Internal jugular and left ventricular thermodilution catheter

• US 4,217,910 A
• Filed: 10/10/1978
• Issued: 08/19/1980
• Est. Priority Date: 10/10/1978
• Status: Expired due to Term

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Khalil, Hassan H.
• Primary Examiner(s): Howell, Kyle L.
• Application Number:
  US05/949,912
• Time in Patent Office: 679 Days
• Field of Search: 128/670, 128/692, 128/713, 128/642, 73/204
• US Class Current: 600/483
• CPC Class Codes: A61B 5/028 by thermo-dilution
• CPC Class Codes: A61B 5/283 Invasive

Abstract

A thermodilution catheter having a distal high frequency heating coil of fine wires, heat measuring thermocouples, and a proximal resistance thermometer, all wound externally on a catheter for measuring blood flow in either the jugular vein or the left ventricle of the heart. The device also incorporates electrodes for electrocardiogram tracings.

Claims

1. A bioelectric measuring apparatus for insertion within a living organism comprising:

an elongated, flexible, catheter body having a distal or tip end and a proximal segment;

main heating means, mounted on the distal or top end of said catheter body, for tepefying the surrounding substance of said living organism;

temperature measuring means, mounted on the proximal segment of said catheter body, for quantifying the amount of caloric energy conducted to the surrounding substance of said living organism; and

auxiliary heating means, electrically connected to said main heating means by lead wires, for providing heat to said lead wires.

2. A bioelectric measuring apparatus for insertion with a living organism according to claim 1 wherein said main heating means is a bifiliary wound heating coil.

3. A bioelectric measuring apparatus for insertion within a living organism according to claim 1 wherein said temperature measuring means comprises a platinum resistance thermometer.

4. A bioelectric measuring apparatus for insertion within a living organism according to claim 1 wherein said auxillary heating means comprises;

a heating coil detached from said body for heating said lead wires; and

switching means, electrically connected to said main heating means and said heating coil for selectively supplying current to either said main heating means or said heating coil.

6. A bioelectric measuring apparatus for insertion within a living organism according to claim 4 wherein said switching means comprises a double pole double throw switch.

7. A bioelectric measuring apparatus for insertion within a living organism according to claim 1 further comprising

conducting means, mounted on said body, for electrical contact with said living organism;

and

temperature transducing means mounted on said body, for sensing the temperature of said body produced by said main heating means.

8. A bioelectric measuring apparatus for insertion within a living organism according to claim 7 wherein said conducting means comprises one or more electrodes.

9. A bioelectric measuring apparatus for insertion within a living organism according to claim 8 wherein said electrodes comprise bare platinum electrodes.

10. A bioelectric measuring apparatus for insertion within a living organism according to claim 7 wherein said temperature transducing means comprises;

a thermocouple positioned along said main heating means; and

a reference thermocouple positioned proximally to said main heating means.

11. A bioelectric measuring apparatus for insertion within a living organism according to claim 10 wherein said thermocouples are copper constantan thermocouples.

5. A bioelectric measuring apparatus for insertion within a living organism according to claim 5 wherein said heating coil comprises a bifilarlywound coil with an impedance identical to that of said main heating means.