Negative pressure wound therapy system using Euler video zoom

Abstract

Embodiments of tissue monitoring combined with negative pressure wound therapy systems and methods are disclosed. In some embodiments, the monitoring and treatment system includes acquiring video images of a tissue site and amplifying the video images by Euler video amplification. Depending on changes detected by Euler video amplification, negative pressure wound therapy can be delivered to the tissue site, stopped, or altered in some manner.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 506,524, filed May 15, 2017, the disclosure of which is incorporated herein by reference in its entirety. background Technical Field

[0004] Embodiments described herein relate to devices, systems, and methods for treating wounds using dressings, for example, in combination with wound monitoring and negative pressure wound therapy. Background Art

[0006] Treating open or chronic wounds that are too large to close spontaneously or otherwise fail to heal by applying negative pressure to the wound site is well known in the art. Negative pressure wound therapy (NPWT) systems currently known in the art generally involve placing a fluid-impermeable or semi-permeable cover over the wound, using various means to seal the cover to the patient's tissue surrounding the wound, and connecting a negative pressure source (such as a vacuum pump) to the cover in a manner that generates and maintains negative pressure beneath the cover. It is believed that such negative pressure promotes wound healing by promoting the formation of granulation tissue at the wound site and aiding the body's normal inflammatory process while removing excess fluid that may contain adverse cytokines and / or bacteria. However, further improvements in NPWT are needed to fully realize the therapeutic benefits.

[0007] Many different types of wound dressings are known for use in assisting NPWT systems. 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. One example of a multi-layer wound dressing is the PICO dressing available from Smith & Nephew, which includes a wound contact layer and a superabsorbent layer beneath a backing layer to provide a canisterless system for treating wounds with NPWT. The wound dressing may be sealed to a suction port that provides a connection to a length of tubing that can be used to pump fluid out of the dressing and / or transmit negative pressure from a pump to the wound dressing. Additionally, the 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 ALLEVYNLife dressing available from Smith & Nephew, which includes a wet wound environment dressing for treating wounds without the use of negative pressure.

[0008] However, prior art dressings for negative pressure wound therapy or other wound therapies provide little visualization or information about the status of the wound site beneath the dressing. This may require premature dressing changes before the desired level of wound healing has occurred, or, for absorbent dressings, before the full absorptive capacity of the dressing is reached to allow the clinician to inspect the healing and status of the wound. Some current dressings have limited and / or unsatisfactory methods or features for providing wound status information.

[0009] Furthermore, prior art techniques may provide insufficient information about the state of tissue before a wound exists (eg, before a pressure sore forms). Thus, there is a need for improved methods and techniques for assessing / detecting changes within wounds and tissues. Summary of the invention

[0010] Certain disclosed embodiments relate to devices, methods, and systems for monitoring tissue. It should be understood by those skilled in the art that the applications of the devices, methods, and systems described herein are not limited to specific tissues or specific injuries.

[0011] In some embodiments, a wound treatment system comprises: a negative pressure source configured to be in fluid communication with a wound dressing placed above a wound, the negative pressure source configured to provide negative pressure under the wound dressing; a visualization sensor located above the wound, the visualization sensor configured to capture video data of the wound; and a controller communicating with both the negative pressure source and the visualization sensor, the controller configured to: determine a processing factor from the video data, and if the processing factor is different from a threshold, cause the negative pressure source to increase or decrease the level of negative pressure provided.

[0012] In some embodiments, the controller may also be configured to amplify the video data by Euler video amplification. The processing factor may be determined from the difference between the regional values ​​measured in the video data. The video data may include RGB color data. The visualization sensor may be configured to wirelessly communicate with the controller. The controller may be configured to wirelessly communicate with the negative pressure source. The controller may be configured to transmit a signal to the negative pressure source to increase the negative pressure if the processing parameter is below a desired value. The controller may be configured to cause the negative pressure source to reduce the level of negative pressure provided if the processing parameter is above the threshold. The controller may be configured to compare the processing parameter with a plurality of thresholds. The controller may be configured to perform the comparison using a lookup table. The processing parameter may indicate blood flow in the wound. The threshold may correspond to a desired blood flow level in the wound.

[0013] Other embodiments are described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A reduced pressure wound treatment system is illustrated in accordance with some embodiments.

[0015] Figure 2A , Figure 2B and Figure 2C A pump assembly and canister are illustrated according to some embodiments.

[0016] Figure 3A A schematic diagram of the electrical components of a pump assembly according to some embodiments is illustrated.

[0017] Figure 3B A block diagram of components of a pump assembly according to some embodiments is illustrated.

[0018] Figure 4 A process for providing negative pressure wound therapy according to some embodiments is illustrated.

[0019] Figure 5A An embodiment of a negative pressure wound therapy system utilizing a flexible fluid connector and a wound dressing capable of absorbing and storing wound exudate is illustrated.

[0020] Figure 5B An embodiment of a negative pressure wound therapy system utilizing a flexible fluid connector and a wound dressing capable of absorbing and storing wound exudate is illustrated.

[0021] Fig. 6A An embodiment of a negative pressure wound therapy system utilizing a flexible fluid connector and a wound dressing capable of absorbing and storing wound exudate is illustrated.

[0022] Figure 6B A cross-section of an embodiment of a fluid connector connected to a wound dressing is illustrated.

[0023] Figure 7 An embodiment of a negative pressure wound therapy system is illustrated.

[0024] Figure 8 An embodiment of a process for video upscaling referred to as Euler video upscaling is illustrated.

[0025] Fig. 9 An embodiment of a wound treatment system is illustrated.

[0026] Fig. 10A An embodiment of a process for providing NPWT therapy is illustrated.

[0027] Fig. 10B An embodiment of a sampling method for sampling frames from a video is illustrated.

[0028] Fig.11A Is using PICO TMExample of a process lookup table for a pump.

[0029] Fig. 11B Using RENASYS TM Example of a process lookup table for a pump. DETAILED DESCRIPTION

[0030] Embodiments disclosed herein relate to devices and methods for monitoring and treating biological tissues with sensor-enabled substrates. Embodiments disclosed herein are not limited to treating or monitoring a particular type of tissue or wound, in fact, the sensor-enabled technology disclosed herein is broadly applicable to any type of treatment that can benefit from a sensor-enabled substrate. Some embodiments utilize sensors and data acquisition that healthcare providers rely on to make diagnoses and make patient management decisions.

[0031] Some embodiments disclosed herein relate to the use of sensors mounted on or embedded in a substrate, and the substrate is configured to process complete and damaged human or animal tissues. Such sensors can collect information about surrounding tissues, and such information is transmitted to a computing device or a caregiver to be used for further processing. In certain embodiments, these sensors can be attached to the skin anywhere on the body, including monitoring arthritis, temperature, or other areas that may be prone to problems and need to be monitored. Sensors disclosed herein can also be incorporated into markings, such as radiopaque markings, to indicate the presence of a device, such as before performing MRI or other techniques.

[0032] The sensor embodiments disclosed herein may be used in conjunction with clothing. Non-limiting examples of clothing used with the sensor embodiments disclosed herein include shirts, pants, trousers, skirts, underwear, outerwear, gloves, shoes, hats, and other suitable clothing. In certain embodiments, the sensor embodiments disclosed herein may be welded into or laminated into and / or onto specific clothing. The sensor embodiments may be printed directly onto clothing and / or embedded into fabrics. Breathable and printable materials, such as microporous films, may also be suitable.

[0033] The sensor embodiments disclosed herein can be incorporated into cushions or mattresses, such as within hospital beds, to monitor patient characteristics, such as any of the characteristics disclosed herein. In certain embodiments, a disposable membrane containing such sensors can be placed on a hospital bed and removed / replaced as needed.

[0034] In some implementations, the sensor embodiments disclosed herein may incorporate energy harvesting such that the sensor embodiments are self-sustaining. For example, energy may be harvested from a thermal energy source, a kinetic energy source, a chemical gradient, or any suitable energy source.

[0035] The sensor embodiments disclosed herein may be used in rehabilitation devices and treatments, including sports medicine. For example, the sensor embodiments disclosed herein may be used in brackets, sleeves, packaging materials, supports, and other suitable items. Similarly, the sensor embodiments disclosed herein may be incorporated into sports equipment, such as helmets, sleeves, and / or pads. For example, such sensor embodiments may be incorporated into protective helmets to monitor features such as acceleration, which may be used for concussion diagnosis.

[0036] The sensor embodiments disclosed herein may be used in conjunction with surgical devices (e.g., Smith & Nephew's NAVIO surgical system). In embodiments, the sensor embodiments disclosed herein may communicate with such surgical devices to guide placement of the surgical devices. In some embodiments, the sensor embodiments disclosed herein may monitor blood flow to or from a potential surgical site or ensure the absence of blood flow to a surgical site. Additional surgical data may be collected to help prevent scarring and monitor areas away from the affected area.

[0037] To further assist in surgical techniques, the sensors disclosed herein can be incorporated into surgical drapes to provide information about the tissue beneath the drape that may not be immediately visible to the naked eye. For example, a flexible drape embedded with sensors may have sensors that are advantageously positioned to provide improved area-centric data acquisition. In certain embodiments, the sensor embodiments disclosed herein can be incorporated into the borders or interior of a drape to create a fence to confine / control the operating room.

[0038] Sensor embodiments as disclosed herein may also be used for pre-surgical assessments. For example, such sensor embodiments may be used to collect information about potential surgical sites, such as by monitoring the skin and underlying tissue to find possible incision sites. For example, perfusion levels or other suitable features may be monitored at the skin surface 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 assess the presence of microbial infection and provide instructions for the use of antimicrobial agents. In addition, the sensor embodiments disclosed herein may collect further information in deeper tissues, such as identifying pressure sore lesions and / or adipose tissue levels.

[0039] Sensor embodiments disclosed herein may be used for 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 transmit this information to another device and / or a caregiver. For example, such a device may monitor pulse rate, blood oxygen, and / or electrical activity of the heart. Similarly, sensor embodiments disclosed herein may be used for neurophysiological applications, such as monitoring the electrical activity of neurons.

[0040] The sensor embodiments disclosed herein can be incorporated into implantable devices, such as implantable orthopedic implants, including flexible implants. Such sensor embodiments can be configured to collect information about the implant site and transmit the information to an external source. In some embodiments, the internal source can also provide power for this implant.

[0041] The sensor embodiments disclosed herein can also be used to monitor biochemical activity on or below the skin surface, such as lactose accumulation in muscle or sweat production on the skin surface. In some embodiments, other characteristics can be monitored, such as glucose concentration, urine concentration, tissue pressure, skin temperature, skin surface conductivity, skin surface resistivity, skin hydration, skin maceration, and / or skin cracking.

[0042] The sensor embodiments disclosed herein may be incorporated into ear, nose and throat (ENT) applications. For example, such sensor embodiments may be used to monitor recovery from ENT-related surgeries, such as wound monitoring within sinus tracts.

[0043] As described in more detail below, the sensor embodiments disclosed herein may encompass sensor printing techniques with encapsulation, such as encapsulation with polymer films. Such films may be constructed using any polymer described herein, such as polyurethane. The encapsulation of the sensor embodiments may provide waterproofing of the electronics and protection from local tissue, local fluids, and other potential sources of damage.

[0044] In certain embodiments, the sensors disclosed herein may be incorporated into an organ protection layer, as disclosed below. This sensor-embedded organ protection layer can protect the organ of interest and confirm that the organ protection layer is in place and provides protection. In addition, the sensor-embedded organ protection layer can be used to monitor the underlying organ, for example, by monitoring blood flow, oxygenation, and other suitable markers of organ health. In some embodiments, the sensor-enabled organ protection layer can be used to monitor transplanted organs, for example, by monitoring the fat and muscle content of the organ. In addition, the sensor-enabled organ protection layer can be used to monitor the organ during and after transplantation (e.g., during the recovery of the organ).

[0045] The sensor embodiments disclosed herein can be incorporated into wound treatment (disclosed in more detail below) or a variety of other applications. Non-limiting examples of additional applications of the sensor embodiments disclosed herein include: monitoring and treatment of intact skin; cardiovascular applications, such as monitoring blood flow; orthopedic applications, such as monitoring limb movement and bone repair; neurophysiological applications, such as monitoring electrical impulses; and any other tissue, organ, system, or situation that can benefit from improved sensor monitoring.

[0046] Wound treatment

[0047] Some embodiments disclosed herein relate to wound treatment for the human or animal body. Therefore, any reference to a wound herein may refer to a wound on the human or animal body, and any reference to the body herein may refer to the human or animal body. Embodiments of the disclosed technology may relate to preventing or minimizing damage to physiological tissue or living tissue, or to treating wounds of damaged tissue (e.g., wounds described herein) with or without reduced pressure, including, for example, negative pressure sources and wound dressing components and devices. Devices and components comprising wound covering and filling materials or internal layers (if present) are sometimes collectively referred to herein as dressings. In some embodiments, a wound dressing may be provided for use without reducing pressure.

[0048] Some embodiments disclosed herein relate to wound treatment for the human or animal body. Therefore, any reference to a wound herein may refer to a wound on the human or animal body, and any reference to a body herein may refer to the human or animal body. Embodiments of the disclosed technology may relate to preventing or minimizing damage to physiological or living tissue, or to the treatment of damaged tissue (e.g., a wound described herein).

[0049] As used herein, the expression "wound" may include damage to living tissue that may be caused by cutting, blows or other impacts, usually skin being cut or broken. Wounds may be chronic or acute injuries. Acute wounds occur due to surgery or trauma. They undergo various healing stages within a predicted time frame. Chronic wounds usually begin as acute wounds. When acute wounds do not follow the healing stages, acute wounds may become chronic wounds, thereby prolonging recovery time. The transition from acute wounds to chronic wounds is believed to be caused by impaired immunity of the patient.

[0050] Chronic wounds may include, for example: venous ulcers (such as those occurring in the legs), which account for the majority of chronic wounds and primarily affect the elderly; diabetic ulcers (e.g., foot or ankle ulcers); peripheral arterial disease; pressure sores or epidermolysis bullosa (EB).

[0051] Examples of other wounds include, but are not limited to, abdominal wounds or other large or open wounds resulting from surgery, trauma, sternotomy, fasciotomy, or other conditions, dehisced wounds, acute wounds, chronic wounds, subacute and dehisced wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure sores, ostomies, surgical wounds, traumatic ulcers, and venous ulcers.

[0052] Wounds may also include 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 sores. For years clinicians have described these sores using terms such as purple pressure sores, ulcers that may ulcerate and bruise over bony prominences.

[0053] Wounds may also include tissue that is at risk of becoming a wound as discussed herein. For example, tissue at risk may include tissue on a bony prominence (at risk of deep tissue injury / damage) or pre-operative tissue (e.g., knee tissue) that may be cut (e.g., for joint replacement / surgical alteration / reconstruction).

[0054] Some embodiments relate to methods of treating wounds using the techniques disclosed herein in combination with one or more of the following: advanced footwear, rotation of the patient, cleaning (e.g., cleaning of diabetic foot ulcers), treatment of infection, systemic integration, antimicrobial, antibiotics, surgery, removal of tissue, affecting blood flow, physiotherapy, exercise, bathing, nutrition, hydration, nerve stimulation, ultrasound, electrical stimulation, oxygen therapy, microwave therapy, active ozone, antibiotics, antimicrobial, etc.

[0055] Alternatively or additionally, the wound may be treated using topical negative pressure and / or traditional advanced wound care that is not assisted by the use of applied negative pressure (also referred to as non-negative pressure therapy).

[0056] Advanced wound care may include the use of absorbent dressings, occlusive dressings, the use of antimicrobial and / or debridement agents in wound dressings or adjuncts, padding (e.g., cushioning or compression therapy such as stockings or bandages), etc.

[0057] In some embodiments, these wounds may be treated using traditional wound care, wherein a dressing may be applied to the wound to facilitate and promote wound healing.

[0058] Some embodiments relate to a method of making a wound dressing, comprising providing a wound dressing as disclosed herein.

[0059] Wound dressings that can be used in conjunction with the disclosed technology include any known in the art. The technology is applicable to negative pressure therapy treatments as well as non-negative pressure therapy treatments.

[0060] In some embodiments, the wound dressing includes one or more absorbent layers. The absorbent layer may be a foam or a superabsorbent.

[0061] In some embodiments, the wound dressing may include a dressing layer comprising a polysaccharide or modified polysaccharide, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl ether, polyurethane, polyacrylate, polyacrylamide, collagen, or a glue or a mixture thereof. Dressing layers comprising the listed polymers are known in the art to be useful for forming wound dressing layers for negative pressure therapy or non-negative pressure therapy.

[0062] In some embodiments, the polymer matrix can be a polysaccharide or a modified polysaccharide.

[0063] In some embodiments, the polymer matrix can be cellulose. The cellulosic material can include hydrophilic modified cellulose, such as methylcellulose, carboxymethylcellulose (CMC), carboxymethylcellulose (CEC), ethylcellulose, propylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, carboxyethyl cellulose sulfate, alkyl cellulose sulfonate, or a mixture thereof.

[0064] In certain embodiments, the cellulosic material may be a cellulose alkyl sulfonate. The alkyl portion of the alkyl sulfonate substituent may have an alkyl group of 1 to 6 carbon atoms, such as a methyl, ethyl, propyl, or butyl group. The alkyl portion may be branched or unbranched, and therefore, a suitable propyl sulfonate substituent may be a 1- or 2-methyl-ethyl sulfonate. The butyl sulfonate substituent may be a 2-ethyl-ethyl sulfonate, a 2,2-dimethyl-ethyl sulfonate or a 1,2-dimethyl-ethyl sulfonate. The alkyl sulfonate substituent may be an ethyl sulfonate. Cellulose alkyl sulfonates are described in WO10061225, US2016 / 114074, US2006 / 0142560, or US5,703,225, the disclosures of which are incorporated herein by reference in their entirety.

[0065] Cellulose alkyl sulfonates can have different degrees of substitution, chain length of the cellulose backbone structure and structure of the alkyl sulfonate substituent. Solubility and absorbability depend mainly on the degree of substitution: as the degree of substitution increases, cellulose alkyl sulfonates become increasingly soluble. It follows that as solubility increases, the absorbability increases.

[0066] In some embodiments, the wound dressing further comprises a top or cover layer.

[0067] The thickness of the wound dressing disclosed herein may be between 1 mm and 20 mm, or between 2 mm and 10 mm, or between 3 mm and 7 mm.

[0068] In some embodiments, the disclosed technology can 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 include:

[0069] an absorbent layer for absorbing exudate; and

[0070] A shielding element is provided for at least partially shielding the view of the absorption of wound exudate by the absorbent layer in use.

[0071] The shielding element may be partially translucent.

[0072] The shielding element may be a masking layer.

[0073] The non-negative pressure wound dressing may also include an area in or near the shielding element to allow viewing of the absorbent layer. For example, the shielding element layer may be disposed over a central area of ​​the absorbent layer and not over a border area of ​​the absorbent layer. In some embodiments, the shielding element is a hydrophilic material or is coated with a hydrophilic material.

[0074] The shielding element may comprise a three-dimensional knitted spacer fabric.Spacer fabrics are known in the art and may comprise a layer of knitted spacer fabric.

[0075] The shielding element may also include an indicator to indicate that a dressing change is required.

[0076] In some embodiments, the shielding element is provided as a layer at least partially above the absorbent layer and, in use, further away from the wound site than the absorbent layer.

[0077] The non-negative pressure wound dressing may also include a plurality of openings in the shielding element to allow fluid to move therethrough. The shielding element may include or be coated with a material having size exclusion properties for selectively allowing or preventing the passage of molecules of a predetermined size or weight.

[0078] The shielding element may be configured to at least partially shield optical radiation having a wavelength of 600 nm and less.

[0079] The shielding element may be configured to reduce light absorption by 50% or more.

[0080] The shielding element may be configured to produce a CIE L* value of 50 or greater, and optionally 70 or greater. In some embodiments, the shielding element may be configured to produce a CIE L* value of 70 or greater.

[0081] In some embodiments, the non-negative pressure wound dressing may further include at least one of a wound contact layer, a foam layer, an odor control element, a pressure resistant layer, and a cover layer.

[0082] In some embodiments, there is a cover layer, and the cover layer is a translucent film. Typically, the translucent film has a moisture vapor permeability of 500 g / m2 / 24 hours or more.

[0083] The translucent membrane can be a bacterial barrier.

[0084] In some embodiments, a non-negative pressure wound dressing as disclosed herein comprises a wound contact layer, and an absorbent layer overlies the wound contact layer. The wound contact layer carries an adhesive portion for forming a substantially fluid-tight seal over a wound site.

[0085] A non-negative pressure wound dressing as disclosed herein may include a shielding element and an absorbent layer provided as a single layer.

[0086] In some embodiments, the non-negative pressure wound dressings disclosed herein include a foam layer, and the material of the shielding element includes components that may be displaced or damaged by movement of the shielding element.

[0087] In some embodiments, the non-negative pressure wound dressing includes an odor control element, and in another embodiment, the dressing does not include an odor control element. When the odor control element is present, it can be dispersed within or adjacent to the absorbent layer or the shielding element. Alternatively, when the odor control element is present, it can be provided as a layer sandwiched between the foam layer and the absorbent layer.

[0088] In some embodiments, the disclosed technology for non-negative pressure wound dressings includes a method of manufacturing a wound dressing, comprising: providing an absorbent layer for absorbing wound exudate; and providing a shielding element, which is used to at least partially shield the observation of wound exudate absorbed by the absorbent layer during use.

[0089] In some embodiments, a non-negative pressure wound dressing may be adapted to provide protection at a wound site, comprising: an absorbent layer for absorbing wound exudate; and a shielding layer disposed above the absorbent layer and further from a wound-facing side of the wound dressing than the absorbent layer. The shielding layer may be disposed directly above the absorbent layer. In some embodiments, the shielding layer comprises a three-dimensional spacer fabric layer.

[0090] The shielding layer increases the area of ​​transmission of pressure applied to the dressing by 25% or more or the initial application area. For example, the shielding layer increases the area of ​​transmission of pressure applied to the dressing by 50% or more, optionally 100% or more, or optionally 200% or more.

[0091] The shielding layer may include 2 or more sub-layers, wherein a first sub-layer includes vias and another sub-layer includes vias, and the vias of the first sub-layer are offset from the vias of the other sub-layer.

[0092] A non-negative pressure wound dressing as disclosed herein may further comprise a permeable cover layer for allowing transmission of gas and vapor therethrough, the cover layer being disposed over the shielding layer, wherein the through-holes of the cover layer are offset from the through-holes of the shielding layer.

[0093] Non-negative pressure wound dressings may be appropriate for the treatment of pressure ulcers.

[0094] A more detailed description of the non-negative pressure dressing disclosed above is provided in WO2013007973, the entire contents of which are hereby incorporated by reference.

[0095] In some embodiments, the non-negative pressure wound dressing may be a multi-layer 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.

[0096] In some embodiments, the multi-layer wound dressings disclosed herein further comprise a liquid-impermeable film layer, wherein the support layer is located between the absorbent layer and the film layer.

[0097] The support layer disclosed herein may include a mesh. The mesh may include a geometric structure having a plurality of substantially geometric pores extending therethrough. For example, the geometric structure may include a plurality of bosses substantially evenly spaced apart and joined by polymer strands to form substantially geometric pores between the polymer strands.

[0098] The mesh may be formed from high density polyethylene.

[0099] The pores may have an area of ​​0.005 mm2 to 0.32 mm2.

[0100] The support layer may have a tensile strength of 0.05 Nm to 0.06 Nm.

[0101] The support layer may have a thickness of 50 μm to 150 μm.

[0102] In some embodiments, the support layer is located in close proximity to the absorbent layer. Typically, the support layer is bonded to the fibers in the top surface of the absorbent layer. The support layer may also include a bonding layer, wherein the support layer is heat laminated to the fibers in the absorbent layer through the bonding layer. The bonding layer may include a low melting point adhesive, such as an ethylene vinyl acetate adhesive.

[0103] In some embodiments, the multi-layer wound dressings disclosed herein further include an adhesive layer attaching the film layer to the support layer.

[0104] In some embodiments, the multi-layer wound dressing disclosed herein further comprises a wound contact layer positioned adjacent to the absorbent layer for positioning adjacent to the wound. The multi-layer wound dressing may further comprise a fluid transfer layer between the wound contact layer and the absorbent layer for transporting exudate away from the wound into the absorbent layer.

[0105] A more detailed description of the multi-layer wound dressing disclosed above is provided in UK patent application number GB1618298.2 filed on October 28, 2016, the entire contents of which are hereby incorporated by reference.

[0106] In some embodiments, the disclosed technology can be incorporated into a wound dressing comprising vertically overlapping materials, the wound dressing comprising: a first layer of absorbent material and a second layer of material, wherein the first layer is composed of at least one layer of non-woven textile fibers, the non-woven textile fibers being folded into multiple folds to form a pleated structure. In some embodiments, the wound dressing further comprises a second layer of material temporarily or permanently connected to the first layer of material.

[0107] Typically, the vertical overlapping material has been cut.

[0108] In some embodiments, the first layer has a pleated structure with a depth determined by the pleat depth or by the cut width.The first layer material may be a moldable lightweight fiber-based material, a blend of materials, or a composite layer.

[0109] The first layer material may include fibers made from synthetic natural or inorganic polymers, one or more of cellulose, protein or natural fibers of mineral origin.

[0110] The wound dressing may comprise two or more absorbent layers of material stacked on top of other materials in vertically overlapping layers, wherein the two or more layers have the same or different density or composition.

[0111] In some embodiments, the wound dressing may comprise only one layer of absorbent material of vertically overlapping material.

[0112] The absorbent material layer is a blend of natural or synthetic, organic or inorganic fibers and binder fibers or bicomponent fibers, the bicomponent fibers are typically PET with a low melting temperature PET coating to soften at a specified temperature and act as a binder throughout the blend.

[0113] In some embodiments, the absorbent material layer may be a blend of 5% to 95% thermoplastic polymer, and 5% to 95% by weight cellulose or its derivatives.

[0114] In some embodiments, the wound dressings disclosed herein have a second layer comprising a foam or a dressing securement.

[0115] The foam may be a polyurethane foam. The polyurethane foam may have an open-cell or closed-cell structure.

[0116] Dressing attachments may include bandages, tapes, mesh, or backing layers.

[0117] In some embodiments, the wound dressing disclosed herein comprises an absorbent material layer directly connected to a second layer by lamination or by an adhesive, and the second layer is connected to a dressing fixation layer. The adhesive may be an acrylic adhesive or a silicone adhesive.

[0118] In some embodiments, the wound dressing disclosed herein further comprises a superabsorbent fiber layer, or a viscose fiber layer or a polyester fiber layer.

[0119] In some embodiments, the wound dressing disclosed herein further comprises a backing layer. The backing layer can be a transparent or opaque film. Typically, the backing layer comprises a polyurethane film (typically a transparent polyurethane film).

[0120] A more detailed description of the multilayer wound dressing disclosed above is provided in UK patent application number GB1621057.7 filed on December 12, 2016 and UK patent application number GB1709987.0 filed on June 22, 2017, the entire contents of which are hereby incorporated by reference.

[0121] In some embodiments, a non-negative pressure wound dressing may include an absorbent component for a wound dressing, the component comprising a wound contact layer, the wound contact layer comprising gel-forming fibers bonded to a foam layer, wherein the foam layer is directly bonded to the wound contact layer by an adhesive, a polymer-based melt layer, by flame lamination, or by ultrasound.

[0122] The absorbent member may be in sheet form.

[0123] The wound contact layer may comprise a woven or non-woven or knitted layer of gel-forming fibres.

[0124] The foam layer can be an open-cell foam or a closed-cell foam, and is usually an open-cell foam. The foam layer is a hydrophilic foam.

[0125] The wound dressing may comprise a component forming an island in direct contact with the wound, the wound being surrounded by a perimeter of adhesive which attaches the dressing to the wound.The adhesive may be a silicone or acrylic adhesive, typically a silicone adhesive.

[0126] The wound dressing may be covered by a film layer on the surface of the dressing furthest from the wound.

[0127] A more detailed description of wound dressings of the type mentioned above is provided in EP2498829, the entire contents of which are hereby incorporated by reference.

[0128] In some embodiments, a non-negative pressure wound dressing may include a multi-layer wound dressing for wounds that produce high levels of exudate, characterized in that the dressing includes: a transmission layer having an MVTR of at least 300 gm2 / 24 hours; an absorbent core comprising gel-forming fibers capable of absorbing and retaining exudate; a wound contact layer comprising gel-forming fibers, which transfer exudate to the absorbent core; and a bonding layer positioned on the absorbent core, the absorbent core and the wound contact layer limiting lateral diffusion of exudate in the dressing to the wound area.

[0129] The wound dressing is capable of handling at least 6 g (or 8 g and 15 g) of fluid per 10 cm2 of the dressing over a 24 hour period.

[0130] The wound dressing may comprise gel-forming fibres which are chemically modified cellulose fibres in the form of a fabric. The fibres may comprise carboxymethylated cellulose fibres, typically sodium carboxymethylcellulose fibres.

[0131] The wound dressing may comprise a wound contact layer having a lateral wicking rate of 5 mm / min to 40 mm / min.The wound contact layer may have a fibre density of between 25 gm2 and 55 gm2, for example 35 gm2.

[0132] The absorbent core may have an exudate absorbency of at least 10 g / g and typically a lateral wicking rate of less than 20 mm per minute.

[0133] The absorbent core may have a blend in the range of up to 25 wt% cellulosic fibers and 75 to 100 wt% gel-forming fibers.

[0134] Alternatively, the absorbent core may have a blend in the range of up to 50 wt% cellulose fibers and 50 to 100 wt% gel-forming fibers. For example, the blend is in the range of 50 wt% cellulose fibers and 50 wt% gel-forming fibers.

[0135] The fiber density in the absorbent core may be between 150 gm2 and 250 gm2, or about 200 gm2.

[0136] The wound dressing may shrink less than 25% or less than 15% of its original size / dimensions when wet.

[0137] 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.

[0138] The wound dressing may comprise one or more layers selected from the group comprising a soluble drug film layer, an odour absorbing layer, a diffusion layer and an additional adhesive layer.

[0139] Wound dressings are available in 2mm and 4mm thickness.

[0140] The wound dressing may be characterized in that a bonding layer bonds the absorbent core to adjacent layers. In some embodiments, the bonding layer may be positioned on the wound-facing side of the absorbent core or on the non-wound-facing side of the absorbent core. In some embodiments, the bonding layer is positioned between the absorbent core and the wound contact layer. The bonding layer is a polyamide web.

[0141] A more detailed description of wound dressings of the type mentioned above is provided in EP1718257, the entire contents of which are hereby incorporated by reference.

[0142] In some embodiments, the non-negative pressure wound dressing may be a compression bandage.Compression bandages are known to be used to treat, for example, edema of the lower extremities and other venous and lymphatic diseases.

[0143] Compression bandage systems usually use multiple layers, including a padding layer between the skin and the compression layer or layers. Compression bandages can be used to treat wounds such as venous leg ulcers.

[0144] In some embodiments, the compression bandage may include a bandage system including an inner skin-facing layer and an elastic outer layer, the inner layer including a first foam layer and a second layer of an absorbent nonwoven web, the inner and outer layers being sufficiently elongated to be wrapped around a patient's limb. This type of compression bandage is disclosed in WO99 / 58090, the entire contents of which are hereby incorporated by reference.

[0145] In some embodiments, the compression bandage system comprises: a) an inner elongated elastic bandage facing the skin, comprising: (i) an elongated elastic base, and

[0146] (ii) an elongated foam layer adhered to one side of the substrate and extending 33% or more across the side of the substrate in a transverse direction and 67% or more across the side of the substrate in a longitudinal direction; and b) an outer elongated self-adhesive elastic bandage having a compressive force when extended; wherein, in use, the foam layer of the inner bandage faces the skin and the outer bandage covers the inner bandage. Compression bandages of this type are disclosed in WO2006 / 110527, the entire contents of which are hereby incorporated by reference.

[0147] In some embodiments, other compression bandage systems, such as those disclosed in US 6,759,566 and US 2002 / 0099318, the entire contents of which are hereby incorporated by reference.

[0148] Negative pressure wound dressing

[0149] In some embodiments, treatment of such wounds may be performed using negative pressure wound therapy, wherein reduced pressure or negative pressure may be applied to the wound to facilitate and promote healing of the wound. It will also be appreciated that the wound dressings and methods as described herein may be applied to other parts of the body and are not necessarily limited to wound treatment.

[0150] It should be understood that embodiments of the present disclosure are generally suitable for use in topical negative pressure ("TNP") therapy systems. In simple terms, negative pressure wound therapy helps to close and heal a variety of "difficult to heal" wounds by reducing tissue edema, promoting blood flow and granulation tissue formation, removing excess exudate, and can reduce bacterial load (thereby reducing the risk of infection). In addition, the therapy allows the wound to be less disturbed, thereby healing faster. TNP therapy systems can also assist in the healing of surgically closed wounds by removing fluids and by helping to stabilize tissue in the immediate vicinity of the closure site. Additional beneficial uses of TNP therapy can be found in grafts and flaps, where removal of excess fluids is important and close proximity of the graft to the tissue is required to ensure tissue viability.

[0151] Negative pressure therapy can be used to treat open or chronic wounds that are too large to close spontaneously or otherwise fail to heal by applying negative pressure to the wound site. Topical negative pressure (TNP) therapy or negative pressure wound therapy (NPWT) involves placing a fluid-impermeable or semi-permeable covering over the wound, using various means to seal the covering to the patient's tissue surrounding the wound, and connecting a negative pressure source (such as a vacuum pump) to the covering in a manner that generates and maintains negative pressure beneath the covering. It is believed that this negative pressure promotes wound healing by promoting the formation of granulation tissue at the wound site and aiding the body's normal inflammatory process while removing excess fluid that may contain adverse cytokines or bacteria.

[0152] Some of the dressings used in NPWT can include many different types of materials and layers, such as gauze, pads, foam pads, or multi-layer wound dressings. An example of a multi-layer wound dressing is the PICO dressing available from Smith & Nephew, which includes a wound contact layer and a superabsorbent layer beneath a backing layer to provide a canisterless system for treating wounds with NPWT. The wound dressing can be sealed to a suction port that provides a connection to a length of tubing that can be used to pump fluid out of the dressing or to transfer negative pressure from a pump to the wound dressing. Additionally, the 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 wet wound environment dressing for treating wounds without the use of negative pressure.

[0153] As used herein, a reduced pressure level or negative pressure level (e.g., -X mmHg) represents a pressure level relative to normal ambient atmospheric pressure, which may correspond to 760 mmHg (or 1 atm, 29.93 inHg, 101.325 kPa, 14.696 psi, etc.). Therefore, a negative pressure value of -X mmHg reflects an absolute pressure that is X mmHg lower than 760 mmHg, or in other words, reflects an absolute pressure of (760-X) mmHg. In addition, a negative pressure that is "lower" or "smaller" than X mmHg corresponds to a pressure that is closer to atmospheric pressure (e.g., -40 mmHg is smaller than -60 mmHg). A negative pressure that is "higher" or "larger" than -X mmHg corresponds to a pressure that is further away from atmospheric pressure (e.g., -80 mmHg is larger than -60 mmHg). In some embodiments, the local ambient atmospheric pressure is used as a reference point, and such a local atmospheric pressure may not necessarily be, for example, 760 mmHg.

[0154] The negative pressure range of some embodiments of the present disclosure may be about -80mmHg, or between about -20mmHg and -200mmHg. It should be noted that these pressures are based on normal ambient atmospheric pressure (which may be 760mmHg). Therefore, in reality -200mmHg would be about 560mmHg. In some embodiments, the pressure range may be between about -40mmHg and -150mmHg. Alternatively, a pressure range of up to -75mmHg, up to -80mmHg, or exceeding -80mmHg may be used. In other embodiments, a pressure range of less than -75mmHg may be used. Alternatively, the negative pressure device may supply a pressure range exceeding about -100mmHg, or even -150mmHg.

[0155] In some embodiments of the wound closure devices described herein, increased wound contraction can cause increased tissue expansion in the surrounding wound tissue. This effect can be enhanced by changing the force applied to the tissue (e.g., by changing the negative pressure applied to the wound over time), which may be combined with increased tension applied to the wound via multiple embodiments of the wound closure device. In some embodiments, for example, the negative pressure can be changed over time using a sine wave, a square wave, or synchronized with one or more patient physiological indicators (e.g., a heartbeat). Examples of such applications in which additional disclosures related to the foregoing can be found include U.S. Patent No. 8,235,955, entitled "Wound treatment apparatus and method", published on August 7, 2012; and U.S. Patent No. 7,753,894, entitled "Wound cleansing apparatus with stress", published on July 13, 2010. The disclosures of both patents are hereby incorporated by reference in their entirety.

[0156] Embodiments of the wound dressings, wound dressing components, wound treatment devices and methods described herein may also be used in combination or in addition to those described in the following documents, including: International Application No. PCT / IB2013 / 001469, entitled “APPARATUSES AND METHODS FOR NEGATIVE PRESSURE WOUND THERAPY,” filed on May 22, 2013 and published as WO 2013 / 175306 A2 on November 28, 2013; U.S. Patent Application No. 14 / 418,908, entitled “WOUND DRESSING AND METHOD OF TREATMENT,” filed on January 30, 2015 and published as US 2015 / 0190286A1 on July 9, 2015, the disclosures of which are hereby incorporated herein by reference in their entirety. Embodiments of the wound dressings, wound dressing components, wound treatment devices, and methods described herein may also be used in combination or in addition to those described in the following documents, including: U.S. patent application Ser. No. 13 / 092,042, filed on April 21, 2011, and published as US2011 / 0282309, entitled “WOUND DRESSING AND METHOD OF USE”; and U.S. patent application Ser. No. 14 / 715,527, filed on May 18, 2015, and published as US2016 / 0339158 A1 on November 24, 2016, entitled “FLUIDIC CONNECTOR FOR NEGATIVE PRESSURE WOUND THERAPY”, the disclosure of each of the above patents being incorporated herein by reference, including additional details about embodiments of wound dressings, wound dressing components and principles, and materials for wound dressings.

[0157] In addition, some embodiments of TNP wound treatment involving wound dressings in combination with the pumps and / or associated electronics described herein may also be used in combination or in addition to those described in international application PCT / EP2016 / 059329, entitled “REDUCED PRESSURE APPARATUS AND METHODS,” filed on April 26, 2016 and published on November 3, 2016 as WO 2016 / 174048.

[0158] In some embodiments of the wound closure device described herein, increased wound contraction can cause increased tissue expansion in the surrounding wound tissue. This effect can be enhanced by changing the force applied to the tissue (e.g., by changing the negative pressure applied to the wound over time), which may be combined with the increased tension applied to the wound via multiple embodiments of the wound closure device. In addition, there may be additional effects on tissues in close proximity to the filler, for example, because the reaction force of the elastic filler presses on the tissue, the tissue is compressed. This compression can cause local hypoxia due to vascular occlusion. In wider peripheral tissues, this expansion can cause vascular dilation. Malmsjo and Borgquist provided more details in "NPWT settings and dressing choices made easy" published in Wounds International in May 2010, which is incorporated herein by reference in its entirety. For example, in wounds without ischemic risk, the increase and decrease of blood flow caused by the pressure from the wound dressing may be beneficial to wound healing. The increase in blood flow can improve the supply of oxygen and nutrients to the tissue, and improve the penetration of antibiotics and the removal of waste products. In addition, reduced blood flow can stimulate angiogenesis, thereby promoting the formation of granulation tissue.

[0159] Wound healing

[0160] Those skilled in the art will appreciate that the embodiments described herein, particularly with reference to Euler video magnification (EVM), are not only applicable to situations involving NPWT. Rather, such embodiments may be broadly applicable to situations where NPWT is not necessarily required, such as assessing intact tissue or providing additional treatment to a wound.

[0161] Wounds can be generally classified as open or closed wounds, usually depending on the manner in which the wound is caused. As described above, these techniques can be applied to open or closed wounds, depending on the specific circumstances of the embodiment. Open wounds may be caused by a variety of events, including: incisions, lacerations, abrasions, punctures, penetrations, amputations, and other means. Closed wounds may be caused by vascular damage, resulting in hematoma formation, and / or internal injuries caused by crushing. In addition, wounds may involve various tissue layers, for example, shallower wounds may only involve the top layer of the skin, while deeper wounds may involve lower subcutaneous tissue layers, such as subcutaneous tissue, including lower connective tissue and fat layers. In some embodiments, the wound may even include internal organs deep below the skin. Some wounds, such as wounds caused by pressure injuries, may begin to occur in deeper tissue layers and not become apparent on the skin surface until much later.

[0162] In addition to the above-mentioned NPWT treatments, wounds can be treated by a wide variety of techniques and materials. For example, wounds can be treated by debridement to remove dead and / or necrotic tissue. Wounds can be treated with various types of dressings, including dry and moist dressings, chemically impregnated dressings, foam dressings, hydrogel dressings, hydrocolloid dressings, film dressings, and other suitable dressings. Wounds can be further treated with bioactive molecules, such as antimicrobial agents, growth factors, anti-inflammatory agents, analgesics, and other suitable treatments. Such treatments can be incorporated into the aforementioned dressings.

[0163] More details about wounds and wound management, particularly wounds caused by pressure injuries, can be found in the article "Pressure Injuries (Pressure Ulcers) and Wound Care" by Kirman et al., published in Medscape in March 2017, which is incorporated herein by reference in its entirety. For example, the most common candidates for pressure ulcers include: the elderly, people with chronic illness (e.g., cancer, stroke, or diabetes), people who are immobile (e.g., because of fractures, arthritis, or pain), people who are weak or debilitated, people with altered mental status (e.g., under the influence of narcotics, anesthesia, or coma), and / or people with reduced or paralyzed sensation. Possible secondary factors include: illness or debilitation that increases the formation of pressure ulcers, fever (increased metabolic demand), precursor ischemia, sweating that promotes skin maceration, incontinence that causes skin irritation and contamination, edema, jaundice, itching, and dryness (dry skin). Additionally, prevention of pressure ulcer injuries may include: organized body rotation, appropriate bed positioning, protection of bony prominences, skin care, control of spasticity and prevention of contractures, use of support surfaces / specialized beds, nutritional support, and maintaining current activity level, mobility, and range of motion.

[0164] Negative pressure system

[0165] Figure 1 One embodiment of a negative pressure or reduced pressure wound therapy (or TNP) system 100 is shown, which includes a wound filler 130 placed in a wound cavity 110, which is sealed by a wound cover 120. The wound filler 130 and the wound cover 120 in combination can be referred to as a wound dressing. A single-lumen or multi-lumen tube or conduit 140 is connected to the wound cover 120, wherein a pump assembly 150 is configured to supply reduced pressure. The wound cover 120 can be in fluid communication with the wound cavity 110. In any system embodiments disclosed herein, as Figure 1In the embodiment shown in , the pump assembly can be a canisterless pump assembly (meaning that the exudate is collected in the wound dressing or transferred via tube 140 to be collected at another location). However, any of the pump assembly embodiments disclosed herein can be configured to include or support a canister. Additionally, in any of the system embodiments disclosed herein, any of the pump assembly embodiments can be mounted to or supported by a dressing, or adjacent to a dressing.

[0166] The wound packing 130 may be of any suitable type, such as a hydrophilic or hydrophobic foam, gauze, an inflatable bag, etc. The wound packing 130 may be conformable to the wound cavity 110 such that it substantially fills the cavity. The wound cover 120 may provide a substantially fluid-impermeable seal over the wound cavity 110. The wound cover 120 may have a top side and a bottom side, with the bottom side adhesively (or in any other suitable manner) sealed to the wound cavity 110. The conduit 140 or lumen, or any other conduit or lumen disclosed herein, may be formed of polyurethane, PVC, nylon, polyethylene, silicone, or any other suitable material.

[0167] Some embodiments of the wound cover 120 may have a port (not shown) configured to receive an end of the conduit 140. For example, the port may be a Renays Soft Port available from Smith & Nephew. In other embodiments, the conduit 140 may additionally pass through or under the wound cover 120 to supply reduced pressure to the wound cavity 110 so as to maintain a target or desired reduced pressure level in the wound cavity. The conduit 140 may be any suitable article configured to provide an at least substantially sealed fluid flow path between the pump assembly 150 and the wound cover 120 so as to supply the reduced pressure provided by the pump assembly 150 to the wound cavity 110.

[0168] The wound cover 120 and wound filler 130 may be provided as a single article or as an integral single unit. In some embodiments, no wound filler is provided and the wound cover itself may be considered a wound dressing. The wound dressing may then be connected to a negative pressure source, such as a pump assembly 150, via a conduit 140. The pump assembly 150 may be miniaturized or portable, although larger conventional pumps may also be used.

[0169] The wound cover 120 may be positioned over a wound site to be treated. The wound cover 120 may form a substantially sealed cavity or housing over the wound site. In some embodiments, the wound cover 120 may be configured with a membrane having a high water vapor permeability to allow excess fluid to evaporate, and may have a superabsorbent material contained therein to safely absorb wound exudate. It should be appreciated that reference is made to wounds throughout the specification. In this sense, it should be understood that the term wound should be broadly interpreted as, and encompasses, open wounds and closed wounds, where the skin is torn, cut or punctured, or where trauma has caused a contusion, or any other surface or other condition or defect on the patient's skin, or those wounds that would benefit from reduced pressure treatment. Thus, a wound is broadly defined as any damaged tissue area that may or may not produce fluid. Examples of such wounds include, but are not limited to, acute wounds, chronic wounds, surgical and other incisions, subacute and dehiscent wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure sores, ostomies, surgical wounds, traumatic and venous ulcers, etc. The components of the TNP system described herein may be particularly suitable for incisional wounds that shed small amounts of wound exudate.

[0170] Some embodiments of the system are designed to operate without the use of an exudate tank. Some embodiments can be configured to support an exudate tank. In some embodiments, the pump assembly 150 and tubing 140 are configured so that the tubing 140 can be quickly and easily removed from the pump assembly 150, which can facilitate or improve the process of dressing or pump replacement (if necessary). Any of the pump embodiments disclosed herein can be configured to have any suitable connection between the tubing and the pump.

[0171] In some embodiments, the pump assembly 150 can be configured to deliver a negative pressure of about -80 mmHg, or about -20 mmHg to 200 mmHg. It should be noted that these pressures are relative to normal ambient atmospheric pressure, so -200 mmHg will actually be about 560 mmHg. The pressure range can be between about -40 mmHg and -150 mmHg. Alternatively, a pressure range of up to -75 mmHg, up to -80 mmHg, or exceeding -80 mmHg can be used. In addition, a pressure range of less than -75 mmHg can be suitable. Alternatively, the pump assembly 150 can supply a pressure range exceeding about -100 mmHg or even 150 mmHg.

[0172] In operation, the wound filler 130 is inserted into the wound cavity 110, and the wound cover 120 is placed to seal the wound cavity 110. The pump assembly 150 provides a source of negative pressure to the wound cover 120, which is transmitted to the wound cavity 110 via the wound filler 130. Fluid (e.g., wound exudate) is sucked through the conduit 140 and can be stored in a tank. In some embodiments, the fluid is absorbed by the wound filler 130 or one or more absorbent layers (not shown).

[0173] Wound dressings that can be used with the pump assembly and other embodiments of the present application include Renasys-F, Renasys-G, Renasys AB, and Pico Dressings available from Smith & Nephew. Other descriptions of such wound dressings and other components of the negative pressure wound therapy system that can be used with the pump assembly and other embodiments of the present application can be found in U.S. Patent Publication Nos. 2011 / 0213287, 2011 / 0282309, 2012 / 0116334, 2012 / 0136325, and 2013 / 0110058, which are incorporated herein by reference in their entirety. In other embodiments, other suitable wound dressings can be used.

[0174] Pump Assemblies and Tanks

[0175] Figure 2A A front view of a pump assembly 230 and a canister 220 is shown according to some embodiments. As shown, the pump assembly 230 and the canister are connected to form a negative pressure wound therapy device. In some embodiments, the pump assembly 230 can be similar or identical to the pump assembly 150.

[0176] The pump assembly 230 includes one or more indicators, such as a visual indicator 202 configured to indicate an alarm, and a visual indicator 204 configured to indicate the status of the TNP system. The indicators 202 and 204 can be configured to alert a user (e.g., a patient or a medical care provider) of various operating or fault conditions of the system, including alerting the user of a normal or correct operating state, a pump failure, power supply to the pump or power failure, detection of a leak in the wound cover or flow path, a suction blockage, or any other similar or suitable state or combination thereof. The pump assembly 230 can include additional indicators. The pump assembly can use a single indicator or multiple indicators. Any suitable indicator can be used, such as visual, audio, tactile indicators, etc. The indicator 202 can be configured to signal an alarm state, such as a full tank, low power, disconnection of the catheter 140, a seal rupture in the wound seal 120, etc. The indicator 202 can be configured to display a flashing red light to attract the user's attention. The indicator 204 may be configured to signal the status of the TNP system, such as treatment delivery is normal, a leak is detected, etc. The indicator 204 may be configured to display one or more different colors of light, such as green, yellow, etc. For example, green light may be emitted when the TNP system is operating properly, and yellow light may be emitted to indicate a warning.

[0177] The pump assembly 230 includes a display or screen 206 mounted in a recess 208 formed in the housing of the pump assembly. The display 206 may be a touch screen display. The display 206 may support playback of audio-visual (AV) content, such as an instructional video. As described below, the display 206 may be configured to present multiple screens or graphical user interfaces (GUIs) for configuring, controlling, and monitoring the operation of the TNP system. The pump assembly 230 includes a gripping portion 210 formed in the housing of the pump assembly. The gripping portion 210 may be configured to assist a user in holding the pump assembly 230, for example, during removal of the tank 220. The tank 220 may be replaced by another tank, for example, when the tank 220 is filled with fluid.

[0178] The pump assembly 230 includes one or more keys or buttons configured to allow a user to operate and monitor the operation of the TNP system. As shown, buttons 212a, 212b, and 212c (collectively referred to as button 212) are included here. Button 212a can be configured as a power button to turn on / off the pump assembly 230. Button 212b can be configured as a play / pause button for delivering negative pressure therapy. For example, pressing button 212b can cause the therapy to start, and then pressing button 212b can cause the therapy to pause or end. Button 212c can be configured to lock the display 206 or button 212. For example, button 212c can be pressed so that the user does not inadvertently change the delivery of the therapy. Button 212c can be pressed to unlock the control. In other embodiments, additional buttons can be used, or one or more of the buttons 212a, 212b, or 212c shown can be omitted. Multiple key presses or key sequences can be used to operate the pump assembly 230.

[0179] The pump assembly 230 includes one or more locking notches 222 formed in the cover. In the illustrated embodiment, two locking notches 222 may be formed on the side of the pump assembly 230. The locking notches 222 may be configured to allow the canister 220 to be attached and detached using one or more canister locks 221. The pump assembly 230 includes an air outlet 224 for allowing air removed from the wound cavity 110 to escape. The air entering the pump assembly may pass through one or more suitable filters, such as an antibacterial filter. This may maintain the reusability of the pump assembly. The pump assembly 230 includes one or more belt mounts 226 for connecting a carrying belt to the pump assembly 230 or for attaching a stand. In the illustrated embodiment, two belt mounts 226 may be formed on the side of the pump assembly 230. In some embodiments, various of these features are omitted, or various additional features are added to the pump assembly 230.

[0180] The tank 220 is configured to hold fluid (e.g., exudate) removed from the wound cavity 110. The tank 220 includes one or more locks 221 for attaching the tank to the pump assembly 230. In the illustrated embodiment, the tank 220 includes two locks 221 on the side of the tank. The exterior of the tank 220 may be formed of frosted plastic so that the tank is substantially opaque and the tank and the contents are substantially hidden from the plan view. The tank 220 includes a gripping portion 214 formed in the shell of the tank. The gripping portion 214 may be configured to allow the user to hold the pump assembly 220, for example, during the removal of the tank from the device 230. The tank 220 includes a substantially transparent window 216, which may also include a volume scale. For example, the 300 mL tank 220 shown includes scales of 50 mL, 100 mL, 150 mL, 200 mL, 250 mL, and 300 mL. Other embodiments of the tank may hold different volumes of fluid and may include different scales. For example, the tank may be a 800 mL tank. The canister 220 includes a tubing passage 218 for connection to the catheter 140. In some embodiments, various of these features, such as the gripping portion 214, are omitted, or various additional features are added to the canister 220. Any of the disclosed canisters may include or omit a curing agent.

[0181] Figure 2B A rear view of a pump assembly 230 and a tank 220 according to some embodiments is shown. The pump assembly 230 includes a speaker port 232 for generating sound. The pump assembly 230 includes a filter access door 234 having a screw for removing the access door 234, accessing and replacing one or more filters (e.g., antibacterial or deodorizing filters). The pump assembly 230 includes a gripping portion 236 formed in the housing of the pump assembly. The gripping portion 236 may be configured to allow a user to hold the pump assembly 230, for example, during the removal of the tank 220. The pump assembly 230 includes one or more covers 238 configured as screw covers, or feet or protectors for placing the pump assembly 230 on a surface. The cover 230 may be formed of rubber, silicone, or any other suitable material. The pump assembly 230 includes a power socket 239 for charging and recharging the internal battery of the pump assembly. The power socket 239 may be a direct current (DC) socket. In some embodiments, the pump assembly may include a disposable power source, such as a battery, so that a power socket is not required.

[0182] The tank 220 includes one or more feet 244 for placing the tank on a surface. The feet 244 may be formed of rubber, silicone, or any other suitable material, and may be angled at a suitable angle so that the tank 220 remains stable when placed on a surface. The tank 220 includes a tube mounting protrusion 246 configured to allow one or more tubes to leave the front of the device. The tank 220 includes a table or bracket 248 for supporting the tank when it is placed on a surface. As described below, the bracket 248 may pivot between an open position and a closed position. In the closed position, the bracket 248 may be locked to the tank 220. In some embodiments, the bracket 248 may be made of an opaque material, such as plastic. In other embodiments, the bracket 248 may be made of a transparent material. The bracket 248 includes a gripping portion 242 formed in the bracket. The gripping portion 242 may be configured to allow a user to place the bracket 248 in a closed position. The bracket 248 includes a hole 249 to allow a user to place the bracket in an open position. The hole 249 may be sized to allow a user to extend the bracket using a finger.

[0183] Figure 2C A view of a pump assembly 230 separated from a canister 220 is shown according to some embodiments. The pump assembly 230 includes a vacuum attachment, connector, or inlet 252 through which a vacuum pump transmits negative pressure to the canister 220. The pump assembly aspirates fluid, such as gas, from the wound through the inlet 252. The pump assembly 230 includes a USB access door 256 configured to allow access to one or more USB ports. In some embodiments, the USB access door is omitted and the USB port is accessed via door 234. The pump assembly 230 may include additional access doors configured to allow access to additional serial, parallel, or hybrid data transfer interfaces, such as SD, compact disk (CD), DVD, FireWire, Thunderbolt, PCI Express, etc. In other embodiments, one or more of these additional ports are accessed via door 234.

[0184] Pump Assembly Electronics and Components

[0185] Figure 3A A schematic diagram 300A of electrical components of a pump assembly (such as pump assembly 230) according to some embodiments is illustrated. The electrical components may be operable to accept user input, provide output to a user, operate a pump system and a TNP system, provide network connectivity, and the like. The electrical components may be mounted on one or more printed circuit boards (PCBs). As shown, the pump assembly may include multiple processors.

[0186] The pump assembly may include a user interface processor or controller 310 configured to operate one or more components for accepting user input and providing output to the user, such as display 206, button 212, etc. The pump assembly input and output from the pump assembly may be controlled by an input / output (I / O) module 320. For example, the I / O module may receive data from one or more ports, such as serial, parallel, hybrid ports, etc. The processor 310 also receives data from one or more expansion modules 360 and provides data to one or more expansion modules, such as one or more USB ports, SD ports, compact disk (CD) drives, DVD drives, FireWire ports, Thunderbolt ports, PCI Express ports, etc. The processor 310, along with other controllers or processors, stores data in one or more memory modules 350, which may be internal and / or external to the processor 310. Any suitable type of memory may be used, including volatile or non-volatile memory, such as RAM, ROM, magnetic memory, solid-state memory, magnetoresistive random access memory (MRAM), etc.

[0187] In some embodiments, the processor 310 can be a general purpose processor, such as a low power processor. In other embodiments, the processor 310 can be a dedicated processor. The processor 310 can be configured as a "central" processor in the electronic architecture of the pump assembly, and the processor 310 can coordinate the activities of other processors, such as the step-down control processor 370, the communication processor 330, and one or more additional processors 380 (e.g., a processor for controlling the display 206, a processor for controlling the button 212, etc.). The processor 310 can run a suitable operating system, such as Linux, Windows CE, VxWorks, etc.

[0188] The reduced pressure control processor 370 can be configured to control the operation of a reduced pressure source, such as a pump 390 and a valve 392. The pump 390 can be a suitable pump, such as a diaphragm pump, a peristaltic pump, a rotary pump, a rotary vane pump, a scroll pump, a screw pump, a liquid ring pump, a diaphragm pump operated by a piezoelectric transducer, a voice coil pump, etc. The valve 392 can be a suitable valve, such as a solenoid valve, a diaphragm valve, etc., and is positioned, for example, downstream (or before) the exhaust port of the pump assembly or in the fluid flow path between the pump assembly and the wound dressing. The valve 392 can be a single valve or composed of a plurality of different valves.

[0189] The pressure relief control processor 370 can measure the pressure in the fluid flow path using data received from one or more pressure sensors, calculate the fluid flow rate, and control the pump 390 and the valve 392. The pressure relief control processor 370 can control the pump motor of the pump 390 so that the desired negative pressure level is achieved in the wound cavity 110. The desired negative pressure level can be a pressure set or selected by a user. In various embodiments, the pressure relief control processor 370 controls the pump (e.g., pump motor) using pulse width modulation (PWM). The control signal for driving the pump 390 can be a PWM signal with a duty cycle of 0-100%. In addition, the pressure relief control processor 370 can control the opening and closing of the valve 392 so that the desired negative pressure level is achieved in the wound cavity 110. The desired negative pressure level can be a pressure set or selected by a user, or automatically set according to an operating mode or setting of the pump assembly. In various embodiments, the pressure relief control processor 370 controls the opening and closing of the valve 392 using PWM. The control signal for controlling or driving the valve 392 can be a PWM signal with a duty cycle of 0-100%.

[0190] The reduced pressure control processor 370 can perform flow rate calculations and detect various conditions in the flow path. The reduced pressure control processor 370 can transmit information to the processor 310. The reduced pressure control processor 370 can include internal memory, or can utilize the memory 350. The reduced pressure control processor 370 can be a low power processor.

[0191] The communication processor 330 can be configured to provide a wired or wireless connection. The communication processor 330 can utilize one or more antennas 340 to send and receive data. The communication processor 330 can provide one or more of the following types of connections: global positioning system (GPS) technology, cellular connection (e.g., 2G, 3G, LTE, 4G), WiFi connection, Internet connection, etc. The connection can be used for various activities, such as pump component location tracking, asset tracking, compliance monitoring, remote selection, log upload, alarm and other operational data, and adjustment of treatment settings, software or firmware upgrades, etc. The communication processor 330 can provide dual GPS / cellular functionality. The cellular function can be, for example, a 3G function. The pump component can include a SIM card, and SIM-based location information can be obtained.

[0192] The communication processor 330 may communicate information to the processor 310. The communication processor 330 may include internal memory, or may utilize the memory 350. The communication processor 330 may be a low power processor.

[0193] In some embodiments, the device can upload any data stored, maintained and / or tracked by the pump assembly using the connection provided by the communication processor 330. The device can also download various operational data, such as treatment selections and parameters, firmware and software patches and upgrades, etc.

[0194] Figure 3B A block diagram of certain components 300B of a pump assembly (e.g., pump assembly 230) according to some embodiments is illustrated. Component 300B includes an inlet 395 (which may be similar to inlet 252), a pump 390, a valve 392, an exhaust port 396, a pressure sensor 397, and a reduced pressure control processor 370.

[0195] The pump 390 can provide negative pressure in a fluid flow path that connects the pump 390 (via the inlet 395) to a wound dressing placed over a wound, such that negative pressure is provided to the inlet 395 and then provided to the wound dressing (e.g., through a canister). The valve 392 can be opened (e.g., partially or completely) to allow air, gas, or other fluid to enter, thereby providing positive pressure in the fluid flow path. In some embodiments, the pump 390 under the control of the reduced pressure control processor 370 can additionally or alternatively provide positive pressure in the fluid flow path, such as by reversing the operation of the pump 390. Additionally or alternatively, another pump different from the pump 390 and controllable by the reduced pressure control processor 370 can be included to provide positive pressure in the fluid flow path.

[0196] In some embodiments, the reduced pressure control processor 370 can use data received from one or more pressure sensors (e.g., pressure sensor 397) to measure the pressure in the fluid flow path near or at the inlet 395 (or any other location in the fluid flow path, such as a wound), calculate the rate of fluid flow, and control the pump 390 and valve 392. For example, the reduced pressure control processor 370 can control one or more pump actuators (e.g., a pump motor of the pump 390) or one or more valve actuators (e.g., a solenoid of the valve 392) to achieve a desired negative (or positive) pressure level at the wound. The desired negative pressure level (or pressure set point) can be a pressure set or selected by a user, or automatically set according to the operating mode or settings of the pump assembly.

[0197] Component 300B may also include one or more additional sensors (not shown), such as a tachometer, positioned to detect or determine an activity level of pump 390 (e.g., a pump motor) and provide an indication to reduced pressure control processor 370 in response to the activity level of pump 390. For example, the tachometer may be separate from pump 390 (e.g., external to the pump) and positioned proximate to or coupled to pump 390, and the tachometer may detect rotations (e.g., partial rotations, full rotations, or multiple partial or full rotations) of the pump motor of pump 390.

[0198] In some embodiments, at least two pressure sensors may be positioned in or fluidly connected to the fluid flow path to allow differential measurement of pressure. For example, a first pressure sensor may be positioned upstream of the wound (such as at or near the inlet of the pump assembly), and a second pressure sensor may be positioned to detect pressure at or near the wound dressing, or at or near the tank. This configuration may be achieved by having a second fluid flow path in addition to one or more lumens forming a first fluid flow path connecting the pump assembly to the wound, the second fluid flow path comprising one or more lumens connecting the pump assembly to the wound dressing and for enabling the second pressure sensor to monitor the pressure at or near the wound dressing or at or near the tank. The first and second fluid flow paths may be fluidically isolated from each other. When at least two pressure sensors are used, the rate of change of the pressure (e.g., peak-to-peak pressure or maximum pressure) in the first and second fluid flow paths may be determined, and the pressure difference detected between the first and second pressure sensors may be determined. These values ​​may be used individually or together to detect various operating conditions, such as leaks, blockages, tank fullness, the presence of blood in the first fluid flow path or the second fluid flow path, and the like. Furthermore, in some embodiments, multiple redundant pressure sensors may be provided in case one or more of the pressure sensors fails.

[0199] Delivering Negative Pressure Wound Therapy

[0200] In some embodiments, the pump assembly controls the vacuum pump to deliver negative pressure therapy to the wound according to a selected or programmed protocol.Pump control may be performed by reduced pressure control processor 370 alone or in combination with processor 310 .

[0201] For example, the user can choose to operate continuously at a desired pressure (or negative pressure set point). The pump assembly can activate a vacuum pump to reduce or pull down (e.g., below the dressing) the pressure at the wound to reach the set point. As explained below, the pull-down can be performed by increasing the negative pressure at the wound, which is limited by the maximum change in negative pressure per unit time, which is called compression, until the set point (or another selected pressure value as explained below) has been reached. Wound drawdown can be defined as the period immediately after treatment has begun, during which the wound has not yet reached the set point. As explained below, at the end of this period, the set point is reached, and the flow rate in the fluid flow path should be below the leak (or high flow) threshold and above the low vacuum threshold, otherwise, the appropriate alarm will be activated.

[0202] As another example, the user can select to intermittently operate between two desired pressures (or high and low pressure set points). The pump assembly can activate the vacuum pump to reduce or pull down the pressure at the wound to reach the high set point. Subsequently, the pump assembly can increase the pressure at the wound to reach the low set point. As explained below, the reduction and increase of negative pressure can be performed according to the compression setting.

[0203] As yet another example, compression can be used anytime there is a change in the pressure set point (which can include ceasing to deliver negative pressure). In some embodiments, different compression settings can be used for set point changes, resulting in a decrease or increase in pressure at the wound. In various embodiments, the compression setting can be adjusted when the pressure set point is reached.

[0204] Figure 4 A process 500 for providing negative pressure wound therapy according to some embodiments is illustrated. The process 500 may be performed by the reduced pressure control processor 370, alone or in combination with the processor 310, and utilize one or more other components described herein or other systems not shown. The process 500 may be performed periodically, such as every 100 milliseconds (or 10 times / second), or at any other suitable frequency. Alternatively or in addition, the process 500 may be performed continuously.

[0205] Process 500 may begin in block 502, which may be transitioned to when therapy is initiated or when a set point is changed while therapy is being delivered. In block 502, process 500 compares wound pressure to a set point, which may be determined as explained below. For example, process 500 may subtract wound pressure from the set point, or vice versa. If the wound pressure is below the set point, process 500 may transition to block 504. Conversely, if the wound pressure exceeds or equals the set point, process 500 may transition to block 506.

[0206] In block 504 (Pressure Ramp Up), the process 500 may increment the pump ramp set point by an amount that depends on the compression setting, which is explained below. The vacuum pump will then attempt to pull down (or make more negative) the wound pressure to reach the current value of the pump ramp set point. For example, a suitable pump drive signal (e.g., a voltage or current signal) may be generated and supplied to the pump motor to increase the speed of the pump motor to achieve wound pull-down. For efficiency purposes, the pump motor may be driven using PWM or any other suitable method. The process 500 may continue to increment the pump ramp set point until it reaches a set point selected by the user. When the wound pressure has almost reached or reached the set point, the process 500 may transition to block 508, which may correspond to the pressure at which a steady state under the wound dressing is reached. For example, when the wound pressure is within a ramp-up threshold pressure of the set point, such as within 2 mmHg of the set point or within any other suitable value, the process 500 may transition to block 508. In some embodiments, the pump ramp set point may be adaptively set to a higher negative pressure than the set point. For example, as explained below, the device may detect the presence of one or more leaks that result in a higher level of flow. Because this results in a loss of pressure at the wound, the device may compensate for this pressure loss by increasing the pump ramp set point beyond the set point. For example, the device may set the pump ramp set point to 1%, 2%, 5%, etc. In some embodiments, the pump ramp set point may be adaptively set to a lower negative pressure (or a larger positive pressure) than the set point.

[0207] In block 506 (Pressure Ramp Down), the process 500 may set the pump ramp set point to a user selected set point (or another set point as explained above). The process 500 may deactivate the pump to allow the wound pressure to decay, e.g., due to one or more leaks in the fluid flow path, to reach or nearly reach the set point. This may be performed according to a compression setting, e.g., deactivating the pump for a first period of time and then activating the pump for a second period of time such that the pressure at the wound increases according to the compression setting.

[0208] Self-contained wound dressing

[0209] In certain embodiments, NPWT may be delivered via a self-contained wound dressing (e.g., PICO® sold by Smith & Nephew). TM Wound dressing) is applied to the wound. Figure 5A-B illustrates an embodiment of a negative pressure wound therapy system 10 using a wound dressing 100 in conjunction with a fluid connector 110. Here, the fluid connector 110 may include an elongated conduit, more preferably a bridge 120 having a proximal end 130 and a distal end 140, and an applicator 180 at the distal end 140 of the bridge 120. An optional connector 160 is preferably disposed at the proximal end 130 of the bridge 120. A cap 170 may be provided with the system (and in some cases may be attached to the connector 160 as shown). The cap 170 may be used to prevent fluid from leaking out of the proximal end 130. The system 10 may include a negative pressure source, such as a pump or negative pressure unit 150 capable of supplying negative pressure. The pump may include a tank or other container for storing wound exudate and other fluids that may be removed from the wound. The tank or container may also be provided separate from the pump. In, for example Figure 5A-5B In some embodiments shown, pump 150 may be a tankless pump, such as the PICO pump sold by Smith & Nephew. TM Pump. The pump 150 may be connected to the coupling 160 via a tube 190, or the pump 150 may be connected directly to the coupling 160 or directly to the bridge 120. In use, the dressing 100 is placed on a properly prepared wound, which in some cases may be filled with a wound packing material, such as foam or gauze. The applicator 180 of the fluid connector 110 has a sealing surface that is placed above the orifice of the dressing 100 and seals to the top surface of the dressing 100. Before, during, or after the fluid connector 110 is connected to the dressing 100, the pump 150 is connected to the coupling 160 via a tube 190, or directly to the coupling 160 or the bridge 120. The pump is then activated, thereby supplying negative pressure to the wound. Negative pressure may be applied until the desired level of wound healing is reached.

[0210] like Fig. 6A As shown in , the fluid connector 110 preferably includes an enlarged distal end, or head 140 in fluid communication with the dressing 100, which will be described in more detail below. In one embodiment, the enlarged distal end is circular or annular. The head 140 is shown here as being positioned near the edge of the dressing 100, but may be positioned at any position on the dressing. For example, some embodiments may provide a centered or off-center position that is not on or near the edge or corner of the dressing 100. In some embodiments, the dressing 10 may include two or more fluid connectors 110, each including one or more heads 140 in fluid communication therewith. In a preferred embodiment, the head 140 may measure 30 mm along its widest edge. The head 140 forms at least a portion of the applicator 180 described above, which is configured to seal the top surface of the wound dressing.

[0211] Figure 6B The diagram shows a process similar to Figure 5BA wound dressing 100 and a cross section of a fluid connector 110 of a wound dressing 10 shown in and described in International Patent Publication WO2013175306 A2, which is incorporated herein by reference in its entirety. The wound dressing 100 may be any combination of features of any wound dressing embodiment disclosed herein or any number of wound dressing embodiments disclosed herein, which may be located above a wound site to be treated. The dressing 100 may be placed so as to form a sealed cavity above the wound site. In a preferred embodiment, the dressing 100 includes a top or cover layer, or a backing layer 220 attached to an optional wound contact layer 222, both of which are described in more detail below. The two layers 220, 222 are preferably joined or sealed together to define an interior space or chamber. The interior space or chamber may include additional structures that may be suitable for distributing or transmitting negative pressure, storing wound exudate and other fluids removed from the wound, and other functions, which will be explained in more detail below. Examples of such structures described below include a transmission layer 226 and an absorption layer 221.

[0212] As used herein, an upper layer, top layer or upper layer refers to the layer furthest from the surface of the skin or wound when the dressing is in use and positioned over a wound. Thus, a lower surface, lower layer, bottom layer or underlying layer refers to the layer closest to the surface of the skin or wound when the dressing is in use and positioned over a wound.

[0213] like Figure 6B As shown, the wound contact layer 222 may be a polyurethane layer or a polyethylene layer or other flexible layer, which is perforated, for example, by a heat-seal process, a laser ablation process, an ultrasonic process, or in some other way, or is otherwise made permeable to liquids and gases. The wound contact layer 222 has a lower surface 224 and an upper surface 223. The perforations 225 preferably include through holes in the wound contact layer 222, which allow fluid to flow through the layer 222. The wound contact layer 222 helps prevent tissue from growing inwardly into other materials of the wound dressing. Preferably, the perforations are small enough to meet this requirement while still allowing fluid to flow therethrough. For example, perforations formed as gaps or holes with a size ranging from 0.025 mm to 1.2 mm are considered small enough to help prevent tissue from growing inwardly into the wound dressing while allowing wound exudate to flow into the dressing. In some configurations, the wound contact layer 222 can help maintain the integrity of the entire dressing 100 while also creating an airtight seal around the absorbent pad to maintain negative pressure at the wound.

[0214] Some embodiments of the wound contact layer 222 may also serve as a carrier for optional lower and upper adhesive layers (not shown). For example, a lower pressure sensitive adhesive may be provided on the lower surface 224 of the wound dressing 100, while an upper pressure sensitive adhesive layer may be provided on the upper surface 223 of the wound contact layer. The pressure sensitive adhesive may be a silicone, hot melt, hydrocolloid, or acrylic based adhesive or other such adhesive, and may be formed on both sides of the wound contact layer, or optionally formed on a selected one of the two sides of the wound contact layer, or formed on neither side. When a lower pressure sensitive adhesive layer is used, it may help to adhere the wound dressing 100 to the skin around the wound site. In some embodiments, the wound contact layer may include a perforated polyurethane film. The lower surface of the film may be provided with a silicone pressure sensitive adhesive, and the upper surface may be provided with an acrylic pressure sensitive adhesive, which may help the dressing maintain its integrity. In some embodiments, the polyurethane film layer may be provided with adhesive layers on its upper and lower surfaces, and all three layers may be perforated together.

[0215] A layer 226 of porous material may be located above the wound contact layer 222. This porous layer or transmission layer 226 allows fluid transport, including liquids and gases, away from the wound site into the upper layers of the wound dressing. In particular, the transmission layer 226 preferably ensures that open air channels can be maintained to transmit negative pressure over the wound area even when the absorbent layer has absorbed a large amount of exudate. The layer 226 should preferably remain open at typical pressures that will be applied during negative pressure wound therapy as described above so that the entire wound site is subjected to a balanced negative pressure. The layer 226 may be formed of a material having a three-dimensional structure. For example, a knitted or woven spacer fabric (e.g., Baltex 7970 weft-knitted polyester) or a non-woven fabric may be used.

[0216] In some embodiments, the transmission layer 226 comprises a 3D polyester spacer fabric layer comprising a top layer (i.e., the layer away from the wound bed in use), the top layer is 84 / 144 textured polyester, and a bottom layer (i.e., the layer close to the wound bed in use), the bottom layer is 10 denier flat polyester, and a third layer sandwiched between the two layers, the third layer is a region defined by a knitted polyester viscose, cellulose or similar monofilament fiber. Of course, other materials and other linear mass densities of fibers can be used.

[0217] Although reference is made throughout this disclosure to monofilament fibers, it will be appreciated that multiple strand alternatives may of course be used.Thus, the top spacer fabric has a greater number of filaments in the yarn used to form it than the filaments constituting the yarn used to form the bottom spacer fabric layer.

[0218] This difference between the number of filaments in the spaced apart layers helps to control the flow of moisture through the transmission layer. Specifically, by having a greater number of filaments in the top layer, i.e., the top layer is made of a yarn having more filaments than the yarn used for the bottom layer, liquid tends to be wicked more along the top layer than the bottom layer. In use, this difference tends to draw liquid away from the wound bed and into the central area of ​​the dressing where the absorbent layer 221 helps to lock liquid away or wick it forward towards the cover layer where it can transpire.

[0219] Preferably, to improve liquid flow through the transmission layer 226 (i.e., perpendicular to the channel area formed between the top and bottom spacer layers), the 3D fabric may be treated with a dry cleaning agent (e.g., but not limited to, Perchloroethylene) to help remove any manufacturing products, such as previously used mineral oils, fats and / or waxes, which may interfere with the hydrophilic capabilities of the transmission layer. In some embodiments, an additional manufacturing step may then be performed in which the 3D spacer fabric is washed in a hydrophilic agent (e.g., but not limited to, Feran Ice 30 g / l available from Rudolph Group). This process step helps ensure that the surface tension on the material is very low so that liquids such as water can enter the fabric once it contacts the 3D knitted fabric. This also helps control the flow of liquid insult components of any exudate.

[0220] The absorbent material layer 221 is disposed above the transmission layer 226. The absorbent material, including foam or nonwoven natural or synthetic material, and optionally including superabsorbent material, forms a reservoir for fluids (particularly liquids) removed from the wound site. In some embodiments, layer 10 may also help absorb fluids toward the backing layer 220.

[0221] The material of the absorbent layer 221 may also prevent liquid collected in the wound dressing 100 from flowing freely within the dressing, and is preferably used to contain any liquid collected within the dressing. The absorbent layer 221 also helps to distribute the fluid throughout the layer via wicking action so that the fluid is absorbed from the wound site and stored throughout the absorbent layer. This helps to prevent accumulation in areas of the absorbent layer. The capacity of the absorbent material must be sufficient to manage the flow rate of exudate from the wound when negative pressure is applied. Since in use, the absorbent layer experiences negative pressure, the material of the absorbent layer is selected to absorb liquid under such circumstances. There are many materials that can absorb liquid under negative pressure, such as superabsorbent materials. The absorbent layer 221 can generally be made of ALLEVYN TM Foam, Freudenberg 114-224-4 and / or Chem-Posite TM 11C-450. In some embodiments, the absorbent layer 221 may include a composite comprising superabsorbent powder, fibrous material such as cellulose, and binding fibers. In a preferred embodiment, the composite is an air-laid thermally bonded composite.

[0222] In some embodiments, the absorbent layer 221 is a nonwoven cellulose fiber layer having superabsorbent material in the form of dry particles dispersed throughout. The use of cellulose fibers introduces a fast wicking element that helps to quickly and evenly distribute the liquid absorbed by the dressing. The juxtaposition of multiple strands of fibers results in a strong capillary action in the fiber pad, which helps to distribute the liquid. In this way, the superabsorbent material is effectively supplied with liquid. The wicking action also helps to bring the liquid into contact with the upper cover layer to help increase the transpiration rate of the dressing.

[0223] An orifice, hole or aperture 227 is preferably provided in the backing layer 220 to allow negative pressure to be applied to the dressing 100. The fluid connector 110 is preferably attached or sealed to the top of the backing layer 220 over the aperture 227 created in the dressing 100 and transmits negative pressure via the aperture 227. A length of tubing may be coupled to the fluid connector 110 at a first end and to a pump unit (not shown) at a second end to allow fluid to be pumped out of the dressing. In the case where the fluid connector is adhered to the top layer of the wound dressing, a length of tubing may be coupled to the first end of the fluid connector so that the tubing or conduit extends away from the fluid connector parallel to or substantially to the top surface of the dressing. The fluid connector 110 may be adhered and sealed to the backing layer 220 using an adhesive such as an acrylic, cyanoacrylate, epoxy, UV curable or hot melt adhesive. The fluid connector 110 may be formed of a soft polymer such as polyethylene, polyvinyl chloride, silicone or polyurethane having a Shore A hardness of 30 to 90. In some embodiments, fluid connector 110 may be made of a soft or conformable material.

[0224] Preferably, the absorbent layer 221 includes at least one through hole 228 positioned so as to overlie the fluid connector 110. In some embodiments, the through hole 228 may be the same size as the opening 227 in the backing layer, or may be larger or smaller. Figure 6B As shown in , a single through hole can be used to create an opening located below the fluid connector 110. It will be appreciated that multiple openings can be used instead. In addition, if more than one port is used according to certain embodiments of the present disclosure, one or more openings can be created in the absorbent layer and the shielding layer in registration with each corresponding fluid connector. Although not required for certain embodiments of the present disclosure, the use of through holes in the superabsorbent layer can provide a fluid flow path that remains unobstructed, especially when the absorbent layer is close to saturation.

[0225] like Figure 6BAs shown in , the orifice or through hole 228 is preferably provided in the absorbent layer 221 below the aperture 227 so that the aperture is directly connected to the transmission layer 226. This allows the negative pressure applied to the fluid connector 110 to communicate with the transmission layer 226 without passing through the absorbent layer 221. This ensures that the negative pressure applied to the wound site is not inhibited by the absorbent layer when the absorbent layer absorbs wound exudate. In other embodiments, there may be no orifice provided in the absorbent layer 221, or a plurality of orifices located below the aperture 227 may be provided. In other alternative embodiments, an additional layer (e.g., another transmission layer or shielding layer as described in International Patent Publication WO2014020440, which is incorporated herein by reference in its entirety) may be provided above the absorbent layer 221 and below the backing layer 220.

[0226] The backing layer 220 is preferably impermeable to gases, but permeable to water vapor, and may extend across the width of the wound dressing 100. The backing layer 220, which may be, for example, a polyurethane film (e.g., Elastollan SP9109) with a pressure sensitive adhesive on one side, is impermeable to gases, and this layer is therefore used to cover the wound and seal the wound cavity, over which the wound dressing is placed. In this way, an effective chamber is created between the backing layer 220 and the wound site, in which a negative pressure may be established. For example, by adhesive or welding techniques, the backing layer 220 may be sealed to the wound contact layer 222, preferably in a border region around the circumference of the dressing, ensuring that no air is sucked in via the border region. The backing layer 220 protects the wound from external bacterial contamination (bacterial barrier), and allows liquid from wound exudate to be transmitted through this layer and evaporate from the outer surface of the film. The backing layer 220 preferably comprises two layers; a polyurethane film and an adhesive pattern applied to the film. The polyurethane film is preferably permeable to water vapor and may be made of a material that has an increased water permeability when wet. In some embodiments, the moisture permeability of the backing layer increases when the backing layer becomes wet. The moisture permeability of the wet backing layer may be up to about ten times greater than the moisture permeability of the dry backing layer.

[0227] The absorbent layer 221 may have a larger area than the transmission layer 226 such that the absorbent layer covers the edges of the transmission layer 226, thereby ensuring that the transmission layer does not contact the backing layer 220. This provides an outer channel of the absorbent layer 221 which is in direct contact with the wound contact layer 222, which helps exudate to be absorbed into the absorbent layer more quickly. Furthermore, this outer channel ensures that no liquid can pool around the periphery of the wound cavity, which could otherwise penetrate through the seal around the periphery of the dressing, causing a leak to form. Figure 6A-6B As shown in , the absorbent layer 221 can define a perimeter that is smaller than the perimeter of the backing layer 220 such that a demarcation or border region is defined between an edge of the absorbent layer 221 and an edge of the backing layer 220 .

[0228] like Figure 6BAs shown in , one embodiment of the wound dressing 100 includes an orifice 228 in the absorbent layer 221 located below the fluid connector 110. In use, for example when negative pressure is applied to the dressing 100, the wound-facing portion of the fluid connector can thus contact the transmission layer 226, which can thus help transmit the negative pressure to the wound site even when the absorbent layer 221 is filled with wound fluid. Some embodiments may have the backing layer 220 at least partially adhered to the transmission layer 226. In some embodiments, the orifice 228 is at least 1-2 mm larger than the diameter of the wound-facing portion or pore 227 of the fluid connector 110.

[0229] Specifically, for embodiments having a single fluid connector 110 and through hole, it may be preferred that the fluid connector 110 and through hole be located such as Fig. 6A Such a position can allow the dressing 100 to be positioned on the patient so that the fluid connector 110 is elevated relative to the rest of the dressing 100. So positioned, the fluid connector 110 and the filter 214 are less likely to come into contact with wound fluids that could prematurely occlude the filter 214, thereby compromising the transmission of negative pressure to the wound site.

[0230] Turning now to the fluid connector 110, the preferred embodiment includes a sealing surface 216, a bridge 211 having a proximal end 130 and a distal end 140 (corresponding to Figure 5A-5B120 in the sealing surface), and the filter 214. The sealing surface 216 preferably forms the applicator described above, which is sealed to the top surface of the wound dressing. In some embodiments, the bottom layer of the fluid connector 110 may include the sealing surface 216. The fluid connector 110 may also include an upper surface vertically spaced apart from the sealing surface 216, and in some embodiments, the sealing surface is defined by a separate upper layer of the fluid connector. In other embodiments, the upper surface and the lower surface may be formed by the same material piece. In some embodiments, the sealing surface 216 may include at least one orifice 229 therein to communicate with the wound dressing. In some embodiments, the filter 214 may be positioned to pass through the opening 229 in the sealing surface, and may span the entire opening 229. The sealing surface 216 may be configured to seal the fluid connector to the cover layer of the wound dressing, and may include an adhesive or welding. In some embodiments, the sealing surface 216 may be placed above the aperture in the cover layer, wherein the optional spacing element 215 is configured to create a gap between the filter 214 and the transmission layer 226. In other embodiments, the sealing surface 216 may be positioned over the apertures in the cover layer and the apertures in the absorbent layer 220 to allow the fluid connector 110 to provide air flow through the transmission layer 226. In some embodiments, the bridge 211 may include a first fluid passage 212 in communication with a source of negative pressure, the first fluid passage 212 comprising a porous material, such as a 3D knitted material, which may be the same as or different from the porous layer 226 described above. The bridge 211 is preferably encapsulated by at least one flexible membrane layer 208, 210 having a proximal end and a distal end, and is configured to surround the first fluid passage 212, the distal end of the flexible membrane being connected to the sealing surface 216. The filter 214 is configured to substantially prevent wound exudate from entering the bridge, and the spacer element 215 is configured to prevent the fluid connector from contacting the transmission layer 226. These elements will be described in more detail below.

[0231] Some embodiments may also include an optional second fluid pathway positioned above the first fluid pathway 212. For example, some embodiments may provide an air leak that may be disposed at a proximal end of the top layer configured to provide an air path into the first fluid pathway 212 and the dressing 100, similar to the suction adapter described in U.S. Patent No. 8,801,685, which is incorporated herein by reference in its entirety.

[0232] Preferably, the fluid pathway 212 is composed of a compliant material that is flexible and allows fluid to pass through it if the spacer is kinked or folded. Suitable materials for the fluid pathway 212 include, but are not limited to, foams, including open foams such as polyethylene or polyurethane foams, meshes, 3D knitted fabrics, nonwoven materials, and fluid channels. In some embodiments, the fluid pathway 212 may be composed of materials similar to those described above with respect to the transmission layer 226. Advantageously, such materials used in the fluid pathway 212 not only allow for greater patient comfort, but also provide greater kink resistance, such that the fluid pathway 212 is still able to transmit fluid from the wound toward the negative pressure source when kinked or bent.

[0233] In some embodiments, the fluid passage 212 can be made of a wicking fabric, such as a knitted or woven spacer fabric (e.g., a knitted polyester 3D fabric, Baltex or Gehring ) or nonwoven fabric. These selected materials are preferably suitable for guiding wound exudate away from the wound through the channel, and for transmitting negative pressure and / or exhaust air to the wound site, and can also give the fluid passage 212 a certain degree of anti-kink or occlusion. In some embodiments, the wicking fabric may have a three-dimensional structure, which may help wick fluid or transmit negative pressure in some cases. In certain embodiments including wicking fabrics, these materials remain open and can transmit negative pressure to the wound area at a typical pressure used in negative pressure therapy (e.g., between 40 and 150 mmHg). In some embodiments, the wicking fabric may include several material layers stacked or laminated on each other, which may be used in some cases to prevent the fluid passage 212 from collapsing under the application of negative pressure. In other embodiments, the wicking fabric used in the fluid passage 212 may be between 1.5 mm and 6 mm; more preferably, the wicking fabric may be 3 mm to 6 mm thick, and may include one or more independent layers of wicking fabric. In other embodiments, the fluid passage 212 may be 1.2 to 3 mm thick, and preferably thicker than 1.5 mm. Some embodiments (e.g., a suction adapter for a dressing that holds liquids such as wound exudate) may use a hydrophobic layer in the fluid pathway 212, and only gas may travel through the fluid pathway 212. Additionally, and as previously described, the materials used in the system are preferably compliant and soft, which may help avoid pressure ulcers and other complications that may result from the wound treatment system pressing against the patient's skin.

[0234] Preferably, the filter element 214 is impermeable to liquids, but is breathable, and is provided to act as a liquid barrier and ensure that no liquid can escape from the wound dressing 100. The filter element 214 may also act as a bacterial barrier. Typically, the pore size is 0.2 μm. Suitable materials for filter materials for the filter element 214 include 0.2 micron Gore from the MMT range TMExpanded PTFE, PALL Versapore TM 200R and Donaldson TM TX6628. Larger pore sizes may also be used, but these may require a secondary filter layer to ensure complete bioburden containment. Since wound fluids contain liquids, it is preferred but not necessary to use an oleophobic filter membrane, such as 1.0 micron MMT-332, before the 0.2 micron MMT-323. This prevents lipids from clogging the hydrophobic filter. The filter element may be attached or sealed to the port and / or cover membrane above the pore. For example, the filter element 214 may be molded into the fluid connector 110, or an adhesive (such as, but not limited to, a UV-cured adhesive) may be used to adhere to one or both of the top of the cover layer and the bottom of the suction adapter 110.

[0235] It should be understood that other types of materials can be used for the filter element 214. More generally, a microporous membrane can be used, which is a thin flat sheet of polymeric material, which contains billions of micropores. Depending on the membrane selected, these pores can range in size from 0.01 to greater than 10 microns. Microporous membranes come in two forms: hydrophilic (water filtering) and hydrophobic (water repellent). In some embodiments of the present disclosure, the filter element 214 includes a support layer and an acrylic copolymer membrane formed on the support layer. Preferably, the wound dressing 100 according to certain embodiments of the present disclosure uses a microporous hydrophobic membrane (MHM). Many polymers can be used to form the MHM. For example, the MHM can be formed from one or more of PTFE, polypropylene, PVDF, and acrylic copolymers. All of these optional polymers can be treated to obtain specific surface features that can be hydrophobic and oleophobic. Therefore, these will repel liquids with low surface tension, such as multivitamin infusions, lipids, surfactants, oils, and organic solvents.

[0236] MHMs block liquids while allowing air to flow through the membrane. They are also highly efficient air filters that eliminate potentially infectious aerosols or particles. Single-piece MHMs are known to act as an alternative to mechanical valves or vents. Therefore, configuring MHMs reduces product assembly costs to improve patient profitability and cost / benefit ratios.

[0237] The filter element 214 may also include an odor absorbing material, such as activated carbon, carbon fiber cloth, or VitecCarbotec-RT Q2003073 foam, etc. For example, the odor absorbing material may form a layer of the filter element 214, or may be sandwiched between the microporous hydrophobic membranes of the filter element. The filter element 214 thus allows gas to escape through the pores. However, the dressing contains liquids, particles, and pathogens.

[0238] The wound dressing 100 may include a spacing element 215 in conjunction with the fluid connector 110 and the filter 214. In addition to this spacing element 215, the fluid connector 110 and the filter 214 may be supported without being in direct contact with the absorbent layer 220 and / or the transmission layer 226. The absorbent layer 220 may also serve as an additional spacing element to keep the filter 214 from contacting the transmission layer 226. Thus, with this configuration, contact of the filter 214 with the transmission layer 226 and wound fluids may be minimized during use.

[0239] Similar to the embodiments of wound dressings described above, some wound dressings include a perforated wound contact layer with a silicone adhesive on the skin contacting side and an acrylic adhesive on the back side. A transmission layer or 3D spacer fabric pad is located above the boundary layer. An absorbent layer is located above the transmission layer. The absorbent layer may include a superabsorbent nonwoven (NW) pad. The absorbent layer may cross the transmission layer at the periphery by about 5 mm. The absorbent layer may have an orifice or through hole toward one end. The orifice may be about 10 mm in diameter. A backing layer is located on the transmission layer and the absorbent layer. The backing layer may be a high moisture vapor transmission rate (MVTR) film coated with a pattern of acrylic adhesive. The high MVTR film and the wound contact layer encapsulate the transmission layer and the absorbent layer, resulting in a peripheral boundary of about 20 mm. The backing layer may have a 10 mm orifice, which overlies the orifice in the absorbent layer. A fluid connector may be attached to the orifice, the fluid connector comprising a liquid-impermeable, breathable semipermeable membrane (SPM) or filter overlying the aforementioned orifice.

[0240] Treatment of abdominal wounds

[0241] Go to Figure 7 , other wound types (e.g., larger abdominal wounds) are treated with negative pressure in certain embodiments using a negative pressure therapy system 101 as schematically shown herein. In this embodiment, a wound site 106 (shown here as an abdominal wound site) may benefit from treatment with negative pressure. Such an abdominal wound site may be the result of an accident or surgical intervention, for example. In some cases, medical conditions such as abdominal compartment syndrome, abdominal hypertension, sepsis, or fluid edema may require abdominal decompression through a surgical incision in the abdominal wall to expose the peritoneal cavity, after which the opening may need to remain in an open, accessible state until the condition resolves. Other conditions may also require that the opening (particularly in the abdominal cavity) remain open, for example, if multiple surgical procedures are required (which may be prone to trauma), or if there are signs of a clinical condition such as peritonitis or necrotizing fasciitis.

[0242] In the case of a wound, particularly in the abdomen, it is necessary to manage possible complications associated with exposure of organs and peritoneal spaces, whether the wound is kept open or closed. Preferably, the treatment applied using negative pressure can be targeted to minimize the risk of infection while promoting tissue vitality and removing harmful substances from the wound site. It has been found that applying reduced pressure or negative pressure to the wound site generally promotes faster healing, increased blood flow, reduced bacterial load, increased granulation tissue formation rate, stimulated fibroblast proliferation, stimulated endothelial cell proliferation, closed chronic open wounds, inhibited burn penetration, and / or enhanced flap and graft attachment, etc. It has also been reported that wounds that have shown a positive response to treatment by applying negative pressure include infected open wounds, decubitus ulcers, dehiscence incisions, partial thickness burns, and various lesions of attached flaps or grafts. Therefore, applying negative pressure to the wound site 106 may be beneficial to the patient.

[0243] Therefore, certain embodiments provide for placing a wound contact layer 105 above a wound site 106. A wound contact layer may also be referred to as an organ protection layer and / or a tissue protection layer. Preferably, the wound contact layer 105 may be a thin, flexible material that is not closely attached to the wound site or exposed internal organs. For example, polymers such as polyurethane, polyethylene, polytetrafluoroethylene or blends thereof may be used. In one embodiment, the wound contact layer is permeable. For example, the wound contact layer 105 may be provided with openings, such as holes, slits or channels, to allow removal of fluid from the wound site 106 or transfer of negative pressure to the wound site 106. Additional embodiments of the wound contact layer 105 are described in further detail below.

[0244] Certain embodiments of the negative pressure therapy system 101 may also use a porous wound filler 103, which may be arranged above the wound contact layer 105. The pad 103 may be made of a porous material (e.g., foam) that is soft, resilient, and generally conforms to the wound site 106. Such foams may include open-cell and reticular foams made of, for example, polymers. Suitable foams include foams composed of, for example, polyurethane, silicone, and polyvinyl alcohol. Preferably, when negative pressure is applied to the wound, the pad 103 can guide wound exudate and other fluids through itself. Some pads 103 may include preformed channels or openings for such purposes. In certain embodiments, the pad 103 may have a thickness between about one inch and about two inches. The pad may also have a length between about 16 and 17 inches, and a width between about 11 and 12 inches. In other embodiments, the thickness, width, and / or length may have other suitable values. Other embodiments of wound fillers that may be used as an alternative or additional to the pad 103 are discussed in further detail below.

[0245] Preferably, a drape 107 is used to seal the wound site 106. The drape 107 may be at least partially liquid impermeable so that at least partial negative pressure can be maintained at the wound site. Suitable materials for the drape 107 include, but are not limited to, synthetic polymer materials that do not significantly absorb aqueous fluids, including polyolefins such as polyethylene and polypropylene, polyurethanes, polysiloxanes, polyamides, polyesters and other copolymers and mixtures thereof. The materials used in the drape may be hydrophobic or hydrophilic. Examples of suitable materials include those available from DeRoyal and available from Smith & Nephew To aid patient comfort and avoid skin maceration, the drape is at least partially breathable in some embodiments, allowing water vapor to pass through without being collected under the dressing. An adhesive layer may be provided on at least a portion of the underside of the drape 107 to secure the drape to the patient's skin, but some embodiments may use a separate adhesive or adhesive tape instead. Optionally, a release layer may be provided on the adhesive layer to protect it prior to use and to facilitate handling of the drape 107; in some embodiments, the release layer may be composed of multiple sections.

[0246] The negative pressure system 101 can be connected to a negative pressure source, such as a pump 114. An example of a suitable pump is the Renasys EZ pump available from Smith & Nephew. The drape 107 can be connected to the negative pressure source 114 via a conduit 112. The conduit 112 can be connected to a port 113 located above the hole 109 in the drape 107, or the conduit 112 can be connected directly through the hole 109 without using a port. In another alternative, the conduit can pass from under the drape and extend from one side of the drape. U.S. Patent No. 7,524,315 discloses other similar aspects of the negative pressure system, and its entire contents are incorporated herein by reference and should be considered a part of this specification.

[0247] In many applications, a container or other storage unit 115 may be interposed between the negative pressure source 114 and the conduit 112 to allow wound exudate and other fluids removed from the wound site to be stored without entering the negative pressure source. Certain types of negative pressure sources (e.g., peristaltic pumps) may also allow the container 115 to be placed after the pump 114. Some embodiments may also use filters to prevent fluids, aerosols, and other microbial contaminants from leaving the container 115 and / or entering the negative pressure source 114. Other embodiments may also include a shutoff valve or enclosed hydrophobic and / or oleophobic filter in the container to prevent overflow; other embodiments may include a sensing device, such as a capacitive sensor or other liquid level detector, which is used to stop or shut down the negative pressure source if the liquid level in the container is close to capacity. At the pump exhaust port, an odor filter, such as an activated carbon canister, may also be preferably provided.

[0248] Euler Video Zooms in on Wound Monitoring and NPWT Therapy

[0249] A new technique for analyzing small changes in pixels over time has been developed using a technique called "Eulerian Video Magnification" (EVM). EVM can be used to amplify these extremely small changes in pixels over time, thus allowing previously undetectable changes to be detected. For example, EVM can be applied to standard video, such as video acquired by an optical camera. Small visual changes in the state of the object and / or person being recorded can then be amplified by the EVM and thus detected. For example, EVM can detect blood flow or breathing under the skin of a newborn baby, for example. Additional details about EVM are provided in an article by Wu et al. published by the Massachusetts Institute of Technology, entitled "Eulerian Video Magnification for Revealing Subtle Changes in the World," which is incorporated herein by reference in its entirety.

[0250] EVM is used to amplify subtle changes in video (e.g., pixels) at any spatial location over time. Such subtle changes may not be visible to the naked eye, and therefore, EVM allows detection of subtle phenomena that are undetectable under normal observation and monitoring. Such video can be acquired by any suitable means and is not limited to video acquired within the visible spectrum. For example, the video can be acquired by: a camera, a charge coupled device (CCD), an oxygen saturation (spO2) detector, magnetic resonance imaging, x-ray imaging, infrared imaging, or any form of video data acquisition over time. The amplified changes in pixel values ​​may be the result of changes due to changes in color, motion, or any other suitable changes depending on the type of video. For example, a video of spO2 measurements in a particular area can be output as a value, such as a color, and therefore, EVM applied to this video can detect subtle changes in spO2. As mentioned above, additional details about EVM are provided in the Massachusetts Institute of Technology article by Wu et al., “Eulerian Video Magnification for Revealing Subtle Changes in the World.”

[0251] As described by Wu et al., spatial and temporal processing can be used to emphasize small temporal changes in video. An embodiment of this process is shown in FIG3. In brief, the EVM system 300 first decomposes 304 the input video sequence 302 into different spatial frequency bands 306 and applies the same temporal filter to all bands 308. The filtered spatial bands 310 are then amplified by a given factor α 312, added to the original signal 314, and compressed to generate the output video 316.

[0252] As described by Wu, first, the video sequence is decomposed into different spatial frequency bands. These bands may be amplified differently because (a) they may exhibit different signal-to-noise ratios, or (b) they may contain spatial frequencies for which the linear approximation for motion amplification described later is not applicable. In the latter case, the amplification of these bands can be reduced to suppress artifacts. When the goal of the spatial processing is simply to increase the temporal signal-to-noise ratio by pooling multiple pixels, the video frames can be subjected to spatial low-pass filtering and downsampling for computational efficiency. However, in the general case, a full Laplacian pyramid [Burt and Adelson 1983] can be performed, followed by temporal processing on each spatial band. The time series corresponding to the values ​​of the pixels in the band can be considered, and a bandpass filter can be applied to extract the frequency band of interest. For example, if we wish to amplify pulses, we can choose frequencies in the range of 0.4-4 Hz, corresponding to 24-240 beats / minute. If we can extract the pulse rate, we can use a narrow band around this value. The temporal processing is uniform for all spatial levels and for all pixels within each level. We then multiply the extracted bandpass signal by the amplification factor. This factor can be specified by the user and can be automatically attenuated according to the guidelines described below. Possible temporal filters are also discussed below. Next, we add the amplified signal to the original signal and compress the spatial pyramid to obtain the final output. Since natural video is smooth both spatially and temporally, and since the filtering is performed uniformly across pixels, the method we use implicitly preserves the spatiotemporal coherence of the result.

[0253] To explain the relationship between temporal processing and motion amplification, we consider the simple case of a 1D signal that undergoes translational motion. The analysis generalizes directly to local translational motion in 2D. Let I(x; t) denote the image intensity at position x and time t. Since the image undergoes translational motion, we can express the observed intensity with respect to a displacement function δ(t) such that I(x; t) = f(x + δ(t)) and I(x; 0) = f(x). The goal of motion amplification is to synthesize a signal for some amplification factor α.

[0254] Assuming that the image can be approximated by a first-order Taylor series expansion, we write the image f(x+δ(t)) at time t with respect to x as

[0255]

[0256] Let B(x; t) be the result of applying a broadband temporal bandpass filter to I(x; t) at each location x (picking up anything other than f(x) in the equation above). Now, we assume that the motion signal (t) lies within the passband of the temporal bandpass filter (we will relax this assumption later). We then get

[0257]

[0258] Then, in our process, we amplify this bandpass signal and add it to I(x; t), producing the processed signal

[0259]

[0260] Combining the previous equations, we now get

[0261]

[0262] Assuming a first-order Taylor expansion for the amplified larger perturbation (1+α)δ(t), we can relate the amplification of the time-bandpass signal to motion amplification. The processed output is simply

[0263]

[0264] This shows that this process amplifies the motion - the spatial displacement δ(t) of the local image f(x) at time t, has been amplified to a magnitude of (1+α). For low frequency cosine waves and relatively small displacements (t), the first-order Taylor series expansion serves as a good approximation of the translation signal at time t+1. When this is done by intensifying the temporal signal and adding it to I(x; t), we approximate a wave that is translated by (1+α)δ. For rapidly changing image functions (i.e., high spatial frequencies) f(x), the first-order Taylor series approximation becomes inaccurate for large perturbations of 1+αδ(t), which increase both with greater amplification and the motion δ(t).

[0265] We can derive guidelines for how large the motion amplification factor α can be, given an observed motion δ(t) as a function of spatial frequency ω. For a processed signal I(x,t) that is roughly equal to the true amplified motion I(x,t), we seek the following conditions to hold:

[0266]

[0267] Further rearrangement is done by the cosine addition law and using the following approximation:

[0268] cos(βωδ(t))≈1

[0269] sin(βωδ(t))≈βδ(t)ω

[0270] The following guidelines are generated:

[0271]

[0272] This guideline provides the largest motion magnification factor α that is compatible with accurate motion magnification for a given video motion δ(t) and image structure spatial wavelength λ. In some videos, violating the approximation limit may be perceptually preferred, and we keep the λ cutoff as a user-modifiable parameter in the multiscale process.

[0273] In some embodiments, to process an input video via Euler video upscaling, the user needs to complete four steps: (1) select a temporal bandpass filter; (2) select an upscaling factor α; (3) select a spatial cutoff frequency (specified by the spatial wavelength λc) above which an attenuated version of α is used; and (4) select an attenuated form of α that forces α to zero, or linearly scales α to zero, for all λ<λc. In some cases, the frequency band of interest may be selected automatically, but it is often important for the user to be able to control the frequency band that corresponds to their application. In real-time applications, the upscaling factor and cutoff frequency may all be customizable by the user.

[0274] Those skilled in the art will appreciate that the term "color" as used herein in this section and throughout this specification may refer to more than just a spectrum. The word "color" may sometimes be used colloquially to identify a spectral frequency range (which may or may not be within the visible light range). Those skilled in the art will further appreciate that, in embodiments, the techniques described herein may also work without the use of an EVM, for example, by detecting changes in green / red. However, the sensitivity of such a system without an EVM may be significantly reduced.

[0275] Of particular interest for the assessment of wounds, in some embodiments, Euler video magnification can be used to amplify subtle changes in pixel values ​​associated with color using video captured from a CCD camera or RGB color detector. In embodiments, the camera or RGB color detector can be combined with one or more standard LEDs to illuminate the wound for visualization. For example, within a patch of skin or wound bed, color changes can indicate good blood flow. For example, detecting values ​​in the red spectrum by color can indicate blood flow, so if the difference between the peaks and valleys of the color is small, it suggests that there is not a lot of blood flow. Conversely, if the difference between the peaks and valleys is relatively high, this can indicate good blood flow in the tissue area.

[0276] Additionally, if the value is not so red, there may be insufficient oxygen. In embodiments, color may also be used to generate a blood oxygen indication (or with a light source modified to sense SP02 directly) to minimize the likelihood of capillary damage and act as an alarm if exsanguination occurs, potentially mitigating potential hazards that may be caused by NPWT. In some embodiments, the EVM may be used on the skin near a wound to monitor movement of the adjacent skin, thus identifying if blood pulsation is heading to an area of ​​concern. Advantageously, absolute values ​​need not be monitored to identify potential problems within a wound or tissue, but rather differences in monitoring values ​​may be sufficient.

[0277] Fig. 9 An embodiment of a NPWT system 1000 incorporating an EVM is depicted. The dressing 1002 is similar to the previously described Figure 1 and Figure 5A-7 A dressing is disclosed which may include at least one sensor 1004. In embodiments, the dressing may contain one sensor, two sensors, three sensors, four sensors, five sensors, at least about 10 sensors, at least about 20 sensors, or more than 20 sensors. The sensor may be placed in any layer of the dressing, for example, a wound contact layer, an absorbent layer, a transmission layer, or a cover layer. The sensors may be distributed between multiple layers, such as in a wound contact layer and an absorbent layer, in a wound contact layer and a cover layer, and so on. The sensors may be in the form of an array. In embodiments, the sensors may be separated by air gaps or coated with a barrier layer that is transparent to the wavelength to be used. Additional layers, such as polyurethane foam, may be used behind the sensor to provide cushioning when the patient leans on the sensor to minimize the pressure focus created by the sensor. The sensor may also be encapsulated in silicone or polyurethane.

[0278] In embodiments, the sensor may collect information such as pH, temperature, light, conductivity, impedance, capacitance, or other characteristics of the wound. In some embodiments, the sensor may provide information about blood flow, moisture or dryness of the wound, lactic acid levels, or other characteristics of the wound. In some embodiments, all manner of sensors may be incorporated into the system, and they may be configured to measure parameters such as temperature, pH, oxygen, carbon dioxide, conductivity, inductance, lactate, matrix metalloproteinases, growth factors, light absorption and reflection including at infrared and UV frequencies and fluorescence, infection (bacterial load levels and bacterial types), or other characteristics of the wound environment. In certain embodiments, an ultrasonic sensor with or without a transducer may be used.

[0279] In some embodiments, thermistors or thermocouples may be used in place of the RGB sensor / CCD and light source described above. A grid or matrix of such sensors may be mounted and compactly coupled to the tissue. These may be used with other sensors (e.g., optical or EEG / ECG) to allow separation of heart rate from ambient temperature noise (i.e., identifying temperature changes occurring at the heart pulse rate).

[0280] In embodiments, a sensing coil may be placed within the dressing in place of or in addition to the CCD / RGB sensor. The coil may be coaxially mounted nested or offset within the dressing. In some embodiments, a separate probe may be used to house the coil, which may be held on the tissue and transmit the signal via a wired or wireless connection.

[0281] As described above, optical sensors can be used to measure wound appearance using an RGB sensor with an illumination source. The RGB sensor and illumination source can be pressed against the skin so that the light will penetrate into the tissue and take on the spectral characteristics of the tissue itself. Light propagation in tissue can be dominated by two main phenomena, scattering and attenuation. For attenuation, as light passes through tissue, its intensity is lost due to absorption by various components of the tissue. Blue light tends to be severely attenuated, while light at the red end of the spectrum tends to be least attenuated.

[0282] The scattering process is more complex and has various "forms" that must be considered. The first aspect of scattering is based on the size of the scattering center compared to the wavelength of the incident light. If the scattering center is much smaller than the wavelength of the light, Rayleigh scattering can be assumed. If the scattering center is around the wavelength of the light, the more detailed Mie scattering formula must be considered. Another factor involved in the scattered light is the distance between the input and output of the scattering medium. If the mean free path of the light (the distance between scattering events) is much greater than the distance traveled, ballistic photon transport is assumed. In the case of tissue, the scattering events are approximately 100 microns apart, so a path distance of 1mm will effectively randomize the photon direction and the system will enter the diffuse region.

[0283] Ultra-bright light emitting diodes (LEDs), RGB sensors, and polyester optical filters can be used as components of optical sensors to measure tissue color differentiation. For example, since surface color can be measured from reflected light, color can be measured from light that first passes through the tissue for a given geometry. This can include color sensing of diffusely scattered light from an LED in contact with the skin. In some embodiments, an LED can be used with a nearby RGB sensor to detect light that has diffused through the tissue. The optical sensor can be imaged with diffuse internal light or surface reflected light. The optical sensor can also be used to measure autofluorescence. Autofluorescence is used because the tissue absorbs light of one wavelength and emits light of another wavelength. In addition, dead tissue may not autofluoresce, and therefore this may be a very strong indication of whether the tissue is healthy. Due to the blue light (or even UV light) with such a short penetration depth, for example, UV light with a red light sensitive photodiode (or some other wavelength offset band) nearby may be very useful as a binary test for healthy tissue, which will autofluoresce at a very specific wavelength.

[0284] return Fig. 9 In an embodiment of the present invention, a dressing 1002 with a sensor 1004 can be positioned over a wound 1006. Similar to the previous Figure 1 , Figure 5A -B and Figure 7 In the system depicted in FIG. 1006 , the dressing can be connected to a negative pressure source that is configured to deliver negative pressure to a wound 1006. The sensor 1004 can communicate 1012 with a controller 1014 by any suitable wired or wireless means. In some embodiments, the communication from the sensor to the controller can be one-way, where the controller only receives information from the sensor. However, alternatively, the communication 1012 between the sensor and the controller can be two-way, where the sensor sends information to the controller, but also receives instructions and / or information from the controller. The controller 1014 can then communicate with the negative pressure source 1010 by wired or wireless means.

[0285] The controller can be any processing device capable of executing software. For example, the processing device can be a processor, a PC, a tablet, a smartphone, or other computer capable of running host software. In an embodiment, the controller can be attached to the dressing and / or the pump, or can be separate. When the system 1000 is running, the sensor 1004 collects video data from the wound 1006 over time. This video data can be collected and stored to be transmitted to the controller 1014 at periodic intervals, and / or the video data can be continuously transmitted to the controller. The wound video data collected by the sensor 1004 may have any data that may be collected from any sensor disclosed in this part or other parts of the specification, but is appropriately visible light data or IR data. In an embodiment, the sensor 1004 can detect the edge of the wound 1006 and then collect a video of the wound edge, for example, collecting optical data including motion and color information. Such information can then be transmitted to the controller 1014, whereby the controller applies EVM to the video. As previously described, EVM can be used to detect extremely subtle changes in individual positions / pixels within the video. In some embodiments, EVM can be applied to a single pixel. Such a single pixel may be from a single sensor, or combined / averaged from multiple sensors. In some embodiments, multiple pixels may be drawn from a single sensor or from multiple sensors, for example in an array. For motion detection (i.e., identifying tissue motion due to blood pulsating within the tissue, as described elsewhere), multiple closely aligned pixels may be required. However, in embodiments, a single pixel or multiple pixels of a single sensor may be used.

[0286] The change of color and / or motion can indicate the blood flow to the tissue around the wound or the wound itself. As will be described in more detail below, the change of color, motion or another parameter can indicate that the vacuum at the wound site should be increased, decreased or remain unchanged. If it should be increased or decreased, the controller can communicate 1016 with the negative pressure source 1010 and guide the negative pressure source 1010 to increase the vacuum or reduce the vacuum. Such communication can be in the form of a feedback loop, allowing the negative pressure source to continue to increase or decrease the vacuum at the wound site until the desired level, for example, the desired treatment parameters, is reached. In an embodiment, depending on the desired wound treatment, the negative pressure source can be configured to deliver continuous negative pressure or intermittent negative pressure.

[0287] In some embodiments, a time series analysis algorithm, such as an autoregressive integrated moving average (ARIMA), generalized autoregressive conditional heteroskedasticity (GARCH), or a cumulative sum (or cumulative total) can be used to determine changes in values ​​between pixel locations in a video frame over time, such as described in this section or elsewhere in this specification. For example, indicating blood flow or motion. The cumulative sum can be defined as a running sum of the differences between each sample and the mean (e.g., in the absence of change, the cumulative sum is zero). The cumulative sum can be used to track changes in underlying variables, including one or more of red, red delta, motion, or a calculated processing parameter. The values ​​of one or more cumulative sums determined can be compared to one or more thresholds to determine blood flow and / or motion and / or any suitable values ​​disclosed in this section or elsewhere in this specification.

[0288] In certain embodiments, the NPWT pump may use a proportional-integral-derivative (PID) type loop to ensure that the integrated blood flow is appropriate to maintain the tissue in an acceptable state, and an optimal pressure may be used to ensure optimal blood flow without excessive blood flow. PID type loops are well known in the art and are used to adjust the output of a pump as a process variable changes.

[0289] Advantageously, the use of an EVM enables the negative pressure source to respond to changes in the wound and surrounding tissue, rather than simply responding to the negative pressure level detected in the wound bed, as is known in the art. In addition, NPWT using an EVM can be tailored to the desired outcome (increased blood flow) rather than a nominal vacuum, potentially minimizing power consumption, pain, and vacuum injury while producing the correct effect. Such a reactive system can also have a proactive role in avoiding local ischemia because low blood flow can be detected and treated early before traditional detection. In an embodiment, the vacuum can be increased to provide increased blood flow and then maintained at this level when the increased vacuum begins to restrict flow. In addition, the system 1000 can treat edema by triggering an increase in NPWT when an area of ​​edema is identified, thereby minimizing edema by increasing the effective compression. In some embodiments, the maximum value of the color change may be undesirable because a high value may indicate that large blood vessels are close to the surface and are stretched.

[0290] Fig. 10A An embodiment of a method of EVM processing in conjunction with NPWT 1100 is depicted, which is effective for acquiring video data from the above Fig. 9 The steps for performing NPWT changes shown in the Figure 2 provide more details. Fig. 10A Reference is made to "modules", but those skilled in the art will understand that such modules may be software steps that can be completed on one or more computing devices, such as the above-mentioned Figure 8Such a computing device may be any computing device disclosed in this section or elsewhere in the specification, for example, a controller, a smartphone, a server, or a general computer, such as a laptop or desktop computer. In a first step, a video capture device 1102, such as a camera or other sensor device, such as disclosed in this section or elsewhere in the specification, captures a video of the wound to be treated with NPWT. In the case of NPWT applied via a wound dressing, the video may be acquired from a sensor in the dressing, below the dressing, above the dressing, or at any suitable location.

[0291] Next, video clips of a desired length 1104 (e.g., 10 seconds) are collected and stored 1104. Those skilled in the art will appreciate that video clips may have any suitable length, for example, about: 1 second, 5 seconds, 10 seconds, 15 seconds, 30 seconds, 60 seconds, 5 minutes, 1 hour, 12 hours, 24 hours, or more than 24 hours. Furthermore, in some embodiments, the video is continuously transmitted and continuously processed for analysis. The analysis may be performed on the video clips or the continuously transmitted video. Fig. 9 In some embodiments, the video may include at least about: 5 frames / second, 10 frames / second, 20 frames / second, 30 frames / second, 45 frames / second, 60 frames / second, 75 frames / second, 90 frames / second, 120 frames / second, or greater than 120 frames / second.

[0292] After capturing the video, the value of each position / pixel within the video is amplified via EVM1106. Such an EVM algorithm can be executed in any suitable software medium, such as MATLAB code. In embodiments involving videos captured with a standard camera in the visible spectrum, the EVM algorithm can be used to amplify the color values ​​of the image. For example, the EVM algorithm can amplify the red color value within the video. As described above, red can be an indication of blood perfusion to a particular tissue. Once the video clip or continuously streaming video has been processed, "processing parameters" are determined. For example, if the change in red is of interest, the change in red or the red increment can be determined for each position and / or pixel of interest and used to calculate the processing parameters. In some embodiments, the processing parameters can be calculated by the following steps 1110. First, one or more regions of interest are set within the video frame by selecting one or more pixels within a specific region of the video frame. In some embodiments, this can be set by the user by selecting all pixels around a specific baseline color range and / or a specific location on the tissue. In an embodiment, the region can use all sensors and / or collected pixels.

[0293] Next, the pixels within the region are averaged to provide an average value for each region per frame. The averaging process may incorporate refinement to eliminate outliers that may be introduced into the system. Then, as additional data is collected with each successive frame of the video, an array of averages over time may be generated. From these successive frames, the highest and lowest values ​​may be collected, for example, the highest red value and the lowest red value. Then, an average peak value may be calculated for the highest values, and an average valley value may be calculated from the lowest values. Subtracting this highest average peak value from the lowest average valley value yields a single value. This value may then be calibrated 1112 to equal a single parameter number, which is referred to as a "treatment parameter." As will be described below, the "treatment parameter" may be compared to a value in a lookup table 1116 to indicate whether the NPWT device should increase or decrease the application of negative pressure. If the treatment parameter is determined from the change in red color within the video, a higher treatment parameter will tend to indicate good blood perfusion, while a lower treatment parameter will tend to indicate poor blood flow.

[0294] like Fig. 10B As depicted, in certain embodiments, it may be implemented by the controller to reduce the use of high-speed sampling, and multiple frames may be combined to provide a signal at a lower frame rate. For example, at 1202, the values ​​of frames 1 and 2 may be combined, along with the values ​​of frames 3 and 4, and so on. The combination of 1+2 may then be compared to the values ​​of 3+4 to identify the highest and lowest signals used in calculating processing parameters. In some embodiments, the combined values ​​may be calculated 1204 in different ways, for example, by combining frames 2 and 3 to compare with the combination of frames 4 and 5, etc. Once the values ​​within each frame are combined, the magnitude of the change in the value may then be calculated in a manner similar to that described above by subtracting the average valley from the average peak. Processing parameters may be calculated from changes in the red value in a video that has been subjected to EVM. However, in other embodiments, any specific color value, such as blue or green, may be used. In addition, any specific value may be used that may be derived from a video generated by any sensor (such as spO2 or infrared) disclosed in this section or other parts of the specification.

[0295] return Fig. 10AOnce the treatment parameter has been calculated, the controller may compare the treatment parameter 1114 to a preset desired value or range. Such a desired value or range may be pre-set by the controller or by a clinician. Such a desired value or range may be determined from the literature, by experimentation, by an algorithm, or by other suitable means. In any case, using a desired value or range allows the controller to compare the calculated treatment parameter with the desired value or range in order to direct the NPWT device to apply more or less negative pressure. In an embodiment, if the treatment parameter is below the desired value or range, the controller may send a signal to the NPWT device to increase the amount of negative pressure at the wound. Conversely, if the treatment parameter is above the desired value or range, the controller may send a signal to the NPWT device to reduce the amount of negative pressure at the wound. If the calculated treatment parameter is already at the desired value or within the desired range, the controller may not send a signal to the NPWT device or send a signal to remain stable. In some embodiments, if the treatment parameter remains at an undesired value or range for a period of time, a warning may be generated.

[0296] In certain embodiments, the response to treatment parameter measurements may be self-optimizing, such that the software may explore the best response to each change in a treatment parameter by examining the treatment / response curve. For example, if a particular change in NPWT causes a significant shift in a treatment parameter, the system may adjust to change NPWT only by the desired amount. For example, NPWT may be adjusted until a maximum difference in EVM output is achieved. In certain embodiments, it may be advantageous to accumulate delays between treatment adjustments to allow the body time to respond to a previous change in treatment.

[0297] In some embodiments, if the treatment parameter is above or at a desired value, the controller may reduce the vacuum set point to a nominal value of -45 mmHg (+ / - 5 mmHg), unless the treatment parameter is also reduced to an undesired level that may increase the vacuum. In the case of a "low" differential (i.e., poor blood flow), the vacuum may be increased until the treatment parameter reaches the desired value or -125 mmHg (whichever is reached first). If the treatment parameter is too high, the vacuum may be reduced to, for example, (or -45 mmHg min), however, if the treatment parameter is too low (i.e., poor blood flow), the vacuum may be moved to a higher level, increasing to a -150 mmHg limit. In certain embodiments, the vacuum limits may be adjusted for specific physiological conditions. In embodiments, the lower limit of the vacuum may be set around approximately the following values: -600 mmHg, -500 mmHg, -400 mmHg, -300 mmHg, -250 mmHg, 200 mmHg, 175 mmHg, or approximately -235 mmHg.

[0298] In certain embodiments, possibly customized for a particular pump, once the process parameters 1114 are calculated, the parameters may be compared to values ​​stored in a "lookup table" 1116 within one or more computing devices (controllers). Fig.11A is a table of lookup values ​​for use with the Pico Pump System, as described earlier in this manual. Figures 5A-6B 1 and 2 are described. The first column represents various settings associated with set points for target negative pressure or vacuum. In certain embodiments, if the calculated treatment parameter is below a threshold or desired value or range, the setting within the lookup table may be increased by +1, thereby causing the controller to increase the vacuum to a vacuum range determined by the next setting. Conversely, if the treatment parameter is below the desired value or range, the setting may be decreased by 1, thereby causing the controller to direct the NPWT device to decrease the setting to the next lower parameter setting. This process may continue indefinitely in a loop until setting 1 or setting 7 is reached. In embodiments, this process may also occur if increasing the vacuum would decrease the treatment parameter.

[0299] In an embodiment, if the device is already at parameter setting 7, and the processing parameter is still below range, the NPWT device will remain at setting 7. Conversely, if the NPWT device is already at parameter setting 1, and the processing parameter is above the desired range or parameter, the NPWT device will remain at setting 1. In certain embodiments, when the lookup table setting is increased, if the processing parameter is decreased, the setting may revert to the previous setting. Fig. 11B Provides the RENASYS described above TM An embodiment of a lookup table for a pump. The process for adjusting the vacuum based on process parameters and comparing to the lookup table can be similar to Fig.11A The process is essentially the same.

[0300] In some embodiments, the lookup table settings may instead be equations, so the set values ​​may no longer be limited to integer values, but may also be X values ​​and nominal set points on the Y-axis [and pressure set points]. The parameter (X) value will then be set by the PI, PD or PID loop to match the optimal red increment value. The acceptable red increment value may be slightly modified (by the clinician) to take into account patients who are susceptible to pain, where beneficial but suboptimal therapy is preferred for pain. Continuous high red values ​​(with minimal red increment) will also be an indicator of bleeding, which is one of the highest risks of NPWT. Such control systems may also be suitable for pain management and bleeding identification systems integrated into software packages (such as the software system associated with Renasys described above). For example, although a specific bleeding location may be detected as pulsating, once the blood flow leaves the rupture, it no longer has pulsation, so the color can be identified as red, and the pulse rate is unchanged. Therefore, such an indication can be identified as bleeding and marked as a reason for immediate intervention, thereby triggering the shutdown of NPWT to minimize bleeding before the intervention is achieved.

[0301] In some embodiments, the computing system described herein may include one or more computing devices, such as servers, laptops, mobile devices (e.g., smartphones, smart watches, tablet computers, personal digital assistants), kiosks, car consoles, or, for example, media players. In an embodiment, the computing device may include one or more central processing units (CPUs), each of which may include a conventional or proprietary microprocessor. The computing device may also include one or more memories, such as a random access memory (RAM) for temporary storage of information, one or more read-only memories (ROM) for permanent storage of information, and one or more mass storage devices, such as a hard drive, a floppy disk, a solid-state drive, or an optical media storage device. In certain embodiments, a processing device, a cloud server, a server, or a gateway device may be implemented as a computing system. In one embodiment, the modules of the computing system are connected to a computer using a standard-based bus system. In various embodiments, the standard-based bus system may be implemented in, for example, a peripheral component interconnect (PCI), a microchannel, a small computer computing system interface (SCSI), an industrial standard architecture (ISA), and an extended ISA (EISA) architecture. In addition, the functions provided in the components and modules of the computing device disclosed herein may be combined into fewer components and modules, or further separated into additional components and modules.

[0302] The computing devices disclosed herein may be controlled and coordinated by operating system software, such as iOS, Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10, Windows Server, Embedded Windows, Unix, Linux, Ubuntu Linux, SunOS, Solaris, Blackberry OS, Android, or other operating systems. In Macintosh systems, the operating system may be any available operating system, such as MAC OS X. In other embodiments, the computing device 13000 may be controlled by a proprietary operating system. Conventional operating systems control and schedule computer processes for execution, perform memory management, provide file systems, networking, I / O services, and provide user interfaces, such as graphical user interfaces (GUIs), among others.

[0303] The computing device disclosed herein may include one or more I / O interfaces and devices, such as a touchpad or touch screen, but may also include a keyboard, a mouse, and a printer. In one embodiment, the I / O interfaces and devices 13110 include one or more display devices (e.g., a touch screen or a monitor) that allow data to be visually presented to a user. More specifically, the display device may provide, for example, a presentation of a GUI, application software data, and a multimedia presentation. The computing system disclosed herein may also include one or more multimedia devices, such as a camera, a speaker, a video card, a graphics accelerator, and a microphone.

[0304] In general, the term "module" as used herein refers to logic implemented in hardware or firmware, or to a set of software instructions written in a programming language (e.g., Python, Java, Lua, C, and / or C++), which may have entry points and exit points. A software module may be compiled and linked into an executable program, installed in a dynamic link library, or may be written in an interpreted programming language (e.g., BASIC, Perl, or Python). It should be understood that a software module may be called from other modules or from itself, and / or may be called in response to a detected event or interrupt. A software module configured to be executed on a computing device may be provided on a computer-readable medium, such as an optical disk, a digital video disk, a flash drive, or any other tangible medium. Such software code may be stored in part or in whole on a memory device that executes a computing device to be executed by the computing device. Software instructions may be embedded in firmware, such as an EPROM. It should also be understood that a hardware module may be composed of connected logic units (e.g., gates and triggers), and / or may be composed of programmable units (e.g., programmable gate arrays or processors). The block diagrams disclosed herein may be implemented as modules. The modules described herein may be implemented as software modules, but may be represented in hardware or firmware. Generally, the modules described herein refer to logical modules that may be combined with other modules or divided into sub-modules, regardless of their physical organization or storage.

[0305] Each process, method, and algorithm described in the preceding sections may be embodied in a code module and fully or partially automated by a code module that is executed by one or more computer systems or computer processors including computer hardware. The code module may be stored on any type of non-transitory computer-readable medium or computer storage device, such as a hard drive, solid-state memory|optical disk, and the like. The system and module may also be transmitted on various computer-readable transmission media (including wireless-based and wired / cable-based media) as a generated data signal (e.g., as part of a carrier or other analog or digital propagation signal), and may take various forms (e.g., as part of a single or multiplexed analog signal, or as multiple discrete digital packets or frames). The process and algorithm may be partially or completely implemented in a dedicated circuit. The results of the disclosed process and process steps may be stored in any type of non-transitory computer memory, such as volatile or non-volatile memory, either persistently or otherwise.

[0306] All features disclosed in this specification (including any accompanying presentation, claims, abstract and drawings), and / or all steps of any method or process so disclosed, etc. may be combined in any combination, except for at least some mutually exclusive combinations of such features and / or steps. The present disclosure is not limited to the details of any foregoing embodiments. The present disclosure extends to any one of the features disclosed in this specification (including any accompanying claims, abstract and drawings) or any novel combination of such features, or any one of the steps of any method or process so disclosed or any novel combination of such steps.

[0307] Various modifications to the embodiments described in this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not intended to be limited to those embodiments shown herein, but rather to the widest scope consistent with the principles and features disclosed herein. Certain embodiments of the disclosure are encompassed in the claims set listed below or presented in the future.

Claims

1. A wound treatment system, comprising: a negative pressure source configured to be in fluid communication with a wound dressing placed over the wound, the negative pressure source configured to provide negative pressure under the wound dressing; a visualization sensor located above the wound, the visualization sensor being configured to collect video data of the wound; as well as a controller in communication with both the negative pressure source and the visualization sensor, the controller being configured to: The video data is amplified by Euler video upscaling, wherein the Euler video upscaling comprises the following steps: decomposing the video data into different spatial frequency bands; applying the same temporal filter to all spatial frequency bands to produce filtered spatial bands; upscaling the filtered spatial band by a factor to produce an upscaling filtered spatial band; and adding the upscaled filtered spatial band to the video data and compressing to generate output video data; determining a treatment parameter from the output video data, wherein the treatment parameter is based on changes in color and / or motion indicative of blood flow to tissue surrounding a wound, or indicative of blood flow in a wound; and If the processing parameter is different from the threshold, causing the negative pressure source to increase or decrease the level of negative pressure provided, Wherein the processing parameters are determined by differences between region values ​​measured in the output video data.

2. A wound treatment system according to claim 1, wherein the video data includes RGB color data.

3. A wound treatment system according to any of the preceding claims, wherein the visualization sensor is configured to wirelessly communicate with the controller.

4. A wound treatment system according to any of the preceding claims, wherein the controller is configured to wirelessly communicate with the negative pressure source.

5. A wound treatment system according to any of the preceding claims, wherein the controller is configured to transmit a signal to the negative pressure source to increase the negative pressure if the treatment parameter is below a desired value.

6. A wound treatment system according to any of the preceding claims, wherein the controller is configured to cause the negative pressure source to reduce the level of negative pressure provided if the treatment parameter is above the threshold.

7. A wound treatment system according to any of the preceding claims, wherein the controller is configured to compare the treatment parameters to a plurality of threshold values.

8. A wound treatment system according to claim 7, wherein the controller is configured to perform the comparison using a lookup table.

9. A wound treatment system according to any of the preceding claims, wherein the treatment parameter is indicative of blood flow in the wound.

10. A wound treatment system according to any of the preceding claims, wherein the threshold corresponds to a desired blood flow level in the wound.

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