Negative Pressure Wound Therapy Canister

Abstract

A canister for use in a negative pressure wound therapy system includes a first fluid chamber, a second fluid chamber, and a filter disposed between the first and second fluid chambers. The first fluid chamber is configured to receive fluid from a tissue site. The filter is configured to filter fluid from the tissue site as it moves from the first fluid chamber to the second fluid chamber.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 413,872, filed October 6, 2022, which is incorporated herein by reference in its entirety.

[0002] The present invention as claimed herein relates generally to tissue treatment systems and more particularly, but not exclusively, to negative pressure wound therapy canisters. [Background technology]

[0003] Clinical studies and clinical practice have shown that reducing pressure near a tissue site can enhance and accelerate the growth of new tissue at that tissue site. While the applications of this phenomenon are numerous, it has proven particularly advantageous for treating wounds. Regardless of the etiology of the wound, whether traumatic, surgical, or otherwise, proper wound care is critical to the outcome. Treatment of wounds or other tissues using reduced pressure is sometimes commonly referred to as "negative pressure therapy," but is also known by other names, including, for example, "negative pressure wound therapy," "reduced pressure therapy," "vacuum therapy," "vacuum-assisted closure," and "topical negative pressure." Negative pressure therapy can provide several benefits, including epithelial and subcutaneous tissue migration, improved blood flow, and microdeformation of tissue at the wound site. Collectively, these benefits can enhance granulation tissue development and shorten healing time.

[0004] It is also widely accepted that cleansing a tissue site can be highly beneficial for new tissue growth. For example, a wound or cavity can be flushed with a liquid solution for therapeutic purposes. These clinical practices are commonly referred to as "irrigation" and "lavage," respectively. "Instillation" is another clinical practice that generally refers to the process of slowly introducing a fluid into a tissue site and leaving the fluid for a specified period of time before removing it. For example, instillation of a topical therapeutic solution onto a wound bed can be combined with negative pressure therapy to further promote wound healing by liberating soluble contaminants and removing infectious materials within the wound bed. This can result in a reduction in soluble bacterial load, removal of contaminants, and cleansing of the wound.

[0005] While the clinical benefits of negative pressure and / or infusion therapy are widely known, improvements in therapy systems, components, and processes can benefit healthcare providers and patients. Summary of the Invention

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

[0007] For example, in some embodiments, a canister for use in a negative pressure wound therapy system is described. The canister can include a first fluid chamber, a second fluid chamber, and a filter disposed between the first and second fluid chambers. The first fluid chamber can be configured to receive fluid from a tissue site. The filter can be configured to filter fluid from the tissue site as it moves from the first fluid chamber to the second fluid chamber.

[0008] In some exemplary embodiments, the filter can include a filter carrier, a primary filter, and a secondary filter. The filter carrier can be configured to be coupled to the canister between the first fluid chamber and the second fluid chamber. The primary filter can be coupled to the first filter carrier and positioned proximate to the second fluid chamber. The secondary filter can be coupled to the filter carrier and positioned proximate to the first fluid chamber.

[0009] In some exemplary embodiments, the canister may further include an instillation fluid path that may be configured to fluidly couple the second fluid chamber to the tissue site. In some exemplary embodiments, the instillation fluid path may be disposed along an exterior of the canister. In some exemplary embodiments, the instillation fluid path may be isolated from the first fluid chamber. In some exemplary embodiments, the canister may further include a negative pressure path. The negative pressure path may be configured to fluidly couple the first fluid chamber to the tissue site. In some exemplary embodiments, the negative pressure path may be isolated from the instillation fluid path. In some exemplary embodiments, the canister may further include a fill path. The fill path may be configured to fluidly couple the second fluid chamber to an external fluid source. In some exemplary embodiments, the fill path may be isolated from the negative pressure path and the instillation fluid path. In some exemplary embodiments, the canister may further include a sensor disposed in the instillation fluid path. The sensor may be configured to generate a signal representative of a fill status of the second fluid chamber.

[0010] In some exemplary embodiments, the canister can further include a first sterilization source and a second sterilization source. The first sterilization source can be configured to sterilize the first fluid chamber, and the second sterilization source can be configured to sterilize the second fluid chamber. In some exemplary embodiments, the first sterilization source and the second sterilization source are UV-C light emitting devices.

[0011] In some exemplary embodiments, the canister may further include a fluid change device disposed within the second fluid chamber. The fluid change device may be configured to release a chemical into the fluid disposed within the second fluid chamber. In some exemplary embodiments, the fluid change device may be configured to sterilize the fluid within the second fluid chamber. In some exemplary embodiments, the fluid change device may be configured to change a property of the fluid within the second fluid chamber.

[0012] In some exemplary embodiments, the canister can further include a negative pressure filter disposed within the first fluid chamber, the negative pressure filter can be configured to prevent liquid from the tissue site from contacting the negative pressure source.

[0013] In some exemplary embodiments, the second fluid chamber can include a port. In some exemplary embodiments, the port can be located at an end of the second fluid chamber opposite the first fluid chamber. In some exemplary embodiments, the canister can further include a plug configured to removably couple to the port. In some exemplary embodiments, the port can include a spout.

[0014] In some exemplary embodiments, the canister may further include a sensor disposed within the first fluid chamber, the sensor being configured to generate a signal representative of the fill state of the first fluid chamber.

[0015] Also described herein is a system for treating a tissue site. The system may include a dressing, a negative pressure source, and a canister. The dressing may be configured to be placed at the tissue site. The negative pressure source may be configured to be fluidly coupled to the dressing and further configured to generate negative pressure at the tissue site. The canister may be configured to be fluidly coupled between the dressing and the negative pressure source. The canister may include a first fluid chamber, a second fluid chamber, and a filter. The first fluid chamber may be configured to receive fluid from the tissue site, and the second fluid chamber may be configured to store fluid. The filter may be disposed between the first fluid chamber and the second fluid chamber. The filter may be configured to filter fluid from the tissue site as the fluid travels through the filter from the first fluid chamber to the second fluid chamber.

[0016] In some exemplary embodiments, the system can further include an instillation fluid pathway configured to fluidly couple the second fluid chamber to the tissue site. In some exemplary embodiments, the system can further include a negative pressure pathway configured to fluidly couple a negative pressure source to the dressing and the first fluid chamber of the canister. The negative pressure pathway can be isolated from the instillation fluid pathway.

[0017] Also described herein are methods for treating a tissue site. The method can include placing a dressing at the tissue site, fluidly coupling a negative pressure source to the dressing, and fluidly coupling a canister between the negative pressure source and the dressing. The canister can include a first fluid chamber, a second fluid chamber, and a filter. The first fluid chamber can be configured to collect fluid from the tissue site. The filter can be disposed between the first and second fluid chambers. The filter can be configured to filter fluid from the tissue site as it travels through the filter from the first fluid chamber to the second fluid chamber. The method can further include operating the negative pressure source to generate negative pressure in the dressing, drawing fluid from the tissue site into the first fluid chamber of the canister in response to the negative pressure, and filtering the fluid from the tissue site as it travels from the first fluid chamber to the second fluid chamber using the filter.

[0018] In some exemplary embodiments, the method can further include instilling the filtered fluid in the second fluid chamber into the tissue site.

[0019] In some exemplary embodiments, the method can further include discarding the filtered fluid from the second fluid chamber. In some exemplary embodiments, discarding the filtered fluid from the second fluid chamber can include removing a plug from an exhaust port of the second fluid chamber and drawing the filtered fluid from the second fluid chamber through the exhaust port.

[0020] In some exemplary embodiments, the method may further include purifying the fluid in the first fluid chamber using a UV-C source.

[0021] In some exemplary embodiments, the method may further include treating the filtered fluid in the second fluid chamber with a UV-C source.

[0022] In some exemplary embodiments, the second fluid chamber can be configured to receive and contain an instillation fluid.

[0023] In some exemplary embodiments, the method can further include filling the second fluid chamber with an infusion fluid. In some exemplary embodiments, the method can further include fluidly coupling the second fluid chamber to the dressing and infusing the infusion fluid from the second fluid chamber into the dressing. In some exemplary embodiments, filling the second fluid chamber with the infusion fluid can include adding the infusion fluid from an external fluid source through a port in the second fluid chamber. In some exemplary embodiments, filling the second fluid chamber with the infusion fluid can include coupling a fluid path of the canister to the external fluid source and operating a pump to draw fluid from the external fluid source into the second fluid chamber.

[0024] The objects, advantages and preferred modes of making and using the claimed subject matter can be best understood by referring to the accompanying drawings in conjunction with the following detailed description of exemplary embodiments. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a block diagram of an exemplary embodiment of a therapy system capable of providing negative pressure therapy and infusion therapy in accordance with the present disclosure. [Figure 2A] FIG. 2A is an exploded view of a recirculation canister that may be associated with some embodiments of FIG. 1, illustrating additional details that may be associated with some exemplary embodiments. [Figure 2B] FIG. 2B is a front view of the recirculation canister of FIG. 2A illustrating additional details that may be associated with some exemplary embodiments. [Figure 2C] FIG. 2C is a side view of the recirculation canister of FIG. 2A illustrating additional details that may be associated with some exemplary embodiments. [Figure 2D] FIG. 2D is a rear view of the recirculation canister of FIG. 2A illustrating additional details that may be associated with some exemplary embodiments. [Figure 2E] FIG. 2E is a cross-sectional view of the recirculation canister of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating additional details that may be associated with some exemplary embodiments. [Figure 3A] FIG. 3A is a cross-sectional view of the recirculation canister of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating the instillation mode of operation. [Figure 3B] FIG. 3B is a cross-sectional view of the recirculation canister of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating a negative pressure mode of operation. [Figure 3C] 3C is a cross-sectional view of the recirculation canister of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating fluid filtering from a first fluid chamber of the canister to a second fluid chamber of the canister. [Figure 3D] 3D is a cross-sectional view of the recirculation canister of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating the second fluid chamber of the canister containing liquid. [Figure 4A] FIG. 4A is an exploded view of a reusable canister that may be associated with some embodiments of FIG. 1, illustrating additional details that may be associated with some exemplary embodiments. [Figure 4B] FIG. 4B is a front view of the reusable canister of FIG. 4A illustrating additional details that may be associated with some exemplary embodiments. [Figure 4C] FIG. 4C is a rear view of the reusable canister of FIG. 4A illustrating additional details that may be associated with some exemplary embodiments. [Figure 4D] FIG. 4D is a side view of the reusable canister of FIG. 4A illustrating additional details that may be associated with some exemplary embodiments. [Figure 4E] FIG. 4E is a cross-sectional view of the reusable canister of FIG. 4A taken along line 4E-4E of FIG. 4C, illustrating additional details that may be associated with some exemplary embodiments. [Figure 4F] FIG. 4F is a cutaway view illustrating the second fluid chamber of the reusable canister of FIG. 4A, illustrating additional details that may be associated with some exemplary embodiments. [Figure 5A] FIG. 5A is a cross-sectional view of the reusable canister of FIG. 4A taken along line 4E-4E of FIG. 4C, illustrating a negative pressure mode of operation. [Figure 5B] 5B is a cross-sectional view of the reusable canister of FIG. 4A taken along line 4E-4E of FIG. 4C, illustrating fluid filtering from a first fluid chamber of the reusable canister to a second fluid chamber of the reusable canister. [Figure 5C] 5C is a cross-sectional view of the reusable canister of FIG. 4A taken along line 4E-4E of FIG. 4C, illustrating fluid being removed from the second fluid chamber of the reusable canister. [Figure 6A] FIG. 6A is a perspective view of another embodiment of the reusable canister of FIG. 1, illustrating additional details that may be associated with some exemplary embodiments. [Figure 6B] FIG. 6B is an exploded view of the reusable canister of FIG. 6A illustrating additional details that may be associated with some exemplary embodiments. [Figure 6C] FIG. 6C is a perspective view of another embodiment of the reusable canister of FIG. 1, illustrating additional details that may be associated with some exemplary embodiments. [Figure 6D] FIG. 6D is an exploded view of the reusable canister of FIG. 6C illustrating additional details that may be associated with some exemplary embodiments. [Figure 6E] FIG. 6E is a perspective view of another embodiment of the reusable canister of FIG. 1, illustrating additional details that may be associated with some exemplary embodiments. [Figure 6F] FIG. 6F is an exploded view of the reusable canister of FIG. 6E illustrating additional details that may be associated with some exemplary embodiments. [Figure 6G]FIG. 6G is a perspective view of another embodiment of the reusable canister of FIG. 1, illustrating additional details that may be associated with some exemplary embodiments. [Figure 6H] FIG. 6H is an exploded view of the reusable canister of FIG. 6G illustrating additional details that may be associated with some exemplary embodiments. [Figure 7] FIG. 7 is a cross-sectional side view of another embodiment of the recirculation canister of FIG. 1 illustrating additional details that may be associated with some exemplary embodiments. [Figure 8] FIG. 8 is a perspective view of one embodiment of a recirculating and reusable canister that may be associated with the therapy system of FIG. 1, illustrating additional details that may be associated with some exemplary embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0026] The following description of exemplary embodiments provides information to enable one skilled in the art to make and use the claimed subject matter, but may omit certain details that are already well known in the art. Therefore, the following detailed description is to be interpreted as illustrative and not limiting.

[0027] FIG. 1 is a block diagram of an exemplary embodiment of a therapy system 100 capable of providing negative pressure therapy using instillation of a topical therapeutic solution to a tissue site in accordance with the present disclosure.

[0028] 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, nerve tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendon, or ligament. Wounds can include, for example, chronic wounds, acute wounds, traumatic wounds, subacute wounds, and dehiscence wounds, partial-thickness burns, ulcers (such as diabetic ulcers, pressure ulcers, or venous insufficiency ulcers), skin flaps, and grafts. The term "tissue site" can also refer to any region of tissue that is not necessarily wounded or defective, but instead is an area where it may be desirable to add or promote the growth of additional tissue. For example, negative pressure can be applied to a tissue site to grow additional tissue, which can be harvested and transplanted.

[0029] Therapy system 100 may include a negative pressure source or supply, such as negative pressure source 105, and one or more distribution components. The distribution components are preferably separable and may be disposable, reusable, or recyclable. Dressings, such as dressing 110, and fluid containers, such as canister 115, are examples of distribution components that may be associated with some examples of therapy system 100. As shown in the example of FIG. 1, dressing 110, in some embodiments, may include or consist essentially of tissue interface 120, cover 125, or both.

[0030] A fluid conductor is another illustrative example of a distribution component. In this context, a "fluid conduit" broadly includes a tube, pipe, hose, conduit, or other structure having one or more lumens or open pathways adapted to transport fluid between two ends. Typically, a tube is an elongated, cylindrical structure with some flexibility, but the geometry and stiffness can vary. Furthermore, some fluid conductors can be molded into or otherwise integrally combined with other components. A distribution component can also include or configure an interface or fluid port to facilitate coupling and decoupling of other components. In some embodiments, for example, a dressing interface can facilitate coupling of the fluid conductor to the dressing 110. For example, such a dressing interface can be a SENSAT.RAC™ Pad available from Kinetic Concepts, Inc. (San Antonio, Texas).

[0031] Therapy system 100 may also include a controller, such as regulator or controller 130. Additionally, therapy system 100 may include sensors for measuring operating parameters and providing feedback signals indicative of those operating parameters to controller 130. As illustrated in FIG. 1 , for example, therapy system 100 may include first sensor 135 and second sensor 140 coupled to controller 130.

[0032] Therapy system 100 may also include an infusion solution source. For example, solution source 145 can be fluidly coupled to dressing 110, as shown in the exemplary embodiment of FIG. 1 . Solution source 145, in some embodiments, can be fluidly coupled to a positive pressure source, such as positive pressure source 150, a negative pressure source, such as negative pressure source 105, or both. A regulator, such as drip regulator 155, can also be fluidly coupled to solution source 145 and dressing 110 to ensure proper administration of infusion solution (e.g., saline) to the tissue site. For example, drip regulator 155 may comprise a piston that can be pneumatically actuated by negative pressure source 105 to draw infusion solution from the solution source during negative pressure intervals and to infuse the solution into the dressing during vent intervals. Additionally or alternatively, controller 130 can be coupled to negative pressure source 105, positive pressure source 150, or both to control the administration of infusion solution to the tissue site. In some embodiments, the drip regulator 155 can also be fluidly coupled to the negative pressure source 105 through the dressing 110, as shown in the example of FIG.

[0033] Some components of therapy system 100 may be housed within or used in conjunction with other components, such as sensors, processing units, alarm indicators, memory, databases, software, display devices, or user interfaces, that further facilitate therapy. For example, in some embodiments, negative pressure source 105 may be combined into therapy unit 160 along with controller 130, solution source 145, and other components.

[0034] In general, components of therapy system 100 may be directly or indirectly coupled. For example, negative pressure source 105 may be directly coupled to canister 115 or indirectly coupled to dressing 110 via canister 115. Coupling, in some contexts, may include fluid coupling, mechanical coupling, thermal coupling, electrical coupling, or chemical coupling (such as chemical bonding), or some combination of couplings. For example, negative pressure source 105 may be electrically coupled to controller 130 and fluidly coupled to one or more distribution components to provide a fluid pathway to the tissue site. In some embodiments, components may also be coupled by being physically close together, integrated into a single structure, or formed from the same piece of material.

[0035] A negative pressure source, such as negative pressure source 105, can be, for example, a reservoir of air at negative pressure, or can be a manually or electrically driven device, such as a vacuum pump, a suction pump, a wall suction port available in many medical facilities, or a micropump. "Negative pressure" generally refers to a pressure that is lower than the local ambient pressure, such as the ambient pressure in the local environment outside the sealed treatment environment. Often, the local ambient pressure can also be the atmospheric pressure where the tissue site is located. Alternatively, the pressure can be lower than the hydrostatic pressure associated with the tissue at the tissue site. Unless otherwise indicated, pressure values ​​described herein are gauge pressures. References to increased negative pressure typically refer to a decrease in absolute pressure, while a decrease in negative pressure typically refers to an increase in absolute pressure. The amount and nature of the negative pressure provided by the negative pressure source 105 can vary according to treatment requirements, but the pressure is generally a low vacuum, commonly referred to as a rough vacuum, between -5 mmHg (-667 Pa) and -500 mmHg (-66.7 kPa). A typical treatment range is between -50 mmHg (-6.7 kPa) and -300 mmHg (-39.9 kPa).

[0036] Canister 115 represents a container, canister, pouch, or other storage component that can be used to manage exudate and other fluids drawn from a tissue site. In many environments, a rigid canister may be preferred or required to collect, store, and discard fluids. In other environments, fluids can be properly discarded without storage in a rigid canister, and reusable canisters can reduce waste and costs associated with negative pressure therapy.

[0037] A controller, such as controller 130, may be a microprocessor or computer programmed to operate one or more components, such as negative pressure source 105, of therapy system 100. In some embodiments, for example, controller 130 may be a microcontroller, which generally comprises an integrated circuit including a processor core and memory, that is programmed to directly or indirectly control one or more operating parameters of therapy system 100. The operating parameters may include, for example, the power applied to negative pressure source 105, the pressure generated by negative pressure source 105, or the pressure delivered to tissue interface 120. Controller 130 is also preferably configured to receive one or more input signals, such as feedback signals, and is programmed to modify one or more operating parameters based on the input signals.

[0038] Sensors, such as first sensor 135 and second sensor 140, can be devices operable to detect or measure a physical phenomenon or characteristic and generally can provide a signal indicative of the detected or measured phenomenon or characteristic. For example, first sensor 135 and second sensor 140 can be configured to measure one or more operating parameters of therapy system 100. In some embodiments, first sensor 135 can be a transducer configured to measure the pressure in the pneumatic path and convert the measurement into a signal indicative of the measured pressure. In some embodiments, for example, first sensor 135 can be a piezoresistive strain gauge. In some embodiments, second sensor 140 can optionally measure an operating parameter of negative pressure source 105, such as voltage or current. Preferably, signals from first sensor 135 and second sensor 140 are suitable as input signals to controller 130, although in some embodiments, some signal conditioning may be appropriate. For example, the signals may need to be filtered or amplified before they can be processed by controller 130. Typically, the signal is an electrical signal, but may be expressed in other forms, such as an optical signal.

[0039] The tissue interface 120 can generally be adapted to partially or completely contact the tissue site. The tissue interface 120 can take many forms and can have many sizes, shapes, or thicknesses, depending on various factors, such as the type of treatment being performed or the nature and size of the tissue site. For example, the size and shape of the tissue interface 120 can be adapted to the contours of a deep, irregularly shaped tissue site. Any or all of the surfaces of the tissue interface 120 can have an undulating, rough, or jagged profile.

[0040] In some embodiments, tissue interface 120 may include or consist essentially of a manifold. A manifold in this context may include or consist essentially of a means for collecting or distributing fluid under pressure throughout tissue interface 120. For example, the manifold may be adapted to receive negative pressure from a source and distribute the negative pressure throughout tissue interface 120 via a plurality of openings, which may have the effect of collecting fluid throughout the 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 delivery of fluid, such as fluid from an instillation solution source, to a tissue site.

[0041] In some exemplary embodiments, the manifold may include multiple passages that can be interconnected to improve fluid distribution or collection. In some exemplary embodiments, the manifold may include or consist essentially of a porous material having interconnected fluid passages. Examples of suitable porous materials that can be adapted to form interconnected fluid passages (e.g., channels) include cellular foams, including open-cell foams such as reticulated foams; porous tissue aggregates; and other porous materials, such as gauze or felted mats, that generally include pores, edges, and / or walls. Liquids, gels, and other foams may also include or be hardened to include openings and fluid passages. In some embodiments, the manifold may additionally or alternatively include protrusions that form the interconnected fluid passages. For example, the manifold may be molded to provide surface protrusions that define the interconnected fluid passages.

[0042] In some embodiments, the tissue interface 120 may include or consist essentially of a reticulated foam with pore size and porosity that can vary according to the needs of the prescribed therapy. For example, a reticulated foam with a porosity of at least 90% may be suitable for many therapeutic applications, and a foam with an average pore size in the range of 400-600 microns (40-50 pores per inch) may be particularly suitable for some types of therapy. The tensile strength of the tissue interface 120 may also vary according to the needs of the prescribed therapy. For example, the tensile strength of the foam may be increased for instillation of a topical therapeutic solution. The 25% compressive load deflection of the tissue interface 120 may be at least 0.35 pounds per square inch, and the 65% compressive load deflection may be at least 0.43 pounds per square inch. In some embodiments, the tensile strength of the tissue interface 120 may be at least 10 pounds per square inch. The tissue interface 120 may have a tear strength of at least 2.5 pounds per square inch. In some embodiments, the tissue interface can be a foam composed of a polyol, such as a polyester or polyether, an isocyanate, such as toluene diisocyanate, and a polymerization modifier, such as an amine and tin compound. In some examples, the tissue interface 120 can be a reticulated polyurethane foam, such as found in GRANUFOAM™ dressings or VACVERAFLO™ dressings, both available from Kinetic Concepts, Inc. (San Antonio, Texas).

[0043] The thickness of the tissue interface 120 may also vary according to the needs of the prescribed therapy. For example, the thickness of the tissue interface may be reduced to reduce tension on the surrounding tissue. The thickness of the tissue interface 120 may also affect the conformability of the tissue interface 120. In some embodiments, a thickness in the range of approximately 5 millimeters to 10 millimeters may be suitable.

[0044] The tissue interface 120 can be either hydrophobic or hydrophilic. In one embodiment in which the tissue interface 120 may be hydrophilic, the tissue interface 120 can also wick fluid away from the tissue site while continuing to distribute negative pressure to the tissue site. The wicking properties of the tissue interface 120 can draw fluid away from the tissue site by capillary flow or other wicking mechanisms. One example of a hydrophilic material that may be suitable is an open-cell foam of polyvinyl alcohol, such as VACWHITEFOAM™ dressing available from Kinetic Concepts, Inc. (San Antonio, Texas). Other hydrophilic foams may include those made from polyethers. Other foams that may exhibit hydrophilic properties include hydrophobic foams that have been treated or coated to provide hydrophilic properties.

[0045] In some embodiments, the tissue interface 120 can be constructed from a bioabsorbable material. Suitable bioabsorbable materials include, but are not limited to, polymer blends of polylactic acid (PLA) and polyglycolic acid (PGA). Polymer blends can also include, but are not limited to, polycarbonate, polyfumarate, and capralactone. The tissue interface 120 can also serve as a scaffold for new cell growth, or a scaffold material can be used in conjunction with the tissue interface 120 to promote cell growth. A scaffold is generally a substance or structure used to enhance or promote cell growth or tissue formation, such as a three-dimensional porous structure that provides a template for cell growth. Illustrative examples of scaffold materials include calcium phosphate, collagen, PLA / PGA, coral hydroxyapatite, carbonate, or processed allograft materials.

[0046] In some embodiments, cover 125 can provide a bacterial barrier and protection from physical trauma. Cover 125 can also be constructed from a material capable of reducing evaporative loss and providing a fluid seal between two components or two environments, such as between a treatment environment and a local external environment. Cover 125 can include or consist, for example, of an elastic film or membrane capable of providing a seal sufficient to maintain negative pressure at the tissue site for a given negative pressure source.

[0047] In some exemplary embodiments, the cover 125 can be a polymer drape, such as a polyurethane film, that is permeable to water vapor but impermeable to liquids. In other embodiments, the cover 125 can be impermeable to both water vapor and liquids. Such drapes typically have a thickness in the range of 25 to 50 microns. For permeable materials, their permeability should generally be low enough to maintain the desired negative pressure. The cover 125 can include, for example, one or more of polyurethanes (PU), such as hydrophilic polyurethanes; cellulosic materials; hydrophilic polyamides; polyvinyl alcohols; polyvinylpyrrolidones; hydrophilic acrylics; silicones, such as hydrophilic silicone elastomers; natural rubber; polyisoprene; styrene butadiene rubber; chloroprene rubber; polybutadiene; nitrile rubber; butyl rubber; ethylene propylene rubber; ethylene propylene diene monomer; chlorosulfonated polyethylene; polysulfide rubber; ethylene vinyl acetate (EVA); copolyesters; and polyether block polyamide copolymers. Such materials are commercially available, for example, as Tegaderm® drapes available from 3M Company (Minneapolis, Minnesota), polyurethane (PU) drapes available from Avery Dennison Corporation (Pasadena, California), polyether block polyamide copolymer (PEBAX) available from Arkema SA (Colombes, France), and INSPIRE® 2301 and INSPIRE® 2327 polyurethane films available from Exopack Advanced Coatings (Wrexham, United Kingdom). In some embodiments, the cover 125 is 2600 g / m 2 / 24 hour MVTR (Upright Cup Technology) and INSPIRE® 2301 having a thickness of approximately 30 microns.

[0048] An attachment device can be used to attach the cover 125 to an attachment surface, such as an intact epidermis, a gasket, or another cover. The attachment device can take many forms. For example, the attachment device can be a medically acceptable pressure-sensitive adhesive configured to bond the cover 125 to the epidermis surrounding the tissue site. In some embodiments, for example, part or all of the cover 125 can be coated with an adhesive, such as an acrylic adhesive, which can have a coating weight of approximately 25 to 65 grams per square meter (gsm). In some embodiments, a thicker adhesive or combination of adhesives can be applied to improve the seal and reduce leakage. Other exemplary embodiments of attachment devices can include double-sided tape, paste, hydrocolloid, hydrogel, silicone gel, or organogel.

[0049] Solution source 145 may also represent a container, canister, pouch, bag, or other storage component capable of providing a solution for infusion therapy. While the composition of the solution may vary according to the prescribed therapy, examples of solutions that may be suitable for some formulations include hypochlorite-based solutions, silver nitrate (0.5%), sulfur-based solutions, biguanides, cationic solutions, and isotonic solutions.

[0050] During operation, tissue interface 120 may be placed within, over, on, or otherwise adjacent to a tissue site. For example, if the tissue site is a wound, tissue interface 120 may partially or completely occlude or be placed over the wound. Cover 125 may be placed over tissue interface 120 and sealed to an attachment surface near the tissue site. For example, cover 125 may be sealed to intact epidermis around the tissue site. Thus, dressing 110 can provide a sealed treatment environment adjacent to the tissue site that is substantially isolated from the external environment, and negative pressure source 105 can reduce pressure within the sealed treatment environment.

[0051] The process of reducing pressure may be illustratively described herein as, for example, "delivering," "distributing," or "generating" negative pressure. Generally, exudates and other fluids flow along a fluid pathway toward lower pressure. Thus, the term "downstream" typically refers to a location within a fluid pathway that is relatively closer to a source of negative pressure or farther away from a source of positive pressure. Conversely, the term "upstream" refers to a location relatively farther away from a source of negative pressure or nearer to a source of positive pressure.

[0052] In a sealed treatment environment, negative pressure applied across the tissue site via tissue interface 120 can induce macro- and micro-strains at the tissue site. The negative pressure can also remove exudate and other fluids from the tissue site, which can collect in canister 115.

[0053] In some embodiments, the controller 130 may receive and process data from one or more sensors, such as the first sensor 135. The controller 130 may also control the operation of one or more components of the therapy system 100 to manage the pressure delivered to the tissue interface 120. In some embodiments, the controller 130 may include an input for receiving a desired target pressure and may be programmed to process data regarding the setting and input of the target pressure to be applied to the tissue interface 120. In some exemplary embodiments, the target pressure may be a fixed pressure value set by an operator as the desired target negative pressure for therapy at the tissue site and then provided as an input to the controller 130. The target pressure may vary from tissue site to tissue site based on the type of tissue forming the tissue site, the type of injury or wound (if present), the patient's medical condition, and the attending physician's preferences. After selecting the desired target pressure, the controller 130 may operate the negative pressure source 105 in one or more control modes based on the target pressure and may receive feedback from one or more sensors to maintain the target pressure at the tissue interface 120.

[0054] In some embodiments, the controller 130 can have a continuous pressure mode in which the negative pressure source 105 is operated to provide a constant target negative pressure for the duration of the treatment or until manually deactivated. Additionally, or alternatively, the controller can have an intermittent pressure mode. In some exemplary embodiments, the controller 130 can operate the negative pressure source 105 to cycle between the target pressure and atmospheric pressure. For example, the target pressure may be set to a value of 135 mmHg for a specified period of time (e.g., 5 minutes), followed by a specified period of time of rest (e.g., 2 minutes). This cycle can be repeated by activating the negative pressure source 105, thereby creating a square wave pattern between the target pressure and atmospheric pressure.

[0055] In some exemplary embodiments, the increase in negative pressure from ambient pressure to the target pressure may not be instantaneous. For example, the negative pressure source 105 and the dressing 110 may have an initial rise time. The initial rise time may vary depending on the type of dressing and treatment device being used. For example, the initial rise time for one therapy system may be in the range of approximately 20-30 mmHg / sec, while for another therapy system it may be in the range of approximately 5-10 mmHg / sec. If the therapy system 100 is operating in an intermittent mode, the recurring rise time may be substantially equal to the initial rise time.

[0056] In some exemplary dynamic pressure control modes, the target pressure can vary over time. For example, the target pressure can vary in the form of a triangular waveform that varies between 50 and 135 mmHg of negative pressure with a negative pressure rise rate set at a rate of +25 mmHg / min and a fall rate set at -25 mmHg / min. In other embodiments of therapy system 100, the triangular waveform can vary between 25 and 135 mmHg of negative pressure with a rise and fall rate of approximately +30 mmHg / min or approximately -30 mmHg / min.

[0057] In some embodiments, the controller 130 can control or determine a variable target pressure in a dynamic pressure mode, which can vary between a maximum and minimum pressure value that can be set as an operator-defined input as a range of desired negative pressure. The variable target pressure can also be processed and controlled by the controller 130, which can vary the target pressure according to a predetermined waveform, such as a triangular waveform, a sinusoidal waveform, or a sawtooth waveform. In some embodiments, the waveform can be set by the operator as a predetermined or time-varying negative pressure desired for treatment.

[0058] In some embodiments, controller 130 can receive and process data, such as data related to the infusion solution provided to tissue interface 120. Such data can include the type of infusion solution prescribed by the clinician, the volume of fluid or solution to be infused at the tissue site (the “fill volume”), and the amount of time (the “dwell time”) the solution is allowed to sit at the tissue site before applying negative pressure to the tissue site. The fill volume can be, for example, 10 to 500 mL, and the dwell time can be 1 second to 30 minutes. Controller 130 can also control the operation of one or more components of therapy system 100 to infuse the solution. For example, controller 130 can manage the fluid dispensed from solution source 145 to tissue interface 120. In some embodiments, the fluid can be infused at the tissue site by applying negative pressure from negative pressure source 105 to reduce pressure at the tissue site and draw the solution into tissue interface 120. In some embodiments, the solution can be instilled into the tissue site by applying positive pressure from a positive pressure source 150 to move the solution from the solution source 145 to the tissue interface 120. Additionally or alternatively, the solution source 145 may be elevated to a height sufficient to allow gravity to move the solution to the tissue interface 120.

[0059] The controller 130 can also control the fluid dynamics of the infusion by providing a continuous flow of solution or an intermittent flow of solution. Negative pressure can be applied to provide either a continuous or intermittent flow of solution. The application of negative pressure can be implemented to provide a continuous pressure mode of operation to achieve a continuous flow rate of infused solution through the tissue interface 120, or a dynamic pressure mode of operation to vary the flow rate of infused solution through the tissue interface 120. Alternatively, the application of negative pressure can be implemented to provide an intermittent mode of operation to allow infused solution to dwell at the tissue interface 120. In the intermittent mode, a particular fill volume and dwell time can be provided, depending, for example, on the type of tissue site being treated and the type of dressing being utilized. Negative pressure therapy can be applied after or during the infusion of solution. The controller 130 can be utilized to select the operating mode and duration of negative pressure therapy before initiating another infusion cycle by infusing more solution.

[0060] Negative pressure therapy and infusion therapy may increasingly be performed in home environments across more geographic areas. Many current canisters and infusion fluid sources for therapy systems are single-use devices intended for use in hospital or clinic settings. When the devices approach the end of their useful life, the canisters and infusion fluid sources can be removed from the therapy system and replaced. Removal and replacement of canisters and infusion fluid sources from a therapy system can involve complex fluid connections, which can be best handled by a trained clinician. In a home environment, it may be difficult for a patient to handle the removal and replacement of canisters and infusion fluid sources necessary to fully treat a tissue site. Some systems require interaction with many different devices, which can be cumbersome. In a home environment, some patients may be concerned about the environmental impact of discarding these devices during treatment of a tissue site. The canister 115 may address these and other issues by providing a reusable and / or recirculating system that can contain both wound exudate and infusion fluid. In some embodiments, the canister 115 may be capable of filtering and / or purifying the exudate to produce a fluid suitable for disposal down a drain or suitable for reusing the purified fluid to cleanse a tissue site.

[0061] 2A-2E show various views of an exemplary embodiment of canister 115 of therapy system 100 of FIG. 1. In some embodiments, canister 115 may be a recirculating canister. FIG. 2B is a front view of canister 115. FIG. 2C is a side view of canister 115. FIG. 2D is a rear view of canister 115. FIG. 2E is a cross-sectional view of canister 115 taken along line 2E-2E of FIG. 2D.

[0062] 2A is an exploded view of canister 115 illustrating additional details that may be associated with some embodiments. Canister 115 may include a canister body 202, a canister plate 204, a filter 206, one or more negative pressure filters 208, and an infusion system 210. Canister body 202 may at least partially define interior 230. In some embodiments, canister body 202 may have a stadium or oval shape. In other embodiments, canister body 202 may have other shapes that include interior 230. Interior 230 may be configured to receive and retain fluid within canister 115 after assembly of canister 115.

[0063] In some embodiments, the canister body 202 may include a first wall 218 and a second wall 220. The second wall 220 may be semi-oval in shape. The first wall 218 may be an annular wall having an oval shape and may have a first end coupled to an edge 221 of the second wall 220 formed by a surface that creates the semi-oval shape of the second wall 220. In some embodiments, the second end of the first wall 218 may form an opening 219 to the interior 230 of the canister body 202. The second end of the first wall 218 may be configured to receive the canister plate 204. The canister body 202 may include a first end 214 and a second end 216 opposite the first end 214. The first end 214 may be the upper end or top surface of the canister body 202, and the second end 216 may be the lower end or bottom surface of the canister body 202. The canister body 202 may have a first side 222 and a second side 224 extending between the first end 214 and the second end 216. The first side 222 and the second side 224 may oppose each other and form part of the exterior surface of the canister body 202. In some embodiments, the first side 222 and the second side 224 may be generally symmetrical to each other. The first side 222 and the second side 224 may have variations in symmetry to accommodate other elements of the canister 115.

[0064] In some embodiments, the first wall 218 of the canister body 202 may include a joining edge 226. For example, the joining edge 226 may be a second end of the first wall 218 opposite the second wall 220. The joining edge 226 may be configured to be joined to the canister plate 204 to close the interior 230.

[0065] The canister body 202 may also include one or more connectors, such as a first connector 228, a second connector 229, and a third connector 231. In some embodiments, the first connector 228 may be disposed on the first side 222 of the canister body 202, and the second connector 229 may be disposed on the second side 224 of the canister body 202. The first connector 228 and the second connector 229 may be coupled to the first wall 218 of the canister body 202. In some embodiments, the first connector 228 and the second connector 229 may be aligned with one another between the first end 214 and the second end 216. For example, the first connector 228 may be positioned approximately midway between the first end 214 and the second end 216. Similarly, the second connector 229 may be positioned approximately midway between the first end 214 and the second end 216. In some embodiments, first connector 228 and second connector 229 may be disposed within a recess formed in an outer surface of first wall 218. Third connector 231 may be coupled to second end 216 of canister body 202. Third connector 231 may be positioned in the center of second end 216 between first side 222 and second side 224. First connector 228, second connector 229, and third connector 231 may comprise releasable latches that allow canister 115 to be coupled to and decoupled from therapy system 100. In some embodiments, first connector 228, second connector 229, and third connector 231 may be part of a cantilever snap-fit ​​type latch configured to be inserted into a receptacle of therapy system 100.

[0066] The canister body 202 may include features within the interior 230 of the canister body 202 to provide structure for elements such as the filter 206. For example, the canister body 202 may include a channel 233 formed by a first shelf 232 and a second shelf 234. The first shelf 232 and the second shelf 234 may be coupled to the first wall 218 and the second wall 220 on surfaces of the first wall 218 and the second wall 220 that face the interior 230. In some embodiments, the first shelf 232 and the second shelf 234 extend from the first side 222 of the canister body 202 to the second side 224 of the canister body 202. The first shelf 232 and the second shelf 234 may be generally parallel to one another such that the width of the channel 233 is substantially constant. The filter 206 may be disposed within the channel 233 and may divide the canister 115 into a first fluid chamber 282 and a second fluid chamber 284. The first fluid chamber 282 may be configured to receive fluid from the tissue site and may be disposed between the filter 206 and the first end 214 of the canister body 202. The second fluid chamber 284 may be disposed between the filter 206 and the second end 216 of the canister body 202.

[0067] The canister body 202 may additionally include at least one communication element. In some embodiments, the at least one communication element may be a fluid inlet 236 disposed at or proximate the first end 214 of the canister body 202. The fluid inlet 236 may be a port having at least one channel or lumen therein to allow fluid to flow between the external environment and the interior 230 across one or more of the first wall 218 and the second wall 220. In some embodiments, the fluid inlet 236 may be disposed in a recess formed in the exterior of the first wall 218 proximate the first end 214. The at least one communication element may also include a fluid outlet 238. The fluid outlet 238 may be a port having at least one channel or lumen therein to allow fluid to flow from the interior 230 of the canister body 202 to the external environment across one or more of the first wall 218 and the second wall 220. In some embodiments, the canister body 202 may additionally include a sensing line 240. The sensing line 240 may comprise a channel, lumen, or other fluid pathway from the therapy unit 160 through the canister 115 to enable the therapy unit 160 to sense pressure in the dressing 110.

[0068] In some embodiments, the canister body 202 may optionally include a fluid change device 241. The fluid change device 241 may be disposed within the second fluid chamber 284. The fluid change device 241 may be configured to change the properties of the fluid within the second fluid chamber 284. For example, in some embodiments, the fluid change device 241 may be configured to sterilize the fluid within the second fluid chamber 284. Additionally or alternatively, the fluid change device 241 may be configured to generate a saline solution from the fluid stored within the second fluid chamber 284. In some embodiments, the fluid change device 241 may be configured to change the properties of the fluid based on what is beneficial to the tissue site being treated by the therapy system 100.

[0069] In some embodiments, canister body 202 may optionally include a first sensor 243. First sensor 243 may be disposed within first fluid chamber 282. In some embodiments, first sensor 243 may be configured to generate a signal indicative of the fluid level within first fluid chamber 282. In some embodiments, first sensor 243 may be communicatively coupled to at least controller 130 of therapy system 100 such that controller 130 may receive the signal indicative of the fluid level within first fluid chamber 282 and operate other components of therapy system 100 in response.

[0070] The canister plate 204 may be stadium-shaped, oval-shaped, or another shape that aligns with the joining edge 226 of the first wall 218 of the canister body 202. The canister plate 204 may have a first end 242 and a second end 244 opposite the first end 242. The canister plate 204 may include a first side 246 extending from the first end 242 to the second end 244 and a second side 248 opposite the first side 246. The canister plate 204 may have a first recess 250 in the first side 246 and a second recess 252 in the second side 248. Both the first recess 250 and the second recess 252 may be aligned with recesses in the first wall portion 218 in which the first connector 228 and the second connector 229 of the canister body 202 are disposed.

[0071] The canister plate 204 may additionally include an outer surface 254 and an inner surface 256 opposite the outer surface 254. The outer surface 254 of the canister plate 204 may include a channel 258 that may be configured to receive one or more components of the infusion system 210. The channel 258 may have a first end 260 and a second end 262 opposite the first end 260. The first end 260 may include a first opening 264, and the second end 262 may include a second opening 266. In some embodiments, the canister plate 204 may be coupled to the coupling edge 226 of the first wall 218, and the second opening 266 may be aligned with the fluid outlet 238 of the canister body 202.

[0072] The canister plate 204 may also include a pressure sensor opening 268 and a negative pressure opening 270. The pressure sensor opening 268 and the negative pressure opening 270 may each be located proximate the first end 242 of the canister plate 204. In some embodiments, the pressure sensor opening 268 may be located centrally between the first side 246 and the second side 248, and between the channel 258 and the first end 242 of the canister plate 204. The negative pressure opening 270 may be located between the pressure sensor opening 268 and the first side 246. In some embodiments, the canister plate 204 may be coupled to the coupling edge 226 of the first wall 218, the pressure sensor opening 268 may be fluidly coupled to the sensing line 240, and the negative pressure opening 270 may be fluidly coupled to the interior 230 of the canister body 202.

[0073] In some embodiments, the canister plate 204 may optionally include one or more sterilization sources, such as a first sterilization source 294 and a second sterilization source 296. In some embodiments, the first sterilization source 294 may be located proximate to the first fluid chamber 282, and the second sterilization source 296 may be located proximate to the second fluid chamber 284. The one or more sterilization sources may be configured to sterilize the first fluid chamber 282 and the second fluid chamber 284. For example, the one or more sterilization sources may be configured to sterilize, reduce, or eliminate any bacteria, mold, viruses, or other potentially harmful contaminants located within the canister 115. In some embodiments, the one or more sterilization sources may be diodes, such as UV-C light-emitting diodes. In some embodiments, the UV-C light-emitting diodes may emit electromagnetic radiation in a wavelength range of about 100 nanometers to about 280 nanometers.

[0074] In some embodiments, the exterior surface 254 of the canister plate 204 may be configured to mate with the therapy unit 160. In some embodiments, the first sterilization source 294 and the second sterilization source 296 may be windows that extend through the canister plate 204. The therapy unit 160 may include one or more sterilization sources, such as UV-C light emitting diodes, that may be configured to align with windows that extend through the canister plate 204. The windows may be configured to transmit electromagnetic radiation from the one or more sterilization source light emitting diodes to the interior 230 of the canister body 202. In some embodiments, there may be one sterilization source that may be configured to transmit electromagnetic radiation through each of the windows in the canister plate 204. Alternatively, there may be two or more sterilization sources.

[0075] One or more sterilization sources may be communicatively coupled to the controller 130 of the therapy unit 160. The one or more sterilization sources may be configured to be activated to sterilize the interior 230 of the canister body 202. In some embodiments, the first sterilization source 294 may be configured to sterilize the first fluid chamber 282, and the second sterilization source 296 may be configured to sterilize the second fluid chamber 284.

[0076] Infusion system 210 may include an inlet 272, an outlet 274, and a conduit 276. Inlet 272 may couple conduit 276 to first opening 264. In some embodiments, inlet 272 may provide a fluid pathway from a lumen 281 of conduit 276 to first opening 264. Inlet 272 may include a first part 271 and a second part 273. First part 271 may be a grommet or other seal configured to couple inlet 272 to first opening 264 while maintaining a fluid seal between the fluid passage through inlet 272 and first opening 264. Second part 273 may be an elbow connector or other device configured to receive fluid flowing in a first direction and direct the fluid in a second direction. There may be a first lumen 283 extending through first part 271 and a second lumen 285 extending through second part 273. First lumen 283 and second lumen 285 may provide a path for fluid to travel through first component 271 and second component 273 .

[0077] The outlet 274 may couple the conduit 276 to the second opening 266. In some embodiments, the outlet 274 may provide a fluid pathway from the lumen of the conduit 276 to the second opening 266. The outlet 274 may include a first part 275 and a second part 277. The first part 275 may be a grommet or other seal configured to couple the outlet 274 to the second opening 266 while maintaining a fluid seal between the fluid passage through the outlet 274 and the second opening 266. The second part 277 may be an elbow connector or other device configured to receive fluid flowing in a first direction and direct the fluid in a second direction. There may be a first lumen 287 extending through the first part 275 and a second lumen 289 extending through the second part 277. First lumen 287 and second lumen 289 may provide a path for fluid to travel through first component 275 and second component 277 .

[0078] In some embodiments, infusion system 210 may further include a second sensor 279. Second sensor 279 may be configured to generate a signal representative of the fill status of second fluid chamber 284. For example, second sensor 279 may be configured to sense when second fluid chamber 284 is empty. In some embodiments, second sensor 279 may be communicatively coupled to at least controller 130 of therapy system 100 such that if controller 130 receives a signal from second sensor 279 indicating that second fluid chamber 284 is empty, controller 130 may terminate infusion therapy of therapy system 100.

[0079] In some embodiments, infusion system 210 may additionally include one or more valves. The valves may be one-way valves and may be positioned within infusion system 210 to prevent fluid from passing through infusion system 210 and into canister 115. In some embodiments, components of infusion system 210 may be formed from plastics, polymers, thermoplastics, metals, metal alloys, composite materials, fibrous materials, and other similar materials.

[0080] In some embodiments, the one or more negative pressure filters 208 may include a first filter 278 and a second filter 280. The first filter 278 may be configured to be positioned adjacent the inner surface 256 of the canister plate 204 to cover the pressure sensor opening 268. The second filter 280 may be configured to be positioned adjacent the inner surface 256 of the canister plate 204 to cover the negative pressure opening 270. The first filter 278 may be a liquid-gas separator and may be configured to prevent liquids and exudates from the interior 230 of the canister body 202 from exiting the canister 115 through the pressure sensor opening 268. The second filter 280 may be a liquid-gas separator and may be configured to prevent liquids and exudates from the interior 230 of the canister body 202 from exiting the canister 115 through the negative pressure opening 270.

[0081] In some embodiments, filter 206 may be positioned within channel 233 and held in place between first shelf 232 and second shelf 234. In some embodiments, filter 206 may be supported by first shelf 232 and second shelf 234 of canister body 202. Filter 206 may include a filter carrier 286, a primary filter 288, and a secondary filter 290. Filter carrier 286 may be disposed between primary filter 288 and secondary filter 290 and may be configured to provide support to one or both of primary filter 288 and secondary filter 290. Primary filter 288 may be coupled to filter carrier 286 and disposed proximate second fluid chamber 284. Secondary filter 290 may be proximate or coupled to filter carrier 286 and disposed proximate first fluid chamber 282. In some embodiments, the secondary filter 290 may be configured to be mounted on the first shelf 232 and the filter carrier 286, and the primary filter 288 may be positioned between the first shelf 232 and the second shelf 234.

[0082] Filter 206 may be configured to filter fluid from the tissue site as it moves from first fluid chamber 282 to second fluid chamber 284. In some embodiments, filter 206 may include a material capable of physically filtering fluid such that water (H2O) molecules may pass through filter 206 while larger bacterial molecules are captured by filter 206. Additionally, one or more of filter carrier 286, primary filter 288, or secondary filter 290 of filter 206 may be positively or negatively charged to capture bacteria while allowing plasma to pass through filter 206.

[0083] The infusion system 210 may be configured to fluidly couple the second fluid chamber 284 to the dressing 110. More specifically, fluid within the second fluid chamber 284 may be transported from the second fluid chamber 284, through the infusion system 210, through the fluid outlet 238, and to the dressing 110 at the tissue site. The infusion system 210 may be configured to transport the fluid in the second fluid chamber 284 to the dressing 110 while remaining fluidly isolated from the first fluid chamber 282.

[0084] In some embodiments, canister 115 may be manufactured to be received by a user or medical professional with instillation fluid in second fluid chamber 284. Additionally, or alternatively, canister 115 may be received by a user or medical professional without fluid in second fluid chamber 284. Instillation fluid may be introduced into second fluid chamber 284 before using canister 115 to treat a tissue site. In some embodiments, canister 115 may be coupled to an external fluid source before using canister 115 and therapy system 100 to treat a tissue site. More specifically, the external fluid source may be coupled to instillation system 210 by a tube, conduit, or another element. Controller 130 may be configured to operate positive pressure source 150 in reverse such that instillation fluid stored in the external fluid source may be drawn from the external fluid source into second fluid chamber 284 of canister 115. For example, fluid may flow from an external fluid source through a tube or conduit to reach fluid outlet 238. From fluid outlet 238, fluid may flow through first and second parts 275 and 277 of outlet 274, through conduit 276, through second and first parts 273 and 271 of inlet 272 to reach second fluid chamber 284. Once infusion fluid is stored in second fluid chamber 284, therapy system 100 may be able to infuse the infusion fluid from second fluid chamber 284 into dressing 110.

[0085] In some embodiments, the instilled fluid may not be introduced into the canister 115 before operating the therapy system 100 to treat the tissue site. Therapy system 100 may operate to draw the dressing 110 to a desired negative pressure, thereby drawing fluid from the dressing 110 into the first fluid chamber 282 of the canister 115. The fluid may be filtered through the filter 206, as described above, so that the purified or filtered fluid may be stored in the second fluid chamber 284. Once a predetermined amount of fluid has been stored in the second fluid chamber 284, therapy system 100 may be enabled to instill the fluid from the second fluid chamber 284 into the dressing 110.

[0086] In some embodiments, canister 115 may further include a communication element that may be communicatively coupled to therapy unit 160 of therapy system 100. In some embodiments, the communication element may utilize RFID technology, which may allow therapy system 100 to be used only with a particular patient and / or therapy unit. For example, the communication element may be configured to track one or more devices and / or patients with which canister 115 has been used and keep a record of the patient and the lifespan of canister 115. This information may be configured to be stored in a database that may be accessible by a healthcare provider. The communication element of canister 115 may also track the number of dressings to which canister 115 is coupled. In some embodiments, that data may be used to optimize the performance of canister 115.

[0087] In some embodiments, the canister body 202 and the canister plate 204 may be transparent. In other embodiments not shown herein, the canister body 202 and / or the canister plate 204 may be partially transparent, partially opaque, or both. The canister body 202 and the canister plate 204 may be formed from plastics, polymers, thermoplastics, metals, metal alloys, composites, fibrous materials, and other similar materials. Plastics, as described herein, are substances or structures that can be molded or shaped with or without the application of heat and may be typically synthetic polymers combined with other ingredients such as hardeners, fillers, reinforcing agents, and plasticizers. Plastics can be formed or molded under heat and pressure in their green state and machined, trimmed, and finished with high dimensional accuracy in their hardened state. Thermoplastic types can be re-softened to their original state by heat. Additionally, plastic may refer to engineering plastics, such as plastics that can withstand high levels of stress, are machinable, and are dimensionally stable. Some exemplary plastics are nylon, acetyl, polycarbonate, ABS, PPO / styrene, ISOPLAST 2530, TURLUX HS 2822, and polybutylene terephthalate. The thermoplastics described herein may be polymers that soften when exposed to heat and return to their original state when cooled to room temperature.

[0088] 3A is a cross-sectional view of the recirculation canister 115 of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating the instillation mode of operation. In FIG. 3A, fluid 302 is transported from the second fluid chamber 284 through the first lumen 283 of the first part 271, the second lumen 285 of the second part 273, the lumen 281 of the conduit 276, the first lumen 287 of the first part 275, the second lumen 289 of the second part 277, and the fluid outlet 238. In some embodiments, a conduit, not shown herein, may be coupled to the fluid outlet 238 and the dressing 110 to couple the canister 115 to the dressing 110. In some embodiments, the fluid path from the second fluid chamber 284 to the dressing 110 may be an instillation fluid path 303.

[0089] In some embodiments, the fluid 302 may be pre-filled in the second fluid chamber 284. For example, the fluid 302 may be added to the second fluid chamber 284 of the canister body 202 during assembly of the canister 115. During operation, the fluid 302 may be stored in the second fluid chamber 284 until it is desired to provide infusion therapy to the tissue site. When infusion therapy is desired, the controller 130 may be configured to operate the positive pressure source 150 to draw the fluid 302 from the second fluid chamber 284 through the infusion fluid pathway 303. In some embodiments, the controller 130 may operate the positive pressure source to move the fluid 302 through the infusion fluid pathway 303 and into the dressing 110 until the second fluid chamber 284 is empty.

[0090] 3B is a cross-sectional view of the recirculation canister 115 of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating a negative pressure mode of operation. The canister 115 may be fluidly coupled between the negative pressure source 105 and the dressing 110. The controller 130 may activate the negative pressure source 105, such that fluid 308 from the dressing 110 may be drawn from the dressing 110 into the first fluid chamber 282. In some embodiments, the negative pressure source 105 may be configured to terminate the negative pressure mode of operation when the first sensor 243 detects a predetermined fill level in the first fluid chamber 282.

[0091] There may be a conduit, not shown herein, that may couple the dressing 110 to the fluid inlet 236. The fluid 308 may be drawn from the dressing 110 through the conduit and into the first fluid chamber 282. The path that the fluid 308 follows from the dressing 110 to the first fluid chamber 282 may be a negative pressure path 310. The negative pressure path 310 may be offset from the instillation fluid path 303. For example, the negative pressure path 310 may direct the fluid 308 from the fluid inlet 236 toward the first side 222 of the canister body 202 to reach the first fluid chamber 282. By isolating the negative pressure path 310 from the instillation fluid path 303, the fluid 308 may not contaminate or come into contact with the fluid 302.

[0092] FIG. 3C is a cross-sectional view of the recirculation canister of FIG. 2A along line 2E-2E of FIG. 2D, illustrating fluid filtering from the first fluid chamber 282 of the canister 115 to the second fluid chamber 284 of the canister 115. During a negative pressure mode of operation, the first fluid chamber 282 may be filled with fluid 308. The filter 206 may be configured to filter the fluid 308 from the first fluid chamber 282 to the second fluid chamber 284, as indicated by arrow 312. The fluid 308 may flow through the filter 206 naturally by gravity. In some embodiments, the fluid 308 may flow through the filter 206 due to a pressure differential between the first fluid chamber 282 and the second fluid chamber 284. More specifically, the fluid 308 may start from the first fluid chamber 282, then pass through the secondary filter 290, the filter carrier 286, and the primary filter 288, before reaching the second fluid chamber 284.

[0093] The fluid 308 in the first fluid chamber 282 may be wound exudate from a tissue site being treated by therapy system 100. As the fluid 308 passes through each element of filter 206, the fluid 308 may be purified and cleaned such that contaminants such as bacteria, red blood cells, and / or viruses are removed by either the primary filter 288 or the secondary filter 290, and the filtered or purified fluid entering the second fluid chamber 284 is of a quality that may be discarded down a drain or injected back into the tissue site being treated by therapy system 100. In some embodiments, the filter 206 may convert the fluid 308 to saline, or the fluid 302 may be converted to saline using the fluid change device 241 of the second fluid chamber 284. In other embodiments, the filter 206 may be configured to allow certain elements of the fluid 308 that may be beneficial to the tissue site to pass to the second fluid chamber 284 while capturing harmful or non-beneficial elements in at least one component of the filter 206. As described above, filter 206 may filter the fluid such that water (HO) molecules may pass through filter 206 while larger bacterial molecules are captured by filter 206. In some embodiments, filter 206 may be sized to capture bacteria and red blood cells and prevent them from entering second fluid chamber 284. Additionally, one or more of filter carrier 286, primary filter 288, or secondary filter 290 of filter 206 may be positively or negatively charged to capture bacteria while allowing plasma components to pass through filter 206. In some embodiments, filter 206 may also be configured to capture viruses to block or prevent them from passing through filter 206 and entering second fluid chamber 284.

[0094] FIG. 3D is a cross-sectional view of the recirculation canister of FIG. 2A taken along line 2E-2E of FIG. 2D, illustrating the second fluid chamber 284 of the canister 115 containing a liquid. The second fluid chamber 284 may contain fluid 314 that has traveled from the first fluid chamber 282 through the filter 206 to reach the second fluid chamber 284. In some embodiments, the fluid 314 may be the same as or similar to the fluid 302 infused from the second fluid chamber 284 into the tissue site, as described with reference to FIG. 3A. In some embodiments, once all of the fluid 308 has been filtered through the filter 206 and has become the fluid 314 stored in the second fluid chamber 284, the therapy system 100 may be ready to instill the fluid 314 from the second fluid chamber 284 into the tissue site. The process described with reference to FIGS. 3A-3D may be repeated for as many cycles as necessary to treat the tissue site. 3A-3D may be repeated as long as the filter 206 is considered to be of good quality. A filter may be considered to be of good quality if the fluid passing through the second fluid chamber 284 is of a desired quality. For example, if the filter 206 allows bacteria or other contaminants to enter the second fluid chamber 284, the filter 206 may not be considered of good quality. Additionally, if the filter 206 takes longer than a predetermined time to filter the fluid 308 from the first fluid chamber 282 to the second fluid chamber 284, the filter 206 may not be considered of good quality. More specifically, if a predetermined amount of fluid 308 does not flow through the filter 206 within a predetermined time, the filter 206 may have reached the end of its life and may need to be replaced.

[0095] 4A-4F show various views of an exemplary embodiment of the canister 115 of the therapy system 100 of FIG. 1. In some embodiments, the canister 115 may be reusable. FIG. 4A is an exploded view of the canister 115 that may be associated with some embodiments of FIG. 1. FIG. 4B is a front view of the canister 115 of FIG. 4A. FIG. 4C is a rear view of the canister 115 of FIG. 4A. FIG. 4D is a side view of the canister 115 of FIG. 4A. FIG. 4E is a cross-sectional view of the canister 115 of FIG. 4A along line 4E-4E of FIG. 4C. FIG. 4F is a cutaway view of the second fluid chamber of the reusable canister of FIG. 4A, illustrating additional details that may be associated with some exemplary embodiments.

[0096] The canister 115 may include a canister body 202, a canister plate 204, a filter 206, one or more negative pressure filters 208, and a plug 410. While not depicted herein, the canister 115 may additionally include one or more of a fluid change device 241, a first sterilization source 294, a second sterilization source 296, or a first sensor. In some embodiments, the fluid outlet 238 may be detachable from the canister body 202. For example, the canister 115 may be a reusable canister that can receive and drain fluid from a tissue site, and then be used again in therapy to receive more fluid from the tissue site. In these embodiments, instillation therapy may not be performed, and the canister body 202 may be formed without the fluid outlet 238.

[0097] In embodiments where the canister 115 may not be used to provide infusion therapy, the infusion system 210 may be removed. The canister plate 204 may include a port or opening 458. The opening 458 may be located centrally between the first side 246 and the second side 248, proximate the second end 244. The opening 458 may extend through the canister plate 204, allowing fluid communication across the canister plate 204. In some embodiments, an annular wall 459 may be coupled to the inner surface 256. The annular wall 459 may surround the opening 458 and be recessed into the interior 230 of the canister 115. In some embodiments, a bevel, chamfer, or fillet may be disposed at the junction of the annular wall 459 and the opening 458 to form a recess 460, which may surround the opening 458. In some embodiments, a recess 462 or cavity may be formed in the canister plate 204 adjacent to the opening 458. The recess 462 may be recessed into the canister plate 204. In some embodiments, the recess 462 may not allow fluid communication with the interior 230 of the canister 115 across the canister plate 204. In some embodiments, a portion of the recess 462 may be coupled to the recess 460. In some embodiments, the opening 458 may be configured to receive a plug 410.

[0098] The canister plate 204 may also include structures such as a baffle 464. The baffle 464 may be coupled to the inner surface 256 and recessed into the interior 230 of the canister 115. In some embodiments, the baffle 464 may be disposed on the inner surface 256 proximate the opening 458 and the annular wall 459. The baffle 464 may have a height greater than the annular wall 459. The baffle 464 may have an inverted V-shape with a central portion aligned with the center of the opening 458. The baffle 464 may have two side portions, a first side portion extending toward and terminating proximate the first side 246 and a second side portion extending toward and terminating proximate the second side 248. In some embodiments, the distal ends of the side portions may be disposed between a central portion of the baffle 464 and the second end 244 of the canister plate 204 .

[0099] The plug 410 may be configured to seat within the opening 458 and prevent fluid communication therethrough. In some embodiments, the plug 410 may include a stopper 472. In some embodiments, the stopper 472 may be a cylinder having a diameter substantially equal to the diameter of the opening 458. The stopper 472 may have a height substantially equal to the height of the annular wall 459 such that, when the stopper 472 is seated within the opening 458, an end of the stopper 472 may be flush with an end of the annular wall 459. In some embodiments, the stopper 472 may include one or more recesses 473 recessed therein. When the canister 115 is assembled, the recesses 473 may be exposed to the interior 230 and may contact the fluid stored within the canister 115. The plug 410 may additionally include a seal ring 474 coupled to the stopper 472. A sealing ring 474 may be coupled to the end of the stopper 472 opposite the recess 473. The plug 410 may also include a gripping portion 476 coupled to the sealing ring 474. During operation, the plug 410 may be inserted into the opening 458. The stopper 472 may be coupled to the canister plate 204 with an interference fit, preventing fluid flow through the opening 458. The sealing ring 474 may contact the recess 460 to provide an additional seal between the canister plate 204 and the plug 410. The gripping portion 476 may fit within the recess 462 such that the plug 410 may be flush with the outer surface 254 of the canister plate 204. The plug 410 may provide a fluid seal at the opening 458 of the canister plate 204 and prevent fluid communication with the interior 230 across the canister plate 204 through the opening 458. In some embodiments, the plug 410 may be removable, while in other embodiments, the plug 410 may be permanently attached to the canister plate 204. The plug 410 may be formed from any of the materials described above with respect to the canister body 202 and the canister plate 204.

[0100] Figure 5A is a cross-sectional view of the canister 115 of Figure 4A taken along line 4E-4E of Figure 4C, illustrating a negative pressure mode of operation. The negative pressure mode of operation may be substantially similar to the negative pressure mode of operation described above with reference to Figure 3B. For example, there may be a conduit, not shown here, that may couple the dressing 110 to the fluid inlet 236. Fluid 502 may be drawn from the dressing 110 through the conduit and into the first fluid chamber 282. The path that the fluid 502 follows from the dressing 110 to the first fluid chamber 282 may be a negative pressure path.

[0101] Figure 5B is a cross-sectional view of the canister 115 of Figure 4A along line 4E-4E of Figure 4C, illustrating a negative pressure mode of operation during which fluid 502 is being filtered from the first fluid chamber 282 of the canister 115 to the second fluid chamber 284 of the canister 115. In Figure 5B, the negative pressure source 105 is operating and the first fluid chamber 282 is partially filled with fluid 502. The second fluid chamber 284 is partially filled with fluid 508 that has been filtered through the filter 206. Arrows 510 may represent the process of fluid 502 being filtered through the filter 206. The process of filtering the fluid 502 through the filter 206 may be substantially similar to the process described above with reference to Figure 3C.

[0102] Fluid 502 may continue to be filtered through filter 206 until second fluid chamber 284 is substantially full of fluid 508. In some embodiments, first sensor 243 may be configured to determine when second fluid chamber 284 is full. In other embodiments, canister 115 may include an additional sensor that may be configured to determine when second fluid chamber 284 is full.

[0103] FIG. 5C is a cross-sectional view of the canister 115 of FIG. 4A taken along line 4E-4E in FIG. 4C, illustrating fluid being removed from the second fluid chamber 284 in the evacuation mode. The evacuation mode may follow the negative pressure operating mode to prevent fluid 502 from flowing into the first fluid chamber 282 during the evacuation mode. During the evacuation mode, the plug 410 may be removed from the opening 458. For example, a user may separate the canister 115 from the therapy system 100 to expose the plug 410. A user may grasp the gripping portion 476 and apply force to the plug 410 to unseat the sealing ring 474 and stopper 472 from the recess 460 and opening 458, respectively. When the plug 410 is removed from the canister 115, the fluid 508 in the second fluid chamber 284 may flow through the opening 458 and exit the canister 115. Arrow 512 may represent the flow of fluid 508 out of second fluid chamber 284. Fluid 508 may be of a quality that can be disposed of down a standard drain and does not need to be treated as medical waste. Purifying fluid 502 into fluid 508 by filter 206 may allow a user to empty canister 115 and continue using canister 115 and therapy system 100 after canister 115 is emptied. In some embodiments, canister 115 may allow a user to repeatedly operate multiple negative pressure therapy cycles with therapy system 100 in a home environment. For example, once canister 115 is filled, a user may discard fluid 508 from second fluid chamber 284, reinstall canister 115 in therapy system 100, and continue therapy.

[0104] 5A-5D may be repeated until therapy of the tissue site is complete. In some embodiments, the process may be repeated until the life cycle of the filter 206 is reached. For example, if a predetermined amount of fluid 502 does not flow through the filter 206 within a predetermined time, the filter 206 may have reached the end of its life and the filter 206 may be replaced.

[0105] 6A is an assembled view of another embodiment of a portion of plug 410 and canister plate 204, illustrating additional details that may be associated with some embodiments. In some embodiments, opening 458 may be a linear hole formed through canister plate 204. Opening 458 may be bounded by a substantially cylindrical wall having threads 610 formed thereon. In some embodiments, opening 458 may have a seat 611 formed therein adjacent inner surface 256. Seat 611 may provide a ledge having a surface facing away from interior 230.

[0106] In some embodiments, the plug 410 is configured to be coupled to the canister plate 204 at the opening 458 via a pair of mating threads. The plug 410 may include a fastener 602 and a seal 604. In some embodiments, the fastener 602 may be a disk-shaped body having a sidewall. In some embodiments, the sidewall may further include threads 603. The threads 603 may be configured to mate with the threads 610. In some embodiments, the fastener 602 may include a recess 606 and a protrusion 608. For example, the recess 606 may be located on a surface of the fastener 602 configured to face away from the interior 230. The recess 606 may be recessed into the surface of the fastener 602. In some embodiments, the recess 606 may be located near an edge of the surface of the fastener 602. In other embodiments, the recess 606 may be located near a center of the surface of the fastener 602. The protrusions 608 may be disposed on a surface of the fastener 602 configured to face away from the interior 230. The protrusions 608 may be aligned with the recesses 606. For example, the protrusions 608 may have an axis aligned with the center of the recesses 606. In some embodiments, the recesses 606 and the protrusions 608 provide a texture to the surface of the fastener 602, allowing a user to apply sufficient force to the fastener 602 to secure it to or remove it from the canister plate 204.

[0107] The seal 604 may be a ring configured to fit within the opening 458 of the canister plate 204. The seal 604 may be configured to be disposed on a seat 611 within the opening 458. The fastener 602 may be secured to the canister plate 204 via threads 603 and threads 610 to compress the seal between the fastener 602 and the seat 611.

[0108] Figure 6B is a perspective view of a portion of the plug 410 and canister plate 204 of Figure 6A, illustrating additional details that may be associated with some embodiments. As shown in Figure 6B, the fastener 602 can be rotated in a clockwise or counterclockwise motion when the fastener 602 is adjacent to the opening 458. The threads 603 can engage with the threads 610 of the opening 458 to secure the plug 410 to the canister plate 204. In some embodiments, the surface of the fastener 602, including the recesses 606 and protrusions 608, can be flush with the outer surface 254 of the canister plate 204.

[0109] 6C is an assembled view of another embodiment of a portion of the plug 410 and canister plate 204, illustrating additional details that may be associated with some embodiments. As shown in FIG. 6C, the opening 458 may have a generally rectangular shape with semicircular ends. Generally, the straight sides of the opening 458 may be oriented proximate the second end 244. Each of the semicircular ends may be proximate the first side 246 and the second side 248, respectively. In some embodiments, a recess 462 may extend from the opening 458 toward the first end 242 of the canister plate 204.

[0110] In some embodiments, plug 410 may have a first section 620 and a second section 622. First section 620 may be shaped to mate with opening 458 such that first section 620 may be inserted into opening 458. In some embodiments, first section 620 may be configured to substantially fill and seal opening 458. In some embodiments, first section 620 may include a central portion 624 and one or more gripping portions 626 surrounding central portion 624. Second section 622 may extend from first section 620. For example, second section 622 may have a first end configured to be coupled to a straight side of first section 620. Second section 622 may extend away from first section 620 such that the second end of second section 622 may be separated from first section 620. In some embodiments, the second end of the second section 622 may be coupled to the canister plate 204 proximate the opening 458. For example, the second end of the second section 622 may be disposed within the recess 462 and coupled to the canister plate 204. In some embodiments, the second section 622 may include a hinge 623. The hinge 623 may be disposed between the first end and the second end of the second section 622. In some embodiments, the hinge 623 may be configured to allow the first section 620 to swing away from the canister plate 204 along at least one axis of rotation.

[0111] Figure 6D is a perspective view of a portion of the plug 410 and canister plate 204 of Figure 6C, illustrating additional details that may be associated with some embodiments. As shown in Figure 6D, the second section 622 may couple the plug 410 to the canister plate 204 such that the plug 410 may remain connected to the canister plate 204 when the first section 620 is removed from the opening 458. To remove the plug 410 from the opening 458, a user can grasp the central portion 624 by inserting one or more fingers into one or more gripping portions 626 and pull the first section 620 from the opening 458. The second section 622 may remain in contact with the canister plate 204 to prevent the plug 410 from being lost or discarded while fluid is being removed from the canister 115. In some embodiments, the baffle 464 may be shaped to accommodate the opening 458 of Figures 6C and 6D.

[0112] FIG. 6E is an assembled view of another embodiment of a plug 410 and a portion of the canister plate 204, illustrating additional details that may be associated with some embodiments. The plug 410 and opening 458 may include a sliding door-type mechanism. As shown in FIG. 6E, the plug 410 can be in an open position. The opening 458 may be generally rectangular with semicircular ends. The straight portions of the opening 458 may be oriented adjacent to the first side 246 and the second side 248, respectively. In some embodiments, the semicircular portions may be oriented adjacent to the first end 242 and the second end 244 of the canister plate 204. The semicircular portions of the opening 458 may have a diameter substantially equal to the diameter of the plug 410, allowing the plug 410 to fit within the opening 458. The plug section 630 may be incorporated into the canister plate 204 such that at least a portion of the plug 410 may be within the plug section 630 of the canister plate 204 in both the closed and open positions of the plug. The plug section 630 may extend from the opening 458 toward the first end 242 of the canister plate 204. The plug section 630 may be a hollow portion of the canister plate 204 between the outer surface 254 and the inner surface 256 of the canister plate 204.

[0113] The plug 410 may include a contact portion 632 and a sliding portion 634. The contact portion 632 may extend past the outer surface 254 so that a user can engage the contact portion 632. The sliding portion 634 may be received by a plug section 630 of the canister plate 204. The sliding portion 634 may extend partially into the plug section 630 when the plug 410 is configured to close the opening from the ambient environment. The sliding portion 634 may be fully inserted into the plug section 630 when the opening 458 is exposed to allow fluid to be removed from the canister 115. By sliding within the plug section 630 to close and expose the opening 458, the plug 410 may be configured to remain in contact with the canister plate 204 so that the plug 410 is not lost or discarded while fluid is being removed from the canister 115.

[0114] 6G is an assembled view of another embodiment of a plug 410 and a portion of the canister plate 204, illustrating additional details that may be associated with some embodiments. In some embodiments, the opening 458 may be a linear hole formed through the canister plate 204. The opening 458 may be bounded by a substantially circular wall configured to accommodate the plug 410. In some embodiments, the opening 458 may include a seat 639 formed within the opening 458 adjacent the inner surface 256 of the canister plate 204.

[0115] In some embodiments, plug 410 may include an outer wall 641 that may engage seat 639 of opening 458. Plug 410 may include a cap 640 that may be coupled to a body 643 of plug 410 with a connector 642. In some embodiments, connector 642 may be a hinge that allows cap 640 to be opened while still connected to body 643 of plug 410.

[0116] Figure 6H is a perspective view of a portion of the plug 410 and canister plate 204 of Figure 6A, illustrating additional details that may be associated with some embodiments. As shown in Figure 6H, the cap 640 can be removed from the body 643 of the plug 410. In some embodiments, the body 643 of the plug 410 may be pulled away from the inner surface 256 of the canister plate 204 and toward the outer surface 254 for easier access to the cap 640.

[0117] 6A-6H , plug 410 may utilize the negative pressure within canister 115 while negative pressure source 105 operates to fluidly seal canister 115. Additionally, plug 410 may act as a spout to improve control when emptying canister 115. In some embodiments, baffle 464 may also help control fluid as it exits canister 115 through opening 458. In other embodiments, plug 410 and opening 458 may be different sizes, shapes, and configurations, but any may maintain a fluid seal to prevent fluid from leaking from canister 115 when plug 410 seals opening 458.

[0118] Referring to FIG. 7, another embodiment of the exemplary embodiment of the canister 115 of the therapy system 100 of FIG. 1 is shown. The canister 115 may be a recirculating canister similar to the canister 115 shown in FIGS. 2A-2E and 3A-3D. The canister 115 may be substantially similar to the canister of FIGS. 2A-2E and 3A-3D, but may include a fill inlet 702 that may be fluidly coupled to the second fluid chamber 284 via a fill path 704, which may be isolated from both the infusion fluid path 303 and the negative pressure path 310. The fill path 704 extends from the second fluid chamber 284 through the canister body 202 to the fill inlet 702 and may be connected to a conduit (not shown herein) that may be coupled to an external fluid source. In some embodiments, the fill path 704 may include a component of the infusion system 210. For example, fill path 704 may extend from second fluid chamber 284, through first lumen 283 of first part 271, second lumen 285 of second part 273, lumen 281 of conduit 276, first lumen 287 of first part 275, second lumen 289 of second part 277, fluid outlet 238, and fill inlet 702 to a conduit coupling the fill inlet to an external fluid source. Fill path 704 may be isolated from first fluid chamber 282 such that fluid from the external fluid source flows into second fluid chamber 284 without contacting filter 206 or first fluid chamber 282.

[0119] Referring to FIG. 8, another embodiment of the exemplary embodiment of the canister 115 of the therapy system 100 of FIG. 1 is shown. The canister 115 may be a combination recirculating canister and a reusable canister. In some embodiments, the canister 115 may be substantially similar to the canister of FIGS. 2A-2E and 3A-3D, but may include the plug 410 of any of the canister 115 embodiments of FIGS. 4A-4F, 5A-5C, and 6A-6H. The canister 115 may be configured to instill fluid from the second fluid chamber 284 into the dressing 110 or to empty fluid from the second fluid chamber 284 through an opening 458 in the canister plate 204. In some embodiments, the opening 458 may be configured to mate with the plug 410 and may include an extension or spout 1002 that extends from the inner surface 256 of the canister plate 204 away from the outer surface 254 of the canister plate 204. The spout 1002 may be configured to facilitate removal of fluid from the second fluid chamber 284.

[0120] 3A-3D. Additionally, during operation of therapy system 100, plug 410 may be removed from canister plate 204 to remove fluid from second fluid chamber 284. For example, if the fluid in second fluid chamber 284 is of a quality that should not be injected back into a tissue site, the fluid may be removed through spout 1002 of canister 115. Additionally, or alternatively, when treatment of a tissue site using therapy system 100 is complete, the fluid may be removed from second fluid chamber 284 and discarded.

[0121] In some embodiments, opening 458 may be configured to transport fluid from an external fluid source into second fluid chamber 284. More specifically, plug 410 may be removed from opening 458 to expose interior 230 of canister body 202 so that fluid from the external fluid source may be poured into canister 115. After fluid is disposed in second fluid chamber 284, plug 410 may be reinserted into opening 458 to seal canister 115. Canister 115 may then be used in therapy system 100 to treat a tissue site as described above with reference to FIGS. 3A-3D .

[0122] Also described herein are methods for treating a tissue site. The method may include placing a dressing 110 at the tissue site, fluidly coupling a negative pressure source 105 to the dressing 110, and fluidly coupling a canister 115 between the negative pressure source 105 and the dressing 110. The canister 115 may include a first fluid chamber 282, a second fluid chamber 284, and a filter 206. The first fluid chamber 282 may be configured to collect fluid from the tissue site. The filter 206 may be disposed between the first fluid chamber 282 and the second fluid chamber 284. The filter 206 may be configured to filter fluid from the tissue site as it travels through the filter 206 from the first fluid chamber 282 to the second fluid chamber 284. The method may further include operating a negative pressure source 105 to generate negative pressure in the dressing 110, drawing fluid from the tissue site into a first fluid chamber 282 of the canister 115 in response to the negative pressure, and filtering the fluid from the tissue site using a filter 206 as the fluid moves from the first fluid chamber 282 to the second fluid chamber 284.

[0123] In some embodiments, the method can further include instilling the filtered fluid in the second fluid chamber 284 into the tissue site. In some embodiments, the method can further include discarding the filtered fluid in the second fluid chamber 284. In some exemplary embodiments, discarding the filtered fluid in the second fluid chamber 284 can include removing the plug 410 from an exhaust port, such as the opening 458 of the second fluid chamber 284, and drawing the filtered fluid from the second fluid chamber 284 through the exhaust port.

[0124] In some exemplary embodiments, the method may further include purifying the fluid in first fluid chamber 282 with a UV-C source, such as first sterilization source 294 and second sterilization source 296. In some exemplary embodiments, the method may further include treating the filtered fluid in second fluid chamber 284 with a UV-C source, such as first sterilization source 294 and second sterilization source 296. In some exemplary embodiments, second fluid chamber 284 may be configured to receive and contain an instillation fluid.

[0125] In some exemplary embodiments, the method may further include filling the second fluid chamber 284 with an infusion fluid. In some exemplary embodiments, the method may further include fluidly coupling the second fluid chamber 284 to the dressing 110 and instilling the infusion fluid from the second fluid chamber 284 into the dressing 110. In some exemplary embodiments, filling the second fluid chamber 284 with the infusion fluid may include adding the infusion fluid from an external fluid source through a port, such as opening 458, in the second fluid chamber 284. In some exemplary embodiments, filling the second fluid chamber 284 with the infusion fluid may include coupling a fluid path, such as infusion fluid path 303 of the canister 115, to the external fluid source and operating a pump, such as positive pressure source 150, to draw fluid from the external fluid source into the second fluid chamber 284.

[0126] The systems, devices, and methods described herein may provide numerous advantages. For example, the canister 115 embodiments described herein may reduce the number of canister changes, reduce the size of the therapy system 100, and simplify the system for users and medical personnel to manage. Additionally, the canister 115 embodiments described herein may reduce waste because the filter 206 can clean and purify the fluid from the tissue site so that it can be disposed of down a drain and does not have to be treated as medical waste.

[0127] While illustrated in several exemplary embodiments, those skilled in the art will recognize that the systems, devices, and methods described herein are susceptible to various changes and modifications that fall within the scope of the appended claims. Furthermore, the description of various alternatives using terms such as "or" does not require mutual exclusivity unless clearly required by context, and the indefinite article "a" or "an" does not limit its subject matter to a single instance unless clearly required by context. Components may also be combined or excluded in various configurations for purposes of sale, manufacture, assembly, or use. For example, in some configurations, the dressing 110, the canister 115, or both may be excluded or separated from the other components for manufacture or sale. In other exemplary configurations, the controller 130 may also be manufactured, configured, assembled, or sold independently of the other components.

[0128] The appended claims set forth novel and inventive aspects of the subject matter described above, but the claims may also encompass additional subject matter not specifically described. For example, certain features, elements, or aspects may be omitted from the claims if they are not necessary to distinguish the novel and inventive features from those known to those skilled in the art. Features, elements, and aspects described in the context of some embodiments may also be omitted, combined, or replaced by alternative features serving the same, equivalent, or similar purpose without departing from the scope of the invention as defined by the appended claims.

Claims

1. 1. A canister for use in a negative pressure wound therapy system, said canister comprising: a first fluid chamber configured to receive fluid from the tissue site; a second fluid chamber; and a filter disposed between the first fluid chamber and the second fluid chamber, the filter configured to filter the fluid from the tissue site as the fluid moves from the first fluid chamber to the second fluid chamber.

2. The filter is a filter carrier configured to be coupled to the canister between the first fluid chamber and the second fluid chamber; a primary filter coupled to the filter carrier and positioned adjacent to the second fluid chamber; 10. The canister of claim 1, further comprising: a secondary filter coupled to the filter carrier and positioned adjacent to the first fluid chamber.

3. The canister of claim 1 , further comprising an instillation fluid pathway configured to fluidly couple the second fluid chamber to the tissue site.

4. 4. The canister of claim 3, wherein the instillation fluid path is disposed along the exterior of the canister.

5. 4. The canister of claim 3, wherein the instillation fluid path is isolated from the first fluid chamber.

6. The canister of claim 3 , further comprising a negative pressure pathway configured to fluidly couple the first fluid chamber to the tissue site.

7. 7. The canister of claim 6, wherein the negative pressure path is isolated from the instillation fluid path.

8. 7. The canister of claim 6, further comprising a fill path configured to fluidly couple the second fluid chamber to an external fluid source.

9. 9. The canister of claim 8, wherein the fill path is isolated from the negative pressure path and the instillation fluid path.

10. 4. The canister of claim 3, further comprising a sensor disposed in the instillation fluid path, the sensor configured to generate a signal representative of a fill state of the second fluid chamber.

11. 10. The canister of claim 1, further comprising a first sterilization source configured to sterilize the first fluid chamber and a second sterilization source configured to sterilize the second fluid chamber.

12. 12. The canister of claim 11, wherein the first sterilization source and the second sterilization source are UV-C light emitting devices.

13. 10. The canister of claim 1, further comprising a fluid change device disposed within the second fluid chamber, the fluid change device configured to release a chemical into a fluid disposed within the second fluid chamber.

14. 14. The canister of claim 13, wherein the fluid change device is configured to sterilize the fluid in the second fluid chamber.

15. 14. The canister of claim 13, wherein the fluid-altering device is configured to alter a property of the fluid in the second fluid chamber.

16. The canister of claim 1 , further comprising a negative pressure filter disposed within the first fluid chamber and configured to prevent liquid from the tissue site from contacting a negative pressure source.

17. The canister of claim 1 , wherein the second fluid chamber comprises a port.

18. 18. The canister of claim 17, wherein the port is located at an end of the second fluid chamber opposite the first fluid chamber.

19. 18. The canister of claim 17, further comprising a plug configured to removably couple to the port.

20. 18. The canister of claim 17, wherein the port comprises a spout.

21. 10. The canister of claim 1, further comprising a sensor disposed within the first fluid chamber, the sensor configured to generate a signal representative of a fill state of the first fluid chamber.

22. 1. A system for treating a tissue site, the system comprising: a dressing configured to be placed at the tissue site; a negative pressure source configured to be fluidly coupled to the dressing and further configured to generate negative pressure at the tissue site; a canister configured to be fluidly coupled between the dressing and the negative pressure source, a first fluid chamber configured to receive fluid from the tissue site; a second fluid chamber configured to store a fluid; a canister comprising a filter disposed between the first fluid chamber and the second fluid chamber, the filter configured to filter the fluid from the tissue site as the fluid moves from the first fluid chamber to the second fluid chamber through the filter.

23. 23. The system of claim 22, further comprising an instillation fluid pathway configured to fluidly couple the second fluid chamber to the tissue site.

24. 24. The system of claim 23, further comprising a negative pressure pathway configured to fluidly couple the negative pressure source to the dressing and the first fluid chamber of the canister, the negative pressure pathway being isolated from the infusion fluid pathway.

25. 1. A method of treating a tissue site, the method comprising: placing a dressing at the tissue site; fluidly coupling a source of negative pressure to the dressing; a canister between the negative pressure source and the dressing, a first fluid chamber configured to collect fluid from the tissue site; a second fluid chamber; and fluidly coupling a canister comprising: a filter disposed between the first fluid chamber and the second fluid chamber, the filter configured to filter the fluid from the tissue site as the fluid travels through the filter from the first fluid chamber to the second fluid chamber; operating the negative pressure source to generate negative pressure in the dressing; drawing fluid from the tissue site into the first fluid chamber of the canister in response to the negative pressure; filtering the fluid from the tissue site with the filter as the fluid moves from the first fluid chamber to the second fluid chamber.

26. 26. The method of claim 25, further comprising instilling the filtered fluid in the second fluid chamber into the tissue site.

27. 26. The method of claim 25, further comprising discarding the filtered fluid in the second fluid chamber.

28. 28. The method of claim 27, wherein discarding the filtered fluid in the second fluid chamber comprises removing a plug from an exhaust port of the second fluid chamber and draining the filtered fluid from the second fluid chamber through the exhaust port.

29. 26. The method of claim 25, further comprising purifying the fluid in the first fluid chamber with a UV-C source.

30. 26. The method of claim 25, further comprising treating the filtered fluid in the second fluid chamber with a UV-C source.

31. 26. The method of claim 25, wherein the second fluid chamber is configured to receive and contain an instillation fluid.

32. 26. The method of claim 25, further comprising filling the second fluid chamber with an instillation fluid.

33. 33. The method of claim 32, further comprising fluidly coupling the second fluid chamber to the dressing and instilling the instillation fluid from the second fluid chamber into the dressing.

34. 33. The method of claim 32, wherein filling the second fluid chamber with the instillation fluid comprises adding the instillation fluid from an external fluid source through a port in the second fluid chamber.

35. 33. The method of claim 32, wherein filling the second fluid chamber with the instillation fluid comprises coupling a fluid path of the canister to an external fluid source and operating a pump to draw fluid from the external fluid source into the second fluid chamber.

36. 10. A system, apparatus, and method substantially as described herein.

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