Polarographic catheter probe

• US 4,413,627 A
• Filed: 10/03/1980
• Issued: 11/08/1983
• Est. Priority Date: 10/27/1979
• Status: Expired due to Term

• Current Assignee: Dr Eduard Fresenius Chemisch-Pharmazeutische Industrie KG Apparatebau KG
• Original Assignee: Dr Eduard Fresenius Chemisch-Pharmazeutische Industrie KG Apparatebau KG
• Inventors: Schindler, Johannes G.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US06/193,599
• Time in Patent Office: 1,131 Days
• Field of Search: 128/635, 204/195 B, 204/195 P, 204/195 G
• US Class Current: 600/348
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: G01N 27/48 using polarography, i.e. measuring changes in current under a slowly-varying voltage

Abstract

A polarographic catheter-shaped probe for determining analytical data of logical fluids of human beings, of animals, or of plants, and having a cathode, an anode and an electrolyte connecting the two, which are surrounded by a flexible sheath sealed in the tip region of the cathode by an ion-impermeable but gas-permeable membrane, wherein the anode is arranged at the distal end of the catheter shaft away from the cathode tip, the electrolyte extends from the anode to the tip of the cathode within the probe, and the anode and cathode are connected to a terminal jack for measuring instruments located at the end of the probe facing the anode. The jack optionally contains a supply chamber for the electrolyte, which is connected in a liquid-tight manner to the one end of the catheter shaft.

Claims

1. A polarographic catheter-shaped probe for intravenously determining data of fluids, comprising:

a cathode;

an anode;

an electrolyte disposed between said anode and said cathode;

a longitudinally extending flexible catheter sheath having opposed ends, said cathode disposed at one end of said sheath to define a cathode tip, said flexible sheath concentrically surrounding said cathode and said electrolyte and provided with an ion-impermeable but gas-permeable membrane at said cathode tip to seal said electrolyte between said flexible sheath and said cathode, said sheath defining a distal end opposite said cathode tip;

said anode disposed adjacent said distal end of said catheter sheath with the electrolyte extending from said cathode tip to said distal end between said sheath and said cathode; and

a terminal jack located adjacent the distal end of said sheath and electrically coupled to said anode and cathode, said jack adapted for connecting said anode and cathode to measuring instruments.

2. A probe according to claim 1 wherein said jack comprises:

a reservoir chamber containing a supply of said electrolyte, said chamber communicating in a liquid-tight manner with electrolyte in the distal end of said catheter sheath.

3. A probe according to claim 2 further comprising:

an insulating jacket concentrically surrounding said cathode, said cathode having a free end plane abutting said membrane.

4. A probe according to claim 3, wherein said insulating jacket comprises:

a glass coating formed concentrically on a portion of said cathode adjacent said membrane, and

a flexible insulating covering surrounding the remaining portion of said cathode.

5. A probe according to claim 3, further comprising:

said electrolyte concentrically surrounding the insulated cathode and reaching from the electrolyte reservoir chamber provided in the terminal jack up to the free end plane of said cathode insulating jacket.

6. A probe according to claim 2, further comprising:

a fiber strand or a capillary system extending between the electrolyte reservoir chamber and the cathode tip for producing an electrolytic connection between the cathode tip and the anode as a result of capillary action.

7. A probe according to claim 8, further comprising:

said fiber strand or said capillary system concentrically surrounding the cathode.

8. A probe according to claim 3, further comprising:

said insulating jacket coated with a sponge- or gel-like substance reaching from the anode up to the cathode free end plane, in which substance said electrolyte is embedded.

9. A probe according to claim 8, further comprising:

agar-agar selected as the gel-like substance, into which a salt is embedded as electrolyte.

10. A probe according to claim 9, wherein said electrolyte salt comprises:

potassium chloride.

11. A probe according to claim 9 wherein said electrolyte salt comprises:

sodium chloride.

12. A probe according to claim 1, further comprising:

an insulating coating concentrically surrounding said cathode.

13. A probe according to claim 12, wherein said insulating coating comprises:

polytetrafluoroethylene.