Device for obtaining at least one constituent of a bodily fluid

• US 20030050575A1
• Filed: 08/27/2002
• Published: 03/13/2003
• Est. Priority Date: 02/29/2000
• Status: Abandoned Application

• Current Assignee: Roche Diagnostics International AG (Roche Holding AG)
• Original Assignee: Roche Diagnostics International AG (Roche Holding AG)
• Inventors: Haueter, Ulrich, Diermann, Ulrich
• Application Number:
  US10/229,904
• Publication Number:
  US 20030050575A1
• Time in Patent Office: Days
• US Class Current: 600/581
• CPC Class Codes: A61B 5/14528 invasively
• 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 5/150389 Hollow piercing elements, e.g. canulas, needles, for piercing the skin
• CPC Class Codes: A61B 5/150511 Details of construction of shaft
• CPC Class Codes: A61B 5/150984 Microneedles or microblades
• CPC Class Codes: A61B 5/15142 Devices intended for single use, i.e. disposable
• CPC Class Codes: A61M 2025/0042 Microcatheters, cannula or the like having outside diameters around 1 mm or less
• CPC Class Codes: A61M 2025/0057 Catheters delivering medicament other than through a conventional lumen, e.g. porous walls or hydrogel coatings
• 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

Abstract

The invention relates to a device for obtaining at least one constituent of a body fluid, using a cannula which projects from a lower side of the device and may be positioned in a body tissue, said device comprising a capillary layer having an exposed surface for evaporating the fluid and said cannula being connected to the capillary layer.

Claims

1. A device for obtaining at least one constituent of a body fluid, using a cannula which projects from a lower side of said device and may be positioned in a body tissue, wherein:

a) said device comprises a capillary layer having an exposed surface for evaporating said fluid; and

b) said cannula is connected to said capillary layer.

2. The device as set forth in claim 1, wherein said capillary layer comprises capillaries for transporting fluid to said exposed surface, said capillaries extending through said capillary layer generally perpendicularly to said exposed surface.

3. The device as set forth in claim 1, wherein said capillary layer comprises capillary channels extending at said exposed surface.

4. The device as set forth in claim 1, wherein said capillary layer comprises a fabric-like material

5. The device as set forth in claim 1, wherein said capillary layer contains a fabric.

6. The device as set forth in claim 1, wherein said capillary layer contains a fleece.

7. The device as set forth in claim 1, wherein said device is filled with a sterile, bio-compatible fluid before it is subcutaneously positioned.

8. The device as set forth in claim 1, wherein:

said device comprises a casing;

said cannula projects from a lower side of said casing; and

said capillary layer is associated with an upper side of said casing.

9. The device as set forth in claim 8, wherein said capillary layer is attached to the upper side.

10. The device as set forth in claim 8, wherein said capillary layer is formed integrally with said casing.

11. The device as set forth in claim 8, wherein said casing is connectable to a vessel which may be evacuated, such that said vessel encloses said exposed surface of said capillary layer and such that a space enclosed by said exposed surface and said vessel may be evacuated.

12. The device as set forth in claim 1, wherein:

said device is a micro perfusion device;

a casing of said device comprises a supply for a fluid perfusate;

said cannula projects from a lower side of said casing and when positioned for micro perfusion forms an outer cannula which surrounds an inner cannula;

said inner cannula forms an inner lumen between a front cannula opening which is distal with respect to said casing and a rear cannula opening, said inner lumen being connected or connectable to said supply via said rear cannula opening; and

an outer lumen remains between said inner cannula and said outer cannula which is connected to said front cannula opening and said capillary layer.

13. The device as set forth in claim 12, wherein:

said inner cannula has a longitudinal axis and is accommodated by said casing such that it may be slid from a front sliding position to a rear sliding position in the longitudinal direction; and

said inner cannula is an injection needle, which in its front sliding position protrudes out of said outer cannula and in its rear sliding position said outer cannula protrudes beyond it.

14. The device as set forth in claim 12, wherein said supply is connected to a variable-volume storage container for a perfusate.

15. The device as set forth in claim 14, wherein said storage container is flexible.

16. The device as set forth in claim 1, wherein said device is a micro filtration device.

17. The device as set forth in claim 1, wherein a sensor of a measuring means for measuring the concentration of said at least one constituent of said body fluid is arranged in a section of said device which said body fluid flows through, wherein after positioning the device, said section extends outside said body tissue from said cannula up to and including said exposed surface of said capillary layer.

18. The device as set forth in claim 1, wherein:

a measuring means for measuring the concentration of said at least one constituent of said body fluid comprises a working electrode and a counter electrode; and

said counter electrode is formed on said lower side of said device which contacts the skin once said inner cannula and said perfusion cannula have been positioned.

19. The device as set forth in claim 1, wherein:

a measuring means for measuring the concentration of said at least one constituent of said body fluid comprises a working electrode and a counter electrode; and

said working electrode is arranged in a section of said device which said body fluid flows through, wherein after positioning the device, said section extends outside said body tissue from said cannula up to and including said exposed surface of said capillary layer.