SYSTEMS AND METHODS FOR ELECTRICALLY DETECTING THE PRESENCE OF EXUDATE IN DRESSINGS

• US 20120016322A1
• Filed: 07/14/2011
• Published: 01/19/2012
• Est. Priority Date: 07/19/2010
• Status: Active Grant

• Current Assignee: Solventum Intellectual Properties Company (Solventum Corp.)
• Original Assignee: KCI Licensing Incorporated (3M Company)
• Inventors: Coulthard, Richard Daniel John, Thomson, Malcolm, Jaeger, Rico
• Granted Patent: US 8,795,257 B2
• Time in Patent Office: Days
• US Class Current: 604/319
• CPC Class Codes: A61F 13/00055 Saturation indicators
• CPC Class Codes: A61F 13/02 Adhesive bandages or dressings
• CPC Class Codes: A61F 13/0206 with absorbent fibrous layers, e.g. woven or non-woven absorbent pads or island dressings
• CPC Class Codes: A61F 13/05 specially adapted for use with sub-pressure or over-pressure therapy, wound drainage or wound irrigation, e.g. for use with negative-pressure wound therapy [NPWT]
• CPC Class Codes: A61F 2013/00174 possibility of applying pressure
• CPC Class Codes: A61F 2013/00421 with double adhesive layer with cyano-acrylic adhesive A61F2013/00459; with adhesive connecting means A61F2013/00561; adhesives for plasters A61F2013/00655; with absorbent adhesives A61F2013/00757; with permeable adhesive layers A61F2013/00761; different adhesion of different adhesive layers A61F2013/00804; changing the adhesion force with strain value A61F2013/00838
• CPC Class Codes: A61F 2013/00536 for draining or irrigating wounds
• CPC Class Codes: A61F 2013/0054 for deep wounds
• CPC Class Codes: A61F 2013/00961 electrical conductivity
• CPC Class Codes: A61M 1/73 comprising sensors or indicators for physical values
• CPC Class Codes: A61M 1/74 Suction control underwater drainage A61M1/61
• CPC Class Codes: A61M 1/784 by filtering, sterilising or disinfecting the exhaust air, e.g. swellable filter valves
• CPC Class Codes: A61M 1/912 Connectors between dressing and drainage tube
• CPC Class Codes: A61M 1/962 having pumping means on the suction site, e.g. miniature pump on dressing or dressing capable of exerting suction
• CPC Class Codes: A61M 1/964 having venting means on or near the dressing
• CPC Class Codes: A61M 1/966 having a pressure sensor on or near the dressing
• CPC Class Codes: A61M 1/982 with means for detecting level of collected exudate
• CPC Class Codes: A61M 1/985 the dressing itself forming the collection container
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/3317 : Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3341 : stabilising pressure or flow to avoid excessive variation
• CPC Class Codes: A61M 2205/3344 : Measuring or controlling pressure at the body treatment site
• CPC Class Codes: A61M 2205/3569 : sublocal, e.g. between console and disposable
• CPC Class Codes: A61M 2205/3592 : using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 2205/581 : by audible feedback
• CPC Class Codes: A61M 2205/583 : by visual feedback
• CPC Class Codes: A61M 2205/6081 : Colour codes
• CPC Class Codes: A61M 27/00 : Drainage appliance for wounds or the like , i.e. wound drains, implanted drains negative pressure wound therapy devices A61M1/90; implements for holding wound open A61B17/02 ; middle ear drainage A61F11/202
• CPC Class Codes: G08B 21/20 : responsive to moisture

Abstract

Systems and methods are provided for sensing fluid in a dressing on a patient and producing an electrical signal. In one instance, a galvanic cell is used as an electronic detection device. The galvanic cell is placed in the dressing and produces voltage when the dressing is substantially saturated. In one instance, the dressing is a reduced-pressure, absorbent dressing. Other systems, methods, and dressings are presented.

Claims

1. A dressing for receiving an ionic fluid, the dressing comprising:

an absorbent layer for placing in fluid communication with the tissue site and for receiving and at least temporarily retaining ionic fluids, the absorbent layer having a first side and a second, patient-facing side;

a sealing member for covering the absorbent layer;

a first galvanic cell associated with the absorbent layer and configured to produce a voltage when the absorbent layer proximate to the first galvanic cell is substantially saturated with the ionic fluid.

2. The dressing of claim 1, wherein the galvanic cell comprises:

a first electrode and a second electrode, the first electrode and second electrode in fluid communication with a portion of the absorbent layer, and the first electrode and second electrode spaced from one another;

a first electrical lead coupled to the first electrode;

a second electrical lead coupled to the second electrode; and

wherein the first electrode and second electrode are configured to produce measurable electrical power when the ionic fluid covers the first electrode and second electrode.

3. The dressing of claim 2, wherein the first electrode comprises copper and the second electrode comprises tin.

4. The dressing of claim 2, wherein the first electrode comprises copper and the second electrode comprises tin, and wherein the ionic fluid comprises exudate from a patient.

5. The dressing of claim 2, wherein the first electrode comprises copper and the second electrode comprises zinc.

6. The dressing of claim 1, further comprising a plurality of galvanic cells associated with the absorbent layer and configured to provide power proportional to the saturation of the absorbent layer of the dressing.

7. The dressing of claim 1, further comprising a wireless-communication-and-power subsystem.

8. A system for treating a tissue site on a patient with reduced pressure, the system comprising:

an absorbent layer for placing proximate to the tissue site;

a sealing member for covering the dressing and a portion of the patient'"'"'s epidermis to form a fluid seal;

a reduced-pressure source fluidly coupled to the absorbent layer for providing reduced pressure to the absorbent layer;

a galvanic cell associated with the absorbent layer, wherein the galvanic cell is configured to produce power when the absorbent layer proximate to the galvanic cell is substantially saturated with an ionic fluid; and

a monitoring unit electrically coupled to the galvanic cell for receiving power from the galvanic cell.

9. The system of claim 8, wherein the monitoring unit is a comparator circuit.

10. The system of claim 8, wherein the monitoring unit comprises an analog-to-digital converter coupled to a microprocessor, and wherein the microprocessor is configured to develop an alarm signal when the power reaches a power threshold value.

11. The dressing of claim 8, wherein the galvanic cell comprises:

a first electrode and a second electrode, the first electrode and second electrode in fluid communication with a portion of the absorbent layer, and the first electrode and second electrode spaced from one another;

a first electrical lead coupled to the first electrode;

a second electrical lead coupled to the second electrode; and

wherein the first electrode and second electrode are configured to produce measurable electrical power when the ionic fluid covers the first electrode and second electrode.

12. The dressing of claim 8, wherein the first electrode comprises copper and the second electrode comprises tin.

13. The dressing of claim 8, wherein the first electrode comprises copper and the second electrode comprises tin, and wherein the ionic fluid comprises exudate from a patient.

14. The dressing of claim 8, wherein the first electrode comprises copper and the second electrode comprises zinc.

15. The dressing of claim 8, further comprising a plurality of galvanic cells associated with the absorbent layer and configured to provide power proportional to the saturation of the absorbent layer of the dressing.

16. The dressing of claim 8, wherein the monitoring unit comprises a electronic detection device and a wireless-communication-and-power subsystem.

17. A method for treating a tissue site, the method comprising:

providing a dressing, wherein the dressing comprises;

an absorbent layer for placing in fluid communication with the tissue site, the absorbent layer for receiving and retaining ionic fluids, the absorbent layer having a first side and a second, patient-facing side,

a sealing member for covering the first side of the absorbent layer, and

a first galvanic cell associated with the absorbent layer and configured to produce a voltage indicative of a full state when the absorbent layer proximate to the first galvanic cell is substantially saturated with the ionic fluid;

deploying the dressing proximate to the tissue site;

electrically coupling the first galvanic cell to a monitoring unit, wherein the monitoring unit is configured to produce a dressing-full signal when receiving the voltage indicative of a full state from the first galvanic cell; and

providing reduced pressure to the dressing until the monitoring unit provides the dressing-full signal.

18. The dressing of claim 17, wherein the galvanic cell comprises:

a first electrode and a second electrode, the first electrode and second electrode in fluid communication with a portion of the absorbent layer, and the first electrode and second electrode spaced from one another;

a first electrical lead coupled to the first electrode;

a second electrical lead coupled to the second electrode; and

wherein the first electrode and second electrode are configured to produce measurable electrical voltage when the ionic fluid covers the first electrode and second electrode.

19. The method of claim 17, wherein the first electrode comprises copper and the second electrode comprises tin.

20. The method of claim 17, wherein the first electrode comprises copper and the second electrode comprises tin, and wherein the ionic fluid comprises exudate from a patient.

21. The method of claim 17, wherein the first electrode comprises copper and the second electrode comprises zinc.

22. The method of claim 17, wherein the dressing further comprises a plurality of galvanic cells associated with the absorbent layer and configured to provide voltage proportional to the saturation of the absorbent layer of the dressing.

23. A dressing for treating a tissue site on a patient, the dressing comprising:

an absorbent layer for placing in fluid communication with the tissue site, the absorbent layer for receiving and retaining ionic fluids, the absorbent layer having a first side and a second, patient-facing side;

a sealing member for covering the absorbent layer; and

a conductive loop fluidly coupled to the absorbent layer and having a first terminal, a second terminal, and at least one conductive gap, wherein the conductive gap is sized and configured to be electrically bridged when covered with the ionic fluid.

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