Negative pressure wound therapy dressing material including in vivo light sensing

Abstract

A dressing material for treating a tissue site by negative pressure includes a cover, a wound contact layer, a manifold, and at least one sensor. The cover includes a first surface and a second surface. The wound contact layer includes a first surface and a second surface, and the second surface of the wound contact layer is configured to contact the tissue site. The manifold includes a first surface and a second surface. The manifold is configured to be disposed between the second surface of the cover and the first surface of the wound contact layer. The at least one sensor can include a plurality of oxygen sensing molecules dissolved in a polymer matrix. The at least one sensor is configured to change color to indicate the sensed oxygen level when the at least one sensor is acted upon by a light source.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 351,029, filed on June 10, 2022, which is hereby incorporated by reference in its entirety.

[0002] The invention described in the appended claims generally relates to tissue treatment systems, and more specifically, but not limited to, negative pressure wound therapy dressings including in - vivo optical sensors.

Background Art

[0003] Clinical research and clinical practice have shown that reducing the pressure near a tissue site can enhance and accelerate the growth of new tissue at the tissue site. There are numerous applications of this phenomenon, but it has proven to be particularly advantageous for treating wounds. Regardless of the cause of the wound, whether due to trauma, surgery, or another cause, appropriate care of the wound is important for the outcome. Treatment of wounds or other tissues by reducing pressure can generally be referred to as "negative pressure therapy", but is also known by other names, including, for example, "negative pressure wound therapy", "decompression therapy", "vacuum therapy", "vacuum - assisted closure", and "local negative pressure". Negative pressure therapy can provide many benefits, including the migration of epithelial and subcutaneous tissues, improvement of blood flow, and micro - deformation of tissues at the wound site. Overall, these benefits can enhance the development of granulation tissue and shorten the healing time.

[0004] Also, it is widely accepted that cleaning tissue sites can be very beneficial for the growth of new tissue. For example, wounds or cavities can be flushed with a liquid solution for therapeutic purposes. These clinical procedures are generally referred to as "irrigation" and "lavage", respectively. "Instillation" is another clinical procedure that generally refers to the process of slowly introducing fluid into a tissue site and leaving the fluid in place for a predetermined period of time before removing the fluid. For example, instillation of a topical treatment solution onto a wound bed, in combination with negative pressure therapy, can further promote wound healing by liberating soluble contaminants within the wound bed and removing infectious agents. As a result, the soluble bacterial load can be reduced, contaminants can be removed, and the wound can be cleaned.

[0005] The clinical benefits of negative pressure therapy and / or instillation therapy are well known, but improvements in therapy systems, components, and processes can provide benefits to healthcare providers and patients. SUMMARY OF THE INVENTION

[0006] The appended claims describe novel and useful systems, devices, and methods for sensing changes at or near a wound site in a negative pressure therapy environment. Exemplary embodiments are also provided to enable one of ordinary skill in the art to make and use the claimed subject matter.

[0007] For example, in some embodiments, a dressing material for treating a tissue site by negative pressure is described. The dressing material can include a cover, a wound contact layer including at least one sensor, a first film layer, and a manifold. The cover can include a first surface and a second surface. The wound contact layer can include a first surface, a second surface, and a central opening. The second surface of the wound contact layer can be configured to contact a region around the wound of the tissue site. The first film layer can include a first surface and a second surface. The second surface of the first film layer can be configured to contact the wound of the tissue site. The manifold can include a first surface and a second surface. The manifold can be configured to be disposed between the second surface of the cover and the first surface of the first film layer. The at least one sensor can include a plurality of oxygen sensing molecules dissolved in a polymer matrix. The at least one sensor can be configured to change color to indicate the sensed oxygen level when the at least one sensor is acted upon by a light source.

[0008] In some exemplary embodiments, the wound contact layer can further include a peripheral portion surrounding a central portion. The peripheral portion can include a plurality of openings. In some exemplary embodiments, the at least one sensor can be disposed within one of the plurality of openings of the wound contact layer. In other exemplary embodiments, the at least one sensor can be disposed between the first surface of the wound contact layer and the second surface of the cover. The at least one sensor can be offset from the plurality of openings of the wound contact layer.

[0009] In some exemplary embodiments, at least one sensor can include an oxygen sensing film. In some exemplary embodiments, the oxygen sensing film can include a low oxygen permeability polymer or a high oxygen permeability polymer. In some exemplary embodiments, the low oxygen permeability polymer can include one of polyvinyl alcohol, ethylene vinyl alcohol, polyacrylonitrile, and polyvinylidene chloride. In some exemplary embodiments, the high oxygen permeability polymer can include one of silicone and polyolefin elastomer.

[0010] In some exemplary embodiments, at least one sensor can include a multi-sensor configured to detect fluid level, oxygen level, and pH level.

[0011] Another dressing material for treating a tissue site by negative pressure is also described herein. The dressing material can include a cover including at least one sensor, a wound contact layer, a first film layer, and a manifold. The cover can include a first surface and a second surface. The wound contact layer can include a first surface, a second surface, and a central opening. The second surface of the wound contact layer can be configured to contact the area around the wound of the tissue site. The first film layer can include a first surface and a second surface. The second surface of the first film layer can be configured to contact the wound of the tissue site. The manifold can include a first surface and a second surface. The manifold can be configured to be disposed between the second surface of the cover and the first surface of the first film layer. At least one sensor can include a plurality of oxygen sensing molecules dissolved in a polymer matrix. At least one sensor can be configured to change color to indicate the sensed oxygen level when the at least one sensor is acted upon by a light source.

[0012] In other exemplary embodiments, at least one sensor can be disposed within a recess in the first surface of the cover such that the at least one sensor is aligned with one of the plurality of openings of the wound contact layer. In some exemplary embodiments, the dressing material may further include a recess lid removably coupled to the first surface of the cover. The recess lid can be configured to seal at least one sensor within the recess in the first surface of the cover. In other exemplary embodiments, at least one sensor can be disposed on the first surface of the cover such that the sensor is aligned with one of the plurality of openings of the wound contact layer.

[0013] In some exemplary embodiments, the cover can further include a central portion having a central opening and a peripheral portion. The peripheral portion of the cover can be configured to couple to the peripheral portion of the wound contact layer. In some exemplary embodiments, the cover can further include a second film layer having a first surface and a second surface. The second film layer can be configured to substantially align with the central opening of the cover, and the second surface of the second film layer can be coupled to the first surface of the manifold. In some exemplary embodiments, at least one sensor can be disposed within a recess in the first surface of the second film layer. In some exemplary embodiments, the dressing material may further include a recess lid removably coupled to the first surface of the second film layer. The recess lid can be configured to seal at least one sensor within the recess in the first surface of the second film layer. In some embodiments, at least one sensor can be disposed between the first surface of the manifold and the second surface of the second film layer. In other embodiments, the dressing material can further include at least one sealed cavity between the first surface of the manifold and the second surface of the second film layer. At least one sensor can be disposed within the at least one sealed cavity.

[0014] Another dressing material for treating a tissue site by negative pressure is also described herein. The dressing material can include a cover, a wound contact layer, a first film layer, a manifold, and at least one sensor. The cover can include a first surface and a second surface. The wound contact layer can include a first surface, a second surface, and a central opening. The second surface of the wound contact layer can be configured to contact the area around the wound of the tissue site. The first film layer can include a first surface and a second surface. The second surface of the first film layer can be configured to contact the wound of the tissue site. The manifold can include a first surface and a second surface. The manifold can be configured to be disposed between the second surface of the cover and the first surface of the first film layer. At least one sensor can be embedded in the second surface of the first film layer. At least one sensor can include a plurality of oxygen sensing molecules dissolved in a polymer matrix. At least one sensor can be configured to change color to indicate the sensed oxygen level when the at least one sensor is acted upon by a light source.

[0015] Another dressing material for treating a tissue site by negative pressure is also described herein. The dressing material can include a cover, a wound contact layer, a first film layer, a manifold, and at least one sensor. The cover can include a first surface and a second surface. The wound contact layer can include a first surface, a second surface, and a central opening. The second surface of the wound contact layer can be configured to contact the area around the wound of the tissue site. The first film layer can include a first surface and a second surface. The second surface of the first film layer can be configured to contact the wound of the tissue site. The manifold can include a first surface and a second surface. The manifold can be configured to be disposed between the second surface of the cover and the first surface of the first film layer. The at least one sensor can be disposed between the second surface of the manifold and the first surface of the first film layer. The at least one sensor can include a plurality of oxygen sensing molecules dissolved in a polymer matrix. The at least one sensor can be configured to change color to indicate the sensed oxygen level when the at least one sensor is acted upon by a light source.

[0016] In some exemplary embodiments, the at least one sensor can be disposed proximate to a window of the manifold such that the at least one sensor is visible through the window of the manifold.

[0017] Methods of treating tissue sites by negative pressure are also described herein. The method can include placing a dressing material over the tissue site, applying negative pressure from a negative pressure source to the dressing material, and monitoring the dressing material for changes in sensed parameters at the tissue site. The dressing material can include a cover, a wound contact layer, a manifold, and at least one sensor. The cover can include a first surface and a second surface. The wound contact layer can include a first surface and a second surface. The second surface of the wound contact layer can be configured to contact the tissue site. The manifold can include a first surface and a second surface. The manifold can be configured to be disposed between the second surface of the cover and the first surface of the wound contact layer. The at least one sensor can include a plurality of parameter sensing molecules dissolved in a polymer matrix. The at least one sensor can be configured to indicate a sensed parameter when the at least one sensor is acted upon by a light source.

[0018] In some exemplary embodiments, monitoring the dressing material for changes in sensed parameters at the tissue site can include detecting a change in color in the at least one sensor when the at least one sensor is acted upon by a light source.

[0019] In some exemplary embodiments, the sensed parameter can include at least one of fluid level, oxygen level, and pH.

[0020] A wound contact layer for treating a tissue site is also described herein. The wound contact layer can include a central portion, a peripheral portion, and at least one sensor. In some exemplary embodiments, the peripheral portion can surround the central portion. In some exemplary embodiments, the peripheral portion can include a plurality of openings. In some exemplary embodiments, the at least one sensor can include a plurality of oxygen sensing molecules dissolved in a polymer matrix. The at least one sensor can be integrated into the peripheral portion away from each of the plurality of openings. In some exemplary embodiments, the at least one sensor can be configured to change color to indicate the sensed oxygen level when the at least one sensor is acted upon by a light source.

[0021] The objects, advantages, and preferred aspects of the claimed subject matter can be best understood by reference to the following detailed description of exemplary embodiments in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0022]

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[0023] The following description of the exemplary embodiments provides information that enables those skilled in the art to make and use the subject matter recited in the appended claims, but certain details that are well known in the art may be omitted. Accordingly, the following detailed description should be construed as illustrative and not in a limiting sense.

[0024] FIG. 1 is a block diagram of an exemplary embodiment of a therapy system 100 that can provide negative pressure therapy using instillation of a topical treatment solution to a tissue site in accordance with the present specification.

[0025] The term "tissue site" in this context broadly refers to a wound, defect, or other treatment target located on or within a tissue, including but not limited to bone tissue, adipose tissue, muscle tissue, nerve tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendon, or ligament. Examples of wounds can include, for example, chronic, acute, traumatic, subacute, and lacerated wounds, partial thickness burns, ulcers (such as diabetic ulcers, pressure ulcers, or venous insufficiency ulcers), skin flaps, and grafts. The term "tissue site" can also refer to any area of tissue that is not necessarily a wound or defect, but rather an area where additional tissue growth may be desired or promoted. For example, negative pressure can be applied to a tissue site to grow additional tissue that can be harvested and transplanted.

[0026] Therapy system 100 can include a negative pressure source or supply, such as negative pressure source 105, and one or more distribution components. The distribution components are preferably separable and can be disposable, reusable, or recyclable. Examples of distribution components that can be associated with some examples of therapy system 100 are dressing materials, such as dressing material 110, and fluid containers, such as container 115. As illustrated in the example of FIG. 1, dressing material 110 can comprise, consist essentially of, or consist of tissue interface 120, cover 125, or both in some embodiments.

[0027] A fluid conduit is another exemplary example of a distribution component. In this context, a "fluid conduit" broadly includes tubes, pipes, hoses, ducts, or other structures having one or more lumens or open passages adapted to convey fluid between two ends. Typically, a tube is an elongated cylindrical structure having some flexibility, but the geometry and rigidity can vary. Further, some fluid conduits can be molded within other components or otherwise integrally combined with other components. A distribution component can also include or be provided with an interface or fluid port to facilitate connecting and disconnecting other components. In some embodiments, for example, a dressing interface can facilitate connecting a fluid conduit to a dressing 110. For example, such a dressing interface can be a SENSAT.R.A.C. (trademark) Pad available from Kinetic Concepts, Inc. (San Antonio, Texas).

[0028] Therapy system 100 can also include a controller, such as a regulator or controller 130. Additionally, therapy system 100 can include sensors for measuring operating parameters and providing a feedback signal indicative of the operating parameters to controller 130. As illustrated in FIG. 1, for example, therapy system 100 can include a first sensor 135 and a second sensor 140 coupled to controller 130.

[0029] The therapy system 100 may also include an infusion solution source. For example, the solution source 145 can be fluidly coupled to the dressing 110, as shown in the exemplary embodiment of FIG. 1. The solution source 145 can be fluidly coupled to a positive pressure source, such as the positive pressure source 150, a negative pressure source, such as the negative pressure source 105, or both in some embodiments. A regulator, such as the infusion regulator 155, can also be fluidly coupled to the solution source 145 and the dressing 110 to ensure an appropriate dosage of the infusion solution (e.g., saline) to the tissue site. For example, the infusion regulator 155 can include a piston that can be pneumatically actuated by the negative pressure source 105 to draw the infusion solution from the solution source during the negative pressure interval and to infuse the solution into the dressing during the venting interval. Additionally, or alternatively, the controller 130 can be coupled to the negative pressure source 105, the positive pressure source 150, or both to control the dosage of the infusion solution to the tissue site. In some embodiments, the infusion regulator 155 can also be fluidly coupled to the negative pressure source 105 through the dressing 110, as shown in the embodiment of FIG. 1.

[0030] Some components of the therapy system 100 can be housed within or used in conjunction with other components, such as sensors, processing units, alarm indicators, memories, databases, software, display devices, or user interfaces, that further facilitate the therapy. For example, in some embodiments, the negative pressure source 105 can be combined with the controller 130, the solution source 145, and other components in a therapy unit 160.

[0031] Generally, the components of the therapy system 100 can be coupled directly or indirectly. For example, the negative pressure source 105 can be directly coupled to the container 115 and indirectly coupled to the dressing material 110 through the container 115. In some contexts, couplings can include fluid couplings, mechanical couplings, thermal couplings, electrical couplings, or chemical couplings (such as chemical bonds), or some combinations thereof. For example, the negative pressure source 105 can be electrically coupled to the controller 130 and fluidly coupled to one or more distribution components to provide a fluid path to the tissue site. In some embodiments, the components can also be coupled by physical proximity, by integrating them into a single structure, or by forming them from the same piece of material.

[0032] A negative pressure supply, such as the negative pressure source 105, can be, for example, a reservoir of negative pressure air, or a manual or electrically driven device such as a vacuum pump, a suction pump, a wall suction port available in many medical facilities, or a micropump. "Negative pressure" generally refers to a pressure less than a local ambient pressure, such as the ambient pressure in the local external environment relative to a sealed treatment environment. In many cases, the local ambient pressure can also be the atmospheric pressure at the location where the tissue site is located. Alternatively, the pressure can be less than the hydrostatic pressure associated with the tissue at the tissue site. Unless otherwise indicated, the pressure values described herein are gauge pressures. References to an increase in negative pressure typically refer to a decrease in absolute pressure, while a decrease in negative pressure typically refers to an increase in absolute pressure. The amount and nature of the negative pressure provided by the negative pressure source 105 can vary according to treatment requirements, but the pressure is generally a low vacuum, generally referred to as a rough vacuum, of -5 mmHg (-667 Pa) to -500 mmHg (-66.7 kPa). A typical treatment range is -50 mmHg (-6.7 kPa) to -300 mmHg (-39.9 kPa).

[0033] Container 115 represents a container, canister, pouch, or other storage component that can be used to manage exudate and other fluids removed from a tissue site. In many environments, a rigid container may be preferred or necessary for collecting, storing, and disposing of fluids. In other environments, the fluids may be appropriately discarded without being stored in a rigid container, although reusable containers can reduce the waste and costs associated with negative pressure therapy.

[0034] A controller, such as controller 130, can be a microprocessor or computer programmed to operate one or more components of therapy system 100, such as negative pressure source 105. In some embodiments, for example, controller 130 can be a microcontroller, which generally comprises a processor core and memory programmed to directly or indirectly control one or more operating parameters of therapy system 100. Operating parameters can include, for example, the power applied to negative pressure source 105, the pressure generated by negative pressure source 105, or the pressure distributed to tissue interface 120. Controller 130 is also preferably configured to receive one or more input signals, such as feedback signals, and is programmed to modify one or more operating parameters based on the input signals.

[0035] Sensors such as the first sensor 135 and the second sensor 140 can be devices operable to detect or measure a physical phenomenon or property, and generally can provide a signal indicative of the detected or measured phenomenon or property. For example, the first sensor 135 and the second sensor 140 can be configured to measure one or more operating parameters of the therapy system 100. In some embodiments, the first sensor 135 can be a transducer configured to measure the pressure in the pneumatic path and convert the measurement into a signal indicative of the measured pressure. In some embodiments, for example, the first sensor 135 can be a piezoresistive strain gauge. In some embodiments, the second sensor 140 can optionally measure an operating parameter of the negative pressure source 105 such as voltage or current. Preferably, the signals from the first sensor 135 and the second sensor 140 are suitable as input signals to the controller 130, although in some embodiments some signal conditioning may be appropriate. For example, the signal may need to be filtered or amplified before being processed by the controller 130. Typically, the signal is an electrical signal, although it can be represented in other forms such as an optical signal.

[0036] The tissue interface 120 can generally be adapted to contact the tissue site either partially or fully. The tissue interface 120 can take many forms and can have many sizes, shapes, or thicknesses depending on various factors such as the type of treatment being performed or the nature and size of the tissue site. For example, the size and shape of the tissue interface 120 can be adapted to the contour of a deeply irregularly shaped tissue site. Any or all of the surfaces of the tissue interface 120 can have a wavy, rough, or jagged profile.

[0037] In some embodiments, the tissue interface 120 can comprise or consist essentially of a manifold. A manifold in this context can comprise or consist essentially of means for collecting or distributing fluid across the tissue interface 120 under pressure. For example, the manifold can be adapted to receive a negative pressure from a source and distribute the negative pressure through a plurality of openings across the tissue interface 120, which can have the effect of collecting fluid across the tissue site and drawing the fluid toward the source. In some embodiments, the fluid path can be reversed or a secondary fluid path can be provided to facilitate delivering fluid, such as fluid from a drip solution source, to the tissue site.

[0038] In some exemplary embodiments, the manifold can comprise a plurality of pathways that can be interconnected to improve the distribution or collection of fluid. In some exemplary embodiments, the manifold can comprise or consist essentially of a porous material having interconnected fluid pathways. Examples of suitable porous materials that can be adapted to form interconnected fluid pathways (e.g., channels) include cellular foams such as open-cell foams like reticulated foams, aggregates of porous tissue, and other porous materials such as generally gauze or felt-like mats that include pores, edges, and / or walls. Liquids, gels, and other foams can also contain or be cured to contain gaps and fluid pathways. In some embodiments, the manifold can additionally or alternatively comprise protrusions that form interconnected fluid pathways. For example, the manifold can be molded to provide surface protrusions that define interconnected fluid pathways.

[0039] In some embodiments, the tissue interface 120 can comprise, or can consist essentially of, an open-cell foam having a pore size and free volume that can vary according to the requirements of a given therapy. For example, an open-cell foam having at least 90% free volume can be suitable for many therapeutic applications, and for some types of therapy, a foam having an average pore size in the range of 400 - 600 microns (40 - 50 pores per inch) can be particularly suitable. The tensile strength of the tissue interface 120 can also vary according to the requirements of a given therapy. For example, the tensile strength of the foam can be increased for the instillation of a topical treatment solution. The 25% compression load deflection of the tissue interface 120 can be at least 0.35 pounds per square inch, and the 65% compression load deflection can be at least 0.43 pounds per square inch. In some embodiments, the tensile strength of the tissue interface 120 can be at least 10 pounds per square inch. The tissue interface 120 can have a tear strength of at least 2.5 pounds per inch. In some embodiments, the tissue interface can be a foam composed of a polyol such as polyester or polyether, an isocyanate such as toluene diisocyanate, and a polymerization regulator such as amine and tin compounds. In some examples, the tissue interface 120 can be an open-cell polyurethane foam such as that found in both the GRANUFOAM™ dressing or the V.A.C. VERAFLO™ dressing, both available from Kinetic Concepts, Inc. (San Antonio, Texas).

[0040] The thickness of the tissue interface 120 can also vary according to the requirements of the indicated therapy. For example, the thickness of the tissue interface can be made thinner so as to reduce the tension on the surrounding tissue. The thickness of the tissue interface 120 can also affect the conformity of the tissue interface 120. In some embodiments, a thickness in the range of about 5 millimeters to 10 millimeters can be appropriate.

[0041] The tissue interface 120 can be either hydrophobic or hydrophilic. In one example where the tissue interface 120 may be hydrophilic, the tissue interface 120 can also allow fluid to escape away from the tissue site while continuing to distribute negative pressure to the tissue site. The wicking properties of the tissue interface 120 can draw fluid away from the tissue site by capillary flow or other wicking mechanisms. An example of a hydrophilic material that may be suitable is an open-cell foam of polyvinyl alcohol such as the V.A.C. WHITEFOAM (trademark) dressing material available from Kinetic Concepts, Inc. (San Antonio, Texas). Other hydrophilic foams may include those made from polyethers. Other foams that may exhibit hydrophilic properties may include hydrophobic foams that are treated or coated to provide hydrophilicity.

[0042] In some embodiments, the tissue interface 120 can be constructed from a bioabsorbable material. Suitable bioabsorbable materials may include, but are not limited to, a polymer blend of polylactic acid (PLA) and polyglycolic acid (PGA). Polymer blends may also include, but are not limited to, polycarbonate, polyfumarate, and caprolactone. The tissue interface 120 can serve a further role as a scaffold for new cell growth, or a scaffold material can be used in conjunction with the tissue interface 120 to promote cell growth. A scaffold is generally a substance or structure used to enhance or promote cell growth or tissue formation, such as a three-dimensional porous structure that provides a template for cell growth. Exemplary examples of scaffold materials may include calcium phosphate, collagen, PLA / PGA, coral hydroxyapatite, carbonate, or processed allograft material.

[0043] In some embodiments, the cover 125 can provide protection from bacterial barriers and physical trauma. The cover 125 can also be constructed from a material that can reduce evaporative losses and provide a fluid seal between two components or between two environments such as between a treatment environment and a local external environment. The cover 125 can include, or consist of, for example, an elastic film or membrane that can provide a seal sufficient to maintain negative pressure at the tissue site with respect to a given source of negative pressure.

[0044] In some exemplary embodiments, the cover 125 can be a polymeric drape, such as a polyurethane film that is permeable to water vapor but impermeable to liquids. In other embodiments, the cover 125 may be impermeable to both water vapor and liquids. Such drapes typically have a thickness in the range of 25 to 50 microns. With respect to the permeable material, the permeability should generally be low enough so that the desired negative pressure can be maintained. The cover 125 can include one or more of, for example, polyurethanes (PU) such as hydrophilic polyurethane, cellulose derivatives, hydrophilic polyamides, polyvinyl alcohol, polyvinyl pyrrolidone, hydrophilic acrylics, silicones such as hydrophilic silicone elastomers, natural rubber, 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), copolyesters, and polyether block polyamide copolymers. Such materials are commercially available, for example, as Tegaderm® drapes from 3M Company (Minneapolis Minnesota), polyurethane (PU) drapes from Avery Dennison Corporation (Pasadena, California), polyether block polyamide copolymers (PEBAX) such as those made by Arkema S.A. (Colombes, France), and INSPIRE® 2301 and INSPIRE® 2327 polyurethane films commercially available from Exopack Advanced Coatings (Wrexham, United Kingdom). In some embodiments, the cover 125 can include INSPIRE® 2301 having an MVTR (upright cup technique) of 2600 g / m 2 / 24 hours and a thickness of about 30 microns.

[0045] A mounting device can be used to attach the cover 125 to a mounting surface such as an intact epidermis, gasket, or another cover. The mounting device can take many forms. For example, the mounting device can be a medically acceptable pressure-sensitive adhesive configured to bond the cover 125 to the epidermis around the tissue site. In some embodiments, for example, a part or all of the cover 125 can be coated with an adhesive, such as an acrylic adhesive, that can have a coating weight of about 25 to 65 grams per square meter (g.s.m.). In some embodiments, a thicker adhesive, or a combination of adhesives, can be applied to improve the seal and reduce leakage. Other exemplary embodiments of the mounting device can include double-sided tape, paste, hydrocolloid, hydrogel, silicone gel, or organogel.

[0046] The solution source 145 can also represent a container, canister, pouch, bag, or other storage component that can provide a solution for intravenous drip therapy. The composition of the solution can vary according to a given therapy, but examples of solutions that can be suitable for some prescriptions include hypochlorite-based solutions, silver nitrate (0.5%), sulfur-based solutions, biguanides, cationic solutions, and isotonic solutions.

[0047] During operation, the tissue interface 120 can be disposed within, covering, over, or otherwise proximate to the tissue site. For example, if the tissue site is a wound, the tissue interface 120 can partially or completely occlude the wound or be disposed over the wound. The cover 125 can be disposed over the tissue interface 120 and sealed to a mounting surface near the tissue site. For example, the cover 125 can be sealed to the tissue site around the periphery of the intact epidermis. Thus, the dressing 110 can provide a sealed treatment environment proximate to the tissue site substantially isolated from the external environment, and the negative pressure source 105 can reduce the pressure within the sealed treatment environment.

[0048] The process of reducing pressure can be illustratively described herein, for example, as "delivering", "distributing", or "generating" a negative pressure. Generally, exudate and other fluids flow along a fluid path towards a lower pressure. Thus, the term "downstream" typically means a position within a fluid path that is relatively closer to a negative pressure source or farther away from a positive pressure source. Conversely, the term "upstream" means a position that is relatively farther away from a negative pressure source or closer to a positive pressure source.

[0049] The negative pressure applied across the tissue site through the tissue interface 120 within the sealed treatment environment can cause macro and micro strain at the tissue site. The negative pressure can also remove exudate and other fluids from the tissue site, and the exudate and other fluids can be collected within the container 115.

[0050] In some embodiments, the controller 130 can receive and process data from one or more sensors, such as the first sensor 135. The controller 130 can also control the operation of one or more components of the therapy system 100 to manage the pressure delivered to the tissue interface 120. In some embodiments, the controller 130 can include an input for receiving a desired target pressure and can be programmed to process data regarding the setting and input of the target pressure applied to the tissue interface 120. In some exemplary embodiments, the target pressure can be a fixed pressure value that is set by an operator as the desired target negative pressure for therapy at the tissue site and is then provided as an input to the controller 130. The target pressure can vary depending on the type of tissue forming the tissue site, the type of injury or wound (if present), the medical condition of the patient, and the preference of the attending physician. After selecting the desired target pressure, the controller 130 can operate the negative pressure source 105 in one or more control modes based on the target pressure and can receive feedback from one or more sensors to maintain the target pressure at the tissue interface 120.

[0051] In some embodiments, the controller 130 may have a continuous pressure mode, in which the negative pressure source 105 is operated to provide a constant target negative pressure for the duration of the treatment or until manually stopped. Additionally, or alternatively, the controller may have an intermittent pressure mode. In some exemplary embodiments, the controller 130 can operate the negative pressure source 105 to cycle between the target pressure and atmospheric pressure. For example, the target pressure may be set to a value of 135 mmHg for a specified period (e.g., 5 minutes), followed by a specified period of pause (e.g., 2 minutes). This cycle can be repeated by operating the negative pressure source 105 to form a square wave pattern between the target pressure and atmospheric pressure.

[0052] In some exemplary embodiments, the increase in negative pressure from the ambient pressure to the target pressure may not be instantaneous. For example, the negative pressure source 105 and the dressing material 110 can have an initial rise time. The initial rise time can vary depending on the type of dressing material and treatment device used. For example, the initial rise time for one therapy system may be in the range of about 20 - 30 mmHg / second, and for another therapy system, it may be in the range of about 5 - 10 mmHg / second. When the therapy system 100 is operating in the intermittent mode, the repeated rise time may be a value substantially equal to the initial rise time.

[0053] In some exemplary dynamic pressure control modes, the target pressure can change over time. For example, the target pressure may change in the form of a triangular waveform that varies between a negative pressure of 50 - 135 mmHg with a rising rate of negative pressure set at +25 mmHg / min and a falling rate set at -25 mmHg / min. In other embodiments of the therapy system 100, the triangular waveform can vary between a negative pressure of 25 - 135 mmHg with a rising rate and a falling rate of about +30 mmHg / min or about -30 mmHg / min.

[0054] In some embodiments, the controller 130 may control or determine a variable target pressure in the dynamic pressure mode, and the variable target pressure may vary between a maximum pressure value and a minimum pressure value that can be set as an input defined by the operator as a desired negative pressure range. The variable target pressure may also be processed and controlled by the controller 130 to vary the target pressure according to a predetermined waveform such as a triangular waveform, a sine waveform, or a sawtooth waveform. In some embodiments, the waveform may be set by the operator as a predetermined or time-varying negative pressure desired for treatment.

[0055] In some embodiments, the controller 130 may receive and process data such as data related to the infusion solution provided to the tissue interface 120. Such data may include the type of infusion solution prescribed by the clinician, the volume of fluid or solution infused into the tissue site ("fill volume"), and the amount of time defined to leave the solution at the tissue site before applying negative pressure to the tissue site ("dwell time"). The fill volume may be, for example, 10 to 500 mL, and the dwell time may be 1 second to 30 minutes. The controller 130 may also control the operation of one or more components of the therapy system 100 with respect to the infusion solution. For example, the controller 130 may manage the fluid dispensed from the solution source 145 to the tissue interface 120. In some embodiments, the fluid may be infused into the tissue site by applying a negative pressure from the negative pressure source 105 to reduce the pressure at the tissue site and drawing the solution into the tissue interface 120. In some embodiments, the solution can be infused into the tissue site by applying a positive pressure from the positive pressure source 150 to move the solution from the solution source 145 to the tissue interface 120. Additionally, or alternatively, the solution source 145 may be raised to a height sufficient to allow gravity to move the solution to the tissue interface 120.

[0056] The controller 130 may also control the drip hydrodynamics at 425 by providing a continuous flow or an intermittent flow of the solution. A negative pressure may be applied to provide either a continuous flow or an intermittent flow of the solution. The application of the negative pressure may be implemented to provide a continuous pressure operation mode for achieving a continuous flow rate of the drip solution through the tissue interface 120, or may be implemented to provide a dynamic pressure operation mode for varying the flow rate of the drip solution through the tissue interface 120. Alternatively, the application of the negative pressure may be implemented to provide an intermittent operation mode that allows the drip solution to dwell at the tissue interface 120. In the intermittent mode, for example, a specific fill volume and dwell time may be provided depending on the type of tissue site being treated and the type of dressing material being utilized. A negative pressure treatment may be applied after or during the dripping of the solution. The controller 130 can be utilized to select the operation mode and the duration of the negative pressure treatment before initiating another drip cycle by dripping more solution.

[0057] FIG. 2 is an exploded view of an example of the dressing material 110 of FIG. 1, showing further details that may be associated with some embodiments. The dressing material 110 can include a sealing layer or wound contact layer 202, a first film layer 204, a manifold layer or manifold 206, a second film layer 208, and a drape or cover 125. The wound contact layer 202 can be formed from a flexible and bendable material suitable for providing a fluid seal with the tissue site, such as a suitable gel material, and may have a substantially flat surface. In some embodiments, the wound contact layer 202 can include, but is not limited to, silicone gel, soft silicone, hydrocolloid, hydrogel, polyurethane gel, polyolefin gel, hydrogenated styrene copolymer gel, foamed gel, a soft closed-cell foam such as polyurethane and polyolefin coated with an adhesive, polyurethane, polyolefin, or hydrogenated styrene copolymer. In some embodiments, the wound contact layer 202 may have a thickness in the range of about 200 micrometers to about 1,000 micrometers. In some embodiments, the wound contact layer 202 can be formed from a hydrophobic or hydrophilic material.

[0058] In some embodiments, the wound contact layer 202 can include or be formed from a hydrophobic or hydrophobic-coated material. For example, the wound contact layer 202 can be formed by coating a spaced material such as a woven mesh, non-woven mesh, molded mesh, or extruded mesh with a hydrophobic material such as soft silicone.

[0059] The wound contact layer 202 can have a first surface 210 and a second surface 212 opposite the first surface 210. The wound contact layer 202 may also include a peripheral portion or periphery 214 defined by the outer periphery of the wound contact layer 202, and a central portion 215 including a treatment opening 216 formed through the wound contact layer 202. In some embodiments, the treatment opening 216 may have a complementary or corresponding contour to the outer periphery of the manifold 206. The wound contact layer 202 may also include a plurality of openings 218 formed through the wound contact layer 202. In some embodiments, the plurality of openings 218 can be formed through a region of the wound contact layer 202 between the treatment opening 216 and the periphery 214.

[0060] In some embodiments, the perimeter 214 of the wound contact layer 202 may be or include a sensor 220. The sensor 220 can be configured to change color to indicate a sensed parameter when the sensor 220 is acted upon by a light source. For example, in some embodiments, the sensor 220 can be configured to sense an oxygen level. When acted upon by a light source, the sensor 220 can change color. In some embodiments, the intensity of the color can depend on a sensed parameter such as the sensed oxygen level. For example, the sensor 220 may emit a strong light or a strong color when the sensed oxygen level is relatively low, and the sensor 220 may emit a relatively dull or dim light or color when the sensed oxygen level is relatively high. In some embodiments, the sensor 220 may emit a reference level color when exposed to the ambient environment. Thus, when the sensor 220 senses an oxygen level lower than the oxygen level of the ambient environment, the sensor 220 can emit a color that is stronger or more vivid than the reference level color. When the sensor 220 senses an oxygen level higher than the oxygen level of the ambient environment, the sensor 220 can emit a color that is less intense or less vivid than the reference level color. In other embodiments, the sensor 220 may emit light differently than described above, but may still change when exposed to a light source such that the sensed parameter is displayed by the sensor 220. In some embodiments, the sensor 220 can be configured to sense other parameters such as wound temperature, pH level, or the presence of a fluid. In embodiments where the sensor 220 is configured to sense a pH level, the sensor 220 can function substantially as described above with respect to oxygen sensing. For example, the intensity of the emitted light can depend on the sensed pH level. In embodiments where the sensor 220 is configured to detect the presence of a fluid, the sensor 220 may be partially or completely opaque when dry and transparent when exposed to the fluid. When the sensor 220 transitions from opaque to transparent, the sensor 220 is detecting the presence of the fluid.

[0061] In some embodiments, sensor 220 may be a dye that can be integrated or blended into dressing material 110. For example, in some embodiments, sensor 220 can be integrated into the periphery 214 of wound contact layer 202. In other embodiments, sensor 220 may be a film containing a luminescent material such as a transition metal ligand or a chemosensing material. The chemosensing material may be, in some embodiments, an oxygen sensing material or molecule, or a pH sensing material or molecule. The film can be bonded or deposited onto a layer of dressing material 110 such as wound contact layer 202. In some embodiments, sensor 220 may be an oxygen sensing film. The oxygen sensing film can include a polymer matrix in which an oxygen sensing molecule is dissolved. Biocompatible silicone and a biocompatible oxygen sensing material can be mixed or blended with a transparent medical grade polymer to create a desired oxygen sensing film. In some embodiments, the oxygen sensing molecule may be a porphyrin. The oxygen sensing film can include either a low oxygen permeability polymer or a high oxygen permeability polymer. The low oxygen permeability polymer can include at least one of polyvinyl alcohol, ethylene vinyl alcohol, polyacrylonitrile, polyvinylidene chloride, or another similar material. The high oxygen permeability polymer can include at least one of silicone, polyolefin elastomer, or another similar material. In other embodiments, sensor 220 may be a biocompatible oxygen sensing material such as the above-described porphyrin directly printed onto a layer of dressing material 110 such as wound contact layer 202.

[0062] As shown in FIG. 2, the sensor 220 is deposited on the second surface 212 of the wound contact layer 202. In some embodiments, the sensor 220 may extend around the periphery 214 of the wound contact layer 202, and in other embodiments, the sensor 220 can be deposited over the entire second surface 212 of the wound contact layer 202. In still other embodiments, the sensor 220 can be deposited at individual locations on the second surface 212 of the wound contact layer 202. The sensor 220 may be located at any position on the second surface 212 of the wound contact layer 202 that is proximate to the wound perimeter region of the tissue site when the dressing 110 is placed on the tissue site. When the dressing 110 is placed on the tissue site, the sensor 220 can be configured to sense parameters in the wound perimeter region of the wound where the wound contact layer 202 is attached to the tissue site. For example, the sensor 220 can be configured to sense the oxygen level in the wound perimeter region of the tissue site when the dressing 110 is attached to the tissue site.

[0063] In some embodiments, the plurality of apertures 218 can be formed by cutting, punching, or applying local radio frequency or ultrasonic energy through the wound contact layer 202. In some embodiments, the plurality of apertures 218 can be formed by other suitable techniques for forming openings or perforations in the wound contact layer 202. In some embodiments, the plurality of apertures 218 may have a uniform distribution pattern. In other embodiments, the plurality of apertures 218 may be randomly distributed. In some embodiments, the plurality of apertures 218 may have many arbitrary combinations of shapes including circular, square, star, oval, polygonal, slit, complex curve, linear, or triangular.

[0064] In some embodiments, each of the plurality of apertures 218 may have uniform or similar geometric properties. For example, each of the plurality of apertures 218 may be a circular aperture and may have substantially the same diameter. In some embodiments, each of the plurality of apertures 218 may have a diameter in the range of about 1 millimeter to about 20 millimeters.

[0065] In some embodiments, the geometric properties of the plurality of apertures 218 may vary. For example, the diameter of the plurality of apertures 218 may vary according to the arrangement of the apertures 218 in the wound contact layer 202. In some embodiments, at least some of the plurality of apertures 218 may have a diameter in the range of about 5 millimeters to about 10 millimeters. In some embodiments, at least some of the plurality of apertures 218 may have a diameter in the range of about 7 millimeters to about 9 millimeters. In some embodiments, the wound contact layer 202 may include corners, and the plurality of apertures 218 disposed at or near the corners may have a diameter in the range of about 7 millimeters to about 8 millimeters.

[0066] In some embodiments, at least some of the plurality of apertures 218 disposed adjacent to the periphery 214 may be cut or exposed at the periphery 214 and have an interior that laterally communicates (with respect to the first surface 210 and / or the second surface 212) laterally. In some embodiments, the lateral direction may be in the same plane as the first surface 210 and / or the second surface 212 and extend toward the periphery 214. In some embodiments, at least some of the plurality of apertures 218 disposed adjacent to or at the periphery 214 may be substantially equally spaced around the periphery 214. Alternatively, in some embodiments, the spacing between the plurality of apertures 218 adjacent to or at the periphery 214 may be irregularly spaced.

[0067] The first film layer 204 can include a structure suitable for controlling or managing fluid flow. In some embodiments, the first film layer 204 may be a fluid control layer comprising a liquid-impermeable, vapor-permeable elastomeric material. In some embodiments, the first film layer 204 can be formed from a polymer film or may include a polymer film. For example, in some embodiments, the first film layer 204 can be formed from, or may include, a polyolefin film such as a polyethylene film. In some embodiments, the first film layer 204 may be substantially clear or optically transparent. In some embodiments, the first film layer 204 can be formed from, or may include, the same material as the cover 125. In some embodiments, the first film layer 204 can be formed from, or may include, a biocompatible polyurethane film that has been tested and certified according to the USP Class VI standard. In some embodiments, the first film layer 204 may also have a smooth or matte surface texture. In some embodiments, the first film layer 204 may have a finish or gloss finish of grade B3 or higher according to the Society of Plastics Industry (SPI) standard. In some embodiments, the surface of the first film layer 204 may be a substantially flat surface having a height variation in the range of about 0.2 millimeters to about 1 centimeter.

[0068] In some embodiments, the first film layer 204 may be hydrophobic. The hydrophobicity of the first film layer 204 can vary, but in some examples, it can have a contact angle with water of at least 90 degrees. In some embodiments, the first film layer 204 may have a contact angle with water of 150 degrees or less. In some embodiments, the first film layer 204 can have a contact angle with water in the range of about 90 degrees to about 120 degrees, or in the range of about 120 degrees to about 150 degrees. The water contact angle can be measured using any standard apparatus. A manual goniometer can be used to visually approximate the contact angle, but contact angle measuring equipment often involves an integrated system that includes a leveling stage, a liquid dropper (such as a syringe), a camera, and software designed to calculate the contact angle more accurately and precisely. Non-limiting examples of such integrated systems include the FTÅ125, FTÅ200, FTÅ2000, and FTÅ4000 systems, all commercially available from First Ten Angstroms, Inc. (Portsmouth, Virginia), and the DTA25, DTA30, and DTA100 systems, all commercially available from Kruss GmbH (Hamburg, Germany). Unless otherwise specified, the water contact angle herein is measured using deionized water and / or distilled water on a horizontal sample surface for droplets added from a height of 5 centimeters or less in air at 20 - 25°C and a relative humidity of 20 - 50%. The contact angle herein represents the average of 5 - 9 measurements, and the highest and lowest measurement values are discarded. In some embodiments, the hydrophobicity of the first film layer 204 can be further enhanced with hydrophobic coatings of other materials such as silicone and fluorocarbon.

[0069] The first film layer 204 may also be suitable for welding to other layers including the manifold 206 and the second film layer 208. In some embodiments, the first film layer 204 may be adapted to weld to polymers such as polyurethanes, polyurethane films, and polyurethane foams using heat welding, radio-frequency (RF) welding, ultrasonic welding, or other methods. RF welding can be particularly suitable for more polar materials such as polyurethanes, polyamides, polyesters, and acrylates. A sacrificial polar interface can be used to facilitate RF welding of less polar film materials such as polyethylene.

[0070] The areal density of the first film layer 204 may vary depending on the particular therapy or application. In some embodiments, an areal density of less than 40 grams per square meter may be suitable. In some embodiments, the areal density of the first film layer 204 may range from about 20 grams per square meter to about 30 grams per square meter.

[0071] In some embodiments, the first film layer 204 can be formed from, or can include, a hydrophobic polymer such as a polyethylene film. The simple and inert structure of polyethylene provides a surface that interacts little, if at all, with biological tissues and body fluids, can promote free flow of liquids, and provides a surface with low adhesiveness to tissues and body fluids, and this property can be particularly advantageous for many applications. In some embodiments, the first film layer 204 can be formed from other polymer films such as polyurethane, acrylic, polyolefin (such as cyclic olefin copolymer), polyacetate, polyamide, polyester, copolyester, PEBAX block copolymer, thermoplastic elastomer, thermoplastic vulcanizate, polyether, polyvinyl alcohol, polypropylene, polymethylpentene, polycarbonate styrene, silicone, fluoropolymer, and acetate. In some embodiments, the first film layer 204 can have a thickness in the range of about 20 micrometers to about 500 micrometers. In some embodiments, the first film layer 204 can have a thickness of about 23 micrometers, about 25 micrometers, about 100 micrometers, about 250 micrometers, about 300 micrometers, and about 500 micrometers. In some embodiments, the first film layer 204 can include a polar film suitable for lamination to a polyethylene film, such as polyamide, copolyester, ionomer, and acrylic. In some embodiments, the first film layer 204 may include a bonding layer to improve the bond between the polyethylene and the polar film layer. In some embodiments, the bonding layer may include ethylene vinyl acetate or modified polyurethane. In some embodiments, the first film layer 204 can include an ethyl methyl acrylate (EMA) film.

[0072] The first film layer 204 can have a first surface 222 and a second surface 224 opposite the first surface 222. The first film layer 204 can further include a perimeter 226 defined by the outer perimeter of the first film layer 204. In some embodiments, the perimeter 226 may be in a stadium shape, a disco rectangle shape, or an obround shape. The first film layer 204 may also include one or more fluid passages 228 formed through the first film layer 204, which can be distributed uniformly or randomly across the first film layer 204.

[0073] In some embodiments, the fluid passages 228 may function as bidirectional and fluid-responsive valves. For example, each fluid passage 228 is not normally pulled to prevent or substantially reduce the flow of fluid across the fluid passage 228, and expands or opens to allow the flow of fluid across the fluid passage 228 in response to a pressure gradient applied across the fluid passage 228, and may be an elastic passage. In some embodiments, the fluid passages 228 can include perforations formed in the first film layer 204. The perforations can be formed by removing material from the first film layer 204 or by cutting the first film layer 204. In some embodiments, cutting the first film layer 204 can deform the edges of the perforations. In some embodiments, the fluid passages 228 may be narrow enough to form a seal or fluid restriction to substantially reduce or prevent the flow of fluid across the fluid passage 228, especially when there is no pressure differential. In some embodiments, one or more of the fluid passages 228 may be an elastomeric valve that is normally closed when not pulled to prevent the flow of liquid across the valve and can open in response to a pressure gradient. In some embodiments, the fluid passages 228 may include open windows formed through the first film layer 204. The open windows can be formed by removing material from the first film layer 204, but the amount of material removed and the resulting dimensions of the open windows can be up to one order of magnitude smaller than the perforations and may not deform the edges.

[0074] In some embodiments, the fluid passage 228 may include one or more slits, slots, or combinations of slits and slots in the first film layer 204. In some embodiments, the fluid passage 228 can include a linear slot having a length of less than about 5 millimeters and a width of less than about 2 millimeters. In some embodiments, the length may be at least about 2 millimeters, and the width may be at least about 0.5 millimeters. In some embodiments, the length may range from about 2 millimeters to about 5 millimeters, the width may range from about 0.5 millimeters to about 2 millimeters, and the tolerance is about 0.1 millimeter. In some embodiments, the length may be about 3 millimeters. Such dimensions and tolerances can be achieved, for example, using a laser cutter. In some embodiments, slots of such a configuration can function as an imperfect valve that substantially reduces liquid flow in a normally closed or stationary state. Such slots may form a flow restriction without being completely closed or sealed. The slot can expand or open wider in response to a pressure gradient applied across the slot, allowing increased liquid flow through the slot.

[0075] In some embodiments, the fluid passage 228 may include a linear slit having a length of less than about 5 millimeters. In some embodiments, the length of the linear slit may be at least about 2 millimeters. In some embodiments, the length of the linear slit may range from about 2 millimeters to about 5 millimeters, and the tolerance is about 0.1 millimeter. In some embodiments, the length of the linear slit may be about 3 millimeters.

[0076] In some embodiments, although not shown herein, the first film layer 204 may be integral with the wound contact layer 202. For example, the wound contact layer 202 may not include the treatment opening 216 and may be a continuous layer. The central portion 215 of the wound contact layer 202 may include the fluid passage 228 of the first film layer in some embodiments.

[0077] In some embodiments, the manifold 206 can be formed as a substantially sheet-like structure having a first surface 232 and a second surface 234 opposite the first surface 232. In some embodiments, the manifold 206 can further include a periphery 236 defined by the outer periphery of the manifold 206. In some embodiments, the periphery 236 of the manifold 206 may be substantially similar to the periphery 226 of the first film layer 204 or may have the same extent. In some embodiments, the manifold 206 can be formed from a polyurethane sheet such as a vacuum-formed sheet of polyurethane having a thickness of about 0.5 millimeters. In some embodiments, the manifold 206 can be formed from a polymeric material that is substantially clear or optically transparent, enabling a user to see through the manifold 206.

[0078] In some embodiments, the plurality of windows 238 may be removed from the manifold 206 to form a grid pattern. For example, the plurality of windows 238 can be arranged in a row and column pattern. The center of each window 238 of the plurality of windows 238 may be aligned with the centers of the other windows 238 of the plurality of windows 238 within a row, and the center of each window 238 of the plurality of windows 238 may be aligned with the centers of the other windows 238 of the plurality of windows 238 within a column. In some embodiments, the plurality of standoffs 240 can be formed on the second surface 234 of the manifold 206. In some embodiments, the plurality of standoffs 240 may form a grid pattern. For example, the plurality of standoffs 240 can be arranged in a row and column pattern. The center of each standoff 240 of the plurality of standoffs 240 may be aligned with the centers of the other standoffs 240 of the plurality of standoffs 240 within a row, and the center of each standoff 240 of the plurality of standoffs 240 may be aligned with the centers of the other standoffs 240 of the plurality of standoffs 240 within a column. In some embodiments, each row of the plurality of windows 238 can be arranged adjacent to a row of the plurality of standoffs 240, and each column of the plurality of windows 238 can be arranged adjacent to a column of the plurality of standoffs 240. In some embodiments, the plurality of windows 238 and the plurality of standoffs 240 can be arranged in a pattern such that the rows of the pattern alternate between the rows of the plurality of windows 238 and the rows of the plurality of standoffs 240, and the columns of the pattern alternate between the columns of the plurality of windows 238 and the columns of the plurality of standoffs 240.

[0079] In some embodiments, each window 238 may have a profile that is substantially circular in the plane of the first surface 232 of the manifold 206. In some embodiments, each standoff 240 may have a profile that is substantially circular and may project outwardly substantially perpendicular to the plane of the second surface 234 of the manifold 206. In some embodiments, the diameter of each window 238 of the plurality of windows 238 may be greater than the diameter of each standoff 240 of the plurality of standoffs 240. For example, each window 238 of the plurality of windows 238 may have a diameter of about 8 millimeters, and each standoff 240 of the plurality of standoffs 240 may have a diameter of about 3 millimeters. In some embodiments, each standoff 240 of the plurality of standoffs 240 may have a height in the range of about 0.5 millimeter to about 3 millimeters. In some embodiments, each standoff 240 of the plurality of standoffs 240 may have a height of about 2.5 millimeters. In some embodiments, each standoff 240 of the plurality of standoffs 240 may have a height of about 3 millimeters. In some embodiments, each standoff 240 of the plurality of standoffs 240 within a row may be spaced apart from an adjacent standoff 240 of the plurality of standoffs 240 within the row by a distance of about 4 millimeters from the center, and each standoff 240 of the plurality of standoffs 240 within a column may be spaced apart from an adjacent standoff 240 of the plurality of standoffs 240 within the column by a distance of about 4 millimeters from the center. In some embodiments, the plurality of standoffs 240 may be straight circular cylinders having hemispherical ends such as half capsules, may be formed on the second surface 234 of the manifold 206, and may project away from the second surface 234 in a direction substantially perpendicular to the second surface 234. In some embodiments, each of the plurality of standoffs 240 may have a height in the range of about 2.5 millimeters to about 3 millimeters.

[0080] In some embodiments, the manifold 206 can include a raised portion, such as a lip portion or a boss 242. In some embodiments, the boss 242 may project substantially perpendicular outward from the plane of the first surface 232 of the manifold 206. In some embodiments, the boss 242 may have a reduced profile or contour similar to the shape of the periphery 236 of the manifold 206. In some embodiments, the manifold 206 may also have a boundary region 244 between the boss 242 and the periphery 236 of the manifold. In some embodiments, the boundary region 244 may not include either the window 238 of the plurality of windows 238 or the standoff 240 of the plurality of standoffs 240.

[0081] The second film layer 208 can have a first surface 250 and a second surface 252 opposite the first surface 250. The second film layer 208 can further include a periphery 254 defined by the perimeter of the second film layer 208. A negative pressure opening, such as the opening 256, can be formed through the second film layer 208. In some embodiments, the second film layer 208 can be formed of, or can include, any of the materials described above with respect to the cover 125 and / or the first film layer 204.

[0082] The cover 125 can include a first surface 262 and a second surface 264 opposite the first surface 262. The cover 125 can further include a peripheral portion or periphery 266 defined by the outer perimeter of the cover 125. In some embodiments, the cover may have a central portion 267 having a central opening 268 formed therethrough. In some embodiments, the cover 125 may act as a barrier between the ambient environment and the sensor 220. For example, the cover 125 may be substantially oxygen impermeable to prevent any oxygen from reaching the sensor 220 and affecting the oxygen levels sensed in the tissue site wound perimeter region.

[0083] In some embodiments, although not shown herein, the central opening 268 of the second film layer 208 and the cover 125 may be omitted, and the cover 125 may be a continuous layer such that the second surface 264 of the cover 125 contacts the first surface 232 of the manifold 206. In other embodiments, the second film layer 208 may be a part of the cover 125 and may be aligned with the central opening 268 of the cover 125 so as to create a barrier between the surrounding environment and the remaining portion of the dressing material 110.

[0084] In some embodiments, the periphery 214 of the wound contact layer 202 may have a spread that is substantially the same as the periphery 266 of the cover 125. In some embodiments, the periphery 226 of the first film layer 204, the periphery 236 of the manifold 206, and the periphery 254 of the second film layer 208 may have a substantially the same spread. In some embodiments, the contour of the treatment opening 216 of the wound contact layer 202 may have a spread that is substantially the same as the contour of the central opening 268 of the cover 125. In some embodiments, the contours of the treatment opening 216 and the central opening 268 may be substantially similar to the contours of the periphery 226 of the first film layer 204, the periphery 236 of the manifold 206, and the periphery 254 of the second film layer 208. In some embodiments, the contours of the treatment opening 216 and the central opening 268 may be substantially similar to the contours of the periphery 226 of the first film layer 204, the periphery 236 of the manifold 206, and the periphery 254 of the second film layer 208, but may be reduced. In the assembled form, the wound contact layer 202, the first film layer 204, the manifold 206, the second film layer 208, and the cover 125 may be laminated such that the periphery 214 of the wound contact layer 202 is aligned with the periphery 266 of the cover 125 and the periphery 226 of the first film layer 204 is aligned with the periphery 236 of the manifold 206 and the periphery 254 of the second film layer 208. In some embodiments, the treatment opening 216 may be aligned with the central opening 268, and the periphery 226 of the first film layer 204, the periphery 236 of the manifold 206, and the periphery 254 of the second film layer 208 may be arranged such that they are aligned with and extend evenly beyond the contours of the treatment opening 216 and the central opening 268.

[0085] In some embodiments, a portion of the first surface 210 of the wound contact layer 202 around the treatment opening 216 can be coupled to a portion of the second surface 224 of the first film layer 204 near the periphery 226, and a portion of the second surface 264 of the cover 125 around the central opening 268 can be coupled to a portion of the first surface 250 of the second film layer 208 near the periphery 254. In some embodiments, a portion of the first surface 210 of the wound contact layer 202 between the periphery 214 and the treatment opening 216 can be coupled to a portion of the second surface 264 of the cover 125 between the periphery 266 and the central opening 268.

[0086] Some examples of the dressing 110 may also include a dressing interface 270 and a fluid conduit 272. In various implementations, the fluid conduit 272 may be a flexible tube that can be fluidly coupled at one end to the dressing interface 270. In various implementations, the dressing interface 270 may be an elbow connector that can be disposed over the opening 256 to provide a fluid path between the fluid conduit 272 and the interior of the dressing 110.

[0087] In some embodiments, the dressing material 110 may further include a release liner 278 to protect the wound contact layer 202 and the adhesive coated on the second surface 264 of the cover 125 prior to use. The release liner 278 can also provide rigidity, for example, to assist in the deployment of the dressing material 110. In various implementations, the release liner may include polyethylene terephthalate (PET) or a similar polar semi-crystalline polymer. The use of a polar semi-crystalline polymer for the release liner 278 can substantially eliminate wrinkles or other deformations of the dressing material 110. The polar semi-crystalline polymer can be highly oriented and can have resistance to softening, swelling, or other deformations that can occur when an object contacts the layers and / or components of the dressing material 110, or when the dressing material 110 is subjected to temperature or environmental changes, or during sterilization. Further, the release agent can be disposed on the first surface 280 of the release liner 278 configured to contact the adhesive disposed on the second surface 212 of the wound contact layer 202 and the second surface 264 of the cover 125. For example, the release agent may be a silicone coating and can have a release element suitable for facilitating the removal of the release liner 278 without damaging or deforming the dressing material 110 by hand. In various implementations, the release agent may be a fluorocarbon or a fluorosilicone. In various implementations, the release liner 278 may not be coated or may be used otherwise without a release agent.

[0088] Figure 3 is a perspective view of an assembled example of the dressing material 110 of Figure 2. In some exemplary embodiments, the cover 125, the second film layer 208, the manifold 206, the first film layer 204, and / or the wound contact layer 202 may be substantially clear or optically transparent, enabling visualization of the layers of the dressing material 110 and visualization through the window 238 of the manifold 206. The sensor 220 may also be visible through the cover 125 in some embodiments such that when the dressing material 110 is actuated by a light source, light or color can be observed through the cover 125 and the wound contact layer 202.

[0089] Figure 4 is a cross-sectional view showing the dressing material 110 of Figure 3 taken along line 4-4, which is applied to the tissue site 402 and shows further details associated with the therapy system 100 of Figure 1. In some embodiments, the second surface 264 of the cover 125 may be coated with an adhesive layer 404, and at least a portion of the cover 125 can be bonded to at least a portion of the first surface 210 of the wound contact layer 202 using the adhesive layer 404. The adhesive layer 404 may be any of the attachment devices described above with reference to Figure 1. In some embodiments, a portion of the second surface 264 of the cover 125 can be bonded by the adhesive layer 404, for example at the periphery 254, to a portion of the first surface 250 of the second film layer 208.

[0090] In some applications, the dressing material 110 may be applied to the tissue site 402 to cover the wound 406. The tissue site 402 may be or may include a defect or target treatment site such as the wound 406, which may be partially or completely filled or covered by the dressing material 110. In some embodiments, the wound 406 may be in the epidermis 408. In some embodiments, the wound 406 may extend into the dermis 410 through the epidermis 408. In other embodiments, the wound 406 may extend into the subcutaneous tissue 412 through the epidermis 408 and the dermis 410. In some embodiments, at least a portion of the second surface 212 of the wound contact layer 202 may be contacted with a portion of the epidermis 408 surrounding the wound, such as the wound perimeter region 414. At least a portion of the second surface 224 of the first film layer 204 may be disposed within, covering, over, against, or otherwise in proximity to the wound 406.

[0091] During operation, negative pressure may be provided to the wound 406 and / or fluid may be removed from the wound 406 by the negative pressure source 105 of the therapy unit 160 through the dressing interface 270 and the fluid conduit 272. While the dressing material 110 is applied to the tissue site 402, the sensor 220 may be in contact with the wound perimeter region 414. The sensor 220 may be configured to detect a parameter in the wound perimeter region 414. For example, the sensor 220 may be configured to detect the oxygen level in the wound perimeter region 414. In other embodiments, the sensor 220 may be configured to detect another parameter such as pH or fluid level in the wound perimeter region 414.

[0092] FIG. 5A shows a perspective view of another example of the dressing 110 of FIG. 1, showing further details that may be associated with some embodiments. Similar to FIG. 3, the cover 125, the second film layer 208, the manifold 206, the first film layer 204, and / or the wound contact layer 202 may be substantially clear or optically transparent, enabling visualization of the layers of the dressing 110 and visualization through the window 238 of the manifold 206.

[0093] The dressing 110 may include a periwound sensor 502. In some embodiments, the periwound sensor 502 can be disposed on or within the wound contact layer 202. For example, in some embodiments, the periwound sensor 502 can be disposed between the second surface 264 of the cover 125 and the first surface 210 of the wound contact layer 202. In other embodiments, the periwound sensor 502 can be combined or blended within the wound contact layer 202, or disposed proximate to the second surface 212 of the wound contact layer 202. The periwound sensor 502 may be similar or equivalent to the sensor 220 described above. For example, the periwound sensor 502 can be configured to sense parameters in the periwound region of the tissue site, such as the oxygen level in the periwound region 414 of the tissue site 402.

[0094] In some embodiments, the dressing 110 may further include at least one wound sensor 504. In some embodiments, the wound sensor 504 can be disposed between the second surface 252 of the second film layer 208 and the first surface 232 of the manifold 206. In other embodiments, the wound sensor 504 can be disposed at different locations within the dressing 110, but still proximate to a wound of the tissue site, such as the wound 406 of the tissue site 402. The wound sensor 504 may be similar or equivalent to the sensor 220 described above. For example, the wound sensor 504 can be configured to sense parameters in the wound of the tissue site, such as the oxygen level in the wound 406 of the tissue site 402.

[0095] Referring to FIG. 5B, another embodiment of the dressing material 110 of FIG. 5A is shown. The dressing material 110 may be similar to the dressing material 110 of FIG. 5A, but may further include a wound perimeter sensor cover 510 and a wound sensor cover 512. The wound perimeter sensor cover 510 and the wound sensor cover 512 may be substantially clear or optically transparent, enabling visualization of the dressing material 110 through the wound perimeter sensor cover 510 and the wound sensor cover 512. The wound perimeter sensor cover 510 can be coupled or integrated to the cover 125 and can be disposed proximate to the wound perimeter sensor 502. The wound perimeter sensor cover 510 can be removably coupled to the cover 125 such that each of the wound perimeter sensor covers 510 can be removed to expose one of the wound perimeter sensors 502 within the dressing material 110.

[0096] In some embodiments, the wound sensor cover 512 can be coupled or integrated to the second film layer 208 and can be disposed proximate to the wound sensor 504. The wound sensor cover 512 can be removably coupled to the second film layer 208 such that the wound sensor cover can be removed to expose the wound sensor 504 within the dressing material 110.

[0097] In some embodiments, the periwound sensor cover 510 and the wound sensor cover 512 may be included in the dressing 110 such that the periwound sensor 502 and the wound sensor 504 can be added to or removed from the dressing 110 while the dressing 110 is deployed to a tissue site such as the tissue site 402. The periwound sensor cover 510 and the wound sensor cover 512 may be impermeable to both water vapor and liquid to provide a fluid seal with the cover 125 and the second film layer 208, respectively. The periwound sensor cover 510 and the wound sensor cover 512 may isolate the periwound sensor 502 and the wound sensor 504 from the external or ambient environment such that the periwound sensor 502 and the wound sensor 504 can sense parameters in the periwound region 414 and the wound 406 of the tissue site 402.

[0098] FIG. 5C is a cross-sectional view of the dressing 110 taken along line 5C-5C. The periwound sensor 502 can be disposed within the wound contact layer 202, and the periwound sensor cover 510 can be coupled to the cover 125. The periwound sensor cover 510 may include a flap 520. The flap 520 can enable a healthcare provider or another user to easily remove the periwound sensor cover 510 from the dressing 110. When the periwound sensor cover 510 is removed from the dressing 110, the periwound sensor 502 may be accessible through the cover 125.

[0099] FIG. 5D is a cross-sectional view of the dressing 110 taken along line 5D-5D. The wound sensor 504 can be disposed adjacent to the first surface 232 of the manifold 206. In other embodiments, the wound sensor 504 can be disposed at a different location, such as within one of the plurality of windows 238 of the manifold 206. The wound sensor cover 512 can be coupled to the second film layer 208. The wound sensor cover 512 can include a flap 522 similar to the flap 520 of the periwound sensor cover 510.

[0100] Figures 6A-6F are cross-sectional views of dressing material 110 showing wound perimeter sensors 502 disposed at different locations within dressing material 110. FIG. 6A shows wound perimeter sensor 502 disposed within one of a plurality of openings 218 of wound contact layer 202. When dressing material 110 is disposed at a tissue site such as tissue site 402, wound perimeter sensor 502 can be in direct contact with the wound perimeter region 414 of tissue site 402.

[0101] FIG. 6B shows wound perimeter sensor 502 molded or blended into wound contact layer 202. Wound perimeter sensor 502 may be separated from the plurality of openings 218 and may be in direct contact with the wound perimeter region 414 of tissue site 402 when dressing material 110 is disposed at tissue site 402.

[0102] FIG. 6C shows wound perimeter sensor 502 disposed proximate the first surface 210 of wound contact layer 202. Wound perimeter sensor 502 can be disposed proximate one of the plurality of openings 218 but may be separated from the wound perimeter region 414 of tissue site 402 when dressing material 110 is disposed at tissue site 402.

[0103] FIG. 6D shows wound perimeter sensor 502 disposed between the first surface 210 of wound contact layer 202 and the second surface 264 of cover 125. Wound perimeter sensor 502 may be separated from the plurality of openings 218 such that wound perimeter sensor 502 is isolated from the wound perimeter region 414 of tissue site 402 when dressing material 110 is disposed at tissue site 402.

[0104] FIG. 6E shows a wound perimeter sensor 502 coupled to a first surface 262 of a cover 125 on an opposite side of one of a plurality of apertures 218 of the wound contact layer 202. A portion 602 of the cover 125 can be disposed within one of the plurality of apertures 218 such that a first surface 604 of the wound perimeter sensor 502 is coplanar with the first surface 262 of the cover 125. In some embodiments, the wound perimeter sensor 502 is isolated from the wound perimeter region 414 of the tissue site 402 and can provide a baseline or ambient oxygen level reading when the sensor is actuated by a light source. In some embodiments, a plurality of wound perimeter sensors 502 can be used such that parameters can be measured at multiple locations using the wound perimeter sensors 502.

[0105] FIG. 6F shows a wound perimeter sensor 502 coupled to a first surface 262 of a cover 125 on an opposite side of one of a plurality of apertures 218 of the wound contact layer 202. Similar to the wound perimeter sensor 502 shown in FIG. 6E, the wound perimeter sensor 502 is isolated from the wound perimeter region 414 of the tissue site 402 and can provide a baseline or ambient oxygen level reading when the sensor is actuated by a light source. In some embodiments, a plurality of wound perimeter sensors 502 can be used such that parameters can be measured at multiple locations using the wound perimeter sensors 502.

[0106] FIGS. 7A-7F are cross-sectional views of the dressing 110 showing wound sensors 504 disposed at different locations within the dressing 110. FIG. 7A shows a wound sensor 504 coupled to a second surface 224 of the first film layer 204. The first film layer 204 proximate the wound sensor 504 is coupled to at least one of a plurality of standoffs 240 and a second surface 234 of the manifold 206 such that the first surface 222 of the first film layer 204, and thereby the wound sensor 504, can be pushed into the manifold 206 such that the wound sensor 504 is coplanar with the second surface 224 of the first film layer 204. When the dressing 110 is disposed on the tissue site 402, the wound sensor 504 can be in direct contact with the wound 406 of the tissue site 402.

[0107] FIG. 7B shows a wound sensor 504 disposed between the manifold 206 and the first film layer 204. The wound sensor 504 may be disposed between a plurality of standoffs 240, and at least a portion of the wound sensor 504 may be proximate to one of the plurality of windows 238 of the manifold 206. When the dressing 110 is disposed on the tissue site 402, the wound sensor 504 can be in fluid communication with the wound 406 of the tissue site 402 through at least one or more fluid passageways 228 of the first film layer 204.

[0108] FIG. 7C shows a wound sensor 504 disposed within one of the plurality of windows 238 of the manifold 206. When the dressing 110 is disposed on the tissue site 402, the wound sensor 504 can be in fluid communication with the wound 406 of the tissue site 402 through at least one or more fluid passageways 228 of the first film layer 204.

[0109] FIG. 7D shows a wound sensor 504 disposed between the manifold 206 and the second film layer 208. A portion of the manifold 206 may be embedded between a plurality of standoffs 240 of the manifold 206 such that the first surface 702 of the wound sensor 504 is coplanar with the first surface 232 of the manifold 206. When the dressing 110 is disposed on the tissue site 402, the wound sensor 504 can be in fluid contact with the wound 406 of the tissue site 402 through one or more fluid passageways 228 of the manifold 206 and the first film layer 204.

[0110] FIG. 7E shows a wound sensor 504 disposed between a manifold 206 and a second film layer 208. A portion of the manifold 206 may be embedded between a plurality of standoffs 240 of the manifold 206 such that a first surface 702 of the wound sensor 504 is coplanar with a first surface 232 of the manifold 206. The dressing material 110 may further include a sealing material 704 disposed around the wound sensor 504 to fluidly isolate the wound sensor 504 from the wound 406. In some embodiments, the wound sensor 504 can have an edge 706 that can couple the first surface 702 of the wound sensor 504 to a second surface 710 of the wound sensor 504. The edge 706 and the second surface 710 of the wound sensor 504 can be coupled to the sealing material. The first surface 702 of the wound sensor 504 can be coupled to the second film layer 208 to fluidly isolate the wound sensor 504 from both the surrounding environment and the wound 406.

[0111] FIG. 7F shows a wound sensor 504 coupled to a first surface 250 of a second film layer 208 on an opposite side of one of a plurality of windows 238 of the manifold 206. A portion 712 of the second film layer 208 can be disposed within one of the plurality of windows 238 of the manifold 206 such that a first surface 702 of the wound sensor 504 is coplanar with a first surface 250 of the second film layer 208. In some embodiments, the wound sensor 504 is isolated from the wound 406 of the tissue site 402 and can provide a baseline or ambient oxygen level reading when the wound sensor 504 is acted upon by a light source. In some embodiments, a plurality of wound sensors 504 can be used such that parameters can be measured at a plurality of locations using the wound sensors 504.

[0112] Figures 8A and 8B show a portion of an alternative embodiment of a dressing material 110 that can be used for deep wounds. In some cases, the wound may have a contour or a deep region that requires a modified dressing material that includes a rolling diaphragm 802. As shown in Figures 8A and 8B, the rolling diaphragm 802 can include a first film layer 204 and a manifold 206. In other embodiments, the rolling diaphragm 802 can further include a second film layer 208. The wound sensor 504 can be disposed on a first surface 232 of the manifold and can be in fluid communication with the wound 406 of the tissue site 402 through one or more fluid passages 228 of the manifold 206 and the first film layer 204. As shown in Figure 8B, in some embodiments, the rolling diaphragm 802 may extend beyond a second surface 224 of the first film layer 204. The rolling diaphragm 802 can enable the dressing material 110 to extend into the deep wound such that the wound sensor 504 can be in closer contact with the deep region of the wound. In some embodiments, the dressing material 110 can be manufactured such that the rolling diaphragms 802 are spaced along the dressing material 110 so that the wound sensor 504 can be disposed at different depths within the wound being treated by the dressing material 110.

[0113] FIG. 9 shows an example of a sensor 900 that can be used with any of the foregoing embodiments of the dressing material 110. In some cases, it may be desirable to monitor multiple parameters at a tissue site using a single sensor. In some embodiments, the sensor 900 may include a fluid sensor 902, an oxygen sensor 904, and a pH sensor 906. In other embodiments, the sensor 900 may monitor fewer or additional parameters. In some embodiments, there may be a liquid barrier 908 that can be disposed around the oxygen sensor 904 and the pH sensor 906 of the sensor 900. The liquid barrier 908 prevents any liquid from the wound from coming into direct contact with the oxygen sensor 904 and the pH sensor 906, but can allow the liquid to come into direct contact with the fluid sensor 902. In some embodiments, the oxygen sensor 904 and the pH sensor 906 can be configured to change color to indicate the oxygen level and the pH level, respectively, when actuated by a light source. In some embodiments, the intensity of the emitted light can depend on the value of the sensed parameter, as described above with reference to FIG. 2. The fluid sensor 902 can be configured to detect the presence of a fluid. The fluid sensor 902 may be partially or completely opaque when dry and transparent when exposed to a fluid, such that when the sensor 220 transitions from opaque to transparent, it appears that the sensor 220 is detecting the presence of a fluid. The sensor 900 can be configured in either the periwound region or the wound contact region of the dressing material. In some embodiments, the sensor 900 can be disposed across both the periwound region and the wound contact region, such that the fluid sensor 902 can detect the maceration or presence of fluid within the periwound region where the oxygen sensor 904 and the pH sensor 906 are configured to detect the levels of oxygen and pH in the wound of the tissue site.

[0114] FIG. 10 shows an exemplary embodiment of a therapy system 100 deployed at a tissue site 402, where a light source 1002 is illuminating a dressing 110. The light source 1002 can emit light 1004 toward the dressing 110. The light 1004 can pass through a cover 125 of the dressing 110 and reach a periwound sensor 502 and a wound sensor 504 around the wound site. When the light 1004 reaches the periwound sensor 502 and the wound sensor 504, the periwound sensor 502 and the wound sensor 504 can change color. The colors of the periwound sensor 502 and the wound sensor 504 correspond to the values of the sensed parameters at the locations where they are disposed. For example, if the sensed parameter is an oxygen level, the periwound sensor 502 and the wound sensor 504 may change color corresponding to the oxygen levels they each sense. The periwound sensor 502 may be a first color 1006 indicating a first oxygen level, and the wound sensor 504 may be a second color 1008 indicating a second oxygen level. The second color 1008 from the wound sensor 504 may be stronger or brighter than the first color 1006, which can indicate that the wound sensor 504 is sensing a lower oxygen level than the periwound sensor 502.

[0115] In some embodiments, although not shown herein, a UV sensing CCD camera can be disposed above the dressing 110 on the opposite side of the tissue site 402 to capture the intensity of the light emitted from the periwound sensor 502 and the wound sensor 504. In some embodiments, although not shown herein, the light source 1002 may include an excitation filter that can condense and filter out light of a specific wavelength so that only light of a specific wavelength reaches the periwound sensor 502 and the wound sensor 504 of the dressing 110. Similarly, in some embodiments, the UV sensing CCD camera may include an emission filter to filter and condense the light emitted by the periwound sensor 502 and the wound sensor 504.

[0116] Methods for treating tissue site 402 by negative pressure are also described herein. The method can include placing dressing 110 over tissue site 402, applying negative pressure from negative pressure source 105 to dressing 110, and monitoring dressing 110 for changes in sensed parameters at tissue site 402. Dressing 110 can include cover 125, wound contact layer 202, manifold 206, and at least one sensor such as sensor 220, periwound sensor 502, or wound sensor 504. Cover 125 can include a first surface 262 and a second surface 264. Wound contact layer 202 can include a first surface 210 and a second surface 212. The second surface 212 of wound contact layer 202 can be configured to contact tissue site 402. Manifold 206 can include a first surface 232 and a second surface 234. Manifold 206 can be configured to be disposed between the second surface 264 of cover 125 and the first surface 210 of wound contact layer 202. The at least one sensor can include a plurality of parameter sensing molecules dissolved in a polymer matrix. The at least one sensor can be configured to indicate a sensed parameter when the at least one sensor is actuated by light source 1002.

[0117] In some exemplary embodiments, monitoring the dressing for changes in sensed parameters at tissue site 402 can include detecting a change in color in the at least one sensor when the at least one sensor is actuated by a light source. In some exemplary embodiments, the sensed parameter can include at least one of fluid level, oxygen level, and pH.

[0118] The systems, devices, and methods described herein can provide significant advantages. For example, the dressing material 110 may be transparent, thereby enabling a clinician to easily monitor the tissue site 402 without obstructing the dressing material 110. Sensors such as the sensor 220, the periwound sensor 502, and the wound sensor 504 can all assist a clinician in monitoring the tissue site 402 for changes in parameters such as oxygen level, pH level, and fluid detection. These sensors can transmit more information about the tissue site 402 without requiring any electrical components integrated into the dressing material 110, thereby making the dressing material smarter.

[0119] Although several exemplary embodiments have been shown, those skilled in the art will recognize that the systems, devices, and methods described herein are capable of various changes and modifications within the scope of the appended claims. Further, descriptions of various alternative cases 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 object to a single instance unless clearly required by the context. Components can also be combined or excluded in various configurations for the purposes of sale, manufacture, assembly, or use. For example, in some configurations, the dressing material 110, the container 115, or both can be excluded or separated from the components for manufacture or sale. In other exemplary configurations, the controller 130 can also be manufactured, configured, assembled, or sold independently of the other components.

[0120] The appended claims recite novel and inventive aspects of the above subject matter, but the claims may also encompass additional subject matter that is not specifically recited in detail. For example, certain features, elements, or aspects may be omitted from the claims if they are not necessary to distinguish novel and inventive features from those already known to a person of 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 that serve the same, equivalent, or similar purpose without departing from the scope of the invention as defined by the appended claims.

Claims

1. A dressing material for treating tissue sites with negative pressure, A cover comprising a first surface and a second surface, A wound contact layer comprising a first surface, a second surface, and a central opening, wherein the second surface of the wound contact layer is configured to contact the area surrounding the wound of the tissue site, A first film layer comprising a first surface and a second surface, wherein the second surface of the first film layer is configured to contact the wound in the tissue area, A manifold comprising a first surface and a second surface, wherein the manifold is configured to be positioned between the second surface of the cover and the first surface of the first film layer, Equipped with, The wound contact layer further comprises at least one sensor comprising a plurality of oxygen-sensing molecules dissolved in a polymer matrix, wherein the at least one sensor is configured to change color to indicate the sensed oxygen level when acted upon by a light source. Dressing ingredients.

2. The dressing material according to claim 1, wherein the wound contact layer further comprises a peripheral portion surrounding the central opening, and the peripheral portion comprises a plurality of openings.

3. The dressing material according to claim 2, wherein the at least one sensor is located in one of the plurality of openings in the wound contact layer.

4. The dressing material according to claim 2, wherein the at least one sensor is positioned between the first surface of the wound contact layer and the second surface of the cover, and the at least one sensor is adjacent to at least one of the plurality of openings in the wound contact layer.

5. The dressing material according to claim 2, wherein the at least one sensor is positioned between the first surface of the wound contact layer and the second surface of the cover, and the at least one sensor is offset from the plurality of openings in the wound contact layer.

6. The dressing material according to claim 1, wherein the at least one sensor includes an oxygen-sensing film.

7. The dressing material according to claim 6, wherein the oxygen sensing film comprises a low oxygen permeable polymer or a high oxygen permeable polymer, the low oxygen permeable polymer comprises one of polyvinyl alcohol, ethylene vinyl alcohol, polyacrylonitrile, and polyvinylidene chloride, and the high oxygen permeable polymer comprises one of silicone and polyolefin elastomer.

8. The dressing material according to claim 1, wherein the at least one sensor includes a multisensor configured to detect a fluid level, an oxygen level, and a pH level.

9. A dressing material for treating tissue sites with negative pressure, A cover comprising a first surface and a second surface, A wound contact layer comprising a first surface, a second surface, a peripheral portion having a plurality of openings, and a central opening, wherein the second surface of the wound contact layer is configured to contact the wound-periphery region of the tissue site, A first film layer comprising a first surface and a second surface, wherein the second surface of the first film layer is configured to contact the wound in the tissue area, A manifold comprising a first surface and a second surface, wherein the manifold is configured to be positioned between the second surface of the cover and the first surface of the first film layer, Equipped with, The cover further comprises at least one sensor comprising a plurality of oxygen-sensing molecules dissolved in a polymer matrix, wherein the at least one sensor is configured to change color to indicate the sensed oxygen level when acted upon by a light source. Dressing ingredients.

10. The dressing material according to claim 9, wherein the at least one sensor is disposed in a recess of the first surface of the cover such that the at least one sensor is aligned with one of the plurality of openings in the wound contact layer.

11. The dressing material according to claim 10, further comprising a recessed cover detachably coupled to the first surface of the cover, wherein the recessed cover is configured to seal the at least one sensor within the recess of the first surface of the cover.

12. The dressing material according to claim 9, wherein the at least one sensor is positioned on the first surface of the cover such that the sensor is aligned with one of the plurality of openings in the wound contact layer.

13. The dressing material according to claim 9, wherein the cover further comprises a central portion having a central opening and a peripheral portion, and the peripheral portion of the cover is configured to bond to the peripheral portion of the wound contact layer.

14. The dressing material according to claim 13, wherein the cover further comprises a second film layer having a first surface and a second surface, the second film layer being configured to substantially descend with the central opening of the cover, and the second surface of the second film layer being bonded to the first surface of the manifold.

15. The dressing material according to claim 14, wherein the at least one sensor is disposed in a recess of the first surface of the second film layer.

16. The dressing material according to claim 15, further comprising a recessed cover removably bonded to the first surface of the second film layer, wherein the recessed cover is configured to seal the at least one sensor within the recess of the first surface of the second film layer.

17. The dressing material according to claim 14, wherein the at least one sensor is disposed between the first surface of the manifold and the second surface of the second film layer.

18. The dressing material according to claim 14, further comprising at least one sealed cavity between the first surface of the manifold and the second surface of the second film layer, wherein the at least one sensor is disposed within the at least one sealed cavity.

19. A dressing material for treating tissue sites with negative pressure, A cover comprising a first surface and a second surface, A wound contact layer comprising a first surface, a second surface, a peripheral portion having a plurality of openings, and a central opening, wherein the second surface of the wound contact layer is configured to contact the wound-periphery region of the tissue site, A first film layer comprising a first surface and a second surface, wherein the second surface of the first film layer is configured to contact the wound in the tissue area, A manifold comprising a first surface and a second surface, wherein the manifold is configured to be positioned between the second surface of the cover and the first surface of the first film layer, The present invention provides an at least one sensor embedded in the second surface of the first film layer, comprising a plurality of oxygen-sensing molecules dissolved in a polymer matrix, and configured to change color to indicate a sensed oxygen level when the at least one sensor is acted upon by a light source, A dressing that includes [the following features].

20. A dressing material for treating tissue sites with negative pressure, A cover comprising a first surface and a second surface, A wound contact layer comprising a first surface, a second surface, a peripheral portion having a plurality of openings, and a central opening, wherein the second surface of the wound contact layer is configured to contact the wound-periphery region of the tissue site, A first film layer comprising a first surface and a second surface, wherein the second surface of the first film layer is configured to contact the wound in the tissue area, A manifold comprising a first surface and a second surface, wherein the manifold is configured to be positioned between the second surface of the cover and the first surface of the first film layer, At least one sensor disposed between the second surface of the manifold and the first surface of the first film layer, comprising a plurality of oxygen-sensing molecules dissolved in a polymer matrix, and configured to change color to indicate a sensed oxygen level when the at least one sensor is acted upon by a light source, A dressing that includes [the following features].

21. The dressing material according to claim 20, wherein the at least one sensor is positioned close to the window of the manifold such that the at least one sensor is visible through the window of the manifold.

22. A wound contact layer for treating a tissue site, The central part and, The peripheral portion surrounding the central portion, having a plurality of openings, A sensor comprising a plurality of oxygen-sensing molecules dissolved in a polymer matrix, wherein the sensor is integrated into the peripheral portion away from each of the plurality of openings and is configured to change color to indicate the sensed oxygen level in response to a light source, A wound contact layer comprising the above.

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