Biocompatible encapsulation and component stress relief for negative pressure wound therapy dressing implementing sensors
阅读说明：本技术 用于实施传感器的负压伤口治疗敷料的生物相容性封装和部件应力消除 (Biocompatible encapsulation and component stress relief for negative pressure wound therapy dressing implementing sensors ) 是由 艾伦·肯尼士·弗雷泽·格鲁根·亨特 李·帕廷顿 费利克斯·克拉伦斯·昆塔纳 丹尼尔·李·斯图尔 于 2018-07-23 设计创作，主要内容包括：本发明公开了用于用生物相容性涂层包封伤口敷料的一部分的装置和方法。在一些实施例中,方法包括用疏水涂层涂覆伤口敷料的柔性伤口接触层的第一侧。伤口接触层的第一侧可以支承多个电子部件。该方法还可包括用疏水涂层涂覆与第一侧相对的伤口接触层的第二侧。伤口接触层可以至少部分地由亲水性材料形成。(Devices and methods for encapsulating a portion of a wound dressing with a biocompatible coating are disclosed. In some embodiments, the method comprises coating a first side of a flexible wound contact layer of a wound dressing with a hydrophobic coating. The first side of the wound contact layer may support a plurality of electronic components. The method may further comprise coating a second side of the wound contact layer opposite the first side with a hydrophobic coating. The wound contact layer may be formed at least in part from a hydrophilic material.)
1. A method for coating a wound dressing, the method comprising:
coating a first side of a flexible wound contact layer of the wound dressing with a hydrophobic coating, the first side of the wound contact layer supporting a plurality of electronic components; and
coating a second side of the wound contact layer opposite the first side with the hydrophobic coating, the wound contact layer being formed at least in part from a hydrophilic material.
2. The method of any one of the preceding claims, further comprising encapsulating the wound contact layer with the coating.
3. The method of any preceding claim, wherein the coating is hydrophobic.
4. The method of any one of the preceding claims, wherein the coating is biocompatible.
5. The method of any preceding claim, wherein the coating is substantially stretchable.
6. The method of any preceding claim, wherein the plurality of electronic components comprises at least one electronic connection.
7. The method of any of the preceding claims, further comprising coating at least some of the plurality of electronic components with a multi-layer coating.
8. The method of any one of the preceding claims, wherein coating the first and second sides of the wound contact layer comprises spraying the coating.
9. The method of claim 8, wherein spraying comprises spraying with compressed air or an inert gas.
10. The method of any preceding claim, wherein the coating is formed from a material that complies with IEC60601 standard.
11. A method for coating a wound dressing, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible wound contact layer of the wound dressing with a first biocompatible coating; and
coating one or more remaining areas of a first side of the wound contact layer and a second side of the wound contact layer opposite the first side with a second biocompatible coating.
12. The method of claim 11, wherein the first coating is substantially non-stretchable.
13. The method of claim 11, wherein the first coating comprises at least one of Dymax 20351, Dymax 20558, Dymax9001-E, or Loctite 3211.
14. The method of any one of claims 11-13, wherein the wound contact layer is formed at least in part from a hydrophilic material.
15. The method of any one of claims 11-14, wherein the first coating and the second coating are hydrophobic.
16. The method of any one of claims 11 to 15, wherein the first and second coatings are formed from a material that complies with the IEC60601 standard.
17. The method of any one of claims 11-16, wherein the first coating has a viscosity of no more than about 50,000 centipoise.
18. A method for coating a wound dressing, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible wound contact layer of the wound dressing with a non-biocompatible coating; and
coating a first side of the wound contact layer comprising the plurality of electronic components and a second side of the wound contact layer opposite the first side with a biocompatible coating.
19. The method of claim 18, wherein the non-biocompatible coating is substantially non-stretchable.
20. The method of any one of claims 18-19, wherein coating a first side of the wound contact layer with the biocompatible coating comprises coating the non-biocompatible coating covering the plurality of electronic components.
21. The method of any one of claims 18-20, wherein the biocompatible coating is hydrophobic.
22. The method of any one of claims 18-21, wherein the biocompatible coating is formed from a material that complies with the IEC60601 standard.
23. A method of coating a wound dressing, the method comprising:
positioning a flexible wound contact layer of the wound dressing substantially in tension between a first frame and a second frame, the wound contact layer comprising a first side supporting a plurality of electronic components and a second side opposite the first side, the plurality of electronic components protruding from a surface of the first side, the second side being substantially smooth; and
coating the wound contact layer with a biocompatible coating.
24. The method of claim 23, further comprising:
supporting a first side of the wound contact layer in a substantially flat position with a mold comprising a plurality of recesses configured to support the plurality of electronic components; and
applying the coating substantially uniformly to the second side of the wound contact layer.
25. The method of claim 24, further comprising:
supporting a second side of the wound contact layer in a substantially flat position between the first and second frames; and
applying the coating substantially uniformly to the first side of the wound contact layer.
26. The method of any one of claims 23-25, wherein applying comprises spraying the biocompatible coating.
27. The method of claim 26, wherein spraying comprises spraying with compressed air or an inert gas.
28. The method of any one of claims 23-27, wherein coating comprises encapsulating the wound contact layer with the biocompatible coating.
29. The method of any one of claims 23-28, wherein the biocompatible coating is formed from a material that complies with the IEC60601 standard.
30. A method according to any of the preceding claims, further comprising making at least one perforation in the substantially flexible wound contact layer prior to coating the first side of the substantially flexible wound contact layer supporting the plurality of electronic components.
31. The method of claim 30, further comprising fabricating the at least one perforation beneath at least one electronic component.
32. The method of any one of claim 30 or claim 31, further comprising applying a higher pressure to the first side of the substantially flexible wound contact layer than to the second side when coating the first side.
33. A wound dressing prepared by a process comprising:
placing a plurality of electronic components on a first side of a wound contact layer of the wound dressing, the wound contact layer being formed at least in part from a hydrophilic material;
coating a first side of the wound contact layer comprising the plurality of electronic components with a hydrophobic coating; and
coating a second side of the wound contact layer opposite the first side with the hydrophobic coating.
34. The wound dressing of claim 33, wherein the wound contact layer is flexible.
35. The wound dressing of any one of claims 33-34, wherein the coating is biocompatible.
36. The wound dressing of any one of claims 33-35, wherein the coating is substantially stretchable.
37. The wound dressing of any one of claims 33-36, wherein the coating is formed from a material that complies with IEC60601 standards.
38. The wound dressing of any one of claims 33-37, wherein the process further comprises coating the plurality of electronic components with another substantially non-stretchable coating prior to coating the first side of the wound contact layer with the hydrophobic coating.
39. The wound dressing of any one of claims 33 to 38, wherein the process further comprises making at least one perforation in the wound contact layer prior to coating the first side of the wound contact layer supporting the plurality of electronic components.
40. The wound dressing of claim 39, wherein the at least one perforation is fabricated below at least one electronic component.
41. The wound dressing of any one of claims 39 or 40, wherein the process further comprises applying a higher pressure to the first side of the wound contact layer than to the second side when coating the first side.
42. A wound dressing made and/or coated by the method of any one of the preceding claims.
43. An apparatus for applying a wound dressing, the apparatus comprising:
a first frame;
a second frame configured to be attached to the first frame and further configured to secure a flexible wound contact layer of the wound dressing between the first frame and the second frame, the wound contact layer including a first side supporting a plurality of electronic components and a second side opposite the first side, the plurality of electronic components protruding from a surface of the first side, the second side being substantially smooth,
wherein the first frame and the second frame are configured to support the wound contact layer in substantial tension such that a biocompatible coating can be applied to the first side and the second side of the wound contact layer.
44. The apparatus of claim 43, further comprising a base and a mold, the mold comprising a plurality of grooves configured to support the plurality of electronic components, the mold and the first frame configured to be positioned on the base, the mold further configured to support a first side of the wound contact layer in a substantially flat position to allow the coating to be substantially uniformly applied to a second side of the wound contact layer.
45. The apparatus of claim 44, wherein the mold is configured to support a plurality of wound contact layers in the substantially flat position, at least a first wound contact layer of the plurality of wound contact layers comprising a different arrangement of electronic components than a second wound contact layer of the plurality of wound contact layers.
46. The device of any one of claims 43-45, wherein the wound contact layer comprises thermoplastic polyurethane.
47. The device of any one of claims 43 to 46, wherein the coating comprises a urethane acrylate.
48. The device of any one of claims 43-47, wherein the coating is applied to encapsulate the wound contact layer.
49. The apparatus of any one of claims 43 to 48, wherein at least one of the plate or the mold comprises nylon or Polytetrafluoroethylene (PTFE).
50. The device of any one of claims 43 to 49, wherein the coating is applied as a spray coating.
51. The device of claim 50, further comprising a spray device comprising a reservoir filled with compressed air or an inert gas and configured to dispense an uncured coating onto the wound contact layer such that oxygen is removed and the coating is allowed to cure.
52. The apparatus of any one of claims 43-51, wherein the wound contact layer is configured to provide negative pressure wound therapy.
53. An apparatus for applying a wound dressing, the apparatus comprising:
a body comprising a plurality of recesses configured to support a plurality of electronic components supported on a first side of a wound contact layer of the wound dressing, the plurality of electronic components protruding from a surface of the first side, the wound contact layer further comprising a second substantially smooth side opposite the first side,
wherein the body is configured to support a first side of the wound contact layer in a substantially flat position such that a biocompatible coating can be applied to a second side of the wound contact layer.
54. The apparatus of claim 53, wherein the plurality of recesses are shaped and positioned and shaped to substantially match a shape and positioning of the plurality of electronic components.
55. A method for coating an electronic device, the method comprising:
coating a first side of a flexible substrate of the electronic device with a hydrophobic coating, the first side of the substrate supporting a plurality of electronic components; and
coating a second side of the substrate opposite the first side with the hydrophobic coating, the substrate being at least partially formed of a hydrophilic material.
56. A method for coating an electronic device, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible substrate of the electronic device with a first biocompatible coating; and
coating one or more remaining areas of a first side of the substrate and a second side of the substrate opposite the first side with a second biocompatible coating.
57. A method for coating an electronic device, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible substrate of the electronic device with a non-biocompatible coating; and
coating a first side of the substrate including the plurality of electronic components and a second side of the substrate opposite the first side with a biocompatible coating.
58. A method of coating an electronic device, the method comprising:
positioning a flexible substrate of the electronic device substantially in tension between a first frame and a second frame, the substrate including a first side supporting a plurality of electronic components and a second side opposite the first side, the plurality of electronic components protruding from a surface of the first side, the second side being substantially smooth; and
coating the substrate with a biocompatible coating.
59. A wound dressing made and/or coated as shown and/or described.
60. A method of manufacturing and/or coating a wound dressing as shown and/or described.
61. An apparatus for applying a wound dressing as shown and/or described.
Technical Field
Embodiments of the present disclosure relate to devices, systems, and methods for treating tissue through monitoring of delivery sensors in communication with various treatment regions.
Background
Almost all medical fields can benefit from improved information about the state of the tissue, organ or system to be treated, especially if such information is collected in real time during the treatment, many types of treatment still being performed routinely without the use of sensor data acquisition. Rather, such processing relies on visual inspection by the caregiver or other limited means rather than quantitative sensor data. For example, in the case of wound treatment by dressing and/or negative pressure wound therapy, data acquisition is typically limited to visual inspection by the caregiver, and often the underlying wounded tissue may be obscured by bandages or other visual barriers. Even intact skin may have underlying lesions that are not visible to the naked eye, such as damaged blood vessels or deeper tissue damage that may lead to ulceration. Similar to wound management, during orthopedic procedures, it is necessary to immobilize the limb using a mold or other packaging, with only limited information being collected on the underlying tissue. In the case of internal tissue (e.g., bone plate) repair, continuous direct sensor-driven data acquisition is not performed. Furthermore, braces and/or sleeves for supporting musculoskeletal function do not monitor the function of the underlying muscles or movement of the limb. In addition to direct treatment, common hospital room items, such as beds and blankets, may be improved by increasing the ability to monitor patient parameters.
Accordingly, there is a need for improved sensor monitoring, particularly through the use of substrates implementing sensors that can be incorporated into existing processing schemes.
Disclosure of Invention
According to some embodiments, there is provided a method for coating a wound dressing, the method comprising:
coating a first side of a flexible wound contact layer of the wound dressing with a hydrophobic coating, the first side of the wound contact layer supporting a plurality of electronic components; and
coating a second side of the wound contact layer opposite the first side with the hydrophobic coating, the wound contact layer being formed at least in part from a hydrophilic material.
The method for coating a wound dressing described in any of the preceding paragraphs may further comprise one or more of the following features. The method may comprise encapsulating the wound contact layer with the coating. The coating may be hydrophobic, biocompatible, and/or substantially stretchable. The plurality of electronic components may include at least one electronic connection. The method may further include coating at least some of the plurality of electronic components with a multi-layer coating. Coating the first and second sides of the wound contact layer may comprise spraying the coating. Spraying includes spraying with compressed air or inert gas. The coating may be formed of a material that complies with the IEC60601 standard.
According to some embodiments, there is provided a method for coating a wound dressing, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible wound contact layer of the wound dressing with a first biocompatible coating; and
coating one or more remaining areas of a first side of the wound contact layer and a second side of the wound contact layer opposite the first side with a second biocompatible coating.
In some embodiments, the method of any of the preceding paragraphs may include one or more of the following features. The first coating may be substantially non-stretchable. The first coating can include at least one of Dymax 20351, Dymax 20558, Dymax9001-E, or Loctite 3211. The wound contact layer may be formed at least in part from a hydrophilic material. The first coating and the second coating may be hydrophobic and/or formed of a material that complies with IEC60601 standard. The first coating may have a viscosity of no more than about 50,000 centipoise.
According to some embodiments, there is provided a method for coating a wound dressing, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible wound contact layer of the wound dressing with a non-biocompatible coating; and
coating a first side of the wound contact layer comprising the plurality of electronic components and a second side of the wound contact layer opposite the first side with a biocompatible coating.
The method of any of the preceding paragraphs may include one or more of the following features. The non-biocompatible coating may be substantially non-stretchable. In some embodiments, coating the first side of the wound contact layer with the biocompatible coating comprises coating a non-biocompatible coating covering the plurality of electronic components. The biocompatible coating may be hydrophobic and/or formed of a material that complies with the IEC60601 standard.
According to some embodiments, there is provided a method for coating a wound dressing, the method comprising:
positioning a flexible wound contact layer of the wound dressing substantially in tension between a first frame and a second frame, the wound contact layer comprising a first side supporting a plurality of electronic components and a second side opposite the first side, the plurality of electronic components protruding from a surface of the first side, the second side being substantially smooth; and
coating the wound contact layer with a biocompatible coating.
The method of any of the preceding paragraphs may include one or more of the following features. The method may further include supporting the first side of the wound contact layer in a substantially flat position with a mold comprising a plurality of recesses configured to support the plurality of electronic components; and applying the coating substantially uniformly to the second side of the wound contact layer. The method may further include supporting a second side of the wound contact layer in a substantially flat position between the first frame and a second frame; and applying the coating substantially uniformly to the first side of the wound contact layer. In some embodiments, coating may comprise spraying the biocompatible coating and/or encapsulating the wound contact layer with the biocompatible coating. Spraying may include spraying with compressed air or an inert gas. The biocompatible coating is formed of a material that complies with the IEC60601 standard. In some embodiments, the method may further include making at least one perforation in the substantially flexible wound contact layer prior to coating the first side of the substantially flexible wound contact layer supporting the plurality of electronic components. The method may further comprise fabricating the at least one perforation beneath at least one electronic component. The method may further include applying a higher pressure to the first side of the substantially flexible wound contact layer than to the second side when coating the first side.
According to some embodiments, there is provided a wound dressing prepared by a process comprising:
placing a plurality of electronic components on a first side of a wound contact layer of the wound dressing, the wound contact layer being formed at least in part from a hydrophilic material;
coating a first side of the wound contact layer comprising the plurality of electronic components with a hydrophobic coating; and
coating a second side of the wound contact layer opposite the first side with the hydrophobic coating.
The wound dressing of any of the preceding paragraphs may include one or more of the following features. The wound contact layer may be flexible. The coating may be biocompatible, substantially stretchable and/or formed of a material in accordance with IEC60601 standards. The process may further include coating the plurality of electronic components with another substantially non-stretchable coating prior to coating the first side of the wound contact layer with the hydrophobic coating. The process may also include making at least one perforation in the wound contact layer prior to coating the first side of the wound contact layer supporting the plurality of electronic components. The at least one through-hole may be made below the at least one electronic component. The process may further include applying a higher pressure to the first side of the wound contact layer than to the second side when coating the first side.
According to some embodiments, there is provided a wound dressing manufactured and/or coated by any of the methods described herein.
According to some embodiments, there is provided an apparatus for applying a wound dressing, the apparatus comprising:
a first frame;
a second frame configured to be attached to the first frame and further configured to secure a flexible wound contact layer of the wound dressing between the first frame and the second frame, the wound contact layer including a first side supporting a plurality of electronic components and a second side opposite the first side, the plurality of electronic components protruding from a surface of the first side, the second side being substantially smooth,
wherein the first frame and the second frame are configured to support the wound contact layer in substantial tension such that a biocompatible coating can be applied to the first side and the second side of the wound contact layer.
The apparatus of any of the preceding paragraphs may include one or more of the following features. The apparatus may further include a base and a mold including a plurality of recesses configured to support the plurality of electronic components, the mold and the first frame configured to be positioned on the base, the mold further configured to support the first side of the wound contact layer in a substantially flat position to allow the coating to be substantially uniformly applied to the second side of the wound contact layer. The mold may be configured to support a plurality of wound contact layers in the substantially flat position, at least a first wound contact layer of the plurality of wound contact layers comprising a different arrangement of electronic components than a second wound contact layer of the plurality of wound contact layers. The wound contact layer may comprise a thermoplastic polyurethane. The coating may comprise a polyurethane acrylate and/or may be applied to encapsulate the wound contact layer. At least one of the plate or the mold may comprise nylon or Polytetrafluoroethylene (PTFE). In some embodiments, the coating may be applied as a spray coating. The device may further comprise a spray device comprising a reservoir filled with compressed air or an inert gas and configured to dispense an uncured coating onto the wound contact layer such that oxygen is removed and the coating is allowed to cure. The wound contact layer may be configured to provide negative pressure wound therapy.
According to some embodiments, there is provided an apparatus for applying a wound dressing, the apparatus comprising:
a body comprising a plurality of recesses configured to support a plurality of electronic components supported on a first side of a wound contact layer of the wound dressing, the plurality of electronic components protruding from a surface of the first side, the wound contact layer further comprising a second substantially smooth side opposite the first side,
wherein the body is configured to support a first side of the wound contact layer in a substantially flat position such that a biocompatible coating can be applied to a second side of the wound contact layer.
The apparatus of any of the preceding paragraphs may include one or more of the following features. The plurality of recesses may be shaped and positioned and shaped to substantially match the shape and positioning of the plurality of electronic components.
According to some embodiments, there is provided a method for coating an electronic device, the method comprising:
coating a first side of a flexible substrate of the electronic device with a hydrophobic coating, the first side of the substrate supporting a plurality of electronic components; and
coating a second side of the substrate opposite the first side with the hydrophobic coating, the substrate being at least partially formed of a hydrophilic material.
According to some embodiments, there is provided a method for coating an electronic device, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible substrate of the electronic device with a first biocompatible coating; and
coating one or more remaining areas of a first side of the substrate and a second side of the substrate opposite the first side with a second biocompatible coating.
According to some embodiments, there is provided a method for coating an electronic device, the method comprising:
coating a plurality of electronic components supported by a first side of a flexible substrate of the electronic device with a non-biocompatible coating; and
coating a first side of the substrate including the plurality of electronic components and a second side of the substrate opposite the first side with a biocompatible coating.
According to some embodiments, there is provided a method for coating an electronic device, the method comprising:
positioning a flexible substrate of the electronic device substantially in tension between a first frame and a second frame, the substrate including a first side supporting a plurality of electronic components and a second side opposite the first side, the plurality of electronic components protruding from a surface of the first side, the second side being substantially smooth; and
coating the substrate with a biocompatible coating.
Other embodiments of wound dressings, devices, kits, and related methods are described below.
Drawings
Embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which:
fig. 1A illustrates a negative pressure wound treatment system according to some embodiments;
fig. 1B illustrates a wound dressing according to some embodiments;
FIG. 2 illustrates a sensor array showing sensor placement incorporated into a wound dressing, according to some embodiments;
FIG. 3A illustrates a flexible sensor array including a sensor array portion, a tail portion, and connector pad end portions, according to some embodiments;
FIG. 3B illustrates a flexible circuit board with different sensor array geometries according to some embodiments;
FIG. 3C illustrates a sensor array portion of the sensor array shown in FIG. 3B;
fig. 3D illustrates a flexible sensor array incorporated into a perforated wound contact layer, in accordance with some embodiments;
FIG. 3E illustrates a control module according to some embodiments;
4A-4C illustrate a wound dressing having a plurality of electronic components according to some embodiments;
5A-5B illustrate a coating of a wound dressing according to some embodiments;
fig. 6 illustrates coating a wound dressing with two biocompatible coatings according to some embodiments;
fig. 7 illustrates coating a wound dressing with a biocompatible coating according to some embodiments;
fig. 8 illustrates an apparatus for applying a wound dressing according to some embodiments;
fig. 9 illustrates spraying a wound dressing according to some embodiments;
fig. 10 illustrates a mold for coating a wound dressing according to some embodiments;
fig. 11 illustrates another apparatus for applying a wound dressing according to some embodiments;
12A-12B illustrate an assembled apparatus for applying a wound dressing according to some embodiments;
fig. 13 illustrates a release liner for coating a wound dressing according to some embodiments;
14A-14B illustrate applying a wound dressing according to some embodiments;
fig. 15 illustrates spray coating a wound dressing according to some embodiments;
FIG. 16 illustrates applying a non-stretchable material to a wound dressing according to some embodiments;
17A-17B illustrate a comparison of performance with and without stretchable material according to some embodiments;
fig. 18 illustrates a wound dressing with one or more perforations according to some embodiments; and
fig. 19A-B illustrate coating a wound dressing with one or more perforations according to some embodiments.
Detailed Description
Embodiments disclosed herein relate to apparatuses and methods for monitoring and treating biological tissue with a substrate implementing a sensor. The embodiments disclosed herein are not limited to treating or monitoring a particular type of tissue or wound, and indeed, the techniques of implementing sensors disclosed herein are broadly applicable to any type of treatment that may benefit from a substrate on which the sensors are implemented. Some embodiments utilize healthcare provider dependent sensors and data acquisition to make diagnoses and patient management decisions.
Some embodiments disclosed herein relate to the use of sensors mounted on or embedded within a substrate configured for treatment of intact and damaged human or animal tissue. Such sensors may collect information about surrounding tissue and transmit such information to a computing device or caregiver for further processing. In some embodiments, these sensors may be attached to the skin anywhere on the body, including areas that are monitored for arthritis, temperature, or other areas that may be prone to problems and require monitoring. The sensors disclosed herein may also incorporate markers, such as radiopaque markers, to indicate the presence of the device, for example, prior to performing MRI or other techniques.
The sensor embodiments disclosed herein may be used in conjunction with apparel. Non-limiting examples of apparel for use with embodiments of the sensors disclosed herein include shirts, pants, trousers, skirts, undergarments, gowns, 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 a particular garment. The sensor embodiments may be printed directly onto the garment and/or embedded into the fabric. Breathable and printable materials, such as microporous films, may also be suitable.
The sensor embodiments disclosed herein may be incorporated into cushions or mattresses, for example, within a hospital bed, to monitor patient characteristics, such as any of the characteristics disclosed herein. In certain embodiments, disposable membranes containing such sensors may be placed on hospital beds and removed/replaced as needed.
In some implementations, the sensor embodiments disclosed herein can 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.
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 with stents, sleeves, packaging materials, supports, and other suitable articles. 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 characteristics such as acceleration, which may be used for concussion diagnostics.
The sensor embodiments disclosed herein may be used with a surgical device (e.g., the NAVIO surgical system of Smith & Nephew, inc.). In embodiments, sensor embodiments disclosed herein may communicate with such surgical devices to guide the placement of the surgical devices. In some embodiments, sensor embodiments disclosed herein can monitor blood flow to or from a potential surgical site or ensure that blood flow is not present at the surgical site. Additional surgical data may be acquired to help prevent scarring and to monitor areas away from the affected area.
To further assist in surgical techniques, the sensors disclosed herein may be incorporated into surgical drapes to provide information about the tissue under the drape that may not be immediately visible to the naked eye. For example, a sensor-embedded flexible drape may have sensors that are advantageously positioned to provide improved area-centric data acquisition. In certain embodiments, the sensor embodiments disclosed herein may be incorporated into the boundary or interior of a drape to create a fence to confine/control an operating room.
Sensor embodiments as disclosed herein may also be used for pre-operative evaluation. For example, such sensor embodiments may be used to gather information about potential surgical sites, for example, by monitoring the skin and underlying tissue for possible incision sites. For example, the perfusion level or other suitable characteristic may be monitored deeper into the skin surface and tissue to assess whether an individual patient is likely to be at risk for surgical complications. Sensor embodiments, such as those disclosed herein, can be used to assess the presence of a microbial infection and provide an indication of the use of an antimicrobial agent. 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.
The 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 communicate such information to another device and/or caregiver. For example, such devices may monitor pulse rate, blood oxygen, and/or electrical activity of the heart. Similarly, the sensor embodiments disclosed herein may be used in neurophysiological applications, such as monitoring electrical activity of neurons.
The sensor embodiments disclosed herein may be incorporated into implantable devices, such as implantable orthopedic implants, including flexible implants. Such sensor embodiments may be configured to gather information about the implant site and transmit that information to an external source. In some embodiments, an internal source may also provide power to this implant.
The sensor embodiments disclosed herein may also be used to monitor biochemical activity on or below the surface of the skin, such as lactose accumulation in muscle or sweat production on the surface of the skin. In some embodiments, other characteristics may 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 dehiscence.
The sensor embodiments disclosed herein may be incorporated into an ear-nose-throat (ENT) application. For example, such sensor embodiments may be used to monitor recovery from ENT-related procedures, such as wound monitoring within the sinus tract.
As described in more detail below, the sensor embodiments disclosed herein may encompass sensor printing techniques with encapsulation, such as encapsulation with a polymer film. Such films may be constructed using any of the polymers described herein, such as polyurethane. The packaging of the sensor embodiments may provide water resistance of the electronics and protection of local tissue, local fluids, and other potential sources of damage.
In certain embodiments, the sensors disclosed herein may be incorporated into an organ protection layer, as disclosed below. The sensor-embedded organ protection layer can protect the organ of interest and confirm that the organ protection layer is in place and provide protection. Furthermore, the organ protection layer of the embedded sensor may 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 organ protection layer implementing the sensor may be used to monitor the transplanted organ, for example, by monitoring the fat and muscle content of the organ. Furthermore, the organ may be monitored during and after transplantation (e.g., during recovery of the organ) using the organ protection layer implementing the sensor.
The sensor embodiments disclosed herein may be incorporated into a 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 condition that may benefit from improved monitoring of the implemented sensors.
Wound treatment
Some embodiments disclosed herein relate to wound therapy for the human or animal body. Thus, any reference herein to a wound may refer to a wound on a human or animal body, and any reference herein to a body may refer to a human or animal body. Embodiments of the disclosed technology may relate to preventing or minimizing damage to physiological or living tissue, or to treating wounds of damaged tissue (e.g., a wound as described herein) with or without reduced pressure, including, for example, negative pressure sources and wound dressing components and devices. Devices and components comprising the wound covering and filler material or inner layer (if present) are sometimes referred to herein collectively as dressings. In some embodiments, the wound dressing may be provided for use without reducing pressure.
Some embodiments disclosed herein relate to wound therapy for the human or animal body. Thus, any reference herein to a wound may refer to a wound on a human or animal body, and any reference herein to a body may refer to a 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., wounds as described herein).
As used herein, the expression "wound" may include damage to living tissue, typically skin that is incised or ruptured, that may be caused by cutting, pounding or other impact. The wound may be a chronic or acute injury. Acute wounds occur as a result of surgery or trauma. They undergo various stages of healing over the expected time frame. Chronic wounds usually begin with acute wounds. When an acute wound does not follow the healing phase, the acute wound may become a chronic wound, prolonging recovery time. The transition from acute to chronic wounds is thought to be due to immune impairment of the patient.
Chronic wounds may include, for example: venous ulcers (such as those occurring in the legs), which occupy most chronic wounds and affect mainly the elderly; diabetic ulcers (e.g., foot or ankle ulcers); peripheral arterial disease; pressure sores or Epidermolysis Bullosa (EB).
Examples of other wounds include, but are not limited to, abdominal wounds or other large or incisional wounds that result from either surgery, trauma, sternotomy, fasciotomy, or other conditions, dehiscent wounds, acute wounds, chronic wounds, subacute and dehiscent wounds, traumatic wounds, flap and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure sores, stomas, surgical wounds, traumatic ulcers, venous ulcers, and the like.
Wounds may also include deep tissue damage. Deep tissue injury is a term proposed by the national pressure sore counseling group (NPUAP) to describe a unique form of pressure sore. Clinical physicians have for many years described these ulcers in terms such as purple pressure sores, ulcers that may worsen and bruise on bony elevations.
Wounds may also include tissue at risk of becoming a wound as discussed herein. For example, the tissue at risk may include tissue on bony prominences (with risk of deep tissue damage/injury) or pre-operative tissue (e.g., knee tissue) that may be cut (e.g., for joint replacement/surgical alteration/reconstruction).
Some embodiments relate to methods of treating wounds using the techniques disclosed herein in combination with one or more of the following: advanced footwear, turning the patient, debriding (e.g., debriding a diabetic foot ulcer), treatment of infection, systemic fusion, antimicrobial, antibiotic, surgery, removing tissue, affecting blood flow, physiological therapy, exercise, bathing, nutrition, hydration, nerve stimulation, ultrasound, electrical stimulation, oxygen therapy, microwave therapy, active agent ozone, antibiotic, antimicrobial, and the like.
Alternatively or additionally, the wound may be treated with topical negative pressure and/or traditional advanced wound care, which is not assisted by the use of applied negative pressure (also referred to as non-negative pressure therapy).
Advanced wound care may include the use of absorbent dressings, occlusive dressings, the use of antimicrobial and/or debriding agents (e.g., cushioning or compression therapy such as stockings or bandages) in wound dressings or appendages, pads, and the like.
In some embodiments, these wounds may be treated using traditional wound care, where a dressing may be applied to the wound to facilitate and promote wound healing.
Some embodiments relate to a method of manufacturing a wound dressing, comprising providing a wound dressing as disclosed herein.
Wound dressings that can be used in conjunction with the disclosed techniques include any known in the art. The technique is applicable to negative pressure therapy treatment as well as non-negative pressure therapy treatment.
In some embodiments, the wound dressing includes one or more absorbent layers. The absorbent layer may be a foam or a superabsorbent.
In some embodiments, the wound dressing may include a dressing layer comprising a polysaccharide or modified polysaccharide, polyvinylpyrrolidone, 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 as being useful for forming wound dressing layers for negative pressure therapy or non-negative pressure therapy.
In some embodiments, the polymeric substrate may be a polysaccharide or a modified polysaccharide.
In some embodiments, the polymeric substrate may be cellulose. The cellulosic material may comprise a hydrophilically modified cellulose, such as methyl cellulose, carboxymethyl cellulose (CMC), carboxymethyl cellulose (CEC), ethyl cellulose, propyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, carboxyethyl cellulose sulfate, alkyl cellulose sulfonate, or mixtures thereof.
In certain embodiments, the cellulosic material may be a cellulose alkyl sulfonate. The alkyl moiety of the alkylsulfonate substituent may be an alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, or butyl. The alkyl moiety may be branched or unbranched and thus a suitable propyl sulphonate substituent may be 1-or 2-methyl-ethyl sulphonate. The butylsulfonate substituent may be 2-ethyl-ethanesulfonate, 2, 2-dimethyl-ethanesulfonate or 1, 2-dimethyl-ethanesulfonate. The alkyl sulfonate substituent may be 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.
The cellulose alkyl sulfonate may have varying degrees of substitution, chain length of the cellulose backbone structure, and structure of the alkyl sulfonate substituent. Solubility and absorption depend mainly on the degree of substitution: as the degree of substitution increases, the cellulose alkyl sulfonate becomes more and more soluble. It follows that as the solubility increases, the absorption increases.
In some embodiments, the wound dressing further comprises a top layer or cover layer.
The thickness of the wound dressing disclosed herein may be between 1mm and 20mm, or between 2mm and 10mm, or between 3mm and 7 mm.
In some embodiments, the disclosed techniques may be used in conjunction with non-negative pressure dressings. A non-negative pressure wound dressing suitable for providing protection at a wound site may comprise:
an absorbent layer for absorbing wound exudate and
a masking element for at least partially masking the view of wound exudate absorbed by the absorbent layer in use.
The shading element may be partially translucent.
The masking element may be a masking layer.
The non-negative pressure wound dressing may also include an area in or near the masking element to allow viewing of the absorbent layer. For example, the shading element layer may be disposed over a central region of the absorbing layer and not over a border region of the absorbing layer. In some embodiments, the masking element is or is coated with a hydrophilic material.
The shading elements may comprise a three-dimensional knitted spacer fabric. Spacer fabrics are known in the art and may include a knitted spacer fabric layer.
The shading element may also include an indicator to indicate that the dressing needs to be changed.
In some embodiments, the shield element is provided as a layer at least partially above the absorbent layer, in use being further away from the wound site than the absorbent layer.
The non-negative pressure wound dressing may also include a plurality of openings in the shield member to allow fluid to move therethrough. The masking element may comprise or be coated with a material having size exclusion properties for selectively allowing or preventing passage of molecules of a predetermined size or weight.
The shading elements may be configured to at least partially mask optical radiation having wavelengths of 600nm and less.
The shading elements may be configured to reduce light absorption by 50% or more.
The shading elements may be configured to produce CIE L values of 50 or more, and optionally 70 or more. In some embodiments, the shading elements may be configured to produce CIE L values of 70 or greater.
In some embodiments, the non-negative pressure wound dressing may further comprise at least one of a wound contact layer, a foam layer, an odor control element, a pressure resistant layer, and a cover layer.
In some embodiments, a cover layer is present, and the cover layer is a translucent film. Typically, the translucent film has a moisture vapor transmission rate of 500g/m2/24 hours or greater.
The translucent film may be a bacterial barrier.
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 the wound site.
A non-negative pressure wound dressing as disclosed herein may include a masking element and an absorbent layer provided as a single layer.
In some embodiments, the non-negative pressure wound dressings disclosed herein include a foam layer, and the material of the shielding element includes a component that may be displaced or damaged by movement of the shielding element.
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 present, the odor control element can be dispersed within or adjacent to the absorbent layer or the masking element. Alternatively, when present, the odour control element may be provided as a layer sandwiched between the foam layer and the absorbent layer.
In some embodiments, the disclosed techniques for non-negative pressure wound dressings include a method of manufacturing a wound dressing comprising: providing an absorbent layer for absorbing wound exudate; and providing a masking element for at least partially masking the view of wound exudate absorbed by the absorbent layer in use.
In some embodiments, a non-negative pressure wound dressing may be adapted to provide protection at a wound site, including: an absorbent layer for absorbing wound exudate; and a barrier layer disposed over the absorbent layer and further from the wound-facing side of the wound dressing than the absorbent layer. The shielding layer may be disposed directly over the absorbing layer. In some embodiments, the shielding layer comprises a three-dimensional spacer fabric layer.
The barrier layer increases the area of pressure transmission applied to the dressing by 25% or more or the initial area of application. For example, the barrier 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.
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.
The non-negative pressure wound dressing as disclosed herein may further comprise a permeable cover layer for allowing gas and vapor transmission therethrough, the cover layer being disposed over the barrier layer, wherein the through-holes of the cover layer are offset from the through-holes of the barrier layer.
Non-negative pressure wound dressings may be suitable for treating pressure sores.
A more detailed description of the non-negative pressure dressing disclosed above is provided in WO2013007973, the entire content of which is hereby incorporated by reference.
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 the wound site; and a support layer configured to reduce shrinkage of at least a portion of the wound dressing.
In some embodiments, the multilayer wound dressings disclosed herein further comprise a liquid impermeable film layer, wherein the support layer is positioned between the absorbent layer and the film layer.
The support layer disclosed herein may comprise a mesh. The web may include a geometric structure having a plurality of generally geometric apertures extending therethrough. For example, the geometric structure may include a plurality of bosses substantially evenly spaced and joined by the polymeric strands to form generally geometric pores between the polymeric strands.
The mesh may be formed of high density polyethylene.
The apertures may have an area of 0.005mm2 to 0.32mm 2.
The support layer may have a tensile strength of 0.05Nm to 0.06 Nm.
The support layer may have a thickness of 50 μm to 150 μm.
In some embodiments, the support layer is located immediately adjacent 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 further comprise a tie layer, wherein the support layer is thermally laminated to the fibers in the absorbent layer through the tie layer. The tie layer may comprise a low melting point adhesive, such as an ethylene vinyl acetate adhesive.
In some embodiments, the multilayer wound dressings disclosed herein further comprise an adhesive layer attaching the film layer to the support layer.
In some embodiments, the multilayer wound dressings disclosed herein further comprise a wound contact layer positioned adjacent the absorbent layer for positioning adjacent a wound. The multilayer wound dressing may further comprise a fluid transport layer between the wound contact layer and the absorbent layer for transporting exudate away from the wound into the absorbent layer.
A more detailed description of the multi-layer wound dressing disclosed above is provided in uk patent application no GB1618298.2 filed on 28/10/2016, the entire contents of which are hereby incorporated by reference.
In some embodiments, the disclosed techniques may 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 comprised of at least one layer of nonwoven textile fibers folded into multifolds to form a pleated structure. In some embodiments, the wound dressing further comprises a second layer of material that is temporarily or permanently attached to the first layer of material.
Typically, the vertically overlapping material has been cut.
In some embodiments, the first layer has a pleating 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.
The first layer material may comprise one or more of fibres made from synthetic natural or inorganic polymers, natural fibres of cellulose, protein or mineral origin.
The wound dressing may include two or more absorbent layers of material stacked on top of another material, with the two or more layers having the same or different densities or compositions.
In some embodiments, the wound dressing may include only one layer of absorbent material of vertically overlapping material.
The layer of absorbent material is a blend of natural or synthetic, organic or inorganic fibers and binder fibers or bicomponent fibers, typically PET with a low melt temperature PET coating to soften at a specified temperature and act as a binder throughout the blend.
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 a derivative thereof.
In some embodiments, the wound dressings disclosed herein have a second layer comprising a foam or dressing fixture.
The foam may be a polyurethane foam. The polyurethane foam may have an open or closed cell structure.
The dressing fixture may include a bandage, tape, gauze, or backing layer.
In some embodiments, the wound dressings disclosed herein comprise a layer of absorbent material attached directly to a second layer by lamination or by an adhesive, and the second layer is attached to a dressing anchor layer. The adhesive may be an acrylic adhesive or a silicone adhesive.
In some embodiments, the wound dressings disclosed herein further comprise a layer of superabsorbent fibers, or a layer of viscose or polyester fibers.
In some embodiments, the wound dressing disclosed herein further comprises a backing layer. The backing layer may be a transparent or opaque film. Typically, the backing layer comprises a polyurethane film (typically a transparent polyurethane film).
A more detailed description of the multi-layer wound dressing disclosed above is provided in uk patent application No. GB1621057.7 filed on 12/2016 and uk patent application No. GB1709987.0 filed on 22/6/2017, the entire contents of which are hereby incorporated by reference.
In some embodiments, a non-negative pressure wound dressing may include an absorbent component for a wound dressing, the component including a 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.
The absorbent member may be in the form of a sheet.
The wound contact layer may comprise a woven or non-woven or knitted gel-forming fibrous layer.
The foam layer may be an open cell foam or a closed cell foam, typically an open cell foam. The foam layer is a hydrophilic foam.
The wound dressing may include features that form islands in direct contact with the wound that is surrounded by the perimeter of the adhesive attaching the dressing to the wound. The adhesive may be a silicone or acrylic adhesive, typically a silicone adhesive.
The wound dressing may be covered by a film layer on the surface of the dressing furthest from the wound.
A more detailed description of a wound dressing of this type is provided above in EP2498829, the entire content of which is hereby incorporated by reference.
In some embodiments, a non-negative pressure wound dressing may comprise a multi-layer wound dressing for a wound that produces high levels of exudate, wherein the dressing comprises: a transmission layer having an MVTR of at least 300gm2/24 hours; an absorbent core comprising gel-forming fibers capable of absorbing and retaining exudates; a wound contact layer comprising gel-forming fibres which transport exudate to an absorbent core; and a bonding layer positioned on the absorbent core, the absorbent core and wound contact layer limiting lateral diffusion of exudate from the dressing to the wound area.
The wound dressing is capable of handling at least 6g (or 8g and 15g) of fluid per 10cm2 of the dressing in 24 hours.
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 cellulosic fibres, typically sodium carboxymethylcellulose fibres.
The wound dressing may include a wound contact layer having a lateral wicking rate of 5 mm/min to 40 mm/min. The wound contact layer may have a fiber density of between 25gm2 and 55gm2, for example, 35gm 2.
The absorbent core may have an exudate absorbency of at least 10g/g and typically has a lateral wicking rate of less than 20mm per minute.
The absorbent core may have a blend in the range of up to 25 wt% of cellulosic fibers and 75 wt% to 100 wt% of gel-forming fibers.
Alternatively, the absorbent core may have a blend in the range of up to 50 wt% of cellulose fibers and from 50 to 100 wt% of gel-forming fibers. For example, the blend is in the range of 50 wt% cellulosic fibers and 50 wt% gel-forming fibers.
The density of the fibers in the absorbent core may be between 150gm2 and 250gm2, or about 200gm 2.
The shrinkage of the wound dressing when wetted may be less than 25% or less than 15% of its original size/dimension.
The wound dressing may include a transmission layer, and the layer is a foam. The transfer layer may be a polyurethane foam laminated to a polyurethane film.
The wound dressing may comprise one or more layers selected from the group comprising a dissolvable drug film layer, an odour absorbing layer, a diffusion layer and an additional adhesive layer.
The wound dressing may be 2mm and 4mm thick.
The wound dressing may be characterized by a bonding layer bonding the absorbent core to an adjacent layer. In some embodiments, the bonding layer may be positioned on the wound-facing side of the absorbent core or 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.
A more detailed description of a wound dressing of this type is provided above in EP1718257, the entire content of which is hereby incorporated by reference.
In some embodiments, the non-negative pressure wound dressing may be a compression bandage. Compression bandages are known for use in the treatment of, for example, edema of the lower extremities and other venous and lymphatic diseases.
Compression bandage systems typically employ multiple layers, including a backing layer between the skin and the compression layer or layers. Compression bandages may be used, for example, to treat wounds of venous leg ulcers.
In some embodiments, the compression bandage may include a bandage system including a skin-facing inner layer including a first foam layer and a second layer of an absorbent nonwoven web, and an elastic outer layer, the inner and outer layers being sufficiently elongated to be capable of being wrapped around a limb of a patient. Compression bandages of this type are disclosed in WO99/58090, the entire contents of which are hereby incorporated by reference.
In some embodiments, a compression bandage system comprises: a) an inner elongated skin-facing elastic bandage comprising: (i) an elongated elastomeric substrate, and
(ii) an elongate foam layer adhered to one face of the substrate and extending 33% or more across the face of the substrate in a transverse direction and 67% or more across the face of the substrate in a longitudinal direction; and b) an outer elongate 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 content of which is hereby incorporated by reference.
In some embodiments, other compression bandage systems, such as those disclosed in US 6,759,566 and US2002/0099318, the entire contents of which are hereby incorporated by reference.
Negative pressure wound dressing
In some embodiments, treatment of such wounds may be performed using negative pressure wound therapy, wherein reduced 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.
It should be understood that embodiments of the present disclosure are generally suitable for use in a topical negative pressure ("TNP") therapy system. Briefly, negative pressure wound therapy helps to close and heal "difficult to heal" wounds of various morphologies by reducing tissue edema, promoting blood flow and granulation tissue formation, removing excess exudate, and may reduce bacterial load (thereby reducing infection risk). In addition, the therapy allows the wound to be less disturbed, resulting in faster healing. TNP therapy systems may also assist in the healing of surgically closed wounds by removing fluid and by helping to stabilize the tissue in close proximity to the closure site. Additional beneficial uses of TNP therapy may be found in grafts and flaps where removal of excess fluid is important and where close proximity of the graft to the tissue is required to ensure tissue viability.
Negative pressure therapy may be used to treat open or chronic wounds that are too large to spontaneously close or otherwise heal by applying negative pressure to the wound site. Topical Negative Pressure (TNP) therapy or Negative Pressure Wound Therapy (NPWT) involves placing a cover over the wound that is impermeable or semi-permeable to fluids, sealing the cover to the patient tissue surrounding the wound using various means, and connecting a source of negative pressure (such as a vacuum pump) to the cover in a manner that causes negative pressure to be created and maintained under the cover. It is believed that this negative pressure promotes wound healing by promoting the formation of granulation tissue at the wound site and assisting the body's normal inflammatory process while removing excess fluid that may contain adverse cytokines or bacteria.
Some of the dressings used in NPWT may include many different types of materials and layers, for example, gauze, pads, foam pads, or multi-layer wound dressings. One example of a multilayer 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 can-less 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 may be used to pump fluid out of the dressing or to transfer negative pressure from the pump to the wound dressing. Additionally, RENASYS-F, RENASYS-G, RENASYS-AB and RENASYS-F/AB, available from Smith & Nephew, are additional examples of NPWT wound dressings and systems. Another example of a multilayer wound dressing is the ALLEVYN Life dressing available from Smith & Nephew, which includes a moist wound environment dressing for treating a wound without the use of negative pressure.
As used herein, a reduced or negative pressure level (e.g., -X mmHg) represents a pressure level relative to normal ambient atmospheric pressure, which may correspond to 760mmHg (or 1atm, 29.93inHg, 101.325kPa, 14.696psi, etc.). Therefore, the negative pressure value-X mmHg reflects an absolute pressure lower than 760mmHg by X mmHg, or in other words, reflects an absolute pressure (760-X) mmHg. Further, a negative pressure "lower" or "less" than X mmHg corresponds to a pressure closer to atmospheric pressure (e.g., -40mmHg is less than-60 mmHg). A negative pressure "higher" or "greater" than-X mmHg corresponds to a pressure further away from atmospheric pressure (e.g., -80mmHg is greater than-60 mmHg). In some embodiments, local ambient atmospheric pressure is used as a reference point, and such local atmospheric pressure may not necessarily be, for example, 760 mmHg.
The negative pressure range of some embodiments of the present disclosure may be about-80 mmHg, or between about-20 mmHg and-200 mmHg. It should be noted that these pressures are based on normal ambient atmospheric pressure (which may be 760 mmHg). Thus, in practice, -200mmHg would be about 560 mmHg. In some embodiments, the pressure range may be between about-40 mmHg and-150 mmHg. Alternatively, pressure ranges of up to-75 mmHg, up to-80 mmHg, or above-80 mmHg may be used. Additionally, in other embodiments, pressure ranges below-75 mmHg may be used. Alternatively, the negative pressure device may supply a pressure range in excess of about-100 mmHg, or even-150 mmHg.
In some embodiments of the wound closure devices described herein, increased wound contraction may result in increased tissue expansion in the surrounding wound tissue. This effect may be enhanced by varying the force applied to the tissue (e.g., by varying the negative pressure applied to the wound over time), possibly in combination with increased tension applied to the wound via various embodiments of the wound closure device. In some embodiments, for example, the negative pressure may be varied over time using a sine wave, a square wave, or synchronized with one or more patient physiological indicators (e.g., heart beat). Examples of such applications in which additional disclosure related to the foregoing may be found include U.S. patent No. 8,235,955 entitled "Wound treatment device and method" published on 8, 7, 2012; and U.S. patent No. 7,753,894 entitled "Wound cleansing apparatus with stress" published on 7/13/2010. The disclosures of both of these patents are hereby incorporated by reference in their entirety.
Embodiments of the wound dressings, wound dressing components, wound treatment apparatuses, and methods described herein may also be used in combination with or in addition to those described in the following documents: international application No. PCT/IB2013/001469 entitled "apparatus and method FOR NEGATIVE PRESSURE WOUND THERAPY (apparatus and method FOR NEGATIVE PRESSURE WOUND THERAPY)" filed on day 5, month 22, 2013 and published on day 11, month 28, 2013 and published as WO 2013/175306a 2; U.S. patent application No. 14/418,908 entitled "WOUND dressing and TREATMENT METHOD (WOUND DRESSING AND METHOD OF healing) filed on day 7, 9, 2015 at 1, 30, 2015 as published as US 2015/0190286a1, the disclosure OF which is hereby incorporated by reference in its entirety. Embodiments OF the WOUND dressing, WOUND dressing components, WOUND treatment apparatus and METHODs described herein may also be used in combination with or in addition to those described in U.S. patent application No. 13/092,042 entitled "WOUND dressing and METHOD OF USE" (WOUND DRESSING AND METHOD OF USE) filed on day 21/4/2011, and U.S. patent application No. 14/715,527 entitled "fluid CONNECTOR for negative PRESSURE WOUND THERAPY (fluent CONNECTOR for WOUND THERAPY) filed on 24/2016 a1 filed on 24/18/2016, the disclosure OF which is hereby incorporated herein by reference in its entirety, filed on 21/4/2011, including other details regarding WOUND dressings, WOUND dressing components and principles, and embodiments OF materials for WOUND dressings.
Furthermore, some embodiments relating to TNP wound treatment involving wound dressings that incorporate the pumps AND/or associated electronics described herein may also be used in combination with or in addition to those described in international application PCT/EP2016/059329 entitled "REDUCED PRESSURE APPARATUS AND METHODS" (REDUCED PRESSURE APPARATUS AND METHODS), filed on 26/4/2016, published as WO 2016/174048, 11/3/2016.
NPWT System overview
Fig. 1A illustrates one embodiment of a negative or reduced pressure wound therapy (or TNP)
The
Some embodiments of
The
Some embodiments of the system are designed to operate without the use of a bleed liquid tank. Some embodiments may be configured to support a bleed liquid tank. In some embodiments, configuring the
In some embodiments, the
In operation, wound
Wound Dressings that may be used with the pump assemblies 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 negative pressure wound therapy systems that may be used with pump assemblies and other embodiments of the present application may 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 may be used.
Overview of wound dressing
Fig. 1B illustrates a cross-section through a wound dressing 155 according to some embodiments. Fig. 1B also illustrates a fluid connector 160 according to some embodiments. Wound dressing 155 may be similar to the wound dressing described in international patent publication WO2013175306a2, which is incorporated herein by reference in its entirety. Alternatively, wound dressing 155 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 positioned over a wound site to be treated. Wound dressing 155 may be placed to form a sealed cavity over a wound, such as
An upper, top or upper layer as used herein refers to the layer that is furthest from the skin or surface of the wound when the dressing is in use and positioned over the wound. Thus, a lower surface, layer, sub-layer or layer refers to the layer closest to the skin or surface of the wound when the dressing is in use and positioned over the wound.
The wound contact layer 222 may be a polyurethane or polyethylene layer or other flexible layer that is perforated, such as by a hot-pin process, a laser ablation process, an ultrasonic process, or in some other manner, or otherwise made permeable to liquids and gases. Wound contact layer 222 has a lower surface 224 (e.g., facing the wound) and an upper surface 223 (e.g., facing away from the wound). Perforations 225 preferably include through-holes in wound contact layer 222 that allow fluid to flow through layer 222. Wound contact layer 222 helps prevent tissue ingrowth into the other materials of the wound dressing. In some embodiments, the perforations are small enough to meet this requirement while still allowing fluid to flow therethrough. For example, perforations formed as slits or holes having a size in the range of 0.025mm to 1.2mm are considered to be small enough to help prevent tissue ingrowth 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 155 while also creating an airtight seal around the absorbent pad to maintain negative pressure at the wound site. In some embodiments, the wound contact layer is configured to allow one-way or substantially one-way or one-way flow of fluid through the wound contact layer when negative pressure is applied to the wound. For example, the wound contact layer may allow fluid to flow through the wound contact layer away from the wound, but not allow fluid to flow back toward the wound. In some cases, the perforations in the wound contact layer are configured to allow such unidirectional or unidirectional fluid flow through the wound contact layer.
Some embodiments of wound contact layer 222 may also serve as a carrier for optional lower and upper adhesive layers (not shown). For example, the lower pressure sensitive adhesive may be provided on the lower surface 224 of the wound dressing 155 and the 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 alternatively on a selected one of the two sides of the wound contact layer, or not formed on both sides. The lower pressure sensitive adhesive layer, when used, can help adhere the wound dressing 155 to the skin surrounding the wound site. In some embodiments, the wound contact layer may comprise a perforated polyurethane film. The lower surface of the membrane 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.
A layer 226 of porous material may be positioned over the wound contact layer 222. This porous or transmission layer 226 allows the transmission of fluids including liquids and gases away from the wound site into the upper layers of the wound dressing. In particular, the transmission layer 226 may ensure that the open air channels maintain a negative pressure delivered over the wound area even when the absorbent layer absorbs large amounts of exudate. The layer 226 may remain open under typical pressures applied during negative pressure wound therapy as described above, such that an equalized negative pressure is seen across the wound site. 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 knit polyester) or a non-woven fabric may be used.
In some embodiments, the transmission layer 226 comprises a 3D polyester spacer fabric layer comprising a top layer (i.e. the layer distal to the wound bed in use) of 84/144 textured polyester, and a bottom layer (i.e. the layer proximal to the wound bed in use) of 10 denier flat polyester, and a third layer sandwiched between the two layers, the third layer being an area defined by knitted polyester viscose, cellulose or similar monofilament fibres. Of course, other materials and other linear mass densities of fibers may be used.
Although reference is made throughout this disclosure to monofilament fibers, it should be understood that multiple strand alternatives may of course be used. Thus, the top spacer fabric has a greater number of filaments in the yarns used to form it than the number of filaments that make up the yarns used to form the bottom spacer fabric layer.
This difference between the number of filaments in the spaced apart layers helps to control the flow of moisture through the transfer layer. In particular, by having a greater number of filaments in the top layer, i.e., the top layer is made of yarns having more filaments than the yarns used for the bottom layer, liquid tends to wick more along the top layer than the bottom layer. In use, this difference tends to wick liquid away from the wound bed and into the central region of the dressing where the absorbent layer 221 helps to lock the liquid out or wick the liquid forward on itself toward the liquid-transpirable cover layer.
In some embodiments, to improve the flow of liquid through the transmission layer 226 (that is, perpendicular to the channel region formed between the top and bottom spacer layers), the 3D fabric may be treated with a dry cleaning agent (e.g., without limitation, perchloroethylene) to help remove any manufactured products, such as previously used mineral oils, fats, or waxes, that may interfere with the hydrophilic ability of the transmission layer. Subsequently, an additional manufacturing step may be performed in which the 3D spacer fabric is washed in a hydrophilic agent (such as, but not limited to, Feran Ice 30g/l available from Rudolph Group). This process step helps to ensure that the surface tension on the material is very low so that liquids such as water can enter the 3D knitted fabric once they contact the fabric. This also helps to control the flow of the liquid fouling component of any exudate.
The absorbing material layer 221 may be disposed over the transmission layer 226. Absorbent materials, including foams or non-woven natural or synthetic materials, and optionally super-absorbent materials, form reservoirs for fluids (particularly liquids) removed from the wound site. In some embodiments, layer 221 may also help absorb fluids toward backing layer 220.
The material of the absorbent layer 221 may also prevent liquids collected in the wound dressing 155 from freely flowing within the dressing, and may serve to contain any liquids collected within the dressing. The absorbent layer 221 also helps distribute fluid throughout the layer via wicking for fluid absorption from the wound site and storage throughout the absorbent layer. This helps to prevent accumulation in the area of the absorbent layer. The capacity of the absorbent material must be sufficientTo manage the exudate flow rate of the wound when negative pressure is applied. Since, in use, the absorbent layer is subjected to a negative pressure, the material of the absorbent layer is selected to absorb liquid in this case. There are many materials, such as superabsorbent materials, that are capable of absorbing liquid under negative pressure. The absorption layer 221 may be generally composed of ALLEVYNTMFoam, Freudenberg 114-TM11C-450. In some embodiments, the absorbent layer 221 can include a composite including a superabsorbent powder, a fibrous material, such as cellulose, and a binding fiber. In some embodiments, the composite is an airlaid thermal bond composite.
In some embodiments, the absorbent layer 221 is a layer of nonwoven cellulosic fibers having superabsorbent material in the form of dry particles dispersed throughout. The use of cellulose fibers introduces a fast wicking element that helps to rapidly and uniformly distribute the liquid absorbed by the dressing. The juxtaposition of the multi-strand fibers results in a strong capillary action in the fiber mat, which helps to distribute the liquid. In this way, the superabsorbent material is effectively supplied with liquid. Wicking also helps to bring liquid into contact with the overlying layer to help increase the transpiration rate of the dressing.
An orifice, hole, or aperture 227 may be provided in the backing layer 220 to allow negative pressure to be applied to the dressing 155. In some embodiments, the fluid connector 160 is attached or sealed to the top of the backing layer 220 over the aperture 227 created in the dressing 155 and transmits negative pressure through the aperture 227. A length of tubing may be coupled at a first end to fluid connector 160 and at a second end to a pump unit (not shown) to allow fluid to be pumped out of the dressing. Where the fluid connector is adhered to the top layer of the wound dressing, a length of tubing may be coupled at the first end of the fluid connector such that the tubing or conduit extends parallel or substantially to the top surface of the dressing away from the fluid connector. The fluid connector 160 may be adhered and sealed to the backing layer 220 using an adhesive, such as acrylic, cyanoacrylate, epoxy, UV curable, or hot melt adhesive. The fluid connector 160 may be formed from a soft polymer, such as polyethylene, polyvinyl chloride, silicone, or polyurethane, having a shore a durometer of 30 to 90. In some embodiments, the fluid connector 160 may be made of a soft or conformable material.
In some embodiments, the absorbent layer 221 includes at least one through-hole 228 positioned so as to be located below the fluid connector 160. 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. As shown in fig. 1B, a single through-hole may be used to create an opening located below fluid connector 160. It will be appreciated that a plurality of openings may alternatively be used. Further, if more than one port is used according to certain embodiments of the present disclosure, one or more openings may be created in the absorbent layer and the obscuring layer in registration with each respective fluid connector. Although not necessary for certain embodiments of the present disclosure, the use of through-holes in the superabsorbent layer can provide fluid flow paths that remain unobstructed, particularly when the absorbent layer is near saturation.
As shown in fig. 1B, an aperture or via 228 may be provided in the absorber layer 221 below the aperture 227, such that the aperture is directly connected to the transmission layer 226. This allows the negative pressure applied to the fluid connector 160 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 it absorbs wound exudate. In other embodiments, no apertures may be provided in the absorbent layer 221, or a plurality of apertures located below the aperture 227 may be provided. In other alternative embodiments, additional layers (e.g., another transmission layer or a masking 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.
The backing layer 220 may be air impermeable, but permeable to water vapor, and may extend across the width of the wound dressing 155. The backing layer 220, which may be, for example, a polyurethane film (e.g., Elastollan SP9109) having a pressure sensitive adhesive on one side, is air impermeable, and this layer thus serves to cover the wound and seal the wound cavity on 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 chamber a negative pressure can be created. For example, the backing layer 220 may be sealed to the wound contact layer 222 in a border area around the circumference of the dressing by adhesive or welding techniques, ensuring that no air is drawn through the border area. The backing layer 220 protects the wound from external bacterial contamination (bacterial barrier) and allows liquid from wound exudate to be transported through this layer and evaporate from the outer surface of the film. The backing layer 220 may include two layers: a polyurethane film and an adhesive pattern coated on the film. The polyurethane film is permeable to moisture and may be made of a material that has an increased permeability to water when wetted. In some embodiments, the moisture permeability of the backing layer increases when the backing layer becomes wet. The moisture permeability of the wet back liner may be up to about ten times greater than the moisture permeability of the dry back liner.
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 facilitates a faster absorption of exudate to the absorbent layer. Furthermore, the further channels ensure that no liquid can collect around the perimeter of the wound cavity, which might otherwise penetrate through the seal around the perimeter of the dressing, resulting in the formation of leaks. As shown in fig. 1B, the absorbent layer 221 may define a perimeter that is smaller than 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.
As shown in fig. 1B, one embodiment of the wound dressing 155 includes an aperture 228 in the absorbent layer 221 below the fluid connector 160. In use, for example when negative pressure is applied to the dressing 155, the wound-facing portion of the fluid connector may thus be in contact with the transmission layer 226, which may thus facilitate transmission of 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 aperture 228 is at least 1-2mm larger than the diameter of the wound facing portion or aperture 227 of the fluid connector 11.
For example, in embodiments having a single fluid connector 160 and through-hole, it may be preferable for the fluid connector 160 and through-hole to be located in an off-center position. Such a position may allow the dressing 155 to be positioned on the patient such that the fluid connector 160 is elevated relative to the remainder of the dressing 155. So positioned, the fluid connector 160 and filter 214 are less likely to come into contact with wound fluid that may prematurely occlude the filter 214, such that transmission of negative pressure to the wound site is impaired.
Turning now to fluid connector 160, some embodiments include a sealing surface 216, a bridge 211 having a proximal end (closer to the negative pressure source) and a
Some embodiments may also include an optional second fluid passageway positioned above the first fluid passageway 212. For example, some embodiments may provide air leakage that may be disposed at a proximal end of a top layer configured to provide an air path into the first fluid pathway 212 and the dressing 155, similar to the suction adapter described in U.S. patent No. 8,801,685, which is incorporated herein by reference in its entirety.
In some embodiments, the fluid pathways 212 are constructed of a compliant material that is flexible and also allows fluid to pass therethrough if the spacers kink or fold. Suitable materials for the fluid pathway 212 include, without limitation, foams, including open foams, such as polyethylene or polyurethane foams, meshes, 3D knitted fabrics, nonwovens, and fluid channels. In some embodiments, the fluid passage 212 may be constructed 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 so that the fluid pathway 212 is still able to transport fluid from the wound toward the negative pressure source when kinked or bent.
In some embodiments, the fluid pathway 212 may be formed of a wicking fabric, such as a knitted or woven spacer fabric (e.g., knitted polyester 3D fabric, BaltexOr Gehring
In some embodiments, the filter element 214 is liquid impermeable, but gas permeable, and is provided to act as a liquid barrier and ensure that no liquid is able to escape from the wound dressing 155. The filter element 214 may also act as a bacterial barrier. Typically, the pore size is 0.2 μm. Suitable materials for the filter material of the filter element 214 include 0.2 micron Gore from the MMT seriesTMExpanded PTFE, PALL VersaporeTM200R and DonaldsonTMTX 6628. Larger pore sizes may also be used, but these may require a secondary filtration layer to ensure complete bioburden containment. Since the wound fluid contains liquid, it is preferred, but not necessary, to use an oleophobic filter membrane, e.g., 1.0 micron MMT-332, before 0.2 micron MMT-323. This prevents the lipid from clogging the hydrophobic filter. The filter element may be attached or sealed to the cover membrane over the port or aperture. For example, the filter element 214 may be molded into the fluid connector 160, or may be adhered to one or both of the top of the cover layer and the bottom of the suction adapter 160 using an adhesive (such as, but not limited to, a UV cured adhesive).
It should be understood that other types of materials may be used for the filter element 214. More generally, microporous films, which are thin flat sheets of polymeric material containing billions of micropores, can be used. Depending on the membrane selected, these pores may range in size from 0.01 to greater than 10 microns. Microporous membranes have both hydrophilic (drainage) and hydrophobic (waterproofing) forms. In some embodiments, the filter element 214 includes a support layer and an acrylic copolymer membrane sheet formed on the support layer. In some embodiments, wound dressing 155 according to certain embodiments uses a Microporous Hydrophobic Membrane (MHM). Many polymers can be used to form MHMs. For example, the MHM may be formed from one or more of PTFE, polypropylene, PVDF, and acrylic copolymers. All of these optional polymers may be treated to obtain specific surface characteristics that may be hydrophobic and oleophobic. Thus, these will reject liquids with low surface tension, such as multi-vitamin infusions, lipids, surfactants, oils and organic solvents.
The MHM blocks liquid while allowing air to flow through the membrane. They are also highly efficient air filters that eliminate potentially infectious aerosols or particles. It is well known that a single piece MHM is an alternative to mechanical valves or vents. Accordingly, configuring the MHM may reduce product assembly costs to improve patient profits and cost/benefit ratios.
The filter element 214 may also include an odor absorbing material such as activated carbon, carbon fiber cloth, or Vitech Carbotec-RT Q2003073 foam, among others. For example, the odor absorbing material may form a layer of the filter element 214, or may be sandwiched between microporous hydrophobic membranes of the filter element. The filter element 214 thus allows gas to vent through the pores. However, the dressing contains liquids, particles and pathogens.
Wound dressing 155 may include a spacer element 215 in combination with fluid connector 160 and filter 214. By adding this spacing element 215, the fluid connector 160 and filter 214 may be supported without direct contact with the absorbent layer 220 or transmission layer 226. The absorptive 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 fluid during use may therefore be minimized.
Similar to the embodiments of the wound dressings described above, some wound dressings include a perforated wound contact layer having a silicone adhesive on the skin-contacting side and an acrylic adhesive on the back side. A transmission layer or 3D spacer fabric mat is located above the boundary layer. The absorption layer is located above the transmission layer. The absorbent layer may comprise a super absorbent Nonwoven (NW) mat. The absorbent layer may be about 5mm across the transmission layer at the perimeter. The absorbent layer may have an aperture or through hole towards one end. The orifice may be about 10mm in diameter. The backing layer is positioned over 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 wound contact layer encapsulate the transmission layer and the absorbent layer, creating a peripheral boundary of about 20 mm. The backing layer may have a10 mm aperture overlying the aperture in the absorbent layer. A fluid connector may be attached over the well, the fluid connector including a liquid impermeable, gas permeable semi-permeable membrane (SPM) overlying the orifice.
Wound dressing with sensor
A wound dressing comprising a plurality of sensors may be utilized in order to monitor the characteristics of the wound as it heals. Collecting data from both well-healed and non-well-healed wounds may provide useful insight to identify the measured object to indicate whether the wound is on the healing track.
In some embodiments, a number of sensor technologies may be used for the wound dressing or one or more components forming part of the overall wound dressing apparatus. For example, as shown in fig. 2 and 3D, which describe wound
The sensor-integrated wound contact layer may be placed in contact with the wound and will allow fluid to pass through the contact layer while causing little or no damage to the tissue in the wound. The sensor-integrated wound contact layer may be made of a flexible material such as silicone and may contain antimicrobial agents or other therapeutic agents known in the art. In some embodiments, the sensor-integrated wound contact layer may comprise an adhesive that adheres to wet or dry tissue. In some embodiments, the sensor or sensor array may be incorporated into or encapsulated in other components of the wound dressing (e.g., the absorbent or spacer layer described above).
As shown in fig. 2 and 3D, five sensors may be used, including, for example, sensors for: temperature (e.g., 25 thermistor sensors in a5 x5 array, 20mm pitch), oxygen saturation or SpO2 (e.g., 4 or 5 SpO2 sensors in a single line from the center of the wound contact layer to its edge, 10mm pitch), tissue color (e.g., 10 optical sensors in a2 x5 array, 20mm pitch; not all 5 sensors in each row of the array need to be aligned), pH (e.g., by measuring the color of the pH sensitive pad, optionally using the same optical sensor as the tissue color), and conductivity (e.g., 9 conductive contacts in a 3 x3 array, 40mm pitch). As shown in fig. 3A, the SpO2 sensors may be arranged in a single column from the center or near the center of the wound contact layer to the edge of the wound contact layer. The SpO2 sensor column may allow the sensor to measure changes between regions in the middle of a wound, at the edge or wound, or on the intact skin. In some embodiments, the wound contact layer or sensor array may be larger than the size of the wound to cover the entire surface area of the wound as well as the surrounding intact skin. The larger size of the wound contact layer and/or sensor array and plurality of sensors may provide more information about the wound area than if the sensors were placed only in the center of the wound or only in one area at a time.
The sensor may be bonded to a flexible circuit board formed of flexible polymers including polyamides, Polyimides (PI), polyesters, polyethylene naphthalate (PEN), Polyetherimides (PEI), along with various Fluoropolymers (FEP) and copolymers, or any material known in the art. The sensor array may be incorporated into a two-layer flex circuit. In some embodiments, the circuit board may be a multilayer flexible printed circuit. In some embodiments, these flexible circuits may be incorporated into any layer of the wound dressing. In some embodiments, the flexible circuit may be incorporated into the wound contact layer. For example, the flexible circuit may be incorporated into a wound contact layer similar to that described with reference to fig. 1B. The wound contact layer may have cuts or slits that allow one or more sensors to protrude from the lower surface of the wound contact layer and directly contact the wound area.
In some embodiments, the sensor-integrated wound contact layer may include first and second wound contact layers with the flexible circuit board sandwiched between the two layers of wound contact layer material. The first wound contact layer has a lower surface intended to be in contact with a wound and an upper surface intended to be in contact with a flexible circuit board. The second wound contact layer has a lower surface intended to be in contact with the flexible circuit board and an upper surface intended to be in contact with the wound dressing or one or more components forming part of the overall wound dressing apparatus. The upper surface of the first wound contact layer and the lower surface of the second wound contact layer may be adhered together by a flexible circuit board sandwiched between the two layers.
In some embodiments, the one or more sensors of the flexible circuit board may be completely encapsulated or covered by the wound contact layer to prevent contact with moisture or fluids in the wound. In some embodiments, the first wound contact layer may have a cut or slit that allows the one or more sensors to protrude from the lower surface and directly contact the wound area. For example, one or more SpO2 sensors as shown in fig. 3D are shown protruding from the bottom surface of the wound contact layer. In some embodiments, the SpO2 sensor may be mounted directly on the lower surface of the first wound contact layer. Some or all of the sensors and electrical or electronic components may be potted or encapsulated (e.g., rendered waterproof or liquidproof) with a polymer (e.g., a silicon or epoxy-based polymer). Encapsulation with a polymer can prevent fluid ingress and leaching of chemicals from the component. In some embodiments, the wound contact layer material may seal the component to prevent water from entering and leaching out chemicals.
In some embodiments, collecting and processing information related to a wound may use three components, including a sensor array, a control or processing module, and software. These components are described in more detail herein.
Fig. 3A illustrates a flexible sensor
FIG. 3B illustrates an embodiment of a flexible circuit board having four different
FIG. 3C illustrates in more detail the
Fig. 3D illustrates a flexible sensor array incorporated into a perforated
The connections of the sensor array may vary depending on the various sensors and sensor array designs used. In some embodiments, for example, as shown in fig. 3B, a total of 79 connections may be used to connect the components of the sensor array. The sensor array may terminate in two parallel 40-way 0.5mm pitch Flat Flex Cable (FFC) contact surfaces with terminals on the top surface designed to connect to an FFC connector, such as Molex 54104-4031.
In some embodiments, one or more of a thermistor, conductivity sensor, SpO2 sensor, or color sensor may be used on the sensor array to provide information related to the status of the wound. The sensor array and individual sensors may assist the clinician in monitoring the healing of the wound. One or more sensors may operate individually or in coordination with one another to provide data relating to the wound and wound healing characteristics.
The temperature sensor may use a thermocouple or a thermistor to measure the temperature. The thermistor may be used to measure or track the temperature of the underlying wound or the thermal environment within the wound dressing. The thermometric sensors may be calibrated, and data obtained from the sensors may be processed to provide information about the wound environment. In some embodiments, an ambient sensor that measures the ambient air temperature may also be used to help eliminate problems associated with ambient temperature excursions.
Optical sensors can be used to measure wound appearance using RGB sensors with illumination sources. In some embodiments, both the RGB sensor and the illumination source may be pressed against the skin such that the light will penetrate into the tissue and present 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 may be 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 minimally attenuated.
The scattering process may be more complex and may have various "regions" (regions) that must be considered. A first aspect of scattering is based on a comparison of the size of the scattering center with the wavelength of the incident light. If the scattering center is much smaller than the wavelength of light, Rayleigh (Rayleigh) scattering can be assumed. If the scattering center is around the wavelength of light, then a more detailed Mie scattering formula must be considered. Another factor involved in scattering light is the distance between the input and output of the scattering medium. Ballistic photon transmission is assumed if the mean free path of light (the distance between scattering events) is much greater than the distance traveled. In the case of tissue, the scattering events are about 100 microns apart, so a path distance of 1mm will effectively randomize the photon direction and the system will enter the diffuse region.
Ultra bright Light Emitting Diodes (LEDs), RGB sensors and polyester optical filters can be used as components of optical sensors to measure by tissue color differentiation. For example, since the surface color can be measured from reflected light, the color can be measured from light that first passes through the tissue for a given geometry. This may include color sensing of diffusely scattered light from an LED in contact with the skin. In some embodiments, LEDs may be used with nearby RGB sensors to detect light that has diffused through tissue. The optical sensor may be imaged with diffuse internal light or surface reflected light.
In addition, optical sensors may be used to measure autofluorescence. Autofluorescence is used because tissue absorbs light at one wavelength and emits light at another wavelength. In addition, dead tissue may not auto-fluoresce, and thus this may be a very strong indication of whether the tissue is healthy or not. Because of the blue light (or even UV light) with such a short penetration depth, UV light with, for example, a red sensitive photodiode (or some other wavelength shift band) in the vicinity can be very useful as a binary test for healthy tissue, which will auto-fluoresce at very specific wavelengths.
Conductivity sensors can be used to determine the difference between live and dead tissue, or to indicate changes in impedance due to opening a wound in diseased tissue. The conductivity sensor may include an Ag/AgCl electrode and an impedance analyzer. The conductivity sensor may be used to measure impedance changes in the wound growth area by measuring the impedance of the surrounding tissue/area. In some embodiments, the sensor array may utilize conductivity sensors to measure changes in conductivity across the peripheral electrodes due to changes in wound size or wound shape. In some embodiments, the conductivity sensor may be used in the wound bed or on the wound periphery.
In some embodiments, a pH change pad may be used as a pH sensor. A spectrometer and a broadband white light source can be used to measure the spectral response of the pH dye. Illumination and imaging may be provided on the surface of the wound dressing in contact with the wound and on the same side as the fluid application (bottom surface). Alternatively, in some embodiments, the illumination and imaging sources may be disposed on the top surface of the dressing opposite the bottom surface and away from the surface to which the fluid is applied.
In some embodiments, a pulse oximetry SpO2 sensor may be used. To measure the degree of oxidation of blood, pulsatile blood flow was observed. Pulse oximetry works by time-resolved measurements of light absorption/transmission in tissue at two different wavelengths of light. When hemoglobin is oxidized, its absorption spectrum changes relative to non-oxygenated blood. By making measurements at two different wavelengths, a ratiometric measure of the degree of blood oxygenation can be obtained.
The components in the sensor array may be connected by a plurality of connections. In some embodiments, the thermistors may be arranged in groups of five. Each thermistor has a nominal value of 10k omega and each group of five has a common ground. There are five groups of thermistors, for a total of 30 connections. In some embodiments, there may be nine conductive terminals. One connection is required for each conductive terminal, providing a total of 9 connections. In some embodiments, there may be five SpO2 sensors. Each SpO2 sensor required three connections, plus power and ground (these were independently covered), for a total of 15 connections. In some embodiments, there may be 10 color sensors. Each color sensor includes an RGB LED and an RGB photodiode. Six connections are required for each color sensor, but five of them are common to each sensor, providing a total of 15 connections. Power and ground are considered separately. In some embodiments, there may be 5 pH sensors. The pH sensor may be a color changing disk and may be sensed using the color sensor described above. Therefore, no additional connections are required for the pH sensor. There may be three power rails and seven ground return signals, providing a total of 10 common connections. In some embodiments, the sensor array may include 25 thermistors (Murata NCP15WB473E03RC), 9 conductive terminals, 5 SpO2(ADPD144RI), 10 RGB LEDs (e.g., KPTF-1616RGBC-13), 10 RGB color sensors, 10 FETs, a Printed Circuit Board (PCB), and components.
The control module may be configured to interface with the sensor array. In some embodiments, the control module may contain a power source, such as a battery, and electronics for driving the sensors. The control module may also record data at appropriate intervals and allow the data to be transferred to an external computing device, such as a Personal Computer (PC). Depending on the sensors used in the sensor array and the data collected by the sensors, the control module may be customized to have various characteristics. In some embodiments, the control module may be comfortable enough and small enough to be worn for several weeks in succession. In some embodiments, the control module may be positioned adjacent to or on the wound dressing. In some embodiments, the control module may be located at a remote location from the wound dressing and accompanying sensor array. The control module may communicate with the sensor array and the wound dressing, whether located on, near, or remote from the wound dressing, via wires or via wireless communication. In some embodiments, the control module may be adapted for use with different sensor arrays, and may enable easy replacement of the sensor arrays.
In some embodiments, the control module may include various combinations of requirements and features including, but not limited to, the features listed in table 1 below.
TABLE 1 optional features of the control Module
FIG. 3E illustrates a block diagram 330 of a control module according to some embodiments. The block diagram of the control module includes a conductivity driver block 391 that displays the characteristics of the conductivity driver. Block 392 shows the characteristics of the thermistor interface and block 393 shows the characteristics of the optical interface. The control module may include a controller or microprocessor having similar features to those shown in
In some embodiments, the microprocessor may have one or more of the following features: 2.4GHz or another suitable frequency radio (integrated or external); a provided Bluetooth software stack; an SPI interface; USB (or UART for external USB drivers); I2C; 3, channel PWM; 32 GPIO; or a 6-channel ADC. In some embodiments, the device may require at least 48I/O pins or possibly more due to stack limitations. The bluetooth stack typically requires-20 kB of onboard flash memory, and thus would require at least 32 kB. In some embodiments, 64kB may be required if complex data processing is considered. The processor core may be an ARMCortex M4 or similar processor core. In some embodiments, the components may include STM32L433LC or STM32F302R8 of ST, which may require external radio, or the Kinetis KW family of NXP that includes integrated radio.
In some embodiments, the control module may include a memory component, wherein the amount of local memory depends on the sampling rate and resolution of the sensor. For example, a serial flash memory device using many manufacturers (Micron, spread) may meet an estimated data requirement of 256Mb (32 Mb).
The control module may use one or more analog switches. In some embodiments, analog switches with good on-resistance and reasonable bandwidth may be used. For example, ADG72 from Analog Device or NX3L4051HR from NXP may be used. Based on the initial system architecture, 8 of these would be needed.
The control module may include a power source, such as a battery. For example, a 300 mWh/day cell may be used. This was 2100mWh for 7 days. This may be provided by: 10 days, non-rechargeable, ER14250(14.5mm diameter × 25mm) LiSOCl2 cell; or 7 days, rechargeable, Li 14500(14.5mm diameter × 500mm) lithium ion battery.
The control module may comprise a Real Time Clock (RTC). The RTC may be selected from any RTC device with a crystal. The control module may also include various resistors, capacitors, connectors, charge controllers, and other power sources.
The PCB of the control module may be 4-layer board, approximately 50mm by 20mm, or 25mm by 40 mm. The type of PCB used depends largely on the connection requirements for the sensor array.
The housing of the control module may be a two-part moulding with a clip feature to allow easy access for replacement of the sensor array or battery.
Data collected by the sensor array may be passed through the control module and processed by host software. The software may be executed on a processing device. The processing device may be a PC, tablet, smartphone or other computer capable of running host software. The processing device executing the software may communicate with the control module via wires or via wireless communication. In some embodiments, the software may be configured to provide access to data stored on the control module, but not to perform big data analysis. The host software may include an interface to the control module via bluetooth or USB. In some embodiments, the host software may read the state of the control module, download logged data from the control module, upload sample rate control to the control module, convert data from the control module into a format suitable for processing by a big data analysis engine, or upload data to the cloud for processing by the analysis engine.
The software may be developed for PCs (Windows/Linux), tablets or smart phones (Android/iOS) or multiple platforms.
In some embodiments, a negative pressure source (e.g., a pump) and some or all of the other components of the local negative pressure system, such as a power source, sensors, connectors, user interface components (e.g., buttons, switches, speakers, screens, etc.), etc., may be integral with the wound dressing. In some embodiments, the component may be integrated below, within, on top of, or near the backing layer. In some embodiments, the wound dressing may include a second cover layer or second filter layer for positioning over the layers and any integrated components of the wound dressing. The second cover layer may be the uppermost layer of the dressing or may be a separate envelope enclosing the integrated components of the local negative pressure system.
An upper, top or upper layer as used herein refers to the layer that is furthest from the skin or surface of the wound when the dressing is in use and positioned over the wound. Thus, a lower surface, layer, sub-layer or layer refers to the layer closest to the skin or surface of the wound when the dressing is in use and positioned over the wound.
Component positioning
In some embodiments, electrical or electronic components (e.g., sensors, connections, etc.) may be placed or positioned on or embedded in one or more wound dressing components that may be placed in or on the wound, skin, or both the wound and skin. For example, one or more electronic components may be positioned on the wound-contacting layer side facing the wound, e.g., lower surface 224 of wound-contacting layer 222 in fig. 1B. The wound contact layer may be flexible, elastic or stretchable or substantially flexible, elastic or stretchable to conform to or cover the wound. For example, the wound contact layer may be made of a stretchable or substantially stretchable material, such as one or more of the following: polyurethanes, Thermoplastic Polyurethanes (TPU), silicones, polycarbonates, polyethylenes, polyimides, polyamides, polyesters, polystyrene tetramers (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), Polyetherimide (PEI), along with various Fluoropolymers (FEP) and copolymers, or other suitable materials. In some cases, one or more electronic components may alternatively or additionally be placed or positioned on or embedded in any one or more of the transmission layer, the absorbent layer, the backing layer, or any other suitable layer of the wound dressing.
In some embodiments, while it may be desirable for the wound contact layer to be stretchable to better fit or cover the wound, at least some of the electronic components may not be stretchable or flexible. In such cases, when the wound is bandaged with the wound dressing with the wound contact layer in or over the wound, undesirable or excessive local strains or stresses may be imposed on the one or more electronic components, for example on the support area or mounting of the electronic component. For example, such stress may be due to patient movement, changes in the shape or size of the wound (e.g., due to healing thereof), and the like. Such stress may cause movement, shifting, or failure of one or more electronic components (e.g., disconnection from a pin or another connector creating an open circuit). Alternatively or additionally, it may be desirable to maintain the position of one or more electronic components (e.g., one or more sensors) at the same or substantially the same location or area on the wound contact layer relative to the wound (e.g., in contact with the wound) such that measurements collected by the one or more electronic components accurately capture changes over time in the same or substantially the same location or area of the wound. Although the surface of the retractable wound contact layer may move when, for example, the patient moves, it may be desirable for one or more electronic components to be located in the same location or region relative to the wound.
As described herein, in some embodiments, one or more rigid, rigid or non-stretchable or substantially rigid, rigid or non-stretchable regions, such as one or more non-stretchable or substantially non-stretchable regions of material, may be mounted, positioned or disposed on the wound contact layer (or another suitable wound dressing component) for supporting one or more electronic components. Mounting, positioning, or disposing the one or more electronic components in the one or more non-stretchable or substantially non-stretchable regions may prevent the formation of localized stresses or help maintain the position of the one or more electronic components relative to the wound. In some cases, one or more electronic components may alternatively or additionally be flexible, e.g., mounted or printed on or supported by one or more flexible materials. For example, flexible plastic sheets or substrates such as polyimide, Polyetheretherketone (PEEK), polyester, silicone, and the like may be used.
Fig. 4A-4C illustrate a wound dressing 400 having a plurality of electronic components, according to some embodiments. As shown, the sheet or
Fig. 4B shows the components positioned on the
In some embodiments, perforations are made or patterned around one or more components (e.g.,
Fig. 4C illustrates optional application of a
One or more adhesive pads, traces or
In some embodiments, one or more adhesive regions may be patterned to position or adhere a particular component into a particular region, area or location in contact with or relative to the wound even when the
In certain embodiments, the pattern of bond regions may be based on the positioning of one or more electronic components, which may be determined using indexing as described herein. As explained herein, it may be desirable to pattern the adhesive to equalize stress or strain on the wound contact layer. The adhesive may be patterned to reinforce or support certain areas or regions, for example, areas where one or more electronic components are placed, while weakening (or reducing rigidity) other areas to distribute stress or avoid straining one or more electrical components. For example, it may be desirable to cover at least 50% or more of the wound-facing surface of the wound-contacting layer with adhesive. In certain embodiments, the adhesive may be applied to cover or substantially cover the entire wound-facing side of the wound-contacting layer.
In some embodiments, the adhesive material used to form the one or more adhesive regions may be non-stretchable or substantially non-stretchable. One or more regions of non-stretchable or substantially non-stretchable material (e.g.,
Although a single
Component packaging and stress relief
As described herein, the biocompatible coating can be applied to the wound contact layer or an electronic component positioned on the wound contact layer. In some embodiments, the wound contact layer comprises a thin flexible substrate that conforms to the wound. For example, the substrate may be made of a stretchable or substantially stretchable material or film, such as polyurethane, TPU, silicone, polycarbonate, polyethylene, polyimide, polyamide, polyester, PET, PBT, PEN, PEI, as well as various FEPs and copolymers or another suitable material. The substrate may not be biocompatible. The coating may be flexible. The coating can include one or more suitable polymers, binders, such as 1072-M binders (e.g., Dymax 1072-M), 1165-M binders (e.g., NovaChem Optimax 8002-LV, Dymax 1165-M, etc.), 10901-M binders (e.g., Dymax 1901-M or 9001-E Dymax), parylene (such as parylene C), silanes, epoxies, urethanes, acrylic urethane substitutes (e.g., HenkelLoctite 3381), or other suitable biocompatible and substantially stretchable materials. The coating may be a thin coating, for example from about 80 microns or less to several millimeters or more. As described herein, the coating may be applied by one or more of lamination, adhesion, welding (e.g., ultrasonic welding), curing by light, UV, heat, and the like. The coating may be transparent or substantially transparent to allow optical detection. The coating can maintain bond strength when subjected to sterilization, such as EtO sterilization. The coating may have a hardness of less than about a100, a80, a50, or less. The coating may have an elongation at break of greater than about 100%, 200%, 300%, or more. The coating may have a viscosity of about 8,000 and 14,500 centipoise (cP). In some cases, the coating may have a viscosity of no less than about 3,000 cP. In some cases, the coating may have a viscosity of less than about 3,000 cP. The coating may be fluorescent.
It may be desirable for the substrate and the electronic components supported by the substrate to be conformable because the substrate and the electronic components are intended to be positioned on or in the body. One property of conformability is the extensibility of the coating material, as the electronic components may need to be isolated from the wound. A coating applied to a substrate may need to have the ability to stretch with the substrate (in the case where the substrate is stretchable or substantially stretchable). Pairing the elongated characteristics of both the substrate and the coating maximizes the desired characteristics of the device. In some examples, the substrate may be formed from a TPU film. The coating may be formed of acrylic urethane (e.g., 1165-M Dymax, 1072-MDymax) or another suitable material as described herein.
It may be desirable to uniformly and thoroughly coat the substrate (e.g., the substrate may be encapsulated by a biocompatible coating). The substrate (e.g., TPU) may be hydrophilic and thus may need to be encapsulated in a hydrophobic coating to form a hydrophobic dressing to be placed on or in a wound.
Fig. 5A-5B illustrate coatings of wound dressings according to some embodiments. As described herein, one side of the
As shown in fig. 5B, a
Fig. 6 illustrates a wound dressing having two biocompatible coatings according to some embodiments. The
The non-stretchable or substantially non-stretchable coatings described herein, such as
As shown,
In some embodiments, the non-stretchable or substantially non-stretchable coating may not be biocompatible. As shown in fig. 7, the
Coating a thin flexible substrate with a biocompatible material is important because it may be necessary to coat the substrate on the side where the electronic components are located and on the opposite side. In addition, it may be desirable to uniformly and thoroughly coat the substrate (e.g., the substrate may be encapsulated by a biocompatible coating).
In some embodiments, an
In some embodiments, the coating may be applied thin and uniformly. For example, the coating may be sprayed. In some embodiments, a biocompatible coating may be applied to the wound contact layer by the apparatus 600 of fig. 9. As shown, the
As described herein, one side of the wound contact layer may include a plurality of electronic components protruding from the surface. This is illustrated, for example, in fig. 4A-4C, where the
In certain embodiments,
In some embodiments, the mold may include a
Fig. 11 and 12A-12B illustrate an
The
In the arrangement shown, a substrate (not shown) may be positioned to place the side supporting the electronic component on the
In some embodiments, the side of the substrate supporting the electronic component is coated first. The apparatus 500 (without a mold) or the apparatus 800 (with a mold) may be used to hold the substrate between the
In some embodiments, a rigid or substantially rigid release layer or
In certain embodiments,
In some embodiments, as shown in fig. 14A-14B, a mold of the wound contact layer may be cast to enable the wound contact layer to remain flat or substantially flat during application. As shown in fig. 14A, a
Fig. 14B shows coating a
One side of the
As described herein, in some embodiments, acrylic urethanes can be used as coating materials because these polymers have suitable adhesion and extensibility. Spraying the acrylic urethane with compressed air or inert gas may cause oxygen inhibition of the polymerization reaction to cure the acrylic urethane. The removal of oxygen from the system results in the elimination of negative effects on the polymerization reaction to cure the acrylic urethane.
Fig. 15 illustrates spraying a wound dressing according to some embodiments. The
In some embodiments, a non-stretchable or substantially non-stretchable coating may be applied to at least some of the plurality of electronic components. Fig. 16 illustrates applying a non-stretchable material to a wound dressing according to some embodiments. The
In some embodiments, a single layer of stretchable or non-stretchable coating may be applied. In some embodiments, multiple layers of stretchable or non-stretchable coatings may be applied. For example, multiple layers of non-stretchable coatings may be applied to achieve a desired stiffness or rigidity.
17A-17B illustrate a comparison of performance with and without a non-stretchable material according to some embodiments. Fig. 17A shows how much an electrical connection that is not coated with a non-stretchable or substantially non-stretchable coating can be stretched. Stretching may be caused, for example, by movement of the patient.
Fig. 17B shows how much the electrical connection coated with a non-stretchable or substantially non-stretchable coating is stretchable. As shown, the uncoated electrical connection 410A and the coated electrical connection 410C are approximately the same length when unstretched. However, uncoated electrical connection 410B stretches to a much greater length than coated electrical connection 410D.
In some embodiments, the wound dressings described herein may need to comply with one or more safety standards, for example, the IEC60601 standard for safety and effectiveness of medical electrical equipment. Such one or more criteria may require highly stringent testing methods to ensure electrical safety of the wound dressing. Coatings described herein, such as
In some embodiments, the coating may comprise one or more pre-existing materials, such as a film. As described herein, such pre-existing materials may be manufactured or tested to comply with one or more applicable safety standards, such as the IEC60601 standard, and then one or more materials are applied to a substrate. In certain embodiments, the pre-existing material may be TPU, acrylic, or another material.
In some embodiments, a coating may be applied over the electronic component, which may subject the coating to localized thinning or stretching. This may be due to the surface irregularities of the substrate resulting from the placement of the electronic components. In some cases, localized thinning or stretching may be present or may be detected when the coating is not sprayed.
In certain embodiments, an electromagnetic/radio frequency shield may be applied to the coated surface to protect the electronic components from electromagnetic interference. For example, conductive inks may be used. The ink may be silicone, silver, or the like.
Component packaging and stress relief for perforated substrates
In some embodiments, the
Fig. 18 shows a wound dressing 1800 with one or more perforations according to some embodiments. The illustrated
Any of the one or
Fig. 19B illustrates a
As shown in fig. 19B, one or more of the
In some embodiments, one or more release liners may be used during the manufacture or coating of the
Any one or more of
Other variants
In some embodiments, the one or more electronic components may be positioned on a side of the wound contact layer opposite the wound-facing side. The systems and methods described herein are equally applicable to such wound contact layers. Although spray coating is described above, other suitable methods for applying the coating may be used in certain embodiments. Such methods may include one or more of the following: dip coating, spin coating, vapor deposition, chemical deposition, electrochemical deposition, roll-to-roll coating, lamination, adhesion, welding (e.g., ultrasonic welding), curing by one or more of light, UV, heat, and the like.
While certain embodiments described herein relate to wound dressings, the systems and methods disclosed herein are not limited to wound dressings or medical applications. The systems and methods disclosed herein are generally applicable to electronic devices, e.g., electronic devices that may be worn or applied to a user.
Any values of thresholds, limits, durations, etc. provided herein are not intended to be absolute, and thus may be approximate. Further, any thresholds, limits, durations, etc. provided herein may be fixed or changed automatically or by a user. Further, relative terms such as exceeding, greater than, less than, etc., relative to a reference value, as used herein, are intended to also encompass being equal to the reference value. For example, exceeding a positive reference value may include being equal to or greater than the reference value. Further, relative terms such as above, greater than, less than, and the like, as used herein with respect to a reference value, are also intended to encompass the inverse of the disclosed relationship, such as below, less than, greater than, and the like, with respect to the reference value. Further, while blocks of various processes may be described in terms of determining whether a value meets or does not meet a particular threshold, these blocks may be similarly understood, e.g., in terms of values (i) that are below or above the threshold or (ii) that meet or do not meet the threshold.
Features, materials, characteristics, or groups described in connection with a particular aspect, embodiment, or example are understood to apply to any other aspect, embodiment, or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features or steps are mutually exclusive. The protection is not restricted to the details of any of the foregoing embodiments. Any novel feature or any novel combination of features disclosed in this specification (including any accompanying claims, abstract and drawings), or any novel feature or any novel combination of steps of any method or process so disclosed, is claimed.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of protection. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made. Those of skill in the art will understand that in some embodiments, the actual steps taken in the processes shown or disclosed may differ from those shown in the figures. According to embodiments, some of the steps described above may be eliminated, and other steps may be added. For example, the actual steps or sequence of steps taken in the disclosed processes may differ from those shown in the figures. According to embodiments, some of the steps described above may be eliminated, and other steps may be added. For example, the various components shown in the figures may be implemented as software or firmware on a processor, controller, ASIC, FPGA, or dedicated hardware. Hardware components, such as controllers, processors, ASICs, FPGAs, etc., may comprise logic circuitry. Furthermore, the features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure.
While the present disclosure includes certain embodiments, examples, and applications, it will be understood by those skilled in the art that the present disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments or uses and obvious modifications and equivalents thereof, including embodiments that do not provide all of the features and advantages described herein. Accordingly, the scope of the present disclosure is not intended to be limited by the specific disclosure of the preferred embodiments herein, and may be defined by the claims set forth herein or by claims set forth in the future.
Conditional language, such as "can," "might," or "may," unless expressly stated otherwise or understood otherwise in the context of usage, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain functions, elements, or steps. Thus, such conditional language is not generally intended to imply that features, elements, or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, or steps are included or are to be performed in any particular embodiment. The terms "comprising," "including," "having," and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and the like. Furthermore, the term "or" is used in its inclusive sense (and not in its exclusive sense) so that, when used, e.g., to connect a list of elements, the term "or" means one, some, or all of the elements in the list. Further, the term "each" as used herein may mean any subset of a set of elements to which the term "each" applies, except having its ordinary meaning.
Joint language such as the phrase "X, Y and at least one of Z" is understood in this context to generally mean that an item, term, etc. can be X, Y or Z unless explicitly stated otherwise. Thus, such conjunctive language is not meant to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z in general.
The terms "about," "approximately," "substantially," and "approximately" as used herein mean a value, amount, or characteristic that is close to a stated value, amount, or characteristic, that still performs the desired function or achieves the desired result. For example, the terms "about," "substantially," and "substantially" may refer to an amount within less than 10%, within less than 5%, within less than 1%, within less than 0.1%, and within less than 0.01% of the specified amount. As another example, in certain embodiments, the terms "substantially parallel" and "substantially parallel" refer to a value, amount, or characteristic that deviates from exactly parallel by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degrees.
The scope of the present disclosure is not intended to be limited by the particular disclosure of the preferred embodiments in this section or elsewhere in this specification, and may be defined by claims set forth in this section or elsewhere in this specification or in the future. The language of the claims is to be construed broadly based on the language employed in the claims and not limited to examples described in the specification or during the prosecution of the application, which examples are to be construed as non-exclusive.