Wound dressing with impedance sensor

Patent metadata

Field	Value
Publication number	US-10716490-B2
Application number	US-201013379309-A
Country	US
Kind code	B2
Filing date	Jul 9, 2010
Priority date	Jul 10, 2009
Publication date	Jul 21, 2020
Grant date	Jul 21, 2020

Abstract

A wound sensor comprising at least one electrode (10a, 10b) and a non-adherent porous layer (25) proximate at least part of the electrode.

First claim

The invention claimed is:

1. A wound sensor comprising:
at least one electrode and an external measurement device coupled or configured to couple with the at least one electrode, the external measurement device being configured to receive electrical measurement signals from the at least one electrode and to determine impedance of a wound or wound fluid using the received electrical measurement signals, the at least one electrode having a sensing surface and a signal carrying portion, the signal carrying portion being configured for carrying the electrical measurement signals from the sensing surface to the external measurement device, the signal carrying portion and the sensing surface both being disposed on an electrically insulating substrate having insulating properties during use of the wound sensor;
an insulating layer that covers said signal carrying portion, such that said signal carrying portion is positioned between the substrate and the insulating layer; and a non-adherent porous layer in direct contact with the sensing surface, wherein:
said sensing surface is positioned between the substrate and the non-adherent porous layer that is in direct contact with the sensing surface, such that the non-adherent porous layer that is in direct contact with the sensing surface and the substrate at least partly define a bounded volume in which the sensing surface is provided; and
the non-adherent porous layer directly overlies and contacts the sensing surface, forms a wound contact surface, and collects a volume of wound fluid within the bounded volume that is measurable by the external measurement device using the at least one electrode to determine the impedance.

2. A wound sensor according to claim 1 , wherein the non-adherent porous layer is a biocompatible and/or non-irritant surface, material or coating.

3. A wound sensor according to claim 1 , wherein the sensor comprises two or more electrodes.

4. A wound sensor according to claim 1 , wherein the at least one electrode is printed.

5. A wound sensor according to claim 1 , wherein the non-adherent porous layer is separate from the at least one electrode.

6. A wound sensor according to claim 1 , wherein the non-adherent porous layer fully covers the at least one electrode.

7. A wound sensor according to claim 1 , wherein the non-adherent porous layer is non-conducting.

8. A wound sensor according to claim 1 , wherein the non-adherent porous layer is adjacent to at least part of the at least one electrode.

9. A wound sensor according to claim 1 , wherein the sensor is arranged such that the non-adherent porous layer is provided on an opposite side of the at least one electrode to the substrate.

10. A wound sensor according to claim 1 , wherein the non-adherent porous layer comprises silicone.

11. A wound sensor according to claim 1 , wherein the non-adherent porous layer comprises a cellulosic material.

12. A wound sensor according to claim 1 , wherein the non-adherent porous layer is between 50 500 pm thick.

13. A wound sensor according to claim 1 , wherein the sensing surface is configured for taking electrical measurements.

14. A wound sensor according to claim 1 , wherein the at least one electrode comprises a biocompatible material.

15. A wound sensor according to claim 1 , wherein the at least one electrode is selected from the group consisting of silver, a silver compound, and silver chloride.

16. A wound sensor according to claim 1 , wherein the at least one electrode is at least partially formed from conductive ink.

17. A wound sensor according to claim 1 , wherein the at least one electrode is elongated.

18. A wound sensor according to claim 1 , wherein at least part of a signal carrying portion of the at least one electrode is provided between the substrate and the insulating layer and the sensing surface is not covered by the insulating layer.

19. A wound sensor according to claim 1 , wherein the insulating layer is at least one of adhered to or pressed together with or integral with the substrate around a signal carrying part of the at least one electrode.

20. A wound sensor according to claim 1 , wherein the substrate or the insulating layer comprise a biocompatible, flexible polymer film.

21. A wound sensor according to claim 1 , wherein at least one of the substrate and the insulating layer comprises a polyolefin film.

22. A wound sensor according to claim 21 , wherein the substrate or the insulating layer is at least partially coated with an adhesive.

23. A wound sensor according to claim 1 , wherein the substrate is between 0.075 mm and 1 mm thick.

24. A wound sensor according to claim 1 , wherein the wound sensor is arranged to be used with a wound dressing.

25. A wound sensor according to claim 24 , wherein the wound sensor is arranged such that, in use, the substrate faces the wound dressing, whilst the non-adherent porous layer and the exposed sensing surface of the at least one electrode face the wound.

26. A wound sensor according to claim 1 , wherein each of the sensing surface of the at least one electrode are arranged to perform electrical stimulation of the wound.

27. A wound sensor according to claim 1 , wherein a pair of electrodes is adapted to measure wound hydration.

28. A wound sensor as claimed claim 1 , wherein the at least one electrode comprises a signal measurement part connected to the signal carrying portion for allowing communication of measurements from the signal measurement part.

29. A wound sensor as claimed in claim 28 , wherein the signal carrying portion of the at least one electrode is substantially electrically insulated from the wound environment.

30. A wound sensor as claimed in claim 28 , wherein the signal carrying portion is covered by an electrically insulating layer.

31. A wound sensor according to claim 10 , wherein the non-adherent porous layer comprises a silicone coating.

32. A wound sensor according to claim 12 , wherein the non-adherent porous layer has pore sizes in the range of 20-500 pm.

33. A wound sensor according to claim 19 , wherein the insulating layer is pressed together with the substrate around the signal carrying part of the electrode.

34. A wound sensor according to claim 19 , wherein the insulating layer is integral with the substrate around the signal carrying part of the at least one electrode.

35. A wound sensor according to claim 21 , wherein the polyolefin film is a polyethylene film.

36. A wound sensor according to claim 22 , wherein the adhesive is an acrylic adhesive.

37. A wound sensor according to claim 1 , wherein the at least one electrode is planar.

38. A wound sensor according to claim 1 , wherein the electrically insulating substrate is either a biocompatible, flexible polymer film or a polyolefin film.

39. A wound sensor according to claim 1 , wherein at least one of:
the signal carrying portion is sandwiched between the insulating layer and the electrically insulating substrate;
the insulating layer is bonded to the electrically insulating substrate around the signal carrying portion; or
the insulating layer and the electrically insulating substrate are both trimmed close to the at least one

Assignees

• Connolly Patricia
• Univ Strathclyde

Inventors

• Connolly Patricia

Classifications

• A61F2013/00961

  electrical conductivity · CPC title

• A61F2013/00442

  using electrodes · CPC title

• A61F2013/00204

  insulating · CPC title

• A61F13/0276

  Apparatus or processes for manufacturing adhesive dressings or bandages · CPC title

• A61B2562/0215

  Silver or silver chloride containing · CPC title