Patent Description:
The present disclosure relates at least to apparatuses, systems, and methods for the treatment of wounds, for example, using dressings in combination with negative pressure or non-negative pressure wound therapy.

Many different types of wound dressings are known for aiding in the healing process of a human or animal. These different types of wound dressings include many different types of materials and layers, for example, gauze, pads, foam pads or multi-layer wound dressings. Topical negative pressure therapy, sometimes referred to as vacuum assisted closure, negative pressure wound therapy, or reduced pressure wound therapy, is widely recognized as a beneficial mechanism for improving the healing rate of a wound. Such therapy is applicable to a broad range of wounds such as incisional wounds, open wounds and abdominal wounds or the like.

Dressings for use in wound therapy, however, may provide little visualization or other information about the condition of a wound site beneath the dressings. As a result, in order to allow a clinician to inspect the healing or status of a wound, a dressing may be changed prematurely, such as before a desired level of wound healing has occurred or a full absorbent capacity of the dressings has been reached.

<CIT> discloses a smart sensor used for measuring the extent of healing of a wound, and a method for fabricating same.

<CIT> discloses biodegradable waveguides and their uses with devices, such as medical devices.

<CIT> discloses an optical sensor component for use in an optical sensor for monitoring of protease activity in wound fluid.

<CIT> discloses a system and method for monitoring the extent of wound healing.

<CIT> discloses a multifunctional wound treatment dressing for administering a plurality of different therapeutic treatments to an open, chronic wound of a human or animal body.

<CIT> discloses a device for wound treatment, comprising a chamber that includes an inner surface and defines a treatment space, the chamber being made of a flexible, impermeable material.

A negative pressure wound treatment apparatus according to the invention is disclosed in claim <NUM>.

The negative pressure wound treatment apparatus of the preceding paragraph can include one or more of the following features: The negative pressure wound treatment apparatus can include a mechanochromic material configured to indicate the pressure. The processor can activate an indicator responsive to the measurement value. The emitter can be positioned proximate to an end of the first optical fiber. The first optical fiber can include a notch or a slit from which the first electromagnetic radiation exits the first optical fiber. The first electromagnetic radiation or the second electromagnetic radiation can have a wavelength between <NUM> and <NUM>. An end of the first optical fiber can be truncated at an angle so that the first electromagnetic radiation exiting the end of the first optical fiber scatters. The wound dressing can include a wound filler and a wound cover, and the first optical fiber and the second optical fiber can extend through the wound filler and the wound cover. The emitter and the detector can be positioned within a non-sterile portion of the wound dressing. The negative pressure wound treatment apparatus can include: a polarizer configured to polarize the first electromagnetic radiation passing through the first optical fiber; or a filter configured to filter the first electromagnetic radiation passing through the first optical fiber. The plurality of optical fibers can include a third optical fiber that can pass a different wavelength of electromagnetic radiation than the first optical fiber. The first optical fiber and the second optical fiber can extend parallel to a direction in which the wound dressing extends. The first optical fiber and the second optical fiber can extend perpendicular to a direction in which the wound dressing extends. The negative pressure wound treatment apparatus can include a plurality of detectors including the detector, and the plurality of detectors can be positioned around the emitter. The second electromagnetic radiation can include a portion of the first electromagnetic radiation that reflected off of the wound.

A method is disclosed herein that can include: collecting exudate with a wound dressing positioned over a wound; emitting first electromagnetic radiation into a first optical fiber of a plurality of optical fibers, the plurality of optical fibers being positioned at least partly in the wound dressing; passing the first electromagnetic radiation with the first optical fiber; passing second electromagnetic radiation with a second optical fiber of the plurality of optical fibers; generating a signal responsive to the second electromagnetic radiation exiting the second optical fiber; and determining from the signal a measurement value indicative of a temperature of the wound or a pressure at the wound.

The method of the preceding paragraph can include one or more of the following features: The method can include indicating the pressure using a mechanochromic material, the measurement value being indicative of the pressure. The method can include changing a color of a thermochromic material responsive to the temperature, the measurement value being indicative of the temperature. The method can include indicating the temperature using an optical thermometer, the measurement value being indicative of the temperature. The method can include providing positive pressure or negative pressure to the wound responsive to the measurement value. The method can include activating an indicator responsive to the measurement value. The second electromagnetic radiation can include a portion of the first electromagnetic radiation that reflected off of the wound.

A wound dressing can include optical fibers (sometimes referred to as light pipes) that are integrated in the wound dressing and may, for example, be positioned in-plane or through-plane relative to the wound dressing. One or more of the optical fibers can transmit electromagnetic radiation (for instance, having a wavelength between about <NUM> and about <NUM>, such as at <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> or in a range between two of the aforementioned wavelengths like between <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM> or in a range of visible light [such as blue light, green light, or red light] or infrared light) from one or more emitters (for example, light sources like light emitting diodes (LEDs)) to a wound underneath the wound dressing. The electromagnetic radiation passed by the optical fibers from the one or more emitters can scatter off of the wound, and the scattered electromagnetic radiation may be captured by one or more of the optical fibers and transmitted to one or more detectors. The output from the one or more detectors can desirably, in certain implementations, be used to investigate a condition of the wound without removing the wound dressing once placed over the wound.

The use of the optical fibers as disclosed herein can, in certain implementations, advantageously permit the delivery or detection of electromagnetic radiation from emitters or detectors that may be located away from the wound or safely isolated within the wound dressing. As a result, the emitters or detectors or other associated electronics can be located in a manner that reduces or limits an electrical safety risk from use of the emitters or detectors or other associated electronics.

The integration of optical fibers into or around a wound dressing can permit investigation of a wound by analyzing electromagnetic radiation returning from or around a wound. Such electromagnetic radiation can include information on a wound condition, color, temperature, pH, pressure, infection, among other possibilities. The investigation can be facilitated through use of one or more of (i) direct optical measurement or observation of a wound or local tissue, (ii) temperature identification by a color changing thermochromic material (where a change in color is associated with a change in temperature), (iii) optical identification of an absence of negative pressure generated by presence or absence of total internal reflection within an optical fiber, (iv) presence or absence of positive pressure (load) generated by mechanochromic (pressure-sensitive) material, (v) presence or absence of negative pressure generated by mechanochromic (pressure-sensitive) material, (vi) presence of positive pressure (load) generated by failure of the optical fiber material or loss of optical signal, (vii) multiplexing techniques whereby electromagnetic radiation is polarized for sectionable area interrogation, or (viii) optical measurement of pH by color changing pH sensitive materials, such as dyes or gels, and which may be encapsulated within a wound dressing.

Fiber optic tubes can run from emitters or detectors and allow electronics to be placed away from the wound and load bearing parts. The emitters and detectors can then have an optical path running out to the light pipes or all the way to a wound. The fiber optic tubes can include a polymer for encapsulation, silicone gel, or tubing.

The features described herein can provide one or more of the following advantages: the optical fibers can allow tighter light cones into a wound, electronics may not be positioned within a sterile portion of a wound dressing, electronics may not be positioned proximal to a wound that may also be exuding or challenged by liquid, electronics may not be positioned proximal to a wound and thus may not cause pressure points or introduce uneven topography near the wound, and electronics can be positioned proximal to a wound but pressure points or uneven topography may be shielded by an intermediary material.

The electromagnetic radiation emitted by an emitter can, for example, have one or more wavelengths between <NUM> and <NUM>, such as at <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> or in a range between two of the aforementioned wavelengths (such as between <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM>) or in a range of visible light (such as blue light, green light, or red light) or infrared light, in some implementations. In other implementations, another one or more wavelengths of electromagnetic radiation may be emitted that is less than <NUM> or greater than <NUM>. The emitter can cycle or transition between different wavelengths of electromagnetic radiation in order to obtain different measurements from or near a wound. There can be different optical fibers that may be constructed or assigned to emit electromagnetic radiation of different wavelengths. Further, one or more polarizers can polarize the electromagnetic radiation passing through the optical fibers or one or more filters can filter the electromagnetic radiation passing through the optical fibers.

Aspects disclosed herein at least partly relate to apparatuses and methods of monitoring and treating biological tissue with sensor-enabled substrates. The aspects disclosed herein are not limited to treatment or monitoring of a particular type of tissue or injury, instead the sensor-enabled technologies disclosed herein are broadly applicable to any type of therapy that may benefit from sensor-enabled substrates. Some implementations utilize sensors and data collection relied upon by health care providers to make both diagnostic and patient management decisions.

Some aspects disclosed herein relate to the use of sensors mounted on or embedded within substrates configured to be used in the treatment of both intact and damaged human or animal tissue. Such sensors may collect information about the surrounding tissue and transmit such information to a computing device or a caregiver to be utilized in further treatment.

The sensor embodiments disclosed herein may be used in combination with clothing. Non-limiting examples of clothing for use with embodiments of the sensors disclosed herein include shirts, pants, trousers, dresses, undergarments, outer-garments, gloves, shoes, hats, and other suitable garments. In certain embodiments, the sensor embodiments disclosed herein may be welded into or laminated into/onto the particular garments. The sensor embodiments may be printed directly onto the garment and/or embedded into the fabric.

Sensor embodiments disclosed herein may be incorporated into cushioning or bed padding, such as within a hospital bed, to monitor patient characteristics, such as any characteristic disclosed herein.

The sensor embodiments disclosed herein may be utilized in rehabilitation devices and treatments, including sports medicine. For example, the sensor embodiments disclosed herein may be used in braces, sleeves, wraps, supports, and other suitable items. Similarly, the sensor embodiments disclosed herein may be incorporated into sporting equipment, such as helmets, sleeves, and/or pads.

The sensor embodiments disclosed herein may be used in coordination with surgical devices, for example, the NAVIO surgical system by Smith & Nephew Inc. In implementations, the sensor embodiments disclosed herein may be in communication with such surgical devices to guide placement of the surgical devices. To further aid in surgical techniques, the sensors disclosed herein may be incorporated into a surgical drape to provide information regarding tissue under the drape that may not be immediately visible to the naked eye.

Sensor embodiments as disclosed herein may also be utilized for pre-surgical assessment. For example, such sensor embodiments may be used to collect information about a potential surgical site, such as by monitoring skin and the underlying tissues for a possible incision site. For example, perfusion levels or other suitable characteristics may be monitored at the surface of the skin and deeper in the tissue to assess whether an individual patient may be at risk for surgical complications. Sensor embodiments such as those disclosed herein may be used to evaluate the presence of microbial infection and provide an indication for the use of antimicrobials. Further, sensor embodiments disclosed herein may collect further information in deeper tissue, such as identifying pressure ulcer damage or the fatty tissue levels.

The sensor embodiments disclosed herein may be utilized in cardiovascular monitoring. For example, such sensor embodiments may be incorporated into a flexible cardiovascular monitor that may be placed against the skin to monitor characteristics of the cardiovascular system and communicate such information to another device or a caregiver.

The sensor embodiments disclosed herein may be incorporated into implantable devices, such as implantable orthopedic implants, including flexible implants. Such sensor embodiments may be configured to collect information regarding the implant site and transmit this information to an external source.

Sensor embodiments as disclosed herein may be incorporated into Ear, Nose, and Throat (ENT) applications. For example, such sensor embodiments may be utilized to monitor recovery from ENT-related surgery, such as wound monitoring within the sinus passage.

As described in greater detail below, the sensor embodiments disclosed herein may encompass sensor printing technology with encapsulation, such as encapsulation with a polymer film. Such a film may be constructed using any polymer described herein, such as polyurethane. Encapsulation of the sensor embodiments may provide waterproofing of the electronics and protection from local tissue, local fluids, and other sources of potential damage.

Embodiments disclosed herein at least partly relate to apparatuses and methods of treating a wound with or without reduced pressure, including for example a source of negative pressure and wound dressing components and apparatuses. The apparatuses and components comprising the wound overlay and packing materials or internal layers, if any, are sometimes collectively referred to herein as dressings. In some embodiments, the wound dressing can be provided to be utilized without reduced pressure.

Some embodiments disclosed herein relate to wound therapy for a human or animal body. Therefore, any reference to a wound herein can refer to a wound on a human or animal body, and any reference to a body herein can refer to a human or animal body. The disclosed technology embodiments may relate to preventing or minimizing damage to physiological tissue or living tissue, or to the treatment of damaged tissue (for example, a wound as described herein).

As used herein the expression "wound" may include an injury to living tissue may be caused by a cut, blow, or other impact, typically one in which the skin is cut or broken. A wound may be a chronic or acute injury. Acute wounds occur as a result of surgery or trauma. They move through the stages of healing within a predicted timeframe. Chronic wounds typically begin as acute wounds. The acute wound can become a chronic wound when it does not follow the healing stages resulting in a lengthened recovery. It is believed that the transition from acute to chronic wound can be due to a patient being immuno-compromised.

Chronic wounds may include for example: venous ulcers (such as those that occur in the legs), which account for the majority of chronic wounds and mostly affect the elderly, diabetic ulcers (for example, foot or ankle ulcers), peripheral arterial disease, pressure ulcers, or epidermolysis bullosa (EB).

Examples of other wounds include, but are not limited to, abdominal wounds or other large or incisional wounds, either as a result of surgery, trauma, sterniotomies, fasciotomies, or other conditions, dehisced wounds, acute wounds, chronic wounds, subacute and dehisced wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, bums, diabetic ulcers, pressure ulcers, stoma, surgical wounds, trauma and venous ulcers or the like.

Wounds may also include a deep tissue injury. Deep tissue injury is a term proposed by the National Pressure Ulcer Advisory Panel (NPUAP) to describe a unique form of pressure ulcers. These ulcers have been described by clinicians for many years with terms such as purple pressure ulcers, ulcers that are likely to deteriorate and bruises on bony prominences.

Wound may also include tissue at risk of becoming a wound as discussed herein. For example, tissue at risk may include tissue over a bony protuberance (at risk of deep tissue injury/insult) or pre-surgical tissue (for example, knee tissue) that may has the potential to be cut (for example, for joint replacement/surgical alteration/reconstruction).

Some aspects relate to methods of treating a wound with the technology disclosed herein in conjunction with one or more of the following: advanced footwear, turning a patient, offloading (such as, offloading diabetic foot ulcers), treatment of infection, systemix, antimicrobial, antibiotics, surgery, removal of tissue, affecting blood flow, physiotherapy, exercise, bathing, nutrition, hydration, nerve stimulation, ultrasound, electrostimulation, oxygen therapy, microwave therapy, active agents ozone, antibiotics, antimicrobials, or the like.

Alternatively or additionally, a wound may be treated using topical negative pressure and/or traditional advanced wound care, which is not aided by the using of applied negative pressure (may also be referred to as non-negative pressure therapy).

Advanced wound care may include use of an absorbent dressing, an occlusive dressing, use of an antimicrobial and/or debriding agents in a wound dressing or adjunct, a pad (for example, a cushioning or compressive therapy, such as stockings or bandages), or the like.

Treatment of such wounds can be performed using traditional wound care, wherein a dressing can be applied to the wound to facilitate and promote healing of the wound.

Some aspects relate to methods of manufacturing a wound dressing comprising providing a wound dressing as disclosed herein.

The wound dressings that may be utilized in conjunction with the disclosed technology include any known dressing in the art. The technology is applicable to negative pressure therapy treatment as well as non-negative pressure therapy treatment.

A wound dressing can include one or more absorbent layer(s). The absorbent layer may be a foam or a superabsorbent.

Wound dressings may comprise a dressing layer including a polysaccharide or modified polysaccharide, a polyvinylpyrrolidone, a polyvinyl alcohol, a polyvinyl ether, a polyurethane, a polyacrylate, a polyacrylamide, collagen, or gelatin or mixtures thereof. Dressing layers comprising the polymers listed are known in the art as being useful for forming a wound dressing layer for either negative pressure therapy or non-negative pressure therapy.

The polymer matrix may be a polysaccharide or modified polysaccharide.

The polymer matrix may be a cellulose. Cellulose material may include hydrophilically modified cellulose such as methyl cellulose, carboxymethyl cellulose (CMC), carboxymethyl cellulose (CEC), ethyl cellulose, propyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose, carboxyethyl sulphonate cellulose, cellulose alkyl sulphonate, or mixtures thereof.

Cellulose material may be cellulose alkyl sulphonate. The alkyl moiety of the alkyl sulphonate substituent group may have an alkyl group having <NUM> to <NUM> carbon atoms, such as methyl, ethyl, propyl, or butyl. The alkyl moiety may be branched or unbranched, and hence suitable propyl sulphonate substituents may be <NUM>- or <NUM>-methyl-ethylsulphonate. Butyl sulphonate substituents may be <NUM>-ethyl-ethylsulphonate, <NUM>,<NUM>-dimethyl-ethylsulphonate, or <NUM>,<NUM>-dimethyl-ethylsulphonate. The alkyl sulphonate substituent group may be ethyl sulphonate. The cellulose alkyl sulphonate is described in <CIT>, <CIT>, <CIT>, or <CIT>.

Cellulose alkyl sulfonates may have varying degrees of substitution, the chain length of the cellulose backbone structure, and the structure of the alkyl sulfonate substituent. Solubility and absorbency are largely dependent on the degree of substitution: as the degree of substitution is increased, the cellulose alkyl sulfonate becomes increasingly soluble. It follows that, as solubility increases, absorbency increases.

A wound dressing can also comprise a top or cover layer.

The thickness of the wound dressing disclosed herein may be between <NUM> to <NUM>, or <NUM> to <NUM>, or <NUM> to <NUM>.

The disclosed technology may be used in conjunction with a non-negative pressure dressing. A non-negative pressure wound dressing suitable for providing protection at a wound site may comprise:.

The obscuring element may be partially translucent.

The obscuring element may be a masking layer.

The non-negative pressure wound dressing may further comprise a region in or adjacent the obscuring element for allowing viewing of the absorbent layer. For example, the obscuring element layer may be provided over a central region of the absorbent layer and not over a border region of the absorbent layer. The obscuring element can be of hydrophilic material or coated with a hydrophilic material.

The obscuring element may comprise a three-dimensional knitted spacer fabric. The spacer fabric is known in the art and may include a knitted spacer fabric layer.

The obscuring element may further comprise an indicator for indicating the need to change the dressing.

The obscuring element can be provided as a layer at least partially over the absorbent layer, further from a wound site than the absorbent layer in use.

The non-negative pressure wound dressing may further comprise a plurality of openings in the obscuring element for allowing fluid to move therethrough. The obscuring element may comprise, or may be coated with, a material having size-exclusion properties for selectively permitting or preventing passage of molecules of a predetermined size or weight.

The obscuring element may be configured to at least partially mask light radiation having wavelength of <NUM> and less.

The obscuring element may be configured to reduce light absorption by <NUM>% or more.

The obscuring element may be configured to yield a CIE L* value of <NUM> or more, and optionally <NUM> or more. The obscuring element may be configured to yield a CIE L* value of <NUM> or more.

The non-negative pressure wound dressing may further comprise at least one of a wound contact layer, a foam layer, an odor control element, a pressure-resistant layer and a cover layer.

The cover layer is present, and the cover layer is a translucent film. Typically, the translucent film has a moisture vapour permeability of <NUM>/m<NUM>/24hours or more.

The translucent film may be a bacterial barrier.

The non-negative pressure wound dressing as disclosed herein comprises the wound contact layer and the absorbent layer overlies the wound contact layer. The wound contact layer carries an adhesive portion for forming a substantially fluid tight seal over the wound site.

The non-negative pressure wound dressing as disclosed herein may comprise the obscuring element and the absorbent layer being provided as a single layer.

The non-negative pressure wound dressing disclosed herein can comprise the foam layer, and the obscuring element is of a material comprising components that may be displaced or broken by movement of the obscuring element.

The non-negative pressure wound dressing can comprise an odor control element or may not include an odor control element. When present, the odor control element may be dispersed within or adjacent the absorbent layer or the obscuring element. Alternatively, when present the odor control element may be provided as a layer sandwiched between the foam layer and the absorbent layer.

The disclosed technology for a non-negative pressure wound dressing can comprise a method of manufacturing a wound dressing, comprising: providing an absorbent layer for absorbing wound exudate; and providing an obscuring element for at least partially obscuring a view of wound exudate absorbed by the absorbent layer in use.

The non-negative pressure wound dressing may be suitable for providing protection at a wound site, comprising: an absorbent layer for absorbing wound exudate; and a shielding layer provided over the absorbent layer, and further from a wound-facing side of the wound dressing than the absorbent layer. The shielding layer may be provided directly over the absorbent layer. The shielding layer can comprise a three-dimensional spacer fabric layer.

The shielding layer increases the area over which a pressure applied to the dressing is transferred by <NUM>% or more or the initial area of application. For example the shielding layer increases the area over which a pressure applied to the dressing is transferred by <NUM>% or more, and optionally by <NUM>% or more, and optionally by <NUM>% or more.

The shielding layer may comprise <NUM> or more sub-layers, wherein a first sub-layer comprises through holes and a further sub-layer comprises through holes and the through holes of the first sub-layer are offset from the through holes of the further sub-layer.

The non-negative pressure wound dressing as disclosed herein may further comprise a permeable cover layer for allowing the transmission of gas and vapour therethrough, the cover layer provided over the shielding layer, wherein through holes of the cover layer are offset from through holes of the shielding layer.

The non-negative pressure wound dressing may be suitable for treatment of pressure ulcers.

A more detailed description of the non-negative pressure dressing disclosed hereinabove is provided in <CIT>, the entirety of which is hereby incorporated by reference.

The non-negative pressure wound dressing may be a multi-layered wound dressing comprising: a fibrous absorbent layer for absorbing exudate from a wound site; and a support layer configured to reduce shrinkage of at least a portion of the wound dressing.

The multi-layered wound dressing disclosed herein, further can comprise a liquid impermeable film layer, wherein the support layer is located between the absorbent layer and the film layer.

The support layer disclosed herein may comprise a net. The net may comprise a geometric structure having a plurality of substantially geometric apertures extending therethrough. The geometric structure may for example comprise a plurality of bosses substantially evenly spaced and joined by polymer strands to form the substantially geometric apertures between the polymer strands.

The net may be formed from high density polyethylene.

The apertures may have an area from <NUM> to <NUM><NUM>.

The support layer may have a tensile strength from <NUM> to <NUM>.

The support layer may have a thickness of from <NUM> to <NUM>.

The support layer may be located directly adjacent the absorbent layer. Typically, the support layer is bonded to fibers in a top surface of the absorbent layer. The support layer may further comprise a bonding layer, wherein the support layer is heat laminated to the fibers in the absorbent layer via the bonding layer. The bonding layer may comprise a low melting point adhesive such as ethylene-vinyl acetate adhesive.

The multi-layered wound dressing disclosed herein further can comprise an adhesive layer attaching the film layer to the support layer.

The multi-layered wound dressing disclosed herein further can comprise a wound contact layer located adjacent the absorbent layer for positioning adjacent a wound. The multi-layered wound dressing may further comprise a fluid transport layer between the wound contact layer and the absorbent layer for transporting exudate away from a wound into the absorbent layer.

A more detailed description of the multi-layered wound dressing disclosed hereinabove is provided in International Patent Application Publication No. <CIT>.

The disclosed technology may be incorporated in a wound dressing comprising a vertically lapped material comprising: a first layer of an absorbing layer of material, and a second layer of material, wherein the first layer being constructed from at least one layer of non-woven textile fibers, the non-woven textile fibers being folded into a plurality of folds to form a pleated structure. The wound dressing further can comprise a second layer of material that is temporarily or permanently connected to the first layer of material.

Typically the vertically lapped material has been slitted.

The first layer can have a pleated structure having a depth determined by the depth of pleats or by the slitting width. The first layer of material may be a moldable, lightweight, fiber-based material, blend of material or composition layer.

The first layer of material may comprise one or more of manufactured fibers from synthetic, natural or inorganic polymers, natural fibers of a cellulosic, proteinaceous or mineral source.

The wound dressing may comprise two or more layers of the absorbing layer of material vertically lapped material stacked one on top of the other, wherein the two or more layers have the same or different densities or composition.

The wound dressing may comprise only one layer of the absorbing layer of material vertically lapped material.

The absorbing layer of material is a blend of natural or synthetic, organic or inorganic fibers, and binder fibers, or bicomponent fibers typically PET with a low melt temperature PET coating to soften at specified temperatures and to act as a bonding agent in the overall blend.

The absorbing layer of material may be a blend of <NUM> to <NUM> % thermoplastic polymer, and <NUM> to <NUM> wt % of a cellulose or derivative thereof.

The wound dressing disclosed herein can have a second layer comprises a foam or a dressing fixative.

The foam may be a polyurethane foam. The polyurethane foam may have an open or closed pore structure.

The dressing fixative may include bandages, tape, gauze, or backing layer.

The wound dressing as disclosed herein can comprise the absorbing layer of material connected directly to a second layer by lamination or by an adhesive, and the second layer is connected to a dressing fixative layer. The adhesive may be an acrylic adhesive, or a silicone adhesive.

The wound dressing as disclosed herein further can comprise layer of a superabsorbent fiber, or a viscose fiber or a polyester fiber.

The wound dressing as disclosed herein further can comprise a backing layer. The backing layer may be a transparent or opaque film. Typically the backing layer comprises a polyurethane film (typically a transparent polyurethane film).

A more detailed description of the multi-layered wound dressing disclosed herein is provided in <CIT>.

The non-negative pressure wound dressing may comprise an absorbent component for a wound dressing, the component comprising a wound contacting layer comprising gel forming fibers bound to a foam layer, wherein the foam layer is bound directly to the wound contact layer by an adhesive, polymer based melt layer, by flame lamination or by ultrasound.

The absorbent component may be in a sheet form.

The wound contacting layer may comprise a layer of woven or non-woven or knitted gel forming fibers.

The foam layer may be an open cell foam, or closed cell foam, typically an open cell foam. The foam layer is a hydrophilic foam.

The wound dressing may comprise the component that forms an island in direct contact with the wound surrounded by periphery of adhesive that adheres the dressing to the wound. The adhesive may be a silicone or acrylic adhesive, typically a silicone adhesive.

The wound dressing may be covered by a film layer on the surface of the dressing furthest from the wound.

A more detailed description of the wound dressing of this type hereinabove is provided in <CIT>.

The non-negative pressure wound dressing may comprise a multi layered wound dressing for use on wounds producing high levels of exudate, characterized in that the dressing comprising: a transmission layer having an MVTR of at least <NUM> gm<NUM>/<NUM> hours, an absorbent core comprising gel forming fibers capable of absorbing and retaining exudate, a wound contacting layer comprising gel forming fibers which transmits exudate to the absorbent core and a keying layer positioned on the absorbent core, the absorbent core and wound contacting layer limiting the lateral spread of exudate in the dressing to the region of the wound.

The wound dressing may be capable of handling at least <NUM> (or <NUM> and <NUM>) of fluid per <NUM><NUM> of dressing in <NUM> hours.

The wound dressing may comprise gel forming fibers that are chemically modified cellulosic fibers in the form of a fabric. The fibers may include carboxymethylated cellulose fibers, typically sodium carboxymethylcellulose fiber.

The wound dressing may comprise a wound contact layer with a lateral wicking rate from <NUM> per minute to <NUM> per minute. The wound contact layer may have a fiber density between 25gm<NUM> and 55gm<NUM>, such as 35gm<NUM>.

The absorbent core may have an absorbency of exudate of at least <NUM>/g, and typically a rate of lateral wicking of less the <NUM> per minute.

The absorbent core may have a blend in the range of up to <NUM>% cellulosic fibers by weight and <NUM>% to <NUM>% gel forming fibers by weight.

Alternatively, the absorbent core may have a blend in the range of up to <NUM>% cellulosic fibers by weight and <NUM>% to <NUM>% gel forming fibers by weight. For example the blend is in the range of <NUM>% cellulosic fibers by weight and <NUM>% gel forming fibers by weight.

The fiber density in the absorbent core may be between 150gm<NUM> and 250gm<NUM>, or about <NUM> gm<NUM>.

The wound dressing when wet may have shrinkage that is less than <NUM> % or less than <NUM> % of its original size/dimension.

The wound dressing may comprise a transmission layer and the layer is a foam. The transmission layer may be a polyurethane foam laminated to a polyurethane film.

The wound dressing may comprise one or more layers selected from the group comprising a soluble medicated film layer; an odor-absorbing layer; a spreading layer and an additional adhesive layer.

The wound dressing may be <NUM> and <NUM> thick.

The wound dressing may be characterized in that the keying layer bonds the absorbent core to a neighboring layer. The keying layer may be positioned on either the wound facing side of the absorbent core or the non-wound facing side of the absorbent core. The keying layer can be positioned between the absorbent core and the wound contact layer. The keying layer may be a polyamide web.

The non-negative pressure wound dressing may be a compression bandage. Compression bandages are known for use in the treatment of oedema and other venous and lymphatic disorders, e.g., of the lower limbs.

A compression bandage systems typically employ multiple layers including a padding layer between the skin and the compression layer or layers. The compression bandage may be useful for wounds such as handling venous leg ulcers.

The compression bandage may comprise a bandage system comprising an inner skin facing layer and an elastic outer layer, the inner layer comprising a first ply of foam and a second ply of an absorbent nonwoven web, the inner layer and outer layer being sufficiently elongated so as to be capable of being wound about a patient's limb. A compression bandage of this type is disclosed in <CIT>.

The compression bandage system comprises: a) an inner skin facing, elongated, elastic bandage comprising: (i) an elongated, elastic substrate, and
(ii) an elongated layer of foam, said foam layer being affixed to a face of said substrate and extending <NUM>% or more across said face of substrate in transverse direction and <NUM>% or more across said face of substrate in longitudinal direction; and b) an outer, elongated, self-adhering elastic bandage; said bandage having a compressive force when extended; wherein, in use, said foam layer of the inner bandage faces the skin and the outer bandage overlies the inner bandage. A compression bandage of this type is disclosed in <CIT>.

Other compression bandage systems, such as those disclosed in <CIT> and <CIT>.

Treatment of such wounds can be performed using negative pressure wound therapy, wherein a reduced or negative pressure can be applied to the wound to facilitate and promote healing of the wound. It will also be appreciated that the wound dressing and methods as disclosed herein may be applied to other parts of the body, and are not necessarily limited to treatment of wounds.

It will be understood that aspects of the present disclosure are generally applicable to use in topical negative pressure ("TNP") therapy systems. Briefly, negative pressure wound therapy assists in the closure and healing of many forms of "hard to heal" wounds by reducing tissue oedema; encouraging blood flow and granular tissue formation; removing excess exudate and may reduce bacterial load (and thus infection risk). In addition, the therapy allows for less disturbance of a wound leading to more rapid healing. TNP therapy systems may also assist on the healing of surgically closed wounds by removing fluid and by helping to stabilize the tissue in the apposed position of closure. A further beneficial use of TNP therapy can be found in grafts and flaps where removal of excess fluid is important and close proximity of the graft to tissue is required in order to ensure tissue viability.

Negative pressure therapy can be used for the treatment of open or chronic wounds that are too large to spontaneously close or otherwise fail to heal by means of applying negative pressure to the site of the wound. Topical negative pressure (TNP) therapy or negative pressure wound therapy (NPWT) involves placing a cover that is impermeable or semi-permeable to fluids over the wound, using various means to seal the cover to the tissue of the patient surrounding the wound, and connecting a source of negative pressure (such as a vacuum pump) to the cover in a manner so that negative pressure is created and maintained under the cover. It is believed that such negative pressures promote wound healing by facilitating the formation of granulation tissue at the wound site and assisting the body's normal inflammatory process while simultaneously removing excess fluid, which may contain adverse cytokines or bacteria.

Some of the dressings used in NPWT can include many different types of materials and layers, for example, gauze, pads, foam pads or multi-layer wound dressings. One example of a multi-layer wound dressing is the PICO dressing, available from Smith & Nephew, includes a wound contact layer and a superabsorbent layer beneath a backing layer to provide a canister-less system for treating a wound with NPWT. The wound dressing may be sealed to a suction port providing connection to a length of tubing, which may be used to pump fluid out of the dressing or to transmit negative pressure from a pump to the wound dressing. Additionally, RENASYS-F, RENASYS-G, RENASYS-AB, and RENASYS-F/AB, available from Smith & Nephew, are additional examples of NPWT wound dressings and systems. Another example of a multi-layer wound dressing is the ALLEVYN Life dressing, available from Smith & Nephew, which includes a moist wound environment dressing that is used to treat the wound without the use of negative pressure.

As is used herein, reduced or negative pressure levels, such as -X mmHg, represent pressure levels relative to normal ambient atmospheric pressure, which can correspond to <NUM> mmHg (or <NUM> atm, <NUM> inHg, <NUM> kPa, <NUM> psi, etc.). Accordingly, a negative pressure value of -X mmHg reflects absolute pressure that is X mmHg below <NUM> mmHg or, in other words, an absolute pressure of (<NUM>-X) mmHg. In addition, negative pressure that is "less" or "smaller" than X mmHg corresponds to pressure that is closer to atmospheric pressure (such as,-<NUM> mmHg is less than -<NUM> mmHg). Negative pressure that is "more" or "greater" than -X mmHg corresponds to pressure that is further from atmospheric pressure (such as, -<NUM> mmHg is more than -<NUM> mmHg). Local ambient atmospheric pressure can be used as a reference point, and such local atmospheric pressure may not necessarily be, for example, <NUM> mmHg.

The negative pressure range for some aspects of the present disclosure can be approximately -<NUM> mmHg, or between about -<NUM> mmHg and -<NUM> mmHg. Note that these pressures are relative to normal ambient atmospheric pressure, which can be <NUM> mmHg. Thus, -<NUM> mmHg would be about <NUM> mmHg in practical terms. In some embodiments, the pressure range can be between about -<NUM> mmHg and -<NUM> mmHg. Alternatively a pressure range of up to -<NUM> mmHg, up to -<NUM> mmHg or over -<NUM> mmHg can be used. Also in other embodiments a pressure range of below -<NUM> mmHg can be used. Alternatively, a pressure range of over approximately -<NUM> mmHg, or even -<NUM> mmHg, can be supplied by the negative pressure apparatus.

In some aspects of wound closure devices described herein, increased wound contraction can lead to increased tissue expansion in the surrounding wound tissue. This effect may be increased by varying the force applied to the tissue, for example, by varying the negative pressure applied to the wound over time, possibly in conjunction with increased tensile forces applied to the wound. Negative pressure may be varied over time for example using a sinusoidal wave, square wave, or in synchronization with one or more patient physiological indices (such as, heartbeat). Examples of such applications where additional disclosure relating to the preceding may be found include <CIT>; and <CIT>.

The wound dressings, wound dressing components, wound treatment apparatuses and methods described herein may also be used in combination or in addition to those described in International Application No. <CIT>, published as <CIT>, titled "APPARATUSES AND METHODS FOR NEGATIVE PRESSURE WOUND THERAPY," <CIT>, published as <CIT>, titled "WOUND DRESSING AND METHOD OF TREATMENT," The wound dressings, wound dressing components, wound treatment apparatuses and methods described herein may also be used in combination or in addition to those described in <CIT>, published as <CIT>, titled "WOUND DRESSING AND METHOD OF USE," and <CIT>, published as <CIT>, titled "FLUIDIC CONNECTOR FOR NEGATIVE PRESSURE WOUND THERAPY," including further details relating to wound dressings, the wound dressing components and principles, and the materials used for the wound dressings.

Additionally, some aspects related to TNP wound treatment comprising a wound dressing in combination with a pump or associated electronics described herein may also be used in combination or in addition to those described in International Application <CIT>, published as <CIT>, entitled "REDUCED PRESSURE APPARATUS AND METHODS,".

A wound dressing that incorporates a number of sensors can be utilized in order to monitor characteristics of a wound as it heals. Collecting data from the wounds that heal well, and from those that do not, can provide useful insights towards identifying characteristics to indicate whether a wound may be on a healing trajectory.

In some implementations, a number of sensor technologies can be used in wound dressings or one or more components forming part of an overall wound dressing apparatus.

Optical sensors can be used to measure wound appearance using an RGB sensor with an illumination source. Both the RGB sensor and the illumination source would be pressed up against the skin, such that light would penetrate into the tissue and take on the spectral features of the tissue itself.

Light propagation in tissue can be dominated by two major phenomena, scattering and attenuation. For attenuation, as light passes through tissue, its intensity may be lost due to absorption by various components of the tissue. Blue light tends to be attenuated heavily, whilst light at the red end of the spectrum tends to be attenuated least.

Scattering processes can be more complex, and can have various "regimes" which must be considered. The first aspect of scattering is based on the size of the scattering center compared with the wavelength of incident light. If the scattering center is much smaller than the wavelength of light, then Rayleigh scattering can be assumed. If the scattering center is on the order of the wavelength of light, then a more detailed Mie scattering formulation may be considered. Another factor involved in scattering light is the distance between input and output of the scattering media. If a mean free path of the light (the distance between scattering events) is much larger than the distance travelled, then ballistic photon transport may be assumed. In the case of tissue, scatting events are approximately <NUM> microns apart - so a <NUM> path distance would effectively randomize the photon direction and the system would enter a diffusive regime.

Ultra bright LEDs, an RGB sensor, and polyester optical filters can be used as components of the optical sensors to measure through tissue color differentiation. For example, because surface color can be measured from reflected light, a color can be measured from light which has passed through the tissue first for a given geometry. This can include color sensing from diffuse scattered light, from a LED in contact with the skin. A LED can be used with an RGB sensor nearby to detect the light which has diffused through the tissue. The optical sensors can image with diffuse internal light or surface reflected light.

Additionally, the optical sensors can be used to measure autofluorescence. Autoflourescense is used because the tissue is absorbing light at one wavelength, and emitting at another. Additionally, dead tissue may not auto-fluoresce and so this could be a very strong indication as to if the tissue is healthy or not. Due to blue light (or even ultraviolet light) having such a short penetration depth, it may be very useful for example to have a ultraviolet light with a red sensitive photodiode nearby (or some other wavelength shifted band) to act as a binary test for healthy tissue, which would auto-fluoresce at a very particular wavelength.

<FIG> illustrates a negative or reduced pressure wound treatment (or TNP) system <NUM> comprising a wound filler <NUM> placed inside a wound cavity <NUM>, the wound cavity sealed by a wound cover <NUM>. The wound filler <NUM> in combination with the wound cover <NUM> can be referred to as a wound dressing. A single or multi lumen tube or conduit <NUM> is connected the wound cover <NUM> with a pump assembly <NUM> configured to supply reduced pressure. The wound cover <NUM> can be in fluidic communication with the wound cavity <NUM>. A sensing element <NUM> (for example, a sensor or a sensing material like a mechanochromic material, a thermochromic material, or a pH sensitive material) can be proximate to, attached to, or incorporated in the wound cavity <NUM>, the wound cover <NUM>, the wound filler <NUM>, or the conduit <NUM> and be used, for instance, to monitor the wound cavity <NUM> as described herein.

As illustrated in <FIG>, the pump assembly <NUM> can be a canisterless pump assembly (meaning that exudate is collected in the wound dressing or is transferred via conduit <NUM> for collection to another location). However, any of the pump assemblies disclosed herein can be configured to include or support a canister. Additionally, any of the pump assemblies can be mounted to or supported by the dressing, or adjacent to the dressing.

The wound filler <NUM> can be any suitable type, such as hydrophilic or hydrophobic foam, gauze, inflatable bag, and so on. The wound filler <NUM> can be conformable to the wound cavity <NUM> such that it substantially fills the cavity. The wound cover <NUM> can provide a substantially fluid impermeable seal over the wound cavity <NUM>. The wound cover <NUM> can have a top side and a bottom side, and the bottom side adhesively (or in any other suitable manner) seals with wound cavity <NUM>. The conduit <NUM> or lumen or any other conduit or lumen disclosed herein can be formed from polyurethane, PVC, nylon, polyethylene, silicone, or any other suitable material.

The wound cover <NUM> can have a port (not shown) configured to receive an end of the conduit <NUM>. For example, the port can be Renays Soft Port available from Smith & Nephew. Additionally or alternatively, the conduit <NUM> can pass through or under the wound cover <NUM> to supply reduced pressure to the wound cavity <NUM> so as to maintain a desired level of reduced pressure in the wound cavity. The conduit <NUM> can be any suitable article configured to provide at least a substantially sealed fluid flow pathway between the pump assembly <NUM> and the wound cover <NUM>, so as to supply the reduced pressure provided by the pump assembly <NUM> to wound cavity <NUM>.

The wound cover <NUM> and the wound filler <NUM> can be provided as a single article or an integrated single unit. In some implementations, no wound filler is provided and the wound cover by itself may be considered the wound dressing. The wound dressing may then be connected, via the conduit <NUM>, to a source of negative pressure, such as the pump assembly <NUM>. The pump assembly <NUM> can be miniaturized and portable, although larger conventional pumps such can also be used.

The wound cover <NUM> can be located over a wound site to be treated. The wound cover <NUM> can form a substantially sealed cavity or enclosure over the wound site. The wound cover <NUM> can be configured to have a film having a high water vapour permeability to enable the evaporation of surplus fluid, and can have a superabsorbing material contained therein to safely absorb wound exudate. It will be appreciated that throughout this specification reference is made to a wound. In this sense it is to be understood that the term wound is to be broadly construed and encompasses open and closed wounds in which skin is torn, cut or punctured or where trauma causes a contusion, or any other surficial or other conditions or imperfections on the skin of a patient or otherwise that benefit from reduced pressure treatment. A wound is thus broadly defined as any damaged region of tissue where fluid may or may not be produced. Examples of such wounds include, but are not limited to, acute wounds, chronic wounds, surgical incisions and other incisions, subacute and dehisced wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure ulcers, stoma, surgical wounds, trauma and venous ulcers or the like. The components of the TNP system described herein can be particularly suited for incisional wounds that exude a small amount of wound exudate.

Some implementations of the system are designed to operate without the use of an exudate canister. Some implementations can be configured to support an exudate canister. Configuring the pump assembly <NUM> and conduit <NUM> so that the conduit <NUM> can be quickly and easily removed from the pump assembly <NUM> can facilitate or improve the process of dressing or pump changes, if necessary. Any of the pumps disclosed herein can be configured to have any suitable connection between the tubing and the pump.

The pump assembly <NUM> can be configured to deliver negative pressure of approximately -<NUM> mmHg, or between about -<NUM> mmHg and <NUM> mmHg in some implementations. Note that these pressures are relative to normal ambient atmospheric pressure thus, -<NUM> mmHg would be about <NUM> mmHg in practical terms. The pressure range can be between about -<NUM> mmHg and -<NUM> mmHg. Alternatively a pressure range of up to - <NUM> mmHg, up to -<NUM> mmHg or over -<NUM> mmHg can be used. Also a pressure range of below - <NUM> mmHg can be used. Alternatively a pressure range of over approximately -<NUM> mmHg, or even <NUM> mmHg, can be supplied by the pump assembly <NUM>.

In operation, the wound filler <NUM> is inserted into the wound cavity <NUM> and wound cover <NUM> is placed so as to seal the wound cavity <NUM>. The pump assembly <NUM> provides a source of a negative pressure to the wound cover <NUM>, which is transmitted to the wound cavity <NUM> via the wound filler <NUM>. Fluid (such as, wound exudate) is drawn through the conduit <NUM>, and can be stored in a canister. Fluid can be absorbed by the wound filler <NUM> or one or more absorbent layers (not shown).

Wound dressings that may be utilized with the pump assembly and other aspects of the present application include Renasys-F, Renasys-G, Renasys AB, and Pico Dressings available from Smith & Nephew. Further description of such wound dressings and other components of a negative pressure wound therapy system that may be used with the pump assembly and other aspects of the present application are found in <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>. Other suitable wound dressings can be utilized.

<FIG> illustrates an electrical component schematic of a pump assembly <NUM>. Electrical components can operate to accept user input, provide output to the user, operate the pump assembly and the TNP system, provide network connectivity, and so on. Electrical components can be mounted on one or more printed circuit boards (PCBs) that mechanically support and electrically connect electronic components using conductive tracks, pads and other features etched from copper sheets laminated onto a non-conductive substrate. Components, such as capacitors, resistors, or active devices, can be soldered on the PCBs or embedded in the substrate. As is illustrated, the pump assembly can include multiple processors.

The pump assembly can include a user interface controller or processor <NUM> that can function as a main processor and be configured to operate one or more components for accepting user input and providing output to the user, such as a display, buttons, etc. Input to the pump assembly and output from the pump assembly can controlled by an input/output (I/O) module <NUM>. For example, the I/O module can receive data from one or more ports, such as serial, parallel, hybrid ports, and the like. The processor <NUM> also receives data from and provides data to one or more expansion modules <NUM>, such as one or more USB ports, SD ports, CD drives, DVD drives, FireWire ports, Thunderbolt ports, PCI Express ports, and the like. The processor <NUM>, along with other controllers or processors, stores data in memory <NUM>, which can be one or more memory modules and be internal or external to the processor <NUM>. Any suitable type of memory can be used, including volatile or non-volatile memory, such as RAM, ROM, magnetic memory, solid-state memory, magnetoresistive random-access memory (MRAM), and the like.

The processor <NUM> can be a general purpose controller, such as a low-power processor. The processor <NUM> can be an application specific processor. The processor <NUM> can be configured as a "central" processor in the electronic architecture of the pump assembly, and the processor <NUM> can coordinate the activity of other processors, such as a pump control processor <NUM>, communications processor <NUM>, and one or more additional processors <NUM> (e.g., processor for controlling the display <NUM>, processor for controlling the buttons <NUM>, etc.). The processor <NUM> can run a suitable operating system, such as a Linux, Windows CE, VxWorks, etc..

The pump control processor <NUM> can be configured to control the operation of a pump <NUM>, such as a negative pressure pump. The pump <NUM> can be a suitable pump, such as a diaphragm pump, peristaltic pump, rotary pump, rotary vane pump, scroll pump, screw pump, liquid ring pump, diaphragm pump operated by a piezoelectric transducer, voice coil pump, and the like. The pump control processor <NUM> can measure pressure in a fluid flow path, using data received from one or more pressure sensors, calculate the rate of fluid flow, and control the pump. The pump control processor <NUM> can control a pump motor so that a desired level of negative pressure is achieved in the wound cavity <NUM>. The desired level of negative pressure can be pressure set or selected by the user. The pump control processor <NUM> controls the pump (e.g., pump motor) using pulse-width modulation (PWM). A control signal for driving the pump can be a <NUM>-<NUM>% duty cycle PWM signal. The pump control processor <NUM> can perform flow rate calculations and detect various conditions in a flow path. The pump control processor <NUM> can communicate information to the processor <NUM>. The pump control processor <NUM> can include internal memory or can utilize memory <NUM>. The pump control processor <NUM> can be a low-power processor.

A communications processor <NUM> can be configured to provide wired or wireless connectivity. The communications processor <NUM> can utilize one or more antennas <NUM> for sending and receiving data. The communications processor <NUM> can provide one or more of the following types of connections: Global Positioning System (GPS) technology, cellular connectivity (e.g., <NUM>, <NUM>, LTE, <NUM>), WiFi connectivity, Internet connectivity, and the like. Connectivity can be used for various activities, such as pump assembly location tracking, asset tracking, compliance monitoring, remote selection, uploading of logs, alarms, and other operational data, and adjustment of therapy settings, upgrading of software or firmware, and the like. The communications processor <NUM> can provide dual GPS/cellular functionality. Cellular functionality can, for example, be <NUM> functionality. The pump assembly can include a SIM card, and SIM-based positional information can be obtained.

The communications processor <NUM> can also be electrically coupled to one or more one or more serial, parallel, or hybrid data transfer connector interfaces through which the communications processor <NUM> can directly receive data or commands without receiving the data or commands through or from the processor <NUM>. For instance, the data transfer connector interfaces can include one or more USB ports, SD ports, CD drives, DVD drives, FireWire ports, Thunderbolt ports, PCI Express ports, and the like.

The communications processor <NUM> can communicate information to the processor <NUM> and receive information from the processor <NUM>. The communications processor <NUM> can include internal memory or can utilize memory <NUM>. The communications processor <NUM> can be a low-power processor.

Using the connectivity provided by the communications processor <NUM>, the device can upload any of the data stored, maintained, or tracked by the pump assembly. The device can also download various operational data, such as therapy selection and parameters, firmware and software patches and upgrades, and the like.

An optical processor <NUM> can process optical signals generated by a detector to determine a measurement value indicative of wound characteristics (e.g., temperature, pressure, or exudate features). The optical processor <NUM> can be communicatively coupled with an emitter for emitting electromagnetic radiation and the detector for sensing electromagnetic radiation. The optical processor <NUM> can control the emission of electromagnetic radiation with the emitter. Further, the optical processor <NUM> can process the optical signals generated by the detector and output characteristics of a wound based on the information determined from the optical signals. The optical processor <NUM> can include internal memory (not shown) or can utilize memory <NUM>. The optical processor <NUM> can access the internal memory or the memory <NUM> in forming associations between data received from the detector and wound characteristics. The optical processor <NUM> can communicate information, such as measurement values or other determined information, to the processor <NUM>.

<FIG> illustrates the wound treatment apparatus <NUM> including one or more optical fibers. The wound treatment apparatus <NUM> can include a wound dressing <NUM> configured to be positioned proximate to a wound. Multiple optical fibers can be positioned at least partly in the wound dressing <NUM>. An emitter <NUM> can emit electromagnetic radiation into an emitting optical fiber <NUM> such that the electromagnetic radiation travels through the emitting optical fiber <NUM>. A detector <NUM> can generate a signal responsive to reflected electromagnetic radiation captured by detecting optical fiber <NUM> and that contacts the detector <NUM>. Optical fibers can run outside of the wound dressing <NUM> and then pierce into the wound dressing <NUM> (e.g., through-plane) to transmit or receive electromagnetic radiation at locations as illustrated by <FIG>. The optical fibers described herein can be constructed of polymeric material, glass, or quartz.

An emitting optical fiber <NUM> can be positioned substantially outside the wound dressing <NUM>. A first end of the emitting optical fiber <NUM> can be connected to an emitter <NUM>, such as a LED or any other optoelectronic source including, OLED, photodiodes, laser diodes etc. The emitter <NUM> can be a single source or a multisource emitter with multiple emitters or multiple optical fibers. A second end of the emitting optical fiber <NUM> can penetrate through the wound dressing <NUM> such that electromagnetic radiation can travel from the emitter <NUM> through the emitting optical fiber <NUM> and onto the wound.

The wound treatment apparatus <NUM> can further include a detecting optical fiber <NUM>. A first end of the detecting optical fiber <NUM> can be attached to a detector <NUM>, such as a sensor capable of detecting electromagnetic radiation. The detector <NUM> can include of a wide variety of sensors, such as photo-resistors, or Light Dependent Resistors (LDR), that changes resistance according to light intensity, photodiodes, charge coupled devices (CCD) or other light sensors. It is also possible to integrate miniaturized sensing elements on the micro-scale to nano-scale order at or within the tip of the fiber, though this may negate the advantage of non-localized electronics discussed in this disclosure. The detector <NUM> can include a single receiving sensor or multiple receiving sensors. A second end of the detecting optical fiber <NUM> can penetrate through the wound dressing <NUM> such that the electromagnetic radiation that exited the emitting optical fiber <NUM> and is reflected off of the wound can enter the detecting optical fiber <NUM> where it is transmitted to the detector <NUM>. It should be noted that a single optical fiber can be used to both or either emit and detect electromagnetic radiation.

As illustrated in <FIG>, the emitter <NUM> and the detector <NUM> can advantageously, in certain implementations, be positioned away from the wound dressing. Thus, sensitive electronics can be kept at a safe distance while still being able to function appropriately via the optical fibers. Electronic and conductive elements can be kept away from the vicinity of the wound and improve electrical isolation for the patient.

The detector <NUM> can detect the reflected electromagnetic radiation and generate a signal responsive to the reflected electromagnetic radiation, which can then be processed by the optical processor <NUM>. The reflected electromagnetic radiation can include a portion of the emitted electromagnetic radiation that was reflected off of the wound.

The signal output from the detector <NUM> can be used to determine a measurement value indicative of wound characteristics (e.g., temperature, pressure, or exudate features). Direct optical measurement/observation of the wound or local tissue may be possible. Temperature identification can be detected by color changing thermochromic material. The wound treatment apparatus <NUM> can detect the temperature based on the detected electromagnetic radiation using optical thermometers. The absence of negative pressure can be identified based on the presence or absence of total internal reflection within an optical fiber. Some implementations can implement multiplexing techniques where the light source is polarized for sectionable area interrogation. For instance, half of a wound or wound dressing can be investigated via polarized light in one direction opposite to the other side, such that two direct streams of light are measured. This method may be extended to multiple color streams via color filtration in some implementations.

Optical measurements can be taken of the pH levels by color changing pH sensitive materials such as dyes or gels. Such pH sensitive materials may be encapsulated within the dressing.

Moreover, reduced pressure can be supplied to the wound dressing <NUM> based on the measurement values indicative of the wound characteristics. Additionally, the notifications can be provided to user equipment (for instance, by activation of an indicator, such as to provide notice of detection of an excess of exudate) based on the measurement values indicative of the wound characteristics. Updates can be provided on the status of a wound, for instance, color, temperature, or other characteristics that can be used to gain understanding of the healing process based on the measurement values indicative of the wound characteristics.

<FIG> illustrates a through-plane example path for electromagnetic radiation through a wound dressing <NUM>, which can be similar to or the same as the wound dressing <NUM>. An emitter <NUM> and a detector <NUM> can be positioned on or within a non-sterile portion of the wound dressing <NUM>. As illustrated, the emitter <NUM> can transmit electromagnetic radiation, via an emitting optical fiber <NUM>, through a plane created by the wound dressing <NUM> (e.g., orthogonal to a direction that the wound dressing <NUM> extends over a wound). Similarly, the detector <NUM> can positioned on or within a non-sterile portion of the wound dressing <NUM> such that the detector <NUM> can receive, via a detecting optical fiber <NUM>, reflected electromagnetic radiation along a path that is perpendicular to the plane created by the wound dressing <NUM>.

<FIG> illustrates a wound dressing <NUM> that has a tri-laminate configuration with positions for optical fibers. The wound dressing <NUM> can include an emitting position <NUM> for the passage of an emitting optical fiber into the wound dressing <NUM>. The wound dressing <NUM> can include a detecting position <NUM> configured to allow passage of a detecting optical fiber.

Both an emitting optical fiber and a detecting optical fiber can utilize the same opening in the wound dressing <NUM> in some implementations. Additionally, it will be understood that although one emitting position <NUM> and one detecting position <NUM> are illustrated, there may be multiple positions to match multiple optical fibers. As discussed in greater detail herein, the detecting position <NUM> and the emitting position <NUM> can be located relative to one another so as to maximize an amount electromagnetic radiation being reflected into one or more detecting optical fibers.

The wound dressing <NUM> can include a wound filler and a wound cover, such that the optical fibers extend through the wound filler and the wound cover. As illustrated in <FIG>, a tri-laminate dressing can consist of a perforated wound contact layer <NUM>, a polyurethane absorbent core <NUM>, and a breathable bacterial barrier top film <NUM>. A sensor layer can be incorporated in multiple locations in this construct; (e.g., above the top film <NUM>, replacing the top film <NUM>, between the top film <NUM> and polyurethane absorbent core <NUM>, between the polyurethane absorbent core <NUM> and the wound contact layer <NUM>, and replacing the wound contact layer <NUM>). Additionally, a bi-laminate dressing can be formed, wherein a cushioning or protective layer may be placed between the sensor sheet and the wound. This can allow even topography to avoid pressure points within the sensory architecture. The sensor layer can be at least partly manufactured from conductive printed materials to maintain a low-profile architecture.

<FIG> illustrates an example in-plane path for optical fibers through a wound dressing <NUM>, which can be similar to or the same as the wound dressing <NUM>. As illustrated, an emitting optical fiber <NUM> and a detecting optical fiber <NUM> can run within the wound dressing <NUM> itself and extend in a direction in which the wound dressing <NUM> extends over a wound. The emitting optical fiber <NUM> and the detecting optical fiber <NUM> can then exit the wound dressing <NUM> to emit and detect electromagnetic radiation onto and from the wound bed. After exiting the wound dressing <NUM>, the emitting optical fiber <NUM> and the detecting optical fiber <NUM> can continue to run between the wound dressing <NUM> and the wound, parallel to the wound dressing <NUM>. An emitter <NUM> can be used to emit electromagnetic radiation, and a detector <NUM> can be used to detect electromagnetic radiation.

<FIG> illustrate examples of notched or slotted optical fibers that can integrated with a wound dressing, such as the wound dressing <NUM>, or used in combination with the wound dressing. For instance, <FIG> illustrates the an optical fiber <NUM> with multiple slots <NUM> (or notches) located along a length of the optical fiber <NUM> positioned parallel to a wound. The slots <NUM> can allow electromagnetic radiation to escape or enter the optical fiber <NUM> at slot locations, such as along a wound bed. In such a manner, electromagnetic radiation can exit or enter the optical fiber <NUM> at a number of locations rather than just at an end of the optical fiber <NUM>. Moreover, the slots <NUM> can be positioned so that particular slots emit electromagnetic radiation of certain wavelength or wavelengths but not at another wavelength or wavelengths.

The optical fiber <NUM> can run partly or completely within or substantially parallel to a wound dressing. Electromagnetic radiation can then be emitted or detected by indexed punching of a wound contact layer, such as the wound contact layer <NUM>, to generate optical pathways. The indexed punching can align with the slots <NUM>. The optical fiber <NUM> can be notched or slotted by physical punch, laser, or other methods. <FIG> illustrates another example of a slot <NUM> (or a notch) in the an optical fiber <NUM>. It should be understood that the above discussion of slots can apply to both the emitting optical fibers for emitting electromagnetic radiation at various points and the detecting optical fibers for detecting electromagnetic radiation at various points.

<FIG> illustrates an example where an optical fiber <NUM> runs parallel to a wound dressing <NUM>. The optical fiber <NUM> includes three slots <NUM> where electromagnetic radiation is released from the optical fiber <NUM> at three locations. In some implementations, the optical fiber <NUM> may not be notched, but instead includes portions where the material of the optical fiber <NUM> has an appropriate refractive index to allow the electromagnetic radiation to be directed onto a wound.

<FIG> illustrates an emitting optical fiber <NUM> with a slot <NUM>. An adhesive contact <NUM> can be positioned on the emitting optical fiber <NUM> and allow electromagnetic radiation to travel to a wound a defined locations. The adhesive contact <NUM> can hold the emitting optical fiber <NUM> in place to ensure the electromagnetic radiation continues to exit the emitting optical fiber <NUM> at the proper locations. An adhesive contact can also be used to hold a detecting optical fiber in a fixed location with respect to a wound or a wound dressing.

A wound dressing can be constructed to allow contact of an optical fiber with a construction adhesive above a transparent wound contact layer, allowing electromagnetic radiation to be transmitted to the wound, whilst encapsulating the optical fiber within the wound dressing.

<FIG> illustrates an optical fiber <NUM> with a truncated end <NUM>. The truncated end <NUM> can be truncated at a particular angle and thereby cause electromagnetic radiation to exit or enter the optical fiber <NUM> at various angles. For instance, the truncated end <NUM> can allow electromagnetic radiation exiting the optical fiber <NUM> to be incident on a wound or entering the optical fiber <NUM> to enter without having an end of the optical fiber <NUM> face toward the wound, such as is shown in <FIG>. Further, the truncated end <NUM> can allow electromagnetic radiation exiting the optical fiber <NUM> to scatter. When the optical fiber <NUM> serves as a detecting optical fiber, an end of optical fiber <NUM> can be truncated at an angle so that reflected electromagnetic radiation may, for instance, more likely to enter at the end.

<FIG> illustrate various example configurations of optical fibers. The optical fibers can be angled at the ends in order to emit or detect electromagnetic radiation at predetermined locations. For example, the optical fibers can be angled approximately <NUM> degrees such that the optical fibers transition from substantially parallel to a wound dressing <NUM> to substantially perpendicular to the wound dressing <NUM>. There may be a single emitting optical fiber <NUM> surrounded by multiple detecting optical fibers <NUM>. As illustrated in <FIG>, there are a number of possible configurations and layouts for the optical fibers. For instance, <FIG> illustrates a configuration with alternating emitting optical fibers <NUM> and detecting optical fibers <NUM>. <FIG> illustrates a configuration in which a single emitting optical fiber <NUM> in the center of four detecting optical fibers <NUM>, and the detecting optical fibers <NUM> form a square pattern around the emitting optical fiber <NUM>. Likewise, <FIG> illustrates a configuration in which a single emitting optical fiber <NUM> is surrounded by detecting optical fibers <NUM>, and the detecting optical fibers <NUM> form a hexagon pattern around the emitting optical fiber <NUM>. The various configurations that can be selected for particular wound sizes, wound shapes, or wound dressings, for instance, to maximize an amount of reflected electromagnetic radiation that the detecting optical fibers <NUM> detect.

<FIG> illustrates a wound dressing <NUM> with multiple emitting optical fibers and a detecting optical fiber. The multiple emitting optical fibers can be coupled to one or more emitters <NUM>. The detecting optical fiber can be coupled to a detector <NUM> that detects electromagnetic radiation passing through the detecting optical fiber. As can be seen from <FIG>, the illustrated configuration may be used to transmit and reflect electromagnetic radiation at different depths in a wound area to determine wound characteristics at the different depths.

<FIG> illustrates an emitter <NUM> and a detector <NUM> being used to detect liquid <NUM>, such as wound exudate. As is discussed herein, a wound dressing can be constructed to allow emitting and detecting optical fibers to pass and detect electromagnetic radiation under the wound dressing. The electromagnetic radiation can be used, for instance, to detect wound exudate that may be accumulating under or within the wound dressing. The optical fibers can, for example, be within the wound dressing and detect when wound exudate enters the wound dressing from a variation in the electromagnetic radiation (for instance, a change in light intensity) detected by the detector <NUM>.

<FIG> illustrates optical fibers <NUM> in a grid configuration, with emitting optical figures being illuminated by emitters λ, and detecting optical fibers detecting with detectors S. The optical fibers <NUM> can be arranged in a grid pattern or a zig zag to locate a position or extent of wound exudate across a wound dressing. Such a configuration can be used to determine how saturated the wound dressing may be and thus to indicate an appropriate time for changing the wound dressing.

One or more electronic components can be positioned on or around a wound dressing that incorporates one or more optical fibers. For example, the one or more electronic components can be on the side of a wound contact layer opposite the side that faces the wound.

Although certain examples herein are described in the context of wound dressings, the features disclosed herein can apply to other objects or materials. For example, optical fibers can pass through fabrics, garments, shielding, or other barriers to permit electromagnetic radiation to enter or exit the optical fibers for enabling monitoring through the fabrics, garments, shielding, or other barriers.

Features, materials, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features or steps are mutually exclusive. The protection is not restricted to the details of any foregoing embodiments. The protection extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of protection. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made. Those skilled in the art will appreciate that in some embodiments, the actual steps taken in the processes illustrated or disclosed may differ from those shown in the figures. For example, the actual steps or order of steps taken in the disclosed processes may differ from those shown in the figure. For instance, the various components illustrated in the figures may be implemented as software or firmware on a processor, controller, ASIC, FPGA, or dedicated hardware. Hardware components, such as controllers, processors, ASICs, FPGAs, and the like, can include logic circuitry.

Although the present disclosure includes certain embodiments, examples and applications, it will be understood by those skilled in the art that the present disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments or uses and obvious modifications and equivalents thereof, including embodiments which do not provide all of the features and advantages set forth herein. Accordingly, the scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments herein, and may be defined by claims as presented herein or as presented in the future.

Claim 1:
A negative pressure wound treatment apparatus comprising:
a wound dressing (<NUM>) configured to be positioned proximate to a wound;
a pressure source being configured to provide negative pressure to the wound;
a plurality of optical fibers positioned at least partly in the wound dressing, the plurality of optical fibers comprising a first optical fiber and a second optical fiber;
an emitter (<NUM>) configured to emit first electromagnetic radiation into the first optical fiber, the first optical fiber being configured to pass the first electromagnetic radiation;
a detector (<NUM>) configured to generate a signal responsive to second electromagnetic radiation exiting the second optical fiber and contacting the detector; and
a processor (<NUM>) configured to determine a measurement value from the signal, the measurement value being indicative of a pressure at the wound, wherein the processor is configured to control the pressure source responsive to the measurement value.