Patent Description:
There is also widespread acceptance that cleansing a tissue site can be highly beneficial for new tissue growth. For example, a wound or a cavity can be washed out with a liquid solution for therapeutic purposes. These practices are commonly referred to as "irrigation" and "lavage" respectively. "Instillation" is another practice that generally refers to a process of slowly introducing fluid to a tissue site and leaving the fluid for a prescribed period of time before removing the fluid. For example, instillation of topical treatment solutions over a wound bed can be combined with negative-pressure therapy to further promote wound healing by loosening soluble contaminants in a wound bed and removing infectious material. As a result, soluble bacterial burden can be decreased, contaminants removed, and the wound cleansed.

While the clinical benefits of negative-pressure therapy and/or instillation therapy are widely known, improvements to therapy systems, components, and processes may benefit healthcare providers and patients. <CIT> discloses a reduced pressure treatment system that includes a distribution manifold having a backing substrate with a first side and a second side and a plurality of protrusions positioned on the first side of the backing substrate. Each of the protrusions includes a substantially circular cross-sectional shape and has a diameter of between about <NUM> and <NUM> millimeters, the backing substrate having a plurality of apertures formed therein to allow fluid communication between the first side and the second side opposite the first side. A reduced pressure source is fluidly connected to the apertures of the backing substrate to deliver the reduced pressure through the apertures, between the protrusions, and to a tissue site. <CIT> discloses a reduced-pressure treatment system which includes an isolation device for isolating a tissue site from surrounding tissue for reduced-pressure treatment that is formed from a first material having a first bio-absorption term and at least a second material having a second and different bio-absorption term. <CIT> discloses systems for treating wounds that utilize dressings having closed cells and perforations or apertures in a negative-pressure and instillation therapy environment. <CIT> discloses a wound shield that includes a conformable frame to circumscribe a wound and warm water circulating system to maintain a warm environment. <CIT> disclose wound fillers that preferentially collapse in one direction as compared to another direction.

There is provided a system for treating a tissue site with reduced pressure, comprising a conformable dressing comprising: a plurality of discrete manifold members, each discrete manifold member including a first surface and a second surface, the first surface separated from the second surface by a perimeter wall; and a carrier including a first side positioned facing the tissue site and a second side positioned opposite the first side. The carrier is expandable between a relaxed state and an expanded state, wherein a separation distance between the perimeter wall of a first of the plurality of discrete manifold members and the perimeter wall of a second of the plurality of discrete manifold members is greater in the expanded state than in the relaxed state. The system comprises an attachment device comprising a plurality of separate points each positioned between the first surface of each of the discrete manifold members and the second side of the carrier, wherein the first surface of each of the discrete manifold members is coupled to the second side of the carrier by the attachment device. The system comprises a sealing member covering the conformable dressing to create a sealed space at the tissue site, and a reduced pressure source coupled in fluid communication with the sealed space. A selection of optional features is set out in the dependent claims.

The following description of example embodiments enables a person skilled in the art to make and use the subject matter set forth in the appended claims. Certain details already known in the art may be omitted. Therefore, the following detailed description is illustrative and non-limiting.

However, as recognized by those skilled in the art, this frame of reference is merely a descriptive expedient rather than a strict prescription.

<FIG> is a block diagram of an example embodiment of a therapy system <NUM> that can provide negative-pressure therapy with instillation of topical treatment solutions to a tissue site in accordance with this specification.

The term "tissue site" in this context broadly refers to a wound, defect, or other treatment target located on or within tissue, including, but not limited to, bone tissue, adipose tissue, muscle tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, or ligaments. A wound may include chronic, acute, traumatic, subacute, and dehisced wounds, partial-thickness burns, 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 the growth of additional tissue. For example, negative pressure may be applied to a tissue site to grow additional tissue that may be harvested and transplanted.

Continuing with <FIG>, the therapy system <NUM> may include a source or supply of negative pressure, such as a reduced pressure source or negative-pressure source <NUM>, and one or more distribution components. A distribution component may be detachable, disposable, reusable, or recyclable. A dressing, such as a conformable dressing <NUM>, and a fluid container, such as a container <NUM>, are examples of distribution components that may be associated with some examples of the therapy system <NUM>.

A negative-pressure supply, such as the negative-pressure source <NUM>, 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 <NUM> may vary according to therapeutic requirements, the pressure is generally a low vacuum, also commonly referred to as a rough vacuum, between -<NUM> Hg (-<NUM> Pa) and -<NUM> Hg (-<NUM> kPa). Common therapeutic ranges are between -<NUM> Hg (-<NUM> kPa) and -<NUM> Hg (-<NUM> kPa).

The process of reducing pressure may be described illustratively herein as "delivering," "distributing," or "generating" negative pressure, for example. In general, exudate and other fluid flow toward lower pressure along a fluid path. Thus, the term "downstream" typically implies a location 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 a location relatively further away from a source of negative pressure or closer to a source of positive pressure. Similarly, certain features may be described 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.

Negative pressure applied to a tissue site in a 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 <NUM>.

As illustrated in the example of <FIG>, the conformable dressing <NUM> may include a tissue interface layer or a carrier <NUM>, and a plurality of filler elements or manifold members <NUM>. Herein, references made to the carrier <NUM> may be similarly or analogously applicable to the interface layer, and references made to the manifold members <NUM> may be similarly or analogously applicable to the filler elements. In some embodiments, the conformable dressing <NUM> may include or be used with a sealing member <NUM> as part of the therapy system <NUM>. The sealing member <NUM> may be capable of creating a sealed space <NUM> at a tissue site <NUM>. An example of the tissue site <NUM> is shown as a knee in <FIG>. In some embodiments, the conformable dressing <NUM> may be provided or used without the negative-pressure source <NUM> or other components of the therapy system <NUM>.

In some embodiments, the sealing member <NUM> may provide a bacterial barrier and protection from physical trauma. The sealing member <NUM> 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 sealing member <NUM> may comprise or consist of, 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 sealing member <NUM> may have a high moisture-vapor transmission rate (MVTR) in some applications. For example, the MVTR may be at least <NUM> 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 <NUM> and <NUM>% relative humidity (RH). In some embodiments, an MVTR up to <NUM>,<NUM> grams per square meter per twenty-four hours may provide effective breathability and mechanical properties.

In some example embodiments, the sealing member <NUM> may be a polymer drape, 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 <NUM>-<NUM> microns. For permeable materials, the permeability generally should be low enough that a desired negative pressure may be maintained. The sealing member <NUM> may comprise, for example, one or more of the following materials: polyurethane (PU), such as hydrophilic polyurethane; cellulosics; hydrophilic polyamides; polyvinyl alcohol; polyvinyl pyrrolidone; hydrophilic acrylics; silicones, such as hydrophilic silicone elastomers; 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 <NUM> Company, Minneapolis Minnesota; polyurethane (PU) drape, commercially available from Avery Dennison Corporation, Pasadena, California; polyether block polyamide copolymer (PEBAX), for example, from Arkema S. , Colombes, France; and Inspire <NUM> and Inpsire <NUM> polyurethane films, commercially available from Expopack Advanced Coatings, Wrexham, United Kingdom. In some embodiments, the sealing member <NUM> may comprise INSPIRE <NUM> having an MVTR (upright cup technique) of <NUM>/m<NUM>/<NUM> hours and a thickness of about <NUM> microns.

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

In some embodiments, for example, a dressing interface may facilitate coupling a fluid conductor to the dressing <NUM> and the sealed space <NUM> through the sealing member <NUM>.

Operating parameters may include the power applied to the negative-pressure source <NUM>, the pressure generated by the negative-pressure source <NUM>, or the pressure distributed to the dressing <NUM>, for example.

Sensors, such as the first sensor <NUM> and the second sensor <NUM> may be any apparatus operable to detect or measure a physical phenomenon or property, and generally provide a signal indicative of the phenomenon or property that is detected or measured.

In some embodiments, the controller <NUM> may receive and process data from one or more sensors, such as the first sensor <NUM>. The controller <NUM> may also control the operation of one or more components of the therapy system <NUM> to manage the pressure delivered to the dressing <NUM> or components of the dressing <NUM>. In some embodiments, controller <NUM> 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 dressing <NUM>. 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 <NUM>. 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 <NUM> can operate the negative-pressure source <NUM> 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 dressing <NUM>.

The therapy system <NUM> may also include a source of instillation solution. For example, a solution source <NUM> may be fluidly coupled to the dressing <NUM>, as illustrated in the example embodiment of <FIG>. The solution source <NUM> may be fluidly coupled to a positive-pressure source such as a positive-pressure source <NUM>, a negative-pressure source such as the negative-pressure source <NUM>, or both in some embodiments. A regulator, such as an instillation regulator <NUM>, may also be fluidly coupled to the solution source <NUM> and the dressing <NUM> to ensure proper dosage of instillation solution, such as saline, to a tissue site. For example, the instillation regulator <NUM> may comprise a piston that can be pneumatically actuated by the negative-pressure source <NUM> 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 <NUM> may be coupled to the negative-pressure source <NUM>, the positive-pressure source <NUM>, or both, to control dosage of instillation solution to a tissue site. In some embodiments, the instillation regulator <NUM> may also be fluidly coupled to the negative-pressure source <NUM> through the dressing <NUM>, as illustrated in the example of <FIG>.

Further, in some embodiments, the controller <NUM> may receive and process data, such as data related to instillation solution provided to the dressing <NUM>. Such data may include the type of instillation solution prescribed by a clinician, the volume of fluid or solution to be instilled to a tissue site ("fill volume"), and the amount of time prescribed for leaving solution at a tissue site ("dwell time") before applying a negative pressure to the tissue site. The fill volume may be, for example, between <NUM> and <NUM>, and the dwell time may be between one second to <NUM> minutes. The controller <NUM> may also control the operation of one or more components of the therapy system <NUM> to instill solution.

For example, the controller <NUM> may manage fluid distributed from the solution source <NUM> to dressing <NUM> or components of the dressing <NUM>. In some embodiments, fluid may be instilled to a tissue site by applying a negative pressure from the negative-pressure source <NUM> to reduce the pressure at the tissue site and drawing solution into the dressing <NUM>. In some embodiments, solution may be instilled to a tissue site by applying a positive pressure from the positive-pressure source <NUM> to move solution from the solution source <NUM> to the dressing <NUM>. Additionally or alternatively, the solution source <NUM> may be elevated to a height sufficient to allow gravity to move solution into dressing <NUM>.

Some components of the therapy system <NUM> 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 <NUM> may be combined with the controller <NUM>, the solution source <NUM>, and other components into a therapy unit.

Referring to the example embodiments of <FIG>, the dressing <NUM> may be configured, by way of example and without limitation, as a dressing 110a, a dressing, 110b, or a dressing 110c. As illustrated in <FIG>, the dressing 110a may include the sealing member <NUM> positioned to cover a dressing filler <NUM>. The dressing filler <NUM> may include the manifold members <NUM> and the carrier <NUM>. Although the dressing filler <NUM> is shown in <FIG> as part of the dressing <NUM>, the dressing filler <NUM> may itself be referred to as a dressing in some embodiments, such as, for example, when the dressing filler <NUM> is used without the sealing member <NUM>. The attachment device <NUM> may be coupled to or configured to be coupled to at least a periphery <NUM> of the sealing member <NUM>. In some embodiments, the attachment device <NUM> may be coating covering an entire surface of the sealing member <NUM> that is configured to face the tissue site <NUM>. The attachment device <NUM> may be configured to couple the sealing member <NUM> to tissue at or around the tissue site <NUM> to provide the sealed space <NUM>. The manifold members <NUM> and the carrier <NUM> may be disposed in the sealed space <NUM> as shown in <FIG>. The attachment device <NUM> may also be optionally positioned on a side of the carrier <NUM> configured to face the tissue site <NUM> to assist with deployment and positioning of the carrier <NUM> and other components of the dressing 110a at the tissue site <NUM>.

As illustrated in <FIG>, the dressing 110b may include the sealing member <NUM> positioned to cover the dressing filler <NUM> including the manifold members <NUM> and the carrier <NUM>. The attachment device <NUM> may be coupled to or configured to be coupled between at least a periphery <NUM> of the sealing member <NUM> and a periphery <NUM> of a base layer <NUM>. In other embodiments, the periphery <NUM> of the sealing member <NUM> and the periphery <NUM> of the base layer <NUM> may be coupled by a heat bond, flame lamination, or other suitable device or method. The sealing member <NUM> and the base layer <NUM> may form an enclosure surrounding or encapsulating the manifold members <NUM> and the carrier <NUM>. The base layer <NUM> may be formed from a fluid permeable material and/or a material including perforations or fenestrations configured to provide fluid communication relative to the tissue site <NUM>. The attachment device <NUM> may also be optionally positioned on a side of the base layer <NUM> configured to face the tissue site <NUM> to assist with deployment and positioning of the base layer <NUM> and other components of the dressing 110b at the tissue site <NUM>.

By way of example, suitable materials for the base layer <NUM> may include, without limitation, a medical grade <NUM>-way or <NUM>-way stretch fabric, such as INTERDRY™, available from Milliken and Company of Spartanburg, South Carolina, or LYCRA™, available from Koch Industries of North Carolina. Other suitable materials may include, without limitation, an elastic polyurethane fiber or fabric, elastane, spandex, a polyurethane film, silicone, silicone with an elastic scrim layer, or hydrocolloid.

As illustrated in <FIG>, the dressing 110c may include the sealing member <NUM> positioned to cover the manifold members <NUM> and the carrier <NUM>. The attachment device <NUM> may be coupled to or configured to be coupled between at least a periphery <NUM> of the sealing member <NUM> and a periphery <NUM> of the carrier <NUM>. In other embodiments, the periphery <NUM> of the sealing member <NUM> and the periphery <NUM> of the carrier <NUM> may be coupled by a heat bond, flame lamination or other suitable device or method. The sealing member <NUM> and the carrier <NUM> may form an enclosure surrounding or encapsulating the manifold members <NUM> and the carrier <NUM>.

Referring to <FIG>, the dressing filler <NUM> may include a plurality of the manifold members <NUM> and the carrier <NUM>. Herein, the manifold members <NUM> may also be referred to as filler elements <NUM> including similar or analogous features, and the carrier <NUM> may also be referred to as a tissue interface layer <NUM> including similar or analogous features. Each of the manifold members <NUM> may include a first surface <NUM> and a second surface <NUM>. The first surface <NUM> may be separated from the second surface <NUM> by a thickness <NUM> and a perimeter wall <NUM> extending along or around the thickness <NUM> between the first surface <NUM> and the second surface <NUM>. The first surface <NUM> of the manifold members <NUM> may face opposite the second surface <NUM>.

The carrier <NUM> may include a first side <NUM> and a second side <NUM>. The first side <NUM> of the carrier <NUM> may be configured to be positioned facing the tissue site <NUM>. The second side <NUM> of the carrier may be positioned opposite the first side <NUM> of the carrier <NUM> and configured to be facing outward or away from the tissue site <NUM>. The first surface <NUM> of each of the manifold members <NUM> may be coupled to the second side <NUM> of the carrier <NUM> as shown in <FIG>. One or more of the manifold members <NUM> may be individually moveable relative to one another when coupled to the second side <NUM> of the carrier <NUM>.

The manifold members <NUM> is coupled to the carrier <NUM> by the attachment device <NUM> illustrated in <FIG>. The attachment device <NUM> is provided as separate connecting dots, points, portions, or segments positioned between or along the contact surface between the manifold members <NUM> and the carrier <NUM> as shown in <FIG>, which may enhance or increase an amount of stretch or expansion that is possible between the manifold members <NUM>.

The carrier <NUM> and the manifold members <NUM> may be manufactured in roll format or in any suitable shape to fit a particular tissue site. A sacrificial backing layer may be used during manufacture to support the manifold members <NUM> as they are coupled to the carrier <NUM>. In some embodiments, a manifold layer may be coupled to the carrier <NUM> and the manifold layer may be subsequently kiss-cut to a depth of <NUM>% or through an entire thickness of the manifold layer to form the manifold members <NUM>. In some embodiments, a manifold layer may be cut to a depth of <NUM>% to form the manifold members <NUM> with <NUM>% of the thickness <NUM> measured from the first surface <NUM> of the manifold members <NUM> coupled to each other or one another for support.

In some embodiments, the carrier <NUM> may include a stretchable material having elastic properties. The stretchable material may be configured to stretch in at least one direction, and may be formed as a layer or sheet. In some embodiments, the carrier <NUM> may be configured to stretch in at least one direction up to about <NUM> percent in length such that the carrier <NUM> has a stretched length that is up to about <NUM> times longer than a relaxed length in at least one direction.

By way of example, suitable materials for the carrier <NUM> may include, without limitation, a medical grade <NUM>-way or <NUM>-way stretch fabric, such as INTERDRY™, available from Milliken and Company of Spartanburg, South Carolina, or LYCRA™, available from Koch Industries of North Carolina. A <NUM>-way stretch fabric may be configured to stretch in one direction, and a <NUM>-way stretch fabric may be configured to stretch in two directions. Other suitable materials may include, without limitation, an elastic polyurethane fiber or fabric, elastane, spandex, a polyurethane film, silicone, or silicone with an elastic scrim layer. Fenestrations may be disposed through the carrier layer <NUM> to enhance or to provide elastic properties or stretch. The fenestrations may additionally enhance or provide fluid permeability through the carrier layer <NUM>.

The carrier <NUM> is expandable between a relaxed state shown in <FIG> and an expanded state or a stretched state shown in <FIG>. A direction of stretch, expansion, or contraction of the carrier <NUM> may be coplanar to the material, fabric, sheet, or film that may form the carrier <NUM>. For example, a direction <NUM> of stretch or expansion shown in <FIG> may lie along or in the same plane as the carrier <NUM>. The direction <NUM> in <FIG> additionally provides an example of <NUM>-way stretch described above, which is along one direction or line. An example of <NUM>-way stretch described above would additionally include stretch along another direction or line extending into and out of the page of <FIG>, for example.

A separation distance <NUM> between a first perimeter wall 173a of one of the manifold members <NUM> and a second perimeter wall 173b of another of the manifold members <NUM> is greater in the expanded state or stretched state than the relaxed state. Similarly, the separation distance <NUM> between a first exterior border 178a of one of the discrete manifold members <NUM> and a second exterior border 178b of another of the discrete manifold members <NUM> may be greater in the expanded state or the stretched state than the relaxed state. Further, in some embodiments, the first side <NUM> of the carrier <NUM> may optionally include the attachment device <NUM>, such as an adhesive, to assist with placement and positioning of the carrier at the tissue site <NUM>.

In some embodiments, the manifold members <NUM> may be discrete manifold members <NUM>. For example, one or more of the plurality of discrete manifold members <NUM> may be isolated or detached from each other or one another. In some embodiments, the perimeter wall <NUM> of the manifold members <NUM> may define an exterior border <NUM> that separates the manifold members <NUM> from each other or one another. Further, in some embodiments, one or more of the perimeter walls <NUM> of the manifold members <NUM> may be separated from each other or one another along the entire thickness <NUM> extending from the first surface <NUM> of the manifold members <NUM> to the second surface <NUM>.

In other embodiments, less than <NUM> percent of the thickness <NUM> of one or more of the manifold members <NUM> may be coupled to the thickness <NUM> of another of the manifold members <NUM>. In such an embodiment, less than <NUM> percent of the thickness <NUM> measured from the first surface <NUM> of one or more of the manifold members <NUM> may be coupled to a corresponding amount of the thickness <NUM> measured from the first surface <NUM> of another of the manifold members <NUM>. Upon deployment at the tissue site <NUM>, the manifold members <NUM> in this embodiment may be configured to stretch apart or tear apart from each other or one another.

Further, in some embodiments, the manifold members <NUM> may include or be formed from blocks of a porous material, such as, for example, foam, that may be configured to communicate fluid. A manifold in this context may comprise or consist essentially of a device for collecting or distributing fluid. For example, a manifold may be adapted to receive negative pressure from a source and to distribute negative pressure, 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.

In some illustrative embodiments, a manifold may comprise a plurality of pathways, which can be interconnected to improve distribution or collection of fluids. In some illustrative embodiments, a manifold may comprise or consist essentially of a porous material having interconnected fluid pathways. Examples of suitable porous material that can be adapted to form interconnected fluid pathways, such as channels, may include cellular foam, including open-cell foam such as reticulated foam; porous tissue collections; and other porous material such as gauze or felted mat that generally include pores, edges, and/or walls. Liquids, gels, and other foams may also include or be cured to include apertures and fluid pathways. In some embodiments, a manifold may additionally or alternatively comprise projections that form interconnected fluid pathways. For example, a manifold may be molded to provide surface projections that define interconnected fluid pathways.

In some embodiments, the manifold members <NUM> may comprise or consist essentially of reticulated foam having pore sizes and free volume that may vary according to needs of a prescribed therapy. For example, reticulated foam having a free volume of at least <NUM>% may be suitable for many therapy applications, and foam having an average pore size in a range of <NUM>-<NUM> microns (<NUM>-<NUM> pores per inch) may be particularly suitable for some types of therapy. The tensile strength of the manifold members <NUM> may also vary according to needs of a prescribed therapy. For example, the tensile strength of foam may be increased for instillation of topical treatment solutions. The <NUM>% compression load deflection of the manifold members <NUM> may be at least <NUM> pounds per square inch, and the <NUM>% compression load deflection may be at least <NUM> pounds per square inch. In some embodiments, the tensile strength of the manifold members <NUM> may be at least <NUM> pounds per square inch. The manifold members <NUM> may have a tear strength of at least <NUM> pounds per inch. In some embodiments, the manifold members <NUM> may be foam comprised of polyols such as polyester or polyether, isocyanate such as toluene diisocyanate, and polymerization modifiers such as amines and tin compounds. In some examples, the manifold members <NUM> may be reticulated polyurethane foam such as found in GRANUFOAM™ dressing or V. VERAFLO™ dressing, both available from Kinetic Concepts, Inc.

The thickness <NUM> of the manifold members <NUM> may vary according to needs of a prescribed therapy. For example, the thickness <NUM> of the manifold members <NUM> may be decreased to reduce tension on peripheral tissue. The thickness <NUM> of the manifold members <NUM> can also affect the conformability of the manifold members <NUM>. In some embodiments, the thickness <NUM> of the manifold members <NUM> may be between about <NUM> millimeters to about <NUM> millimeters. Further, in some embodiments, one or more of the manifold members <NUM> may have a three-dimensional size between about <NUM> cubic millimeters to about <NUM> cubic millimeters. Decreasing the size of the manifold members <NUM> may increase the resolution and conformability of the dressing <NUM> or the dressing filler <NUM>.

The manifold members <NUM> may be either hydrophobic or hydrophilic. In an example in which the manifold members <NUM> may be hydrophilic, the manifold members <NUM> may also wick fluid away from the tissue site <NUM>, while continuing to distribute negative pressure to the tissue site <NUM>. The wicking properties of the manifold members <NUM> may draw fluid away from the tissue site <NUM> by capillary flow or other wicking mechanisms. An example of a hydrophilic material that may be suitable is a polyvinyl alcohol, open-cell foam such as V. WHITEFOAM™ dressing available from Kinetic Concepts, Inc. Other hydrophilic foams may include those made from polyether. Other foams that may exhibit hydrophilic characteristics include hydrophobic foams that have been treated or coated to provide hydrophilicity.

In some embodiments, the manifold members <NUM> may be constructed from bioresorbable materials. Suitable bioresorbable materials may include, without limitation, a polymeric blend of polylactic acid (PLA) and polyglycolic acid (PGA). The polymeric blend may also include, without limitation, polycarbonates, polyfumarates, and capralactones.

Referring to <FIG>, the manifold members <NUM> may have the same shape or a different shape and may take many forms, sizes, 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 manifold members <NUM> may be adapted to the contours of deep and irregular shaped tissue sites. Any or all of the surfaces of the manifold members <NUM> may have an uneven, coarse, or jagged profile. In some embodiments, one or more of the manifold members <NUM> may be a manifold member 125a formed in the shape of a cube having a square cross-section as shown in <FIG>. In another embodiment, one or more of the manifold members <NUM> may be a manifold member 125b formed in the shape of a cylinder having a circular cross-section as shown in <FIG>. In another embodiment, one or more of the manifold members <NUM> may be a manifold member 125c having a triangular cross-section as shown in <FIG>. In another embodiment, one or more of the manifold members <NUM> may be a manifold member 125d formed in the shape of a cylinder and having an aperture disposed longitudinally through and between opposing surfaces of the cylinder as shown in <FIG>.

In addition to variations in the size and shape of each of the manifold members <NUM>, the manifold members <NUM> may be arranged or positioned relative to each other on the carrier <NUM> in a variety of patterns. In some embodiments, the manifold members <NUM>, 125a, 125b, 125c, 125d, or a manifold member of another shape, may be arranged in a matrix of rows and columns as shown in <FIG>, <FIG>, and <FIG>. In other embodiments, each of the manifold members <NUM> may be arranged to form different patterns or shapes to suit the anatomy of a particular tissue site. For example, the manifold members 125c having the triangular shape may be arranged in hexagonally shaped pattern as shown in <FIG>. Further, in other embodiments, different sizes of the manifold members 125b and 125d may be nested or arranged in a concentric circular pattern as shown in <FIG>.

Referring <FIG>, in some embodiments, the carrier <NUM> may include a plurality of fenestrations <NUM> disposed through the carrier <NUM>. The fenestrations <NUM> may be, for example, holes, apertures, slits, or perforations formed through the carrier <NUM> in any suitable manner. The fenestrations <NUM> may enhance fluid permeability through the carrier <NUM>. In some embodiments, the fenestrations <NUM> may be aligned or oriented lengthwise or longitudinally across the carrier <NUM> to form one or more separable perforations <NUM> on or through the carrier <NUM>. The separable perforations <NUM> may provide a sizing guide that may be separated, torn, or cut to size the carrier <NUM> and the dressing filler <NUM> for the tissue site <NUM>. For example, the separable perforations <NUM> may be positioned between the perimeter walls <NUM> or the exterior border <NUM> of the manifold members <NUM> to permit separation, tearing, or cutting to occur between the manifold members <NUM>. Such a configuration may reduce or eliminate the possibility of particulate contamination from occurring at the tissue site <NUM> from shavings, trimmings, or waste that may be created after the dressing filler <NUM> is sized.

In some embodiments, the fenestrations <NUM> and the separable perforations <NUM> may enhance or promote expansion or stretch of the carrier <NUM>. Herein, the fenestrations <NUM> may also be referred to as an expandable element <NUM>. In some embodiments, the carrier <NUM> may be formed from a non-stretchable material and the fenestrations <NUM> or the expandable element <NUM> may be configured to promote expansion of the non-stretchable material forming the carrier <NUM>. For example, the fenestrations <NUM> or the expandable element <NUM> may be configured to deform and to provide stretch or expansion when a tensile force <NUM> is applied to the carrier <NUM> as shown in <FIG>. Herein, a non-stretch material may be any material considered in the art to be rigid, resistant to stretch, or to have reduced elasticity compared to materials designed to have elastic properties, such as those described above for other embodiments of the carrier <NUM>.

In operation, the dressing filler <NUM> may be placed within, over, on, or otherwise proximate to a tissue site, such as the tissue site <NUM>. If the tissue site is a wound, for example, the dressing filler <NUM> may partially or completely fill the wound, or be placed over the wound. The sealing member <NUM> may be positioned over or covering the dressing filler <NUM> and sealed to an attachment surface near a tissue site. For example, the sealing member <NUM> may be sealed to undamaged epidermis peripheral to a tissue site.

A method is also described herein, wherein in some example embodiments a method for treating a tissue site may include providing the conformable dressing <NUM> comprising the plurality of discrete manifold members <NUM> coupled to the stretchable carrier <NUM>. The plurality of discrete manifold members <NUM> may be separated from one another along the exterior border <NUM>. Further, the method may include positioning the conformable dressing <NUM> into conformity with tissue at the tissue site <NUM>. At least a portion of the stretchable carrier <NUM> may be positioned in the stretched state, as shown, for example, in <FIG>, when the conformable dressing <NUM> is conformed to the tissue site <NUM>. Further, the method may include covering the conformable dressing <NUM> with the sealing member <NUM> to form the sealed space <NUM> at the tissue site <NUM>. Further, the method may include applying reduced pressure to the sealed space <NUM>.

One or more of the plurality of discrete manifold members <NUM> may be individually movable relative to one another when coupled to the stretchable carrier <NUM>. Further, the plurality of discrete manifold members <NUM> may be entirely separated from one another along the exterior border <NUM>. For example, in some embodiments, the plurality of discrete manifold members <NUM> may comprise detached blocks of porous material. Further, the plurality of discrete manifold members <NUM> may collapse into contact with one another as shown in <FIG> when a reduced pressure <NUM> is applied, thereby closing at least a portion of the separation distance <NUM> between the plurality of discrete manifold members <NUM>.

Further, the stretchable carrier <NUM> may be stretchable between the relaxed state and the stretched state. The separation distance <NUM> between the first exterior border 178a of one of the discrete manifold members <NUM> and the second exterior border 178b of another of the discrete manifold members <NUM> may be greater in the stretched state than the relaxed state.

Further, positioning the conformable dressing <NUM> may include tearing or cutting through the stretchable carrier <NUM> between the plurality of discrete manifold members <NUM> to size the conformable dressing <NUM> for the tissue site <NUM>. In some embodiments, positioning the conformable dressing <NUM> may include tearing or cutting through the separable perforations <NUM> in the stretchable carrier <NUM> to size the conformable dressing <NUM> for the tissue site <NUM>.

The systems, apparatuses, and methods described herein may provide significant advantages. The configuration of the manifold members <NUM> and the carrier <NUM> may enhance the ability of the dressing <NUM> and the dressing filler <NUM> to conform to the tissue site <NUM>, to contour to complex geometries, and to allow for articulation of limbs without causing pain, discomfort, or hindered healing. For example, the manifold members <NUM> are capable of moving independently with the carrier <NUM> as the carrier is stretched and conformed to the tissue site <NUM>. The conformability of the dressing <NUM> and the dressing filler <NUM> may accommodate tissues sites contoured or shaped in multiple directions, and may additionally reduce shearing forces across the tissue site <NUM>, prevent dislodgement of the dressing <NUM> and the dressing filler <NUM> from the tissue site <NUM>, and provide enhanced articulation and movement at the tissue site <NUM>.

Claim 1:
A system for treating a tissue site with reduced pressure, comprising a conformable dressing (<NUM>) comprising:
a plurality of discrete manifold members (<NUM>), each discrete manifold member (<NUM>) including a first surface (<NUM>) and a second surface (<NUM>), the first surface (<NUM>) separated from the second surface (<NUM>) by a perimeter wall (<NUM>); and
a carrier (<NUM>) including a first side (<NUM>) positioned facing the tissue site and a second side (<NUM>) positioned opposite the first side (<NUM>), wherein the carrier is expandable between a relaxed state and an expanded state, wherein a separation distance (<NUM>) between the perimeter wall (<NUM>) of a first of the plurality of discrete manifold members (<NUM>) and the perimeter wall (<NUM>) of a second of the plurality of discrete manifold members (<NUM>) is greater in the expanded state than in the relaxed state; and
an attachment device (<NUM>) comprising a plurality of separate points each
positioned between the first surface (<NUM>) of each of the discrete manifold members (<NUM>) and the second side (<NUM>) of the carrier (<NUM>), wherein the first surface (<NUM>) of each of the discrete manifold members (<NUM>) is coupled to the second side (<NUM>) of the carrier (<NUM>) by the attachment device (<NUM>);a sealing member (<NUM>) covering the conformable dressing (<NUM>) to create a sealed
space at the tissue site; and
a reduced pressure source (<NUM>) coupled in fluid communication with the sealed
space.