METHOD AND DEVICE FOR THE NON-INVASIVE DETECTION OF BLOOD FLOW AND ASSOCIATED PARAMETERS IN PARTICULAR ARTERIAL WAVEFORM AND BLOOD PRESSURE

• US 20090275845A1
• Filed: 12/15/2005
• Published: 11/05/2009
• Est. Priority Date: 12/20/2004
• Status: Abandoned Application

• Current Assignee: Kaz USA Incorporated (Helen of Troy Limited)
• Original Assignee: Kaz USA Incorporated (Helen of Troy Limited)
• Inventors: Schnak, Fred, Kressmann, Frank, Freund, Dirk, Giersiepen, Martin, Harttmann, Brigitte, Roenneberg, Gerrit, Hollinger, Stefan, Wunder, Dieter, Heck, Ulrich
• Application Number:
  US11/722,344
• Publication Number:
  US 20090275845A1
• Time in Patent Office: Days
• US Class Current: 600/504
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence

Abstract

A method and a device for the non-invasive determination of blood flow and associated parameters in arteries, in particular the arterial waveform and the blood pressure. According to said method, a sensor having at least one deformable contact portion is placed on a tissue surface, essentially over an artery, and the contact portion is subjected to a temporally variable and defined external force, F(t). The deformation of the contact portion by the blood flow inside the artery in response to said force F(t) is measured.

Claims

1. A method for the non-invasive determination of blood flow and associated parameters in arteries comprising:

placing a sensor including at least one deformable contact portion on a tissue surface, the at least one contact portion being subjected to a temporally variable and defined external force, F(t);

wherein deformation of the at least one contact portion resulting from blood flow in the artery as a reaction to the application of the force F(t) is measured; and

wherein the force F(t) is generated by pressure increase inside the sensor itself.

2. A method according to claim 1 wherein the deformation of a plurality of contact portions arranged in the form of an array is measured.

3. A method according to claim 1 wherein the force F(t) is applied manually, to the at least one contact portion.

4. A method according to claim 1 wherein the force F(t) is applied to the contact portion by an electrical motor or pneumatic device.

5. A method according to claim 1 wherein the force F(t) is increased at a constant rate over time in the form of a linear ramp function R(t)=λ

t.

6. A method according to claim 1 wherein the deformation of the at least one contact portion is measurable via the curvature ε

(t) of the contact portion.

7. A method according to claim 1 wherein the determination is carried out at an upper arm, wrist, temporal region, ankle, or finger of a user.

8. A device for the non-invasive determination of blood flow and associated parameters in arteries comprising:

a sensor having at least one deformable contact portion operable to be subjected to a temporally variable and defined external force, F(t);

wherein the sensor has a measuring device operable to determine deformation of the at least one contact portion via the blood flow in the artery as a reaction to the application of the force F(t); and

wherein the sensor is in the form of a single-chamber sensor; and

wherein the forcing organ is in the form of a pneumatic unit.

9. A device according to claim 8 wherein the sensor has a chamber filled with a fluid the chamber having generally rigid non-deformable walls and the at least one contact portion which is deformable.

10. A device according to claim 8, wherein the at least one deformable contact portion is in the form of a membrane.

11. A device according to claim 8, wherein a plurality of contact portions arranged in the form of an array or matrix are provided, and a separate measuring device is provided for each such contact portion.

12. A device according to claim 8, wherein the measuring device comprises a strain-measuring strip.

13. A device according to claim 8, wherein a forcing organ is provided to exert the force.

14. A device according to claim 13, wherein the forcing organ has means for measuring the force F(t).

15. A device according to claim 13, wherein a separate force-measuring device is provided.

16. A device according to claim 8, wherein the pneumatic unit comprises a fluid pump.

17. A device according to claim 12, wherein the measuring device is in the form of a pressure-measuring device for measuring the fluid pressure inside the chamber.

18. A device according to claim 8, wherein the force F(t) is increased at a constant rate over time, in the form of a linear ramp function R(t)=λ

t.

19. A device according to claim 8, further comprising a holding element, by which the device is fixable to a wrist, upper arm, temple area, ankle, or finger, of a user.