Dressing for negative pressure therapy

Abstract

A dressing for treating a tissue site with negative pressure includes a manifold. The manifold includes: a first major surface; a second major surface opposite to the first major surface with respect to a thickness of the manifold and configured to face the tissue site; a plurality of projections disposed at the first major surface and spaced apart from each other, the plurality of projections at least partly forming the first major surface and defining a plurality of fluid channels therebetween; and a plurality of perforations extending through the manifold, each perforation extending at least partly through a corresponding projection. The dressing further includes a drape disposed adjacent to and coupled to the first major surface. The drape includes a drape aperture extending therethrough. The drape aperture is configured to be coupled to a dressing interface that is in fluid communication with a negative pressure source.

Description

[0001] DRESSING FOR NEGATIVE PRESSURE THERAPY

[0002] Cross-Reference to Related Applications

[0003] This application claims the benefit of priority to U.S. Provisional Application No. 63 / 556,048, filed on February 21, 2024, which is incorporated herein by reference in its entirety.

[0004] Technical Field

[0005] The present disclosure relates generally to a dressing for treating a tissue site with negative pressure and a system including the dressing for providing negative pressure therapy.

[0006] Background

[0007] Clinical studies and practice have shown that reducing pressure in proximity to a tissue site can augment and accelerate growth of new tissue at the tissue site. Treating the tissue site with reduced pressure may be commonly referred to as “negative pressure wound therapy,” but is also known by other names, including “negative pressure therapy,” “reduced-pressure therapy,” “vacuum therapy,” “vacuum-assisted closure,” and “topical negative-pressure,” for example.

[0008] Peel-and-place negative pressure dressings may provide usability benefits over typical customizable negative pressure dressings. However, conventional peel-and-place negative pressure dressings may be expensive to manufacture and / or assemble due to multiple different components that together form the dressing. Consequently, conventional peel-and-place negative pressure dressings may have a high cost of goods (COG) associated thereto. There is a need for a negative pressure dressing that has improved usability, increased wear time, and decreased manufacturing and / or assembly costs.

[0009] Summary

[0010] In a first aspect, the present disclosure provides a dressing for treating a tissue site with negative pressure. The dressing includes a manifold defining a plane, a longitudinal axis disposed in the plane and extending along a length of the manifold, a transverse axis disposed in the plane and extending perpendicular to the longitudinal axis, and a thickness normal to the plane. The manifold includes a first major surface. The manifold further includes a second major surface opposite to the first major surface and spaced apart from the first major surface with respect to the thickness of the manifold. The second major surface is configured to face the tissue site. The manifold further includes a plurality of projections disposed at the first major surface and spaced apart from each other. The plurality of projections defines a plurality of fluid channels therebetween. The plurality of projections at least partly forms the first major surface. Each fluid channel from the plurality of fluid channels extends along the plane of the manifold and defines a width along the plane of the manifold and a height normal to the plane. Each fluid channel further extends partly from the first major surface towards the second major surface, such that the height of each fluid channel is less than the thickness of the manifold. The manifold further includes a plurality of perforations extending through the manifold from the first major surface to the second major surface. Each perforation from the plurality of perforations extends at least partly through a corresponding projection from the plurality of projections. The dressing further includes a drape disposed adjacent to and coupled to the first major surface. The drape covers the first major surface. The drape includes a drape aperture extending therethrough and configured to be coupled to a dressing interface that is in fluid communication with a negative pressure source.

[0011] In a second aspect, the present disclosure provides a system for providing negative pressure therapy. The system includes the dressing of the first aspect. The system further includes a dressing interface coupled to the drape and disposed in fluid communication with the drape aperture. The system further includes a fluid conductor coupled to and disposed in fluid communication with the dressing interface. The system further includes a negative pressure source fluidly coupled to the fluid conductor.

[0012] In a third aspect, the present disclosure provides a dressing for treating a tissue site with negative pressure. The dressing includes a manifold. The manifold includes a first major surface. The manifold further includes a second major surface opposite to the first major surface and spaced apart from the first major surface. The second major surface is configured to face the tissue site. The manifold further includes a plurality of perforations extending through the manifold from the first major surface to the second major surface. The dressing further includes a drape disposed adjacent to and coupled to the first major surface. The drape covers the first major surface. The drape includes a plurality of projections extending from the first major surface of the manifold and a plurality of recesses alternating with the plurality of projections. The drape further includes a plurality of fluid channels. Each fluid channel from the plurality of fluid channels is defined by a corresponding projection from the plurality of projections. Each fluid channel is in fluid communication with at least some of the plurality of perforations of the manifold. The drape further includes a drape aperture extending therethrough and configured to be coupled to a dressing interface that is in fluid communication with a negative pressure source.

[0013] In a fourth aspect, the present disclosure provides a system for providing negative pressure therapy. The system includes the dressing of third aspect. The system further includes a dressing interface coupled to the drape and disposed in fluid communication with the drape aperture. The system further includes a fluid conductor coupled to and disposed in fluid communication with the dressing interface. The system further includes a negative pressure source fluidly coupled to the fluid conductor.

[0014] The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

[0015] Brief Description of Drawings

[0016] Exemplary embodiments disclosed herein are more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labelled with the same number.

[0017] FIG. 1 is a functional block diagram of a system for providing negative pressure therapy according to an embodiment of the present disclosure;

[0018] FIG. 2 is a schematic exploded perspective view of a dressing for treating a tissue site with negative pressure according to an embodiment of the present disclosure;

[0019] FIG. 3 is a schematic top view of a manifold of the dressing of FIG. 2 according to an embodiment of the present disclosure;

[0020] FIG. 4A is a schematic perspective cross-sectional view of a portion of the manifold taken along a line 1-1 of FIG. 3 according to an embodiment of the present disclosure;

[0021] FIG. 4B is a schematic cross-sectional view of a portion of the manifold taken along the line 1- 1 of FIG. 3 according to an embodiment of the present disclosure;

[0022] FIG. 5 is a schematic bottom perspective view of the manifold of FIG. 3 according to an embodiment of the present disclosure;

[0023] FIG. 6 is a schematic exploded perspective view of a dressing according to another embodiment of the present disclosure;

[0024] FIG. 7 is a schematic exploded perspective view of a dressing according to another embodiment of the present disclosure; and

[0025] FIG. 8 is a schematic side cross-sectional view of a portion of a dressing according to another embodiment of the present disclosure.

[0026] Detailed Description

[0027] In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0028] In the following disclosure, the following definitions are adopted.

[0029] As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0030] As used herein as a modifier to a property or attribute, the term “generally,” unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring absolute precision or a perfect match (e.g., within + / - 20 % for quantifiable properties).

[0031] The term “substantially,” unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 10% for quantifiable properties) but again without requiring absolute precision or a perfect match. As used herein, all numbers should be considered modified by the term “about.” The term “about,” unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 5% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0032] As used herein, the terms “first” and “second” are used as identifiers. Therefore, such terms should not be construed as limiting of this disclosure. The terms “first” and “second” when used in conjunction with a feature or an element can be interchanged throughout the embodiments of this disclosure.

[0033] As used herein, when a first material is termed as “similar” to a second material, at least 90 weight % of the first and second materials are identical and any variation between the first and second materials comprises less than about 10 weight % of each of the first and second materials.

[0034] As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B.”

[0035] As used herein, the term “tissue site” 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, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, or ligaments. A wound may include chronic, acute, traumatic, subacute, and dehisced wounds, partial-thickness bums, ulcers (such as diabetic, pressure, or venous insufficiency ulcers), flaps, and grafts, for example. The term “tissue site” may also refer to areas of any tissue that are not necessarily wounded or defective, but are instead areas in which it may be desirable to add or promote growth of additional tissue.

[0036] As used herein, the term “between about,” unless otherwise specifically defined, generally refers to an inclusive or a closed range. For example, if a parameter X is between about A and B, then A < X < B.

[0037] Dressings described herein may be useful for use in negative pressure wound therapy (NPWT) for treating a tissue site. The dressings may include three or less functional layers. The dressings may have extended wear time, for example, greater than 3 days, greater than 5 days, or greater than 7 days. Further, the dressings may improve wound healing over current standard of care (SOC).

[0038] The present disclosure relates to a dressing for treating a tissue site with negative pressure. The dressing includes a manifold defining a plane, a longitudinal axis disposed in the plane and extending along a length of the manifold, a transverse axis disposed in the plane and extending perpendicular to the longitudinal axis, and a thickness normal to the plane. The manifold includes a first major surface. The manifold further includes a second major surface opposite to the first major surface and spaced apart from the first major surface with respect to the thickness of the manifold. The second major surface is configured to face the tissue site. The manifold further includes a plurality of projections disposed at the first major surface and spaced apart from each other. The plurality of projections defines a plurality of fluid channels therebetween. The plurality of projections at least partly forms the first major surface. Each fluid channel from the plurality of fluid channels extends along the plane of the manifold and defines a width along the plane of the manifold and a height normal to the plane. Each fluid channel further extends partly from the first major surface towards the second major surface, such that the height of each fluid channel is less than the thickness of the manifold. The manifold further includes a plurality of perforations extending through the manifold from the first major surface to the second major surface. Each perforation from the plurality of perforations extends at least partly through a corresponding projection from the plurality of projections. The dressing further includes a drape disposed adjacent to and coupled to the first major surface. The drape covers the first major surface. The drape includes a drape aperture extending therethrough and configured to be coupled to a dressing interface that is in fluid communication with a negative pressure source.

[0039] The dressing of the present disclosure may transmit negative pressure from the negative pressure source to the tissue site while managing fluids (i.e., wound exudate) from the tissue site. Specifically, upon placement of the dressing on the tissue site, the plurality of perforations of the manifold may distribute negative pressure from the negative pressure source to the tissue site. As a result, the fluids from the tissue site may move through the plurality of perforations to the plurality of fluid channels of the manifold. The plurality of fluid channels may manage the fluids and facilitate removal of the fluids through the dressing interface. The plurality of fluid channels and the plurality of perforations may together ensure optimal fluid management during use of the dressing. Moreover, the plurality of fluid channels may prevent the drape from collapsing thereinto, thereby ensuring that the dressing maintains its fluid handling capabilities under negative pressure.

[0040] The plurality of fluid channels and the plurality of perforations may enable the manifold to be formed as a unitary molded component. The plurality of fluid channels and the plurality of perforations may provide the manifold with desirable fluid handling and negative pressure distribution capabilities while having a unitary molded structure. Due to the unitary molded structure of the manifold, the dressing of the present disclosure may be more economical and easier to manufacture and assemble in comparison to conventional negative pressure dressings that have multi-layered manifolds or openfoam manifolds. The manifold of the present disclosure may be made from, for example, a closed-cell foam or silicone.

[0041] The dressing may also increase formation of granulation tissue at the tissue site (i.e., provide faster healing). Specifically, the dressing may augment and accelerate growth of new tissue at the tissue site. The dressing may also be suitable for long-term wear (e.g., greater than 3 days, greater than 5 days, or greater than 7 days). Specifically, the dressing may be used to treat the tissue site for a prolonged time period (e.g., greater than 3 days, greater than 5 days, or greater than 7 days) before needing replacement. The dressing may maintain its fluid handling and manifolding capabilities during the prolonged time period. The dressing may also reduce tissue-ingrowth over the prolonged time period with reduced slough and maintained granulation tissue.

[0042] Referring now to the figures, FIG. 1 illustrates a functional block diagram of a system 10 for providing negative pressure therapy (also referred to as “negative pressure wound therapy” or “NPWT”) according to an embodiment of the present disclosure. The system 10 includes a negative pressure source 25. The system 10 may further include one or more distribution components. A distribution component may be detachable and may be disposable, reusable, and / or recyclable. A dressing, such as a dressing 100, and a fluid container, such as a container 15, are examples of distribution components that may be associated with the system 10. Specifically, the system 10 includes the dressing 100. As shown in FIG. 1, the dressing 100 may include a tissue interface 160, a cover or drape 102, or both in some embodiments.

[0043] A fluid conductor is another example of a distribution component. A “fluid conductor,” in this context, broadly includes a tube, pipe, hose, conduit, or other structure with one or more lumina or open pathways adapted to convey a fluid between two ends. Typically, a tube is an elongated, cylindrical structure with some flexibility, but the geometry and rigidity may vary. Moreover, some fluid conductors may be molded into or otherwise integrally combined with other components. Distribution components may also include interfaces or fluid ports to facilitate coupling and de-coupling other components. In some embodiments, for example, a dressing interface may facilitate coupling a fluid conductor to the dressing 100. For example, such a dressing interface may be a SENSAT.R.A.C.™ Pad available from Kinetic Concepts, Inc. of San Antonio, Tex.

[0044] The system 10 may further include a regulator or controller, such as a controller 30. Additionally, the system 10 may include sensors to measure operating parameters and provide feedback signals to the controller 30 indicative of the operating parameters. As shown in FIG. 1, for example, the system 10 may include a first sensor 35 and a second sensor 40, and each of the first sensor 35 and the second sensor 40 may be communicably coupled to the controller 30.

[0045] In some embodiments, the system 10 may further include a source of instillation solution. For example, a solution source 45 may be fluidly coupled to the dressing 100, as shown in FIG. 1. The solution source 45 may be fluidly coupled to a positive pressure source, such as a positive-pressure source 50, a negative pressure source, such as the negative pressure source 25, or both in some embodiments. A regulator, such as an instillation regulator 55, may also be fluidly coupled to the solution source 45 and the dressing 100 to ensure proper dosage of instillation solution (e.g., saline) to a tissue site. For example, the instillation regulator 55 may include a piston that can be pneumatically actuated by the negative pressure source 25 to draw instillation solution from the solution source during a negative pressure interval and to instill the solution to a dressing during a venting interval. Additionally, or alternatively, the controller 30 may be coupled to the negative pressure source 25, the positive-pressure source 50, or both, to control dosage of instillation solution to a tissue site. In some embodiments, the instillation regulator 55 may also be fluidly coupled to the negative pressure source 25 through the dressing 100, as shown in FIG. 1.

[0046] Some components of the system 10 may be housed within or used in conjunction with other components, such as sensors, processing units, alarm indicators, memory, databases, software, display devices, or user interfaces that further facilitate therapy. For example, in some embodiments, the negative pressure source 25 may be combined with the controller 30, the solution source 45, and other components into a therapy unit.

[0047] In general, components of the system 10 may be coupled directly or indirectly. For example, the negative pressure source 25 may be directly coupled to the container 15 and may be indirectly coupled to the dressing 100 through the container 15. Coupling may include fluid, mechanical, thermal, electrical (wired or wireless), or chemical coupling (such as a chemical bond), or some combination of coupling in some contexts. For example, the negative pressure source 25 may be electrically coupled to the controller 30 and may be fluidly coupled to one or more distribution components to provide a fluid path to a tissue site. In some embodiments, components may also be coupled by virtue of physical proximity, being integral to a single structure, or being formed from the same piece of material.

[0048] A negative pressure supply, such as the negative pressure source 25, may be a reservoir of air at a negative pressure or may be a manual or electrically powered device, such as a vacuum pump, a suction pump, a wall suction port available at many healthcare facilities, or a micro-pump, for example. “Negative pressure” generally refers to a pressure less than a local ambient pressure, such as the ambient pressure in a local environment external to a sealed therapeutic environment. In many cases, the local ambient pressure may also be the atmospheric pressure at which a tissue site is located. Alternatively, the pressure may be less than a hydrostatic pressure associated with tissue at the tissue site. Unless otherwise indicated, values of pressure stated herein are gauge pressures. References to increases in negative pressure typically refer to a decrease in absolute pressure, while decreases in negative pressure typically refer to an increase in absolute pressure. While the amount and nature of negative pressure provided by the negative pressure source 25 may vary according to therapeutic requirements, the pressure is generally a low vacuum, also commonly referred to as a rough vacuum, between -5 mm Hg (-667 Pa) and -500 mm Hg (-66.7 kPa). Common therapeutic ranges are between -50 mm Hg (-6.7 kPa) and -300 mm Hg (-39.9 kPa).

[0049] The container 15 is representative of a container, canister, pouch, absorbent, or other storage component, which can be used to manage exudates and other fluids withdrawn from a tissue site. In many environments, a rigid container may be preferred or required for collecting, storing, and disposing of fluids. In other environments, fluids may be properly disposed of without rigid container storage, and a re-usable container could reduce waste and costs associated with negative pressure therapy.

[0050] A controller, such as the controller 30, may be a microprocessor or computer programmed to operate one or more components of the system 10, such as the negative pressure source 25. In some embodiments, for example, the controller 30 may be a microcontroller, which generally includes an integrated circuit containing a processor core and a memory programmed to directly or indirectly control one or more operating parameters of the system 10. Operating parameters may include the power applied to the negative pressure source 25, the pressure generated by the negative pressure source 25, or the pressure distributed to the tissue interface 160, for example. The controller 30 is also preferably configured to receive one or more input signals, such as a feedback signal, and programmed to modify one or more operating parameters based on the input signals.

[0051] Sensors, such as the first sensor 35 and the second sensor 40, are generally known in the art as any apparatus operable to detect or measure a physical phenomenon or property, and generally provide a signal indicative of the phenomenon or property that is detected or measured. For example, the first sensor 35 and the second sensor 40 may be configured to measure one or more operating parameters of the system 10. In some embodiments, the first sensor 35 may be a transducer configured to measure pressure in a pneumatic pathway and convert the measurement to a signal indicative of the pressure measured. In some embodiments, for example, the first sensor 35 may be a piezo -resistive strain gauge. The second sensor 40 may optionally measure operating parameters of the negative pressure source 25, such as a voltage or current, in some embodiments. Preferably, the signals from the first sensor 35 and the second sensor 40 are suitable as an input signal to the controller 30, but some signal conditioning may be appropriate in some embodiments. For example, the signal may need to be filtered or amplified before it can be processed by the controller 30. Typically, the signal is an electrical signal, but may be represented in other forms, such as an optical signal.

[0052] As noted above, the dressing 100 may include the tissue interface 160, the drape 102, or both in some embodiments. The tissue interface 160 can be generally adapted to partially or fully contact a tissue site. The tissue interface 160 may take many forms, and may have many sizes, shapes, or thicknesses, depending on a variety of factors, such as the type of treatment being implemented or the nature and size of a tissue site. For example, the size and shape of the tissue interface 160 may be adapted to the contours of deep and irregular shaped tissue sites.

[0053] The tissue interface 160 may include one or more manifolds. A manifold in this context may include a means for collecting or distributing fluid across the tissue interface 160 under pressure. For example, a manifold may be adapted to receive negative pressure from a source and distribute negative pressure through multiple apertures across the tissue interface 160, which may have the effect of collecting fluid from across a tissue site and drawing the fluid toward the source. In some embodiments, the fluid path may be reversed, or a secondary fluid path may be provided to facilitate delivering fluid, such as fluid from a source of instillation solution, across a tissue site.

[0054] In addition to the tissue interface 160, the dressing 100 may further include the drape 102. In some embodiments, the drape 102 may provide a bacterial barrier and protection from physical trauma. The drape 102 may also be constructed from a material that can reduce evaporative losses and provide a fluid seal between two components or two environments, such as between a therapeutic environment and a local external environment. The drape 102 may include, for example, an elastomeric film or membrane that can provide a seal adequate to maintain a negative pressure at a tissue site for a given negative pressure source. The drape 102 may have a high moisture-vapor transmission rate (MVTR) in some applications. For example, the MVTR may be at least 250 grams per square meter per twenty- four hours in some embodiments, measured using an upright cup technique according to ASTM E96 / E96M Upright Cup Method at 38° C. and 10% relative humidity (RH). In some embodiments, an MVTR up to 5,000 grams per square meter per twenty-four hours may provide effective breathability and mechanical properties.

[0055] In some example embodiments, the drape 102 may be a non-porous polymer drape or film, such as a polyurethane film, that is permeable to water vapor but impermeable to liquid. Such drapes typically have a thickness in the range of 25-50 microns. For permeable materials, the permeability generally should be low enough that a desired negative pressure may be maintained. The drape 102 may include, for example, one or more of the following materials: polyurethane (PU), such as hydrophilic polyurethane; cellulosics; hydrophilic polyamides; polyvinyl alcohol; polyvinyl pyrrolidone; hydrophilic acrylics; silicones, such as hydrophilic silicone elastomers; natural rubbers; polyisoprene; styrene butadiene rubber; chloroprene rubber; polybutadiene; nitrile rubber; butyl rubber; ethylene propylene rubber; ethylene propylene diene monomer; chlorosulfonated polyethylene; polysulfide rubber; ethylene vinyl acetate (EVA); co-polyester; and polyether block polymide copolymers. Such materials are commercially available as, for example, Tegaderm® drape, commercially available from 3M Company, Minneapolis Minn.; polyurethane (PU) drape, commercially available from Avery Dennison Corporation, Pasadena, Calif.; poly ether block polyamide copolymer (PEBAX), for example, from Arkema S. A., Colombes, France; and Inspire 2301 and Inpsire 2327 polyurethane films, commercially available from Coveris Advanced Coatings, Wrexham, United Kingdom. In some embodiments, the drape 102 may include INSPIRE 2301 having an MVTR (upright cup technique) of 2600 g / m2 / 24 hours and a thickness of about 30 microns.

[0056] An attachment device may be used to attach the drape 102 to an attachment surface, such as undamaged epidermis, a gasket, or another cover. The attachment device may take many forms. For example, an attachment device may be a medically acceptable, pressure-sensitive adhesive configured to bond the drape 102 to epidermis around a tissue site. In some embodiments, for example, some or all of the drape 102 may be coated with an adhesive, such as an acrylic adhesive, which may have a coating weight of about 25-65 grams per square meter (g.s.m.). Thicker adhesives, or combinations of adhesives, may be applied in some embodiments to improve the seal and reduce leaks. Other example embodiments of an attachment device may include a double-sided tape, paste, hydrocolloid, hydrogel, silicone gel, or organogel.

[0057] The solution source 45 may also be representative of a container, canister, pouch, bag, or other storage component, which can provide a solution for instillation therapy. Compositions of solutions may vary according to a prescribed therapy, but examples of solutions that may be suitable for some prescriptions include hypochlorite-based solutions, silver nitrate (0.5%), sulfur-based solutions, biguanides, cationic solutions, and isotonic solutions.

[0058] The dressings disclosed herein may be used with negative pressure therapy. In some embodiments, the dressing 100 disclosed herein may be used for at least 5, 6, 7, 8, 9, 10, 11, or 12 days to promote granulation and / or minimize tissue in-growth with a source of negative pressure. For example, the dressing 100 disclosed herein may remain on a tissue site, such as a surface wound, for at least 5 to 7 days.

[0059] In operation, the tissue interface 160 may be placed within, over, on, or otherwise proximal to a tissue site. If the tissue site is a wound, for example, the tissue interface 160 may partially or completely fill the wound, or it may be placed over the wound. The drape 102 may be placed over the tissue interface 160 and sealed to an attachment surface near a tissue site. For example, the drape 102 may be sealed to undamaged epidermis peripheral to a tissue site. Thus, the dressing 100 can provide a sealed therapeutic environment proximal to a tissue site, substantially isolated from the external environment, and the negative pressure source 25 can reduce pressure in the sealed therapeutic environment.

[0060] The fluid mechanics of using a negative pressure source to reduce pressure in another component or location, such as within a sealed therapeutic environment, can be mathematically complex. However, the basic principles of fluid mechanics applicable to negative pressure therapy and instillation are generally well-known to those skilled in the art, and the process of reducing pressure may be described illustratively herein as “delivering,” “distributing,” or “generating” negative pressure, for example.

[0061] In general, exudate and other fluid flow toward lower pressure along a fluid path. Thus, the term “downstream” typically implies something in a fluid path relatively closer to a source of negative pressure or further away from a source of positive pressure. Conversely, the term “upstream” implies something relatively further away from a source of negative pressure or closer to a source of positive pressure. Similarly, it may be convenient to describe certain features in terms of fluid “inlet” or “outlet” in such a frame of reference. This orientation is generally presumed for purposes of describing various features and components herein. However, the fluid path may also be reversed in some applications, such as by substituting a positive-pressure source for a negative pressure source, and this descriptive convention should not be construed as a limiting convention.

[0062] Negative pressure applied across the tissue site through the tissue interface 160 in the sealed therapeutic environment can induce macro-strain and micro-strain in the tissue site. Negative pressure can also remove exudate and other fluid from a tissue site, which can be collected in the container 15.

[0063] In some embodiments, the controller 30 may receive and process data from one or more sensors, such as the first sensor 35. The controller 30 may also control the operation of one or more components of the system 10 to manage the pressure delivered to the tissue interface 160. In some embodiments, controller 30 may include an input for receiving a desired target pressure and may be programmed for processing data relating to the setting and inputting of the target pressure to be applied to the tissue interface 160. In some example embodiments, the target pressure may be a fixed pressure value set by an operator as the target negative pressure desired for therapy at a tissue site and then provided as input to the controller 30. The target pressure may vary from tissue site to tissue site based on the type of tissue forming a tissue site, the type of injury or wound (if any), the medical condition of the patient, and the preference of the attending physician. After selecting a desired target pressure, the controller 30 can operate the negative pressure source 25 in one or more control modes based on the target pressure and may receive feedback from one or more sensors to maintain the target pressure at the tissue interface 160.

[0064] FIG. 2 illustrates a schematic exploded perspective view of the dressing 100 for treating a tissue site with negative pressure according to an embodiment of the present disclosure.

[0065] The dressing 100 includes a manifold 110. The manifold 110 may be generally adapted to partially or fully contact the tissue site. The manifold 110 may distribute negative pressure to the tissue site and manage fluids (i.e., wound exudate) from the tissue site. In the illustrated embodiment of FIG. 2, the tissue interface 160 of the dressing 100 includes the manifold 110.

[0066] The dressing 100 further includes the drape 102. The drape 102 may be coupled to the manifold 110. In some embodiments, the drape 102 may be bonded to the manifold 110. One example of a fluid conductor 65 and a dressing interface 60 of the system 10 of FIG. 1 is also illustrated in FIG. 2.

[0067] Referring to FIGS. 1 and 2, the system 10 includes the dressing interface 60 and the fluid conductor 65. The drape 102 includes a drape aperture 104 extending therethrough. In other words, the drape aperture 104 is a through-aperture. The drape aperture 104 is configured to be coupled to the dressing interface 60 that is in fluid communication with the negative pressure source 25. That is, the dressing interface 60 is coupled to the drape 102 and disposed in fluid communication with the drape aperture 104. The dressing interface 60 may be placed over the drape aperture 104 to provide fluid communication between the fluid conductor 65 and the tissue interface 160. The fluid conductor 65 is coupled to and disposed in fluid communication with the dressing interface 60. The fluid conductor 65 may be fluidly coupled on one end to the dressing interface 60, and the negative pressure source 25 may be fluidly coupled to the fluid conductor 65. The negative pressure source 25 may apply negative pressure to the tissue site via the fluid conductor 65.

[0068] In the illustrated embodiment of FIG. 2, the dressing 100 further includes a release liner 106. The release liner 106 may be removably attached to the manifold 110. The release liner 106 may further be removably attached to a portion or periphery of the drape 102. In some embodiments, the release liner 106 may be bonded to the drape 102 and in contact with the manifold 110. The release liner 106 may be removed from the dressing 100 before placing the dressing 100 on the tissue site. The release liner 106 may also provide stiffness to the dressing 100, which can facilitate deployment of the dressing 100.

[0069] The release liner 106 may be, for example, a casting paper, a film, or polyethylene. In some embodiments, the release liner 106 may be a polyester material such as polyethylene terephthalate (PET), or similar polar semi-crystalline polymer. Further, the release liner 106 may include a release agent disposed on a side of the release liner 106 that is configured to contact the manifold 110 and / or the drape 102. For example, the release agent may be a silicone coating and may have a release factor suitable to facilitate removal of the release liner 106 by hand and without damaging or deforming the dressing 100. In some embodiments, the release agent may be a fluorocarbon or a fluorosilicone, for example. In other embodiments, the release liner 106 may be uncoated or otherwise used without a release agent.

[0070] The dressing 100 may be placed within, over, on, or otherwise proximal to the tissue site. The dressing 100 may provide a sealed therapeutic environment proximal to the tissue site, substantially isolated from an external environment. In some configurations, the dressing 100 may be left on the tissue site for long-term wear (e.g., greater than 3 days, greater than 5 days, or greater than 7 days) with low risk of tissue in-growth or loss of effectiveness of the manifold 110. The dressing 100 may be particularly advantageous for use with treatment of moderate depth tissue site with medium-to-high levels of exudate. The manifold 110 will now be described in detail with additional reference to FIGS. 3-5.

[0071] FIG. 3 illustrates a schematic top view of the manifold 110 according to an embodiment of the present disclosure. FIG. 4A illustrates a schematic perspective cross-sectional view of a portion of the manifold 110 taken along a line 1-1 of FIG. 3. FIG. 4B illustrates a schematic cross-sectional view of a portion of the manifold 110 taken along the line 1 - 1. FIG. 5 illustrates a schematic bottom perspective view of the manifold 110 according to an embodiment of the present disclosure.

[0072] Referring to FIGS. 2, 3, 4A, 4B, and 5, the manifold 110 defines a plane 112 (schematically depicted by a block in FIGS. 3 and 4A, and by a line in FIG. 4B). The manifold 110 further defines a longitudinal axis 114 disposed in the plane 112 and extending along a length of the manifold 110. The manifold 110 further defines a transverse axis 116 disposed in the plane 112 and extending perpendicular to the longitudinal axis 114. The manifold 110 further defines a thickness HOT normal to the plane 112 of the manifold 110. That is, the thickness 110T is defined perpendicular to the plane 112.

[0073] The manifold 110 includes a first major surface 122 and a second major surface 124 opposite to the first major surface 122. The second major surface 124 is spaced apart from the first major surface 122 with respect to the thickness 110T of the manifold 110. The second major surface 124 is configured to face the tissue site.

[0074] The manifold 110 further includes a plurality of projections 126 disposed at the first major surface 122 and spaced apart from each other. The plurality of projections 126 at least partly forms the first major surface 122. The plurality of projections 126 may extend partly from the first major surface 122 towards the second major surface 124.

[0075] The plurality of projections 126 defines a plurality of fluid channels 130 therebetween. Each fluid channel 130 from the plurality of fluid channels 130 extends along the plane 112 of the manifold 110. Each fluid channel 130 defines a width 130W along the plane 112 of the manifold 110 and a height 13 OH normal to the plane 112. Each fluid channel 130 further extends partly from the first maj or surface 122 towards the second major surface 124, such that the height 130H of each fluid channel 130 is less than the thickness 110T of the manifold 110. The manifold 110 further includes a plurality of perforations 128 extending through the manifold 110 from the first major surface 122 to the second major surface 124. In other words, each of the plurality of perforations 128 may be a through-perforation. Each perforation 128 from the plurality of perforations 128 extends at least partly through a corresponding projection 126 from the plurality of projections 126. In some embodiments, each perforation 128 may be a slit. The slit may have a linear, curved, or otherwise irregular geometry.

[0076] Upon placement of the dressing 100 on the tissue site, at least some of the plurality of perforations 128 may be in fluid communication with the tissue site. The plurality of perforations 128 may distribute negative pressure from the negative pressure source 25 (shown in FIG. 1) to the tissue site. As a result, the fluids from the tissue site may move through the plurality of perforations 128 to the plurality of fluid channels 130. The plurality of fluid channels 130 may manage the fluids and facilitate removal of the fluids through the dressing interface 60. The plurality of fluid channels 130 and the plurality of perforations 128 may together ensure optimal fluid management during use of the dressing 100 over a prolonged period of time (e.g., greater than 3 days, greater than 5 days, or greater than 7 days). This may promote healing of the tissue site more quickly than current standard of care.

[0077] In some embodiments, the plurality of fluid channels 130 includes a collection channel 132. In some embodiments, the plurality of fluid channels 130 further includes a plurality of converging channels 134 spaced apart from each other and converging at the collection channel 132. Each converging channel 134 from the plurality of converging channels 134 is disposed in fluid communication with the collection channel 132. The plurality of converging channels 134 may facilitate movement of fluids from the tissue site to the collection channel 132. The collection channel 132 may thus accumulate fluids from the tissue site and facilitate removal of the fluids through the dressing interface 60. In some embodiments, the drape aperture 104 may be aligned with the collection channel 132. Alignment of the drape aperture 104 with the collection channel 132 may facilitate movement of fluids accumulated in the collection channel 132 to the dressing interface 60, and subsequently to the container 15 of the system 10 (shown in FIG. 1).

[0078] The collection channel 132 may have any suitable shape / geometry based upon desired application attributes. In the illustrated embodiment of FIG. 3, the collection channel 132 is substantially linear. In some embodiments, the collection channel 132 may be curved. The collection channel 132 may have larger dimensions than the rest of the plurality of fluid channels 130. For example, the height 13 OH and the width 130W of the collection channel 132 may be greater than that of each of the rest of the plurality of fluid channels 130.

[0079] Further, each converging channel 134 may have any suitable shape / geometry based upon desired application attributes. In some embodiments, each converging channel 134 may be linear. In some other embodiments, each converging channel 134 may be curved. In some embodiments, each converging channel 134 may have a wavy or otherwise irregular shape. In some embodiments, at least one converging channel 134 from the plurality of converging channels 134 may be inclined obliquely to the longitudinal axis 114. In some embodiments, at least one converging channel 134 from the plurality of converging channels 134 may be parallel to the longitudinal axis 114. In some embodiments, at least one converging channel 134 from the plurality of converging channels 134 may be parallel to the transverse axis 116. In some embodiments, at least one converging channel 134 may be inclined obliquely to the longitudinal axis 114, at least one converging channel 134 may be parallel to the longitudinal axis 114, and at least one converging channel 134 may be parallel to the transverse axis 116. Such an arrangement of the plurality of converging channels 134 may improve movement of fluids from the plurality of converging channels 134 to the collection channel 132.

[0080] In some embodiments, the plurality of fluid channels 130 further includes a plurality of cross channels 136 spaced apart from each other and the collection channel 132. Each cross channel 136 intersects with each converging channel 134, such that the plurality of converging channels 134 and the plurality of cross channels 136 may form a grid. The grid formed by the plurality of cross channels 136 and the plurality of converging channels 134 may improve collection of fluids from the tissue site and movement of fluids to the collection channel 132.

[0081] Each cross channel 136 may have any suitable shape / geometry based upon desired application attributes. In the illustrated embodiment of FIG. 3, each cross channel 136 is oval. In some other embodiments, each cross channel 136 may have a rectangular, pentagonal, hexagonal, or any other suitable polygonal shape.

[0082] In some embodiments, the manifold 110 may further include a plurality of channel walls 138 corresponding to the plurality of fluid channels 130, such that each channel wall 138 forms a corresponding fluid channel 130 from the plurality of fluid channels 130. In some embodiments, at least some of the plurality of perforations 128 may at least partially extend through corresponding channel walls 138 from the plurality of channel walls 138. This may further improve collection of fluids from the tissue site to the plurality of fluid channels 130.

[0083] In some embodiments, the plurality of projections 126 includes a peripheral projection 144 surrounding the rest of the plurality of projections 126. Further, each converging channel 134 extends from the peripheral projection 144 to the collection channel 132. The peripheral projection 144 and one or more adjacent projections 126 from the plurality of projections 126 may define a peripheral cross channel 137 from the plurality of cross channels 136. The peripheral cross channel 137 may surround the rest of the plurality of cross channels 136.

[0084] Referring to FIGS. 2 and 4B, in some embodiments, the manifold 110 further includes a peripheral flange 142 surrounding the plurality of fluid channels 130 and partly forming the first major surface 122. The peripheral flange 142 may extend from the peripheral projection 144 away from the collection channel 132. The peripheral flange 142 may be coupled to the drape 102. Specifically, in some embodiments, the dressing 100 may further include a peripheral adhesive layer 143 (schematically depicted in FIG. 4B) at least partially covering the peripheral flange 142. The peripheral adhesive layer 143 may include an adhesive that adhesively bonds the peripheral flange 142 to the drape 102. The adhesive of the peripheral adhesive layer 143 may include, for example, a medically acceptable, pressure-sensitive adhesive. In some embodiments, the peripheral adhesive layer 143 may be continuous or discontinuous. Discontinuities in the peripheral adhesive layer 143 may be provided by apertures or holes (not shown) in the adhesive. The apertures or holes in the adhesive of the peripheral adhesive layer 143 may be formed after application of the adhesive or by coating the adhesive in patterns. Apertures or holes in the adhesive of the peripheral adhesive layer 143 may also be sized to enhance the MVTR of the dressing 100.

[0085] In some embodiments, the dressing 100 may further include a discontinuous adhesive layer 127 (schematically depicted in FIG. 4B) at least partially covering each projection 126 of the manifold 110. The discontinuous adhesive layer 127 may include an adhesive that adhesively bonds each projection 126 to the drape 102. The discontinuous adhesive layer 127 may cover each projection 126 without adversely affecting fluid management provided by the plurality of fluid channels 130 and without blocking the plurality of perforations 128. The adhesive of the discontinuous adhesive layer 127 may include, for example, a medically acceptable, pressure-sensitive adhesive. Discontinuities in the discontinuous adhesive layer 127 may be provided similarly to the peripheral adhesive layer 143 described above. In some embodiments, the dressing 100 may include the peripheral adhesive layer 143, the discontinuous adhesive layer 127, or both.

[0086] Referring to FIGS. 2, 4A, 4B, and 5, as discussed above, the second major surface 124 is configured to face the tissue site. In some embodiments, the second major surface 124 may contact the tissue site. The second major surface 124 may be smooth to reduce or prevent discomfort to the tissue site. Specifically, the second major surface 124 may be devoid of any fluid channels (such as the plurality of fluid channels 130) extending along the plane 112 of the manifold 110.

[0087] In some embodiments, the manifold 110 further includes a bottom portion 150 disposed adjacent to the plurality of projections 126 and forming the second major surface 124. The bottom portion 150 may extend partly along the thickness 110T of the manifold 110. The bottom portion 150 may include a bottom edge 152 disposed around the second major surface 124. In some embodiments, the bottom edge 152 may be rounded. For example, the bottom edge 152 may be chamfered. The rounded shape of the bottom edge 152 may reduce stress and / or forces on or around the tissue site, especially during application of negative pressure to the tissue site via the dressing 100. This may reduce discomfort to the tissue site during negative therapy, thereby reducing or preventing tissue breakdown and blistering.

[0088] In some embodiments, the manifold 110 further includes a top portion 140 including the plurality of projections 126. The peripheral flange 142 may be disposed around and extend from the top portion 140. The manifold 110 may further include a perimeter edge 146 interfacing the top portion 140 with the peripheral flange 142 distal to the first major surface 122. In some embodiments, the perimeter edge 146 may be rounded. For example, the perimeter edge 146 may be chamfered. The rounded shape of perimeter edge 146 may reduce stress and / or forces on or around the tissue site, especially during application of negative pressure to the tissue site via the dressing 100. This may further reduce discomfort to the tissue site during negative therapy, thereby reducing or preventing tissue breakdown and blistering.

[0089] In some embodiments, the height 130H of each fluid channel 130 may be from 30% to 70% of the thickness HOT of the manifold 110. In some embodiments, the height 13 OH of each fluid channel 130 may be about 35% of the thickness HOT of the manifold 110. The height BOH of each fluid channel 130 being from 30% to 70% of the thickness HOT of the manifold 110 may ensure that the plurality of fluid channels 130 has desired fluid handling capabilities without compromising the structural integrity of the manifold 110.

[0090] In some embodiments, a distance 131 between adjacent fluid channels 130 from the plurality of fluid channels 130 along the longitudinal axis 114 may be at least twice the width BOW of each fluid channel 130. The distance 131 may correspond to a width of a corresponding projection 126 disposed between the adjacent fluid channels 130. The distance 131 being at least twice the width BOW of each fluid channel 130 may prevent collapse of the drape 102 into the plurality of fluid channels 130 during application of negative pressure, thereby ensuring optimal fluid management during use of the dressing 100 over a prolonged period of time.

[0091] In some embodiments, the width BOW of each fluid channel 130 may be at least twice a thickness TW (shown in FIG. 2) of the drape 102. In some embodiments, the width BOW of each fluid channel 130 may be at least three times, or at least four times the thickness TW of the drape 102. The width BOW of each fluid channel 130 being at least twice the thickness TW of the drape 102 may ensure that the plurality of fluid channels 130 allows efficient movement of fluids received from the tissue site.

[0092] Each perforation 128 defines a major dimension 128L along one of the longitudinal axis 114 and the transverse axis 116. That is, in some embodiments, the major dimension 128L may be along the longitudinal axis 114. In some other embodiments, the major dimension 128L may be along the transverse axis 116. In the illustrated embodiment of FIGS. 4A and 4B, the major dimension 128L of each perforation 128 is defined along the longitudinal axis 114.

[0093] In some embodiments, the major dimension 128L of each perforation 128 may be at least twice the width BOW of eachfluid channel 130 and at most thrice the width BOW of eachfluid channel 130. This may ensure optimal distribution of negative pressure to the tissue site and reduce or prevent reduction in the manifolding performance of the manifold 110 during use of the dressing 100 over a prolonged period of time.

[0094] In some embodiments, the manifold 110 may be a unitary molded component. Specifically, the plurality of fluid channels 130 and the plurality of perforations 128 may enable the manifold 110 to be formed as the unitary molded component. The plurality of fluid channels 130 and the plurality of perforations 128 may provide the manifold 110 with desirable fluid handling and negative pressure distribution capabilities while having a unitary molded structure. Due to the unitary molded structure of the manifold 110, the dressing 100 may be more economical and easier to manufacture and assemble as compared to conventional negative pressure dressings that have multi-layered manifolds or openfoam manifolds. In some embodiments, the manifold 110 may be made of a closed-cell foam. In some embodiments, the manifold 110 may be made of silicone. Any suitable moldable material may be used to form the manifold 110 as the unitary molded component.

[0095] In some embodiments, the release liner 106 (shown in FIG. 2) may be removably attached to the second major surface 124 of the manifold 110. The release liner 106 may be configured to be removed from the manifold 110 before placement of the manifold 110 directly on the tissue site, such that each perforation 128 is in direct fluid communication with the tissue site.

[0096] In some embodiments, one or more of the components of the dressing 100 may additionally be treated with an antimicrobial agent. For example, the manifold 110, or more specifically, the second major surface 124 of the manifold 110 may be coated with an antimicrobial agent. Suitable antimicrobial agents may include, for example, metallic silver, PHMB, iodine or its complexes and mixes such as povidone iodine, copper metal compounds, chlorhexidine, or some combination of these materials.

[0097] FIG. 6 illustrates a schematic exploded perspective view of a dressing 200 for treating a tissue site with negative pressure according to another embodiment of the present disclosure. The dressing 200 is similar to the dressing 100 of FIG. 2, with like elements designated by like reference characters. However, the dressing 200 includes an additional layer as compared to the dressing 100.

[0098] Specifically, in the illustrated embodiment of FIG. 6, the dressing 200 includes a sealing layer 212 coupled to the drape 102 and disposed adjacent to the second major surface 124 of the manifold 110. More specifically, in the illustrated embodiment of FIG. 6, the tissue interface 160 includes the manifold 110 and the sealing layer 212.

[0099] The sealing layer 212 includes one or more treatment apertures 214 aligned with the manifold 110 and a plurality of peripheral apertures 216 disposed around the one or more treatment apertures 214. The one or more treatment apertures 214 may be complementary or correspond to a surface area of the manifold 110. In the illustrated embodiment of FIG. 6, the one or more treatment apertures 214 includes one treatment aperture 214. The one treatment aperture 214 is complementary or corresponds to a surface area of the manifold 110, such that upon placement of the dressing 200 on the tissue site, at least a portion of the manifold 110 directly contacts the tissue site. In some embodiments, the one treatment aperture 214 may be complementary or correspond to a surface area of the manifold 110, such that upon placement of the dressing 200 on the tissue site, the peripheral flange 142 (shown in FIGS. 4 A, 4B, and 5) of the manifold 110 is disposed between the sealing layer 212 and the drape 102.

[0100] Further, the plurality of peripheral apertures 216 may be formed by cutting, perforating, punching, or by other suitable techniques for forming an aperture, opening, perforation, or hole in the sealing layer 212, including, but not limited to, using a single- or multiple-blade cutter, a laser, a water jet, a hot knife, a computer numeric control (CNC) cutter, a hot wire, local RF or ultrasonic energy, and / or a single-or multiple-punch tool. The plurality of peripheral apertures 216 may have a uniform distribution pattern, or may be randomly distributed on the sealing layer 212. The plurality of peripheral apertures 216 of the sealing layer 212 may have many shapes, including circles, squares, stars, ovals, polygons, slits, complex curves, rectilinear shapes, triangles, for example, or may have some combination of such shapes.

[0101] The sealing layer 212 may be formed from a soft, pliable material suitable for providing a fluid seal with the tissue site, such as a suitable gel material, and may have a substantially flat surface. For example, the sealing layer 212 may include, without limitation, a silicone gel, a soft silicone, hydrocolloid, hydrogel, polyurethane gel, polyolefin gel, hydrogenated styrenic copolymer gel, a foamed gel, a soft closed cell foam such as polyurethanes and polyolefins coated with an adhesive, polyurethane, polyolefin, or hydrogenated styrenic copolymers. In some embodiments, the sealing layer 212 may have a thickness in a range of about 200 microns to about 1000 microns. In some embodiments, the sealing layer 212 may have a hardness between about 5 Shore OO and about 80 Shore 00. The sealing layer 212 may include hydrophobic or hydrophilic materials.

[0102] In some embodiments, the release liner 106 may be removably attached to the sealing layer 212 opposite to the manifold 110. The release liner 106 may be configured to be removed from the sealing layer 212 before placement of the sealing layer 212 directly on the tissue site, such that each perforation 128 (shown in FIG. 3) of the manifold 110 is in fluid communication with the tissue site via the treatment aperture 214. In some embodiments, the release liner 106 may include a release agent disposed on a side of the release liner 106 that is configured to contact the sealing layer 212.

[0103] FIG. 7 illustrates a schematic exploded perspective view of a dressing 300 for treating a tissue site with negative pressure according to another embodiment of the present disclosure. The dressing 300 is substantially similar to the dressing 200 of FIG. 6, with like elements designated by like numbers. However, the sealing layer 212 of the dressing 300 has a different configuration than that of the dressing 200.

[0104] Specifically, in the illustrated embodiment of FIG. 7, the one or more treatment apertures 214 includes a plurality of treatment apertures 214. The plurality of treatment apertures 214 may be complementary or correspond to a surface area of the manifold 110, such that upon placement of the dressing 300 on the tissue site, the manifold 110 is spaced apart from the tissue site by the sealing layer 212. In such embodiments, each perforation 128 (shown in FIG. 3) of the manifold 110 may be in indirect fluid communication with the tissue site via the plurality of treatment apertures 214.

[0105] FIG. 8 illustrates a schematic cross-sectional view of a portion of a dressing 400 for treating a tissue site with negative pressure according to another embodiment of the present disclosure. The dressing 400 includes a manifold 410. The manifold 410 includes a first major surface 412 and a second major surface 414 opposite to the first major surface 412 and spaced apart from the first major surface 412. The second major surface 414 is configured to face the tissue site.

[0106] The manifold 410 further includes a plurality of perforations 428 extending through the manifold 410 from the first major surface 412 to the second major surface 414. In other words, each of the plurality of perforations 428 may be a through-perforation. In some embodiments, each perforation 428 may be a slit. The slit may have a linear, curved, or otherwise irregular geometry.

[0107] The dressing 400 further includes a drape 402 disposed adjacent to and coupled to the first major surface 412. In some embodiments, the drape 402 may be coupled to the first major surface 412 of the manifold 410 via an adhesive. In some embodiments, the drape 402 may be coupled to the first major surface 412 along a perimeter of the drape 402.

[0108] The drape 402 covers the first major surface 412. The drape 402 includes a plurality of projections 426 extending from the first major surface 412 of the manifold 410 and a plurality of recesses 420 alternating with the plurality of projections 426.

[0109] The drape 402 further includes a plurality of fluid channels 430. Each fluid channel 430 from the plurality of fluid channels 430 is defined by a corresponding projection 426 from the plurality of projections 426. Each fluid channel 430 is in fluid communication with at least some of the plurality of perforations 428 of the manifold 410. In some embodiments, the plurality of fluid channels 430 may have a similar configuration to that of the plurality of fluid channels 130 described above with reference to FIGS. 3, 4 A, and 4B.

[0110] The drape 402 further includes a drape aperture 404 extending therethrough. The drape aperture 404 is configured to be coupled to a dressing interface (e.g., the dressing interface 60 shown in FIG. 2) that is in fluid communication with the negative pressure source (shown in FIG. 1).

[0111] Upon placement of the dressing 400 on the tissue site, at least some of the plurality of perforations 428 may be in fluid communication with the tissue site. The plurality of perforations 428 may distribute negative pressure from the negative pressure source 25 (shown in FIG. 1) to the tissue site. As a result, fluids (i.e., wound exudate) from the tissue site may move through the plurality of perforations 428 of the manifold 410 to the plurality of fluid channels 430 of the drape 402. The plurality of fluid channels 430 of the drape 402 may manage the fluids and facilitate removal of the fluids through the dressing interface. The plurality of fluid channels 430 of the drape 402 and the plurality of perforations 428 of the manifold 410 may together ensure optimal fluid management during use of the dressing 400 over a prolonged period of time (e.g., greater than 3 days, greater than 5 days, or greater than 7 days). This may promote healing of the tissue site more quickly than current standard of care.

[0112] The drape 402 may include a first drape major surface 406 and a second drape major surface 408 opposite to the first drape major surface 406. The second drape major surface 408 may face the first major surface 412 of the manifold 410. The drape aperture 404 may extend from the first drape major surface 406 to the second drape major surface 408.

[0113] The drape 402 may further include a plurality of connecting portions 422. Each connecting portion 422 from the plurality of connecting portions 422 may be disposed between and connect adjacent projections 426 from the plurality of projections 426. The second drape major surface 408 corresponding to the connecting portions 422 may at least partially contact the first major surface 412 of the manifold 410. In some embodiments, the second drape major surface 408 corresponding to the connecting portions 422 may be coupled to the first major surface 412 of the manifold 410, for example, via an adhesive.

[0114] The drape 402 may define a thickness 402T between the first drape major surface 406 and the second drape major surface 408. Further, each fluid channel 430 may define a width 430W perpendicular to the thickness 402T and a height 430H parallel to the thickness 402T.

[0115] In some embodiments, the width 430W of each fluid channel 430 may be greater than the thickness 402T of the drape 402. In some embodiments, the height 430H of each fluid channel 430 may be greater than the thickness 402T of the drape 402. This may ensure that the plurality of fluid channels 430 allows efficient movement of fluids received from the tissue site.

[0116] The plurality of projections 426 and the plurality of recesses 420 of the drape 402 may be formed by any suitable method, such as thermoforming, vacuum forming, cold forming, rotary compression forming, and the like. In some embodiments, the manifold 410 may be a unitary molded component. Due to the unitary molded structure of the manifold 410, the dressing 400 may be more economical and easier to manufacture and assemble as compared to conventional negative pressure dressings that have multi-layered manifolds or open-foam manifolds. In some embodiments, the manifold 410 may be made of a closed-cell foam. In some embodiments, the manifold 410 may be made of silicone. Any suitable moldable material may be used to form the manifold 410 as the unitary molded component. In some embodiments, the dressing 400 may further include a sealing layer (similar to the sealing layer 212 described above with reference to FIGS. 6 and 7) coupled to the second major surface 414 of the manifold 410 and / or the second drape major surface 408 of the drape 402.

[0117] Referring to FIGS. 1 to 8, the system 10 may include one of the dressings 100, 200, 300, 400. The system 10 may be suitable for providing negative pressure therapy. Due to the unitary molded stmcture of the manifolds 110, 410 of the dressings 100, 200, 300, 400, the dressings 100, 200, 300, 400 may be easy to manufacture and assemble in comparison to conventional negative pressure dressings that have multi-layered manifolds or open-foam manifolds.

[0118] The dressings 100, 200, 300, 400 may also increase formation of granulation tissue at the tissue site (i.e., provide faster healing). Specifically, the dressings 100, 200, 300, 400 may augment and accelerate growth of new tissue at the tissue site. The dressings 100, 200, 300, 400 may also be suitable for long-term wear (e.g., greater than 3 days, greater than 5 days, or greater than 7 days). Specifically, the dressings 100, 200, 300, 400 may be used to treat the tissue site for a prolonged time period (e.g., greater than 3 days, greater than 5 days, or greater than 7 days) before needing replacement. The dressings 100, 200, 300, 400 may maintain their fluid handling and manifolding capabilities during the prolonged time period. Further, the dressings 100, 200, 300, 400 may reduce tissue-ingrowth over the prolonged time period with reduced slough and maintained granulation tissue. Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

[0119] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and / or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.

Claims

CLAIMSWhat is claimed is:

1. A dressing for treating a tissue site with negative pressure, the dressing comprising: a manifold defining a plane, a longitudinal axis disposed in the plane and extending along a length of the manifold, a transverse axis disposed in the plane and extending perpendicular to the longitudinal axis, and a thickness normal to the plane, the manifold comprising: a first major surface; a second major surface opposite to the first major surface and spaced apart from the first major surface with respect to the thickness of the manifold, wherein the second major surface is configured to face the tissue site; a plurality of projections disposed at the first major surface and spaced apart from each other, the plurality of projections defining a plurality of fluid channels therebetween, the plurality of projections at least partly forming the first major surface, wherein each fluid channel from the plurality of fluid channels extends along the plane of the manifold and defines a width along the plane of the manifold and a height normal to the plane, and wherein each fluid channel further extends partly from the first major surface towards the second major surface, such that the height of each fluid channel is less than the thickness of the manifold; and a plurality of perforations extending through the manifold from the first major surface to the second major surface, each perforation from the plurality of perforations extending at least partly through a corresponding projection from the plurality of projections; and a drape disposed adjacent to and coupled to the first major surface, the drape covering the first major surface, the drape comprising a drape aperture extending therethrough and configured to be coupled to a dressing interface that is in fluid communication with a negative pressure source.

2. The dressing of claim 1, wherein each fluid channel defines a width along the plane of the manifold, wherein each perforation defines a major dimension along one of the longitudinal axis and the transverse axis, and wherein the major dimension of each perforation is at least twice the width of each fluid channel and at most thrice the width of each fluid channel.

3. The dressing of claim 1, wherein the second major surface is devoid of any fluid channels extending along the plane of the manifold.

4. The dressing of claim 1, wherein the manifold further comprises a bottom portion disposed adjacent to the plurality of projections and forming the second major surface, the bottom portion extending partly along the thickness of the manifold, wherein the bottom portion comprises a bottom edge disposed around the second major surface, and wherein the bottom edge is rounded.

5. The dressing of claim 1, wherein the manifold further comprises a peripheral flange surrounding the plurality of fluid channels and partly forming the first major surface, and wherein the peripheral flange is coupled to the drape.

6. The dressing of claim 5, further comprising a peripheral adhesive layer at least partially covering the peripheral flange, the peripheral adhesive layer comprising an adhesive that adhesively bonds the peripheral flange to the drape.

7. The dressing of claim 5, wherein the manifold comprises a top portion comprising the plurality of projections, the peripheral flange disposed around and extending from the top portion, the manifold further comprising a perimeter edge interfacing the top portion with the peripheral flange distal to the first major surface, wherein the perimeter edge is rounded.

8. The dressing of claim 1, further comprising a discontinuous adhesive layer at least partially covering each projection, the discontinuous adhesive layer comprising an adhesive that adhesively bonds each projection to the drape.

9. The dressing of claim 1, wherein a distance between adjacent fluid channels from the plurality of fluid channels along the longitudinal axis is at least twice the width of each fluid channel.

10. The dressing of claim 1, wherein the height of each fluid channel is from 30% to 70% of the thickness of the manifold.

11. The dressing of claim 1 , wherein the width of each fluid channel is at least twice a thickness of the drape.

12. The dressing of claim 1, wherein each perforation is a slit.

13. The dressing of claim 1, wherein the plurality of fluid channels comprises: a collection channel; and a plurality of converging channels spaced apart from each other and converging at the collection channel, wherein each converging channel from the plurality of converging channels is disposed in fluid communication with the collection channel.

14. The dressing of claim 13, wherein the plurality of fluid channels further comprises a plurality of cross channels spaced apart from each other and the collection channel, wherein each cross channel intersects with each converging channel, such that the plurality of converging channels and the plurality of cross channels form a grid.

15. The dressing of claim 14, wherein each cross channel is oval.

16. The dressing of claim 14, wherein the plurality of projections comprises a peripheral projection surrounding the rest of the plurality of projections, and wherein each converging channel extends from the peripheral projection to the collection channel.

17. The dressing of claim 16, wherein the peripheral projection and one or more adjacent projections from the plurality of projections define a peripheral cross channel from the plurality of cross channels, the peripheral cross channel surrounding the rest of the plurality of cross channels.

18. The dressing of claim 13, wherein each converging channel is linear.

19. The dressing of claim 13, wherein at least one converging channel from the plurality of converging channels is inclined obliquely to the longitudinal axis.

20. The dressing of claim 13, wherein at least one converging channel from the plurality of converging channels is parallel to the transverse axis.

21. The dressing of claim 13, wherein the drape aperture is aligned with the collection channel.

22. The dressing of claim 1, further comprising a sealing layer coupled to the drape and disposed adjacent to the second major surface of the manifold, the sealing layer comprising one or more treatment apertures aligned with the manifold and a plurality of peripheral apertures disposed around the one or more treatment apertures.

23. The dressing of claim 22, further comprising a release liner removably attached to the sealing layer opposite to the manifold, wherein the release liner is configured to be removed from the sealing layer before placement of the sealing layer directly on the tissue site, such that each perforation of the manifold is in fluid communication with the tissue site via the one or more treatment apertures.

24. The dressing of claim 1, wherein the manifold is a unitary molded component.

25. The dressing of claim 1, wherein the manifold is made of a closed-cell foam.

26. The dressing of claim 1, wherein the manifold is made of silicone.

27. The dressing of claim 1, further comprising a release liner removably attached to the second major surface of the manifold, wherein the release liner is configured to be removed from the manifold before placement of the manifold directly on the tissue site, such that each perforation is in direct fluid communication with the tissue site.

28. The dressing of claim 1, wherein the manifold further comprises a plurality of channel walls corresponding to the plurality of fluid channels, such that each channel wall forms a corresponding fluid channel from the plurality of fluid channels, and wherein at least some of the plurality of perforations at least partially extend through corresponding channel walls from the plurality of channel walls.

29. A system for providing negative pressure therapy, the system comprising: the dressing of claim 1; a dressing interface coupled to the drape and disposed in fluid communication with the drape aperture; a fluid conductor coupled to and disposed in fluid communication with the dressing interface; anda negative pressure source fluidly coupled to the fluid conductor.

30. A dressing for treating a tissue site with negative pressure, the dressing comprising: a manifold comprising: a first major surface; a second major surface opposite to the first major surface and spaced apart from the first major surface, wherein the second major surface is configured to face the tissue site; and a plurality of perforations extending through the manifold from the first major surface to the second major surface; and a drape disposed adjacent to and coupled to the first major surface, the drape covering the first major surface, the drape comprising: a plurality of projections extending from the first major surface of the manifold and a plurality of recesses alternating with the plurality of projections; a plurality of fluid channels, wherein each fluid channel from the plurality of fluid channels is defined by a corresponding projection from the plurality of projections, wherein each fluid channel is in fluid communication with at least some of the plurality of perforations of the manifold; and a drape aperture extending therethrough and configured to be coupled to a dressing interface that is in fluid communication with a negative pressure source.

31. The dressing of claim 30, wherein each perforation is a slit.

32. The dressing of claim 30, wherein the drape further comprises a first drape major surface and a second drape major surface opposite to the first drape major surface, the second drape major surface facing the first major surface of the manifold.

33. The dressing of claim 32, wherein the drape comprises a plurality of connecting portions, wherein each connecting portion from the plurality of connecting portions is disposed between and connects adjacent projections from the plurality of projections, wherein the second drape major surface corresponding to the connecting portions at least partially contacts the first major surface of the manifold.

34. The dressing of claim 32, wherein the drape defines a thickness between the first drape major surface and the second drape major surface, wherein each fluid channel defines a width perpendicular to the thickness and a height parallel to the thickness, wherein the width of each fluid channel is greater than the thickness of the drape, and wherein the height of each fluid channel is greater than the thickness of the drape.

35. A system for providing negative pressure therapy, the system comprising: the dressing of claim 30;a dressing interface coupled to the drape and disposed in fluid communication with the drape aperture; a fluid conductor coupled to and disposed in fluid communication with the dressing interface; and a negative pressure source fluidly coupled to the fluid conductor.

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