INTRODUCER SHEATH WITH ELECTRODES

• US 20100174170A1
• Filed: 10/16/2009
• Published: 07/08/2010
• Est. Priority Date: 01/05/2009
• Status: Active Grant

• Current Assignee: Texas Heart Institute
• Original Assignee: Texas Heart Institute
• Inventors: RAZAVI, Mehdi
• Granted Patent: US 8,366,615 B2
• Time in Patent Office: Days
• US Class Current: 600/371
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61M 25/0662 Guide tubes

Abstract

An apparatus comprises a sheath for introducing a catheter into a blood vessel, at least one electrode provided on the sheath, at least one other electrode; and a measuring device to which at least one pair of electrodes are coupled. The measuring device measures the impedance or conduction velocity between the first electrode on the sheath and the second electrode.

Claims

1. An apparatus, comprising:

a sheath for introducing a catheter into a blood vessel; and

a plurality of electrodes provided on said sheath.

2. The apparatus of claim 1 wherein said sheath comprises a tubular member and at least one of the said electrodes is provided on an outer surface of said tubular member.

3. The apparatus of claim 1 wherein said sheath comprises a tubular member and at least one of the said electrodes is provided on an inner surface of said tubular member.

4. The apparatus of claim 1 wherein at least one of the said electrodes is embedded within material defining said sheath.

5. The apparatus of claim 1 wherein said electrodes include at least one electrode that is a ring electrode.

6. The apparatus of claim 1 wherein said electrodes include at least one electrode that is a partial ring electrode.

7. The apparatus of claim 1 further comprising conductive wires, one end of each which connects to one of the said electrodes, and at least some of said wires extending along said sheath.

8. The apparatus of claim 1 further comprising conductive wires, one end of each wire connecting to one of the said electrodes, and at least some of said wires extending within said sheath.

9. The apparatus of claim 1 further comprising a dilator insertable into said sheath.

10. The apparatus of claim 1 further comprising at least one non-sheath electrode electrically coupled, through living tissue, to the electrode provided on the sheath, for determining electrical impedance.

11. The apparatus of claim 10 wherein said non-sheath second electrode is a skin electrode or an electrode on a urinary catheter.

12. An apparatus, comprising:

a sheath for introducing a catheter into a blood vessel;

a plurality of electrodes provided on said sheath;

one or more non-sheath electrodes; and

a measuring device to which the sheath and non-sheath electrodes are coupled, said measuring device measuring the impedance or conduction velocity between the first electrode on the sheath and the second electrode.

13. The apparatus of claim 12 further comprising one or more electrical conductors extending along at least part of the sheath with the separate conductors corresponding to the separate sheath electrodes, and with at least one conductor connecting to the measuring device to conduct a signal between at least one sheath electrode and the impedance measuring device.

14. A method for detecting bleeding in a person, comprising;

inserting a sheath into a blood vessel, said sheath including a plurality of electrodes;

injecting, by a current source, an electrical current that runs through at least one of said electrodes;

computing, by logic, an impedance or conduction velocity based on said injected current; and

determining, by said logic, whether said impedance or conduction velocity is at a level indicative of bleeding or a clot.

15. The method of claim 14 wherein inserting said sheath comprises inserting said sheath into a femoral artery or other vessel.

16. The method of claim 14 further comprising placing at least one non-sheath electrode on the skin of the person and wherein computing the impedance comprises computing the impedance between at least one electrode on the skin and at least one sheath electrode.

17. The method of claim 14 wherein computing the impedance comprises computing an impedance amplitude value and an impedance phase value.

18. The method of claim 14 further comprising performing a calibration mode in which an impedance threshold is computed.

19. The method of claim 14 further comprising computing an impedance following completion of a medical procedure for which the sheath was inserted.