be collected in the container 115.

[0062] In general, exudates and other fluids flow toward lower pressure along a fluid path. Thus, the term “downstream” may refer to a location in a fluid path relatively closer to a source of reduced pressure or further away from a source of positive pressure. Conversely, the term “upstream” may refer to a location further away from a source of reduced pressure or closer to a source of positive pressure.

[0063] In some example embodiments, the controller 120 may receive and process data from one or more sensors, such as the first sensor 125. The controller 120 may also control the operation of one or more components of the therapy system 100 to manage the pressure delivered to the tissue interface 135, such as the manifold 406 and associated components. In some embodiments, the controller 120 may include an input for receiving a desired target pressure, and may be programmed for processing data relating to the setting and inputting of the target pressure to be applied to the tissue interface 135. In some example embodiments, the target pressure may be a fixed pressure value set by an operator as the target reduced pressure desired for therapy at a tissue site and then provided as input to the controller 120. The target pressure may vary from tissue site to tissue site based on the type of tissue forming a tissue site, the type of injury or wound (if any), the medical condition of the patient, and the preference of the attending physician. After selecting a desired target pressure, the controller 120 can operate the negative-pressure source 105 in one or more control modes based on the target pressure, and may receive feedback from one or more sensors to maintain the target pressure at the tissue interface 135. In some embodiments, the manifold 406 may have distinct pressure zones, and different target pressures and control modes may be applied to different pressure zones.

[0064] Figure 6 is an exploded isometric view of another dressing, illustrating additional details that may be associated with some embodiments. The dressing 110 in Figure 6 may comprise a drape 605 having integral support. For example, the drape 605 may have an integral, semi-rigid support layer 610. The support layer 610 may be configured to provide sufficient support so that the drape 605 is self-supporting. For example, the drape 605 may be configured to be self-supporting prior to application of the dressing 110 to the tissue site, and may be configured to allow application of the drape 605 to the tissue site. In some embodiments, the support layer 610 may be sufficiently rigid to render the drape 605 self-supporting (e.g. not likely to fold over onto itself due to its own weight and/or sufficiently rigid so that the edges will not substantially droop, for example so that the edges hang down less than 90 degrees, less than 45 degrees, less than 20 degrees, or less than 10 degrees, under its own weight), but sufficiently flexible, pliable, conformable, and/or malleable to allow the drape 605 to be applied and close coupled to the tissue site (e.g. which may involve curvature). In some embodiments, the support layer 610 may be sufficiently rigid to maintain the dressing approximately within a flat plane under its own weight (e.g. so that additional force, for example applied by a user’s hand, would have to be applied to bend the drape substantially out of the flat plane). In some embodiments, the support layer 610 may have a stiffness similar to (e.g. approximately the same as) or greater than (for example, by +5%, +10%, or +20%) that of 78# casting paper. For example, the support layer 610 may comprise material having a Young’s Modulus of approximately 0.1 - lOGPa and a thickness of about 0.01 inch or less. In some embodiments, the Young’s Modulus may be higher, for example up to 100 GPa, for a thinner support layer. In some embodiments, the support layer 610 may be configured so that, when the drape 605 is applied to the tissue site, substantially no forces are introduced to the tissue site due to elasticity of the support layer 610. In some embodiments, the support layer 610 may be configured to be left in place when the dressing or drape 605 is attached to the tissue site and in use, for example with the integral support layer 610 being permanently attached to and non-removable from the drape 605 (e.g. the support layer 610 cannot be removed from the drape 605 without significantly damaging the drape 605). In some embodiments, the support layer 610 may be configured within the drape 605 so as to not be visible (e.g. covered on all sides, so that an end-user cannot discern the support layer 610 merely by visual inspection of the drape 605).

[0065] In some embodiments, the drape 605 may be configured to seal the tissue site for negative-pressure therapy. For example, the drape 605 may comprise a material similar to the cover 140. In some embodiments, the support layer 610 may be embedded within the drape 605. For example, the support layer 610 may be internal to the drape 605. In some embodiments, the support layer 610 may be configured to support the drape 605 substantially around a perimeter of the drape 605, for example only directly providing support around the perimeter without directly supporting the central portion of the drape 605. For example, the support layer 610 may comprise an interior aperture 625, and in some embodiments the support layer 610 around the interior aperture 625 may span the perimeter of the drape 605 (e.g. be positioned around only the perimeter of the drape). In some embodiments, the interior aperture 625 may span a majority of the surface area of the support layer 610, leaving only a narrow perimeter border of support. In some embodiments, the perimeter of the drape 605 may be supported for a border width w of approximately 1/8 - % inch (and within this approximately 1/8 - % inch wide border around the perimeter, may lie the interior aperture 625).

[0066] In some embodiments, the dressing 110 may further comprise: an attachment device 404 having a treatment aperture 408; a manifold 406 configured to be at least partially exposed to the tissue site through the treatment aperture 408; and a cover 140 configured to be disposed over the manifold 406 and coupled to the attachment device 404 around the manifold 406. In some embodiments, the cover 140 may comprise a flange 418 extending beyond the manifold 406. In some embodiments, the attachment device 404, manifold 406, and/or cover 140 may be pre-assembled (e.g. coupled) to form a single unit, such as a dressing assemblage 670, which may be similar to the dressing shown in Figure 4. In some embodiments, the drape 605 may be attached to the dressing assemblage 670, forming a single, integral dressing 110 unit. In some embodiments, the drape 605 may be separate but configured for use with the dressing assemblage 670, for example with the drape 605 configured to be applied to the tissue site, and the dressing assembly configured to be applied over the drape 605 in fluid communication with the tissue site through the drape 605 (e.g. through one or more apertures in the drape 605). In some embodiments, the interior aperture 625 of the support layer 610 may be larger than the treatment aperture 408 of the dressing assemblage 670.

[0067] In some embodiments, the drape 605 may further comprise an outer drape layer 615 and a base drape layer 620, with the support layer 610 located therebetween. For example, the support layer 610 may be stacked between and in contact with the outer drape layer 615 and the base drape layer 620. In some embodiments, the outer drape layer 615 may comprise an interface aperture 630, the base drape layer 620 may comprise a base aperture 635, and the interface aperture 630 and the base aperture 635 may be vertically aligned with each other and with the interior aperture 625 of the support layer 610. For example, the interface aperture 630, the interior aperture 625, and the base aperture 635 may all be centered on a common central axis (e.g. extending orthogonal to the drape layers), may be coaxial, and/or may be concentric.

[0068] In some embodiments, the interface aperture 630 may be configured to interface with the treatment aperture 408 of the dressing assemblage 670. For example, the interface aperture 630 of the outer drape layer 615 may be configured to fluidly communicate with the treatment aperture 408 (and therethrough to the manifold 406). In some embodiments, the interface aperture 630 may be configured to fluidly communicate with the interior aperture 625 of the support layer 610, and thereby to the base aperture 635 (leading to the tissue site). In some embodiments, the interface aperture 630 may be configured to fluidly couple the treatment aperture 408 to the interior aperture 625, and the interior aperture 625 may be configured to fluidly couple the interface aperture 630 to the base aperture 635 (and thereby to the tissue site).

[0069] In some embodiments, the interface aperture 630 may be approximately the size of the treatment aperture 408. In some embodiments, the interface aperture 630 may be sized to be smaller than the flange 418 of the cover 140 (e.g. the flange 418 of the cover may extend beyond the interface aperture 630 when coupled). In some embodiments, the interface aperture 630 may be smaller than the interior aperture 625 of the support layer 610. In some embodiments, the base aperture 635 may be approximately the same size as the interior aperture 625 of the support layer 610. In the embodiments, the perimeter of the outer drape layer 615, the support layer 610, and the base drape layer 620 may all be approximately the same size and/or stacked in alignment (e.g. so that the outer edges of the drape layers all approximately match, align, and/or are flush).

[0070] In some embodiments, the support layer 610 may be stacked or sandwiched between and coupled to both the outer drape layer 615 and the base drape layer 620. For example, the support layer 610 may be adhered or otherwise bonded (e.g. heat bonded or welded) to both the outer drape layer 615 and the base drape layer 620. In some embodiments, the base drape layer 620 may be adhesive on a surface (e.g. a contact surface 650, configured to contact the tissue site) opposite the support layer 610. For example, the outer drape layer 615 may comprise a first surface 640, configured to face towards and/or contact the support layer 610, and a second surface 645 opposite the first surface 640, with the first surface 640 being adhesive (e.g. the first surface 640 of the outer drape layer 615 may comprise a first adhesive) and the second surface 645 of the outer drape layer 615 not being adhesive. In some embodiments, the base drape layer 620 may comprise a contact surface 650 configured to contact the tissue site and an exterior surface 655 opposite the contact surface 650 (e.g. configured to contact the support layer 610), with both the contact surface 650 and the exterior surface 655 being adhesive (e.g. the contact surface 650 may comprise a second adhesive and the exterior surface 655 may comprise athird adhesive). In some embodiments, the second adhesive (e.g. on the contact surface 650) may be configured to sealing and removably attach the dressing 110 or drape 605 to the tissue site. For example, the second adhesive may comprise or consist essentially of one or more of the following: acrylic and hydrocolloid. In some embodiments, the first adhesive and the third adhesive (e.g. the adhesives contacting the support layer 610) may be configured to securely and/or permanently attach the drape layers to the support layer 610. For example, the first and third adhesives may each comprise or consist essentially of one or more of the following: acrylate, acrylate double-sided adhesive, and 3M™ Double Coated Medical Tape Product Number 1522. In some embodiments, the first adhesive and the third adhesive may be the same, while in other embodiments they may differ.

[0071] In some embodiments, substantially the entire base drape layer 620 may be adhered to substantially the entire support layer 610. In some embodiments, the base drape layer 620 may be approximately the same size as the support layer 610. In some embodiments, only a perimeter of the outer drape layer 615 may be adhered to the support layer 610 (e .g . an interior portion of the outer drape layer 615 may not contact or adhere to the support layer 610). In some embodiments, the support layer 610 and/or the base drape layer 620 may support the perimeter of the drape 605 by extending in from the perimeter for a border width w of approximately 1/8 - % inch. In some embodiments, the border width w may be approximately uniform about the entire perimeter, while in other embodiments, the border width w may vary within the range of approximately 1/8 - % inch along the perimeter. In some embodiments, the outer drape layer 615, the support layer 610, and the base drape layer 620 may be pre-formed as an integral drape 605 unit (with integral support).

[0072] In some embodiments, the outer drape layer 615 and/or the base drape layer 620 may be similar to the cover 140 in Figure 4, for example comprising or consisting essentially of similar materials and/or having similar thickness . For example, the outer drape layer 615 and/or the base drape layer 620 may comprise or consist essentially of a polymer fdm, such as one or more of the following: polyurethane (PU), such as hydrophilic polyurethane; cellulosics; hydrophilic polyamides; polyvinyl alcohol; polyvinyl pyrrolidone; hydrophilic acrylics; silicones, such as hydrophilic silicone elastomers; natural rubbers; polyisoprene; styrene butadiene rubber; chloroprene rubber; polybutadiene; nitrile rubber; butyl rubber; ethylene propylene rubber; ethylene propylene diene monomer; chlorosulfonated polyethylene; polysulfide rubber; ethylene vinyl acetate (EVA); co-polyester; polyether block polyamide copolymer (PEBAX); or other appropriate material. In some embodiments, the outer drape layer 615 and/or the base drape layer 620 may have a thickness of approximately 25-50 microns, for example approximately 30 microns. In some embodiments, the outer drape layer 615 and/or the base drape layer 620 may have a thickness of about 3 mil, about 3-5 mil, or less than about 5 mil. In some embodiments, the outer drape layer 615 and/or the base drape layer 620 may have a high MVTR, such as at least 250, at least 2600, at least 5000, 250 - 5000, 250 - 2600, or 2600-5000 grams per square meter per twenty-four hours.

[0073] In some embodiments, the support layer 610 may comprise a polymer fdm, which may be thicker and/or stiffer (e.g. formed of a stiffer material) than the outer drape layer 615 and/or the base drape layer 620. For example, the support layer 610 may comprise or consist essentially of a polyurethane (PU) fdm, which may be approximately 0.01 inch thick. In some embodiments, the support layer 610 may comprise or consist essentially of a polycarbonate fdm. In some embodiments, the support layer 610 may have a thickness that is approximately an order of magnitude greater than the thickness of the outer drape layer 615 and/or the base drape layer 620. In some embodiments, the support layer 610 may have a thickness of about 0.01 inch or less. In some embodiments, the support layer 610 may be configured to have an MVTR similar to the cover 140 and/or outer drape layer 615, and the similar MVTR may be either due to material property (e.g. porosity) of the support layer 610 or perforations 660 in the support layer 610 configured to provide the MVTR. For example, if the polymer fdm material forming the support layer 610 has a low MVTR (or a lower MVTR than the outer drape layer 615), the support layer 610 may comprise a plurality of perforations 660 in the fdm material which may be configured to provide MVTR similar to the cover 140 and/or outer drape layer 615. For example, each of the perforations 660 may have a diameter of approximately 2-5 mm, and the total exposed area (e.g. area of the support layer without support material) may be approximately 20-40%. In some embodiments, the support layer 610 may comprise or consist essentially of a mesh, such as a semi-rigid mesh. In some embodiments, the mesh of the support layer 610 may be formed by interwoven strands of material, such as a polymer (e.g. PU or polycarbonate) or carbon fiber. In some embodiments, the mesh of the support layer 610 may be formed by a plurality of perforations 660 in a polymer sheet or film. In some embodiments, the support layer 610 may comprise a polymer film embedded with carbon fibers. In some embodiments, the carbon fibers may form a mesh (e.g. located within the polymer film). For example, the carbon fibers may be formed into a fabric (e.g. woven) sheet that is located within the film, and the fabric may be located in proximity to a central plane of film. In some embodiments, the mesh of carbon fiber strands may comprise weft and warp strands (e.g. a grid) that are approximately orthogonal. In some embodiments, the support layer 610 may comprise a PU film with carbon fibers. In some embodiments, the support layer 610 may comprise a polycarbonate film with carbon fibers. In some embodiments, the carbon fibers may form approximately 2-5% of the support layer 610.

[0074] Figure 7 is an exploded isometric view of yet another dressing, illustrating additional details that may be associated with some embodiments. In some embodiments, the outer drape layer 615 or the drape 605 as a whole may be or serve as a cover 140 (e.g. for a dressing 110). For example, the outer drape layer 615 or the drape 605 as a whole may form a solid sheet or film without any aperture or opening, which is configured to seal a tissue site for negative-pressure therapy. For example, such an outer drape layer 615 may be configured for use over a manifold 406. In some embodiments, a dressing interface 422 may be coupled to the second surface 645 of the outer drape layer 615, for example to provide negative pressure to a manifold 406 located thereunder.

[0075] The embodiment shown in Figure 7 may be similar to the embodiment shown in Figure 6, except that the cover 140 may form and/or comprise the outer drape layer 615 (e.g. the outer drape layer 615 of the drape 605 may form the cover 140). For example, a portion of the cover 140 (e.g. the portion of the cover 140 not disposed over the manifold 406 and/or which extends beyond the manifold 406) may form the outer drape layer 615. In some embodiments, the cover 140 may comprise a flange 418 extending outward beyond a perimeter of the manifold 406, and the flange 418 of the cover 140 may form the outer drape layer 615. In some embodiments, a separate attachment device 404 may not be necessary. For example, the drape 605 may function as the attachment device 404 (e.g. for attaching the manifold 406 to the tissue site and allowing fluid communication between the manifold 406 and the tissue site). By way of example, the adhesive on the contact surface 650 of the base drape layer 620 may be configured to attach the dressing to the tissue site (e.g. serving as the attachment device 404). In some embodiments, the base drape layer 620 may form the attachment device.

[0076] In use, method embodiments for providing negative-pressure therapy to a tissue site, for example using one of the dressing embodiments with support layer described herein, may comprise applying the dressing to the tissue site to seal the tissue site for negative-pressure therapy; and providing negative pressure to the dressing (and thereby to the tissue site) while the support layer remains in place on or within a drape of the dressing (e.g. without removing the support layer from the dressing). Some embodiments may further comprise providing a dressing having a drape with integral support layer. In some embodiments, the dressing may further comprise an integral dressing assemblage (e.g. with the dressing assemblage pre-atached to the drape and/or with the cover of the dressing assemblage forming the outer drape layer), and the method may further comprise adhering the dressing in place on the tissue site via the adhesive of the contact surface of the base drape layer. In other embodiments, the dressing assemblage may be initially separate from the drape, and the drape may comprise an outer drape layer with an interface aperture, and the method may further comprise adhering the drape in place on the tissue site (for example, via the adhesive of the contact surface of the base drape layer); and adhering the dressing assemblage over the interface aperture in the outer drape layer (e.g. on the second surface of the outer drape layer), for example using the atachment device of the dressing assemblage. In some embodiments, adhering the dressing assemblage over the interface aperture may comprise aligning the treatment aperture of the dressing assemblage with the interface aperture of the outer drape layer. In other embodiments, the drape may be initially separate from a manifold and may not have an aperture in the outer surface (e.g. the outer drape layer may form a cover configured to seal the tissue site for negative-pressure therapy), and the method may further comprise disposing the manifold on the tissue site; and disposing and adhering the drape over the manifold to seal the tissue site for negative-pressure therapy. In some embodiments, adhering the drape may comprise adhering the contact surface of the base drape layer to the tissue site.

[0077] Also disclosed are examples of methods of manufacturing a negative-pressure dressing or drape, similar to the embodiments described herein, which may comprise: providing an outer drape layer having adhesive on a first surface and no adhesive on a second surface; providing a support layer having an interior aperture; providing a base drape layer having a base aperture and having adhesive on both a contact surface and an exterior surface; disposing and adhering the support layer between the outer drape layer and the base drape layer, with the support layer adhered to the first surface of the outer drape layer and adhered to the exterior surface of the base drape layer; wherein the support layer provides support around the perimeter of the drape and the interior aperture aligns with the base aperture. In some embodiments, the outer drape may further comprise an interface aperture (which may be smaller than the interior aperture of the support layer and/or sized similar to a treatment aperture of a dressing assemblage), and the method may further comprise aligning the interface aperture with the interior aperture. Some embodiments may further comprise aligning the base aperture and the interior aperture. In some embodiment, providing an outer drape layer may comprise providing a film having high MVTR; and applying adhesive to the first surface (and not to the second surface). In some embodiments, providing an outer drape layer may further comprise forming an interface aperture in a polymer film. In some embodiments, providing an outer drape may comprise providing a cover (e.g. without an aperture and/or configured to seal the tissue site for negative-pressure therapy) configured to be disposed over a manifold and to have a flange extending beyond the manifold, wherein the flange may form the outer drape layer.

[0078] Some embodiments may further comprise providing a dressing assembly and ataching the dressing assembly to the second surface of the outer drape layer over the interface aperture of the outer drape layer. In some embodiments, the dressing assembly may comprise: an attachment device having a treatment aperture; a manifold configured to be at least partially exposed to the tissue site through the treatment aperture; and/or a cover configured to be disposed over the manifold and coupled to the attachment device around the manifold. In some embodiments, the interface aperture is approximately the same size as the treatment aperture. In some embodiments, the support layer may be configured to be semi-rigid. In some embodiments, providing the support layer may comprise providing a polymer film (e.g. which may be thicker and/or stiffer than the outer drape layer and/or the base drape layer); and forming (e.g. cutting) the interior aperture in the polymer film. In some embodiments, the interior aperture may be larger than the treatment aperture and/or the interface aperture. In some embodiments, the polymer film of the support layer may be formed of material with a low MVTR; and providing the support layer may further comprise forming a plurality of apertures in the polymer film configured to provide MVTR similar to the outer drape layer and/or cover. In some embodiments, providing the support layer may comprise embedding carbon fibers within a polymer film. In some embodiments, the carbon fibers may form a mesh. For example, embedding the carbon fibers within a polymer film may comprise providing a (woven) fabric sheet and/or mesh of carbon fibers; and encapsulating the fabric sheet or mesh within the polymer film of the support layer. In some embodiments, providing the base drape layer may comprise providing a film (e.g. similar to that of the outer drape layer and/or cover); and forming (e.g. cutting) the base aperture in the film, wherein the base aperture is approximately the same size as the interior aperture. In some embodiments, forming the base drape layer may further comprise applying adhesive to both the contact surface and the exterior surface of the base drape layer.

[0079] The systems, apparatuses, and methods described herein may provide significant advantages. For example, the supported drape may improve the ease and accuracy of application of the drape to the tissue site, and/or may reduce the number of scrapped dressings or drapes. For example, the supported drape and/or dressing may prevent the drape from folding over and adhering to itself, and this may improve the process for applying the dressing/drape while allowing the dressing/drape to be shaped to the tissue site (e.g. even to curved anatomy). This may also prevent waste, since drapes that fold and adhere to themselves must be discarded. Such a reduction in waste may also reduce cost of care. The supported dressing/drape embodiments may also allow for the effective use of larger dressings/drapes. In some embodiments, the supported drape may also improve reliability and/or manufacturability by eliminating the need for a kiss-cut process for forming a separate, removable material (since such a cutting process could inadvertently pierce the drape so that it is no longer effectively occlusive due to micro-tears or pin-holes).

[0080] If something is described as “exemplary” or an “example”, it should be understood that refers to a non-exclusive example. The terms “about” or “approximately” or the like, when used with a number, may mean that specific number, or alternatively, a range in proximity to the specific number as understood by persons of skill in the art field (for example, +/-10%). Use of broader terms such as “comprises”, “includes”, and “having” should be understood to provide support for narrower terms such as “consisting of’, “consisting essentially of’, and “comprised substantially of’. Use of the term “optionally”, “may”, “might”, “possibly”, “could”, “can”, “would”, “should”, “preferably”, “typically”, “often” and the like with respect to any element, component, feature, characteristic, etc. of an embodiment means that the element, component, feature, characteristic, etc. is not required, or alternatively, the element, component, feature, characteristic, etc. is required, both alternatives being within the scope of the embodiment(s). Such element, component, feature, characteristic, etc. may be optionally included in some embodiments, or it may be excluded (e.g. forming alternative embodiments, all of which are included within the scope of disclosure). Section headings used herein are provided for consistency and convenience, and shall not limit or characterize any invention(s) set out in any claims that may issue from this disclosure. If a reference numeral is used to reference a specific example of a more general term, then that reference numeral may also be used to refer to the general term (or vice versa).

[0081] While shown in a few illustrative embodiments, a person having ordinary skill in the art will recognize that the systems, apparatuses, and methods described herein are susceptible to various changes and modifications that fall within the scope of the appended claims. Moreover, descriptions of various alternatives using terms such as “or” do not require mutual exclusivity unless clearly required by the context, and the indefinite articles "a" or "an" do not limit the subject to a single instance unless clearly required by the context. Components may be also be combined or eliminated in various configurations for purposes of sale, manufacture, assembly, or use. For example, in some configurations the dressing, the container, or both may be eliminated or separated from other components for manufacture or sale. In other example configurations, the controller may also be manufactured, configured, assembled, or sold independently of other components.

[0082] The appended claims set forth novel and inventive aspects of the subject matter described above, but the claims may also encompass additional subject matter not specifically recited in detail. For example, certain features, elements, or aspects may be omitted from the claims if not necessary to distinguish the novel and inventive features from what is already known to a person having ordinary skill in the art. Features, elements, and aspects described in the context of some embodiments may also be omitted, combined, or replaced by alternative features serving the same, equivalent, or similar purpose without departing from the scope of the invention defined by the appended claims. Also, features, elements, and aspects described with respect to a particular embodiment may be combined with features, elements, and aspects described with respect to one or more other embodiments.

Claims

What is claimed is:

1. A dressing for negative-pressure therapy at a tissue site, comprising: an attachment device having a treatment aperture; a manifold configured to be at least partially exposed to the tissue site through the treatment aperture; a cover configured to be disposed over the manifold and coupled to the attachment device around the manifold; and a drape having an integral, semi-rigid support layer.

2. The dressing of claim 1, wherein the support layer is configured to support the drape around a perimeter of the drape.

3. The dressing of claim 1 wherein the support layer comprises an interior aperture, which is larger than the treatment aperture.

4. The dressing of claim 3, wherein the drape further comprises an outer drape layer and a base drape layer, with the support layer located therebetween.

5. The dressing of claim 4, wherein: the outer drape layer comprises an interface aperture; the base drape layer comprises a base aperture; the interface aperture is smaller than the interior aperture of the support layer; and the interface aperture and the base aperture are aligned with each other and with the interior aperture of the support layer.

6. The dressing of claim 4, wherein the support layer is stacked between and coupled to both the outer drape layer and the base drape layer, and the base drape layer comprises an adhesive on a surface opposite the support layer.

7. The dressing of claim 1, wherein the support layer comprises a polyurethane film which is approximately 0.01 inch thick.

8. The dressing of claim 1, wherein the support layer comprises a polymer film embedded with carbon fibers.

9. A drape for negative-pressure therapy on a tissue site, comprising: an outer drape layer; a base drape layer; and a semi-rigid support layer located between and coupled to the outer drape layer and the base drape layer.

10. The drape of claim 9, wherein the semi-rigid support layer is sufficiently stiff to render the drape self-supporting.

11. The drape of claim 9, wherein: the outer drape layer has a high MVTR;

25 the outer drape layer is configured to seal the tissue site for negative-pressure therapy; and the support layer has MVTR similar to the outer drape layer.

12. The drape of claim 9, wherein the support layer is configured to support the drape around a perimeter of the drape.

13. The drape of claim 9, wherein the support layer comprises an interior aperture.

14. The drape of claim 13, wherein: the outer drape layer comprises a first surface, configured to face towards the support layer, and a second surface opposite the first surface; the first surface is adhesive and the second surface is not; the base drape layer comprises a contact surface configured to contact the tissue site and an exterior surface opposite the contact surface; and both the contact surface and the exterior surface are adhesive.

15. The drape of claim 14, wherein the outer drape layer comprises an interface aperture, the base drape layer comprises a base aperture, and the interface aperture and the base aperture are aligned with each other and with the interior aperture of the support layer.

16. The drape of claim 13, wherein the outer drape layer is configured to be disposed over a manifold and to sealingly enclose the manifold to the tissue site for negative-pressure therapy.

17. The drape of claim 16, wherein the base drape layer comprises a base aperture, and the base aperture is aligned with the interior aperture of the support layer.

18. A method for manufacturing a drape/dressing, comprising: providing an outer drape layer having adhesive on a first surface and no adhesive on a second surface; providing a support layer having an interior aperture; providing a base drape layer having a base aperture and having adhesive on both a contact surface and an exterior surface; disposing and adhering the support layer between the outer drape layer and the base drape layer, with the support layer coupled to the first surface of the outer drape layer and coupled to the exterior surface of the based drape layer; wherein the support layer provides support around the perimeter of the drape and the interior aperture aligns with the base aperture.

19. The method of claim 18, wherein the outer drape further comprises an interface aperture, the method further comprising aligning the interface aperture with the interior aperture. 0. The method of claim 18, wherein providing the support layer comprises: providing a polymer film; and forming the interior aperture in the polymer film. 1. A dressing, for negative-pressure therapy at a tissue site, comprising a drape having an integral, semi-rigid support layer.

22. The dressing of claim 21, wherein the drape is configured to seal the tissue site for negativepressure therapy.

23. The dressing of claim 21, wherein the support layer is embedded within the drape.

24. The dressing of claim 21, wherein the support layer is configured to support the drape substantially only around a perimeter of the drape.

25. The dressing of claim 21, wherein the support layer comprises an interior aperture.

26. The dressing of claim 25, further comprising: an attachment device having a treatment aperture; a manifold configured to be at least partially exposed to the tissue site through the treatment aperture; and a cover configured to be disposed over the manifold and coupled to the attachment device around the manifold.

27. The dressing of claim 26, wherein the attachment device, manifold, and cover may be preassembled to form a unitary dressing assemblage.

28. The dressing of claim 26, wherein the interior aperture of the support layer is larger than the treatment aperture.

29. The dressing of any of claims 26-28, wherein the drape further comprises an outer drape layer and a base drape layer, with the support layer located therebetween.

30. The dressing of claim 29, wherein the outer drape layer comprises an interface aperture, the base drape layer comprises a base aperture, and the interface aperture and the base aperture are each aligned with the interior aperture of the support layer.

31. The dressing of claim 30, wherein the interface aperture is approximately the size of the treatment aperture.

32. The dressing of claim 30, wherein the interface aperture is smaller than the interior aperture of the support layer.

33. The dressing of claim 30, wherein the base aperture is approximately the same size as the interior aperture of the support layer.

34. The dressing of claim 29, wherein the outer drape layer is configured to provide a seal for negative-pressure therapy.

35. The dressing of claim 21, wherein the support layer provides sufficient support to the drape so that the drape is self-supporting prior to application to the tissues site, while allowing effective application of the drape to the tissue site.

36. The dressing of claim 21, wherein the semi-rigid support layer is sufficiently stiff to render the drape self-supporting.

37. The dressing of claim 29, wherein the outer drape comprises a first surface, configured to face towards the support layer, and a second surface opposite the first surface, wherein the first surface is adhesive and the second surface is not adhesive.

38. The dressing of claim 37, wherein the base drape layer comprises a contact surface, configured to contact the tissue site, and an exterior surface opposite the contact surface, wherein both the contact surface and the exterior surface are adhesive.

39. The dressing of claim 29, wherein the support layer is stacked between and coupled to both the outer drape layer and the base drape layer, and the base drape layer comprises adhesive on a surface opposite the support layer.

40. The dressing of claim 29, wherein the outer drape layer, the support layer, and the base drape layer are pre-formed as an integral, unitary drape.

41. The dressing of claim 29, wherein substantially the entire base drape layer is adhered to substantially the entire support layer, and only a perimeter of the outer drape layer is adhered to the support layer.

42. The dressing of claim 21, wherein the support layer comprise a polyurethane film which is approximately 0.01 inch thick.

43. The dressing of claim 29, wherein the outer drape layer has a high MVTR, and the support layer is configured to have an MVTR similar to outer drape layer.

44. The dressing of claim 21, wherein the support layer comprises a polymer film and a plurality of perforations in the polymer film.

45. The dressing of claim 21, wherein the support layer comprises a polymer film embedded with carbon fibers.

46. The dressing of 45, wherein the carbon fibers are formed into a fabric sheet within the polymer film.

47. The dressing of claim 21, wherein the support layer comprises a polycarbonate film embedded with carbon fibers.

48. The dressing of claim 29, wherein a portion of the cover forms the outer drape layer.

49. The dressing of claim 29, wherein the cover comprises a flange extending outward beyond a perimeter of the manifold, and the flange of the cover forms the outer drape layer.

50. The drape of claim 15, wherein the interface aperture is smaller than the interior aperture of the support layer.

51. The drape of any of claims 15 or 50, wherein the base aperture is approximately the same size as the interior aperture of the support layer.

52. The method of claim 18, further comprising aligning the base aperture and the interior aperture.

53. The method of claim 52, further comprising aligning the interior aperture and the interface aperture.

54. The method of claim 18, wherein providing an outer drape layer comprises providing a film having high MVTR; and applying adhesive to the first surface but not to the second surface.

55. The method of claim 18, wherein providing an outer drape layer further comprises forming an interface aperture in a film.

28

56. The method of claim 18, wherein providing an outer drape comprises providing a cover configured to be disposed over a manifold and to have a flange extending beyond the manifold, wherein the flange forms the outer drape layer.

57. The method of claim 19, further comprising providing a dressing assembly and attaching the dressing assembly to the second surface of the outer drape over the interface aperture of the outer drape.

58. The method of claim 57, wherein the dressing assembly comprises: an attachment device having a treatment aperture; a manifold configured to be at least partially exposed to the tissue site through the treatment aperture; and a cover configured to be disposed over the manifold and coupled to the attachment device around the manifold.

59. The method of claim 18, wherein the support layer is configured to be semi-rigid.

60. The method of claim 20, wherein the polymer film of the support layer is formed of material with a low MVTR; and providing the support layer further comprise forming a plurality of perforations in the polymer film configured to provide MVTR similar to the outer drape layer.

61. The method of claim 18, wherein providing the support layer comprises embedding carbon fibers within a polymer film.

62. The method of claim 61, wherein embedding the carbon fibers within a polymer film comprises providing a fabric sheet of carbon fibers; and encapsulating the fabric sheet within the polymer film.

63. The method of 18, wherein providing the base drape layer comprises providing a film; forming the base aperture in the film; and applying adhesive to both the contact surface and the exterior surface.

64. The systems, dressings, apparatuses, and methods substantially as shown and described herein.

29