Wound healing sensor techniques

• US 8,535,282 B2
• Filed: 07/14/2009
• Issued: 09/17/2013
• Est. Priority Date: 07/14/2009
• Status: Active Grant

• Current Assignee: Southwest Research Institute
• Original Assignee: Southwest Research Institute
• Inventors: Hanson, Heather S., Nitin, Nitin
• Primary Examiner(s): HAND, MELANIE JO
• Application Number:
  US12/502,926
• Publication Number:
  US 20110015591A1
• Time in Patent Office: 1,526 Days
• Field of Search: 604 8- 10, 604/313, 604/319, 435/4, 435/5, 435/6.17, 435/286.5, 435/287.1, 435/287.5, 435/288.4, 435/288.5, 435/288.7, 422 8205- 8209, 422/83, 422 85- 87, 422/91, 422/98, 422/502, 422/503, 422/507
• US Class Current: 604/313
• CPC Class Codes: A61B 10/0045 Devices for taking samples of body liquids devices for taking blood samples A61B5/15
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150099 by negative pressure, other than vacuum extraction into a syringe by pulling on the piston rod or into pre-evacuated tubes
• CPC Class Codes: A61B 5/150221 Valves
• CPC Class Codes: A61B 5/150251 Collection chamber divided into at least two compartments, e.g. for division of samples injection syringes having more than one chamber A61M5/19; syringes for injection of two or more media A61M5/2448, A61M5/284; sample preparation for further analysis A61B5/150755
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• CPC Class Codes: A61B 5/151 Devices specially adapted for taking samples of capillary blood, e.g. by lancets , needles or blades
• CPC Class Codes: A61B 5/155 Devices specially adapted for continuous or multiple sampling, e.g. at predetermined intervals devices loaded with multiple lancets simultaneously A61B5/15146
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: A61B 5/445 Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
• CPC Class Codes: A61M 1/73 comprising sensors or indicators for physical values
• CPC Class Codes: A61M 1/743 by changing the cross-section of the line, e.g. flow regulating valves A61M1/7413 takes precedence
• CPC Class Codes: A61M 1/782 using valves with freely moving parts, e.g. float valves
• CPC Class Codes: A61M 1/95 with sensors for exudate composition
• CPC Class Codes: A61M 2205/3303 Using a biosensor
• CPC Class Codes: A61M 2205/3324 PH measuring means
• CPC Class Codes: B33Y 80/00 : Products made by additive manufacturing

Abstract

The present disclosure is directed at methods and apparatus to evaluate and monitor healing progress of wound and/or to generate data to modify or identify a treatment protocol. Fluid exudate removed from the wound by a negative pressure therapy device may now be analyzed to identify the progress of wound healing, such as whether healing is progressing in a positive manner or experiencing one or more impediments. The fluid exudates may be specifically analyzed for one or more analytes indicative of one or more of the biochemical reactions that may occur during wound recovery. In addition, one may separately utilize optical sensors integrated into a dressing enclosure, optionally in those dressings employed in a negative pressure therapy device. Such optical sensors may then illuminate the wound and collect information regarding the wound via a light scattering type response.

Claims

1. An apparatus to evaluate and monitor healing progress of a wound and to generate data to modify or identify a treatment protocol comprising:

a dressing enclosure for administering reduced pressure treatment to a wound, wherein the enclosure is configured to cover the wound and to maintain reduced pressure at the wound location;

a device capable of supplying reduced pressure;

a microfluidic device including a closed-channel continuous flow system connected between said dressing enclosure for said wound and said device capable of supplying reduced pressure to withdraw fluid exudates containing one or more analytes from said wound wherein said microfluidic device includes first and second compartments wherein in said first compartment an analyte that is one of said one or more analytes binds with one or more labeled antibodies or aptamers and in a second compartment the bound analyte is detected; and

a sensor in said second compartment of said microfluidic device capable of analyzing said fluid exudates for one or more analytes indicative of said progress of wound healing and said analyzing of said fluid exudates is done continuously without disruption of said reduced pressure at said wound location and providing real time analysis of wound healing and providing real-time treatment protocol adjustments.

2. The apparatus of claim 1 wherein said closed-channel continuous flow system includes flow passages having a width or dept of 1 μ

m to 500 μ

m and wherein said exudate fluid is configured to flow in said flow passages at a rate of 1 μ

L/min to 100 μ

L/min.

3. The apparatus of claim 1 wherein said sensor analyzes said fluid exudate and provided an indication of fluid pH.

4. The apparatus of claim 1 wherein said sensor analyzes said fluid exudate and provides an indication of fluid oxygen level.

5. The apparatus of claim 1 wherein said sensor analyzes said fluid exudates for the presence of wherein said sensor analyzes said fluid exudates for the presence of one or more of the following:

biomarkers of active bacterial infection, pro-inflammatory cytokines, proteases, and tissue growth factors.

6. The apparatus of claim 1 wherein a pH sensitive chromophore is introduced into said microfluidic device.

7. The apparatus of claim 1 wherein an oxygen sensitive chromophore is introduced into said fluid trap.

8. The apparatus of claim 1 wherein said sensor analyzes said fluid exudates for the presence of one or more of the following:

biomarkers of active bacterial infection, pro-inflammatory cytokines, proteases, and tissue growth factors.

9. The apparatus of claim 1 wherein said sensor analyzes said fluid exudate for matrix metallo proteinase.

10. The apparatus of claim 1, further including an optical sensor in said dressing enclosure, wherein said optical sensor is configured to provide varying wavelengths of light to said wound location.

11. The apparatus of claim 1 wherein said optical sensor is configured to provide light at wavelengths of 350 nm to 700 nm.

12. The apparatus of claim 1 wherein said optical sensor is configured to provide light at wavelengths of 600 nm to 1400 nm.

13. A method to evaluate and monitor healing progress of a wound via analysis of wound fluid exudate comprising:

locating a dressing enclosure for administering reduced pressure treatment to a wound at a wound location, wherein said enclosure is configured to cover said wound and to maintain reduced pressure at the site of the wound;

supplying a device that provides reduced pressure to said dressing enclosure;

locating a microfluidic device including a closed-channel continuous flow system between said dressing enclosure for said wound and said device capable of supplying reduced pressure;

withdrawing fluid exudate from said wound containing one or more analytes wherein said microfluidic device includes first and second compartments wherein in said first compartment an analyte that is one of said one or more analytes binds with one or more labeled antibodies or aptamers and in a second compartment the bound analyte is detected;

supplying a sensor in said second compartment of said microfluidic device capable of analyzing said fluid exudates for one or more analytes indicative of the progress of said wound healing and said analyzing of said fluid exudates is done continuously without disruption of said reduced pressure at said wound location; and

identifying one or more of said analytes and providing real time analysis of wound healing and providing real-time treatment protocol adjustments.