Blood pressure determination based on delay times between points on a heartbeat pulse

• US 20050096551A1
• Filed: 01/29/2003
• Published: 05/05/2005
• Est. Priority Date: 01/29/2002
• Status: Active Grant

• Current Assignee: Empirical Technologies Corporation
• Original Assignee: Empirical Technologies Corporation
• Inventors: Baruch, Martin C.
• Granted Patent: US 7,087,025 B2
• Time in Patent Office: Days
• US Class Current: 600/485
• CPC Class Codes: A61B 5/02125 of pulse wave propagation time
• CPC Class Codes: A61B 5/7257 using Fourier transforms

Abstract

Blood pressure determination with resolution sufficient to resolve Pulsus Paradoxus is based on measurement of delay time between points on a heartbeat pulse.

Claims

1. A method of monitoring blood pressure, which comprises:

determining delay time between predetermined points on the front side or between predetermined points on the back side of a heartbeat pulse, and

using the delay time to obtain a measurement of blood pressure.

4. A method according to claim 1 or claim 3, wherein the heartbeat pulse is detected by a sensor at a site on a body through which blood flows.

5. A method according to claim 4, wherein the sensor responds to blood pressure changes.

6. A method according to claim 4, wherein the sensor responds to blood vessel displacement.

20. A process of determining changes in blood pressure, which comprises:

repeating the method of any one of claims 1, 3, and 7-10 for each of a series of heartbeat pulses over a period of time; and

producing an output of blood pressure measurement over the period of time.

21. A process according to claim 20, wherein peak-to-peak variations of the blood pressure output are used to determine Pulsus Paradoxus.

22. A process according to claim 20, wherein the output is filtered to isolate Pulsus Paradoxus modulations.

37. A process of determining changes in blood pressure, which comprises:

repeating the method of claim 4 for each of a series of heartbeat pulses over a period of time; and

producing an output of blood pressure measurement over the period of time.

38. A process according to claim 37, wherein peak-to-peak variations of the blood pressure output are used to determine Pulsus Paradoxus.

39. A process according to claim 37, wherein the output is filtered to isolate Pulsus Paradoxus modulations.

2. (canceled)

3. A method of monitoring blood pressure, which comprises:

determining delay time between predetermined points on the front side or between predetermined points on the back side of a heartbeat pulse, and

using the delay time to obtain a measurement of blood pressure,

wherein the predetermined points are set at predetermined percentages of the peak amplitude of the heartbeat pulse.

7. A method of monitoring blood pressure, which comprises:

determining delay time between predetermined points on a heartbeat pulse, and

using the delay time to obtain a measurement of blood pressure,

wherein the predetermined points on the heartbeat pulse are on an onset slope of the pulse.

8. A method according to claim 7, wherein plural delay times are measured between predetermined points on the onset slope that are located on a portion of the onset slope that extends between the peak of the pulse and 50% of the peak of the pulse.

9. A method according to claim 8, wherein the plural delay times are averaged.

10. A method of monitoring blood pressure, which comprises:

determining delay time between predetermined points on a heartbeat pulse, and

using the delay time to obtain a measurement of blood pressure,

wherein the predetermined points on the heartbeat pulse are on a back-end slope of the pulse.

11. Apparatus for monitoring blood pressure, comprising:

a sensor that detects a heartbeat pulse at a site on a body through which blood flows, and

a unit that determines delay time between predetermined points on the front side or between predetermined points on the back side of the detected heartbeat pulse and that uses the delay time to obtain a measurement of blood pressure.

18. Apparatus according to any one of claims 11 and 13-17, wherein the sensor responds to changes in blood pressure.

19. Apparatus according to any one of claims 11 and 13-17, wherein the sensor responds to blood vessel displacement.

23. Apparatus according to any one of claims 11 and 13-17, wherein the sensor detects a series of heartbeat pulses over a period of time, and the unit determines delay times between predetermined points on each of the detected heartbeat pulses and uses the determined delay times to provide an output of blood pressure measurement over the period of time.

24. Apparatus according to claim 23, wherein the unit performs peak-to-peak measurement of blood pressure variations in the output to determine Pulsus Paradoxus.

25. Apparatus according to claim 23, wherein the output is filtered to isolate Pulsus Paradoxus modulations.

12. (canceled)

13. Apparatus for monitoring blood pressure, comprising:

a sensor that detects a heartbeat pulse at a site on a body through which blood flows, and

a unit that determines delay time between predetermined points on the front side or between predetermined points on the back side of the detected heartbeat pulse and that uses the delay time to obtain a measurement of blood pressure,

wherein the predetermined points are set at predetermined percentages of the peak amplitude of the heartbeat pulse.

14. Apparatus for monitoring blood pressure, comprising:

a sensor that detects a heartbeat pulse at a site on a body through which blood flows, and

a unit that determines delay time between predetermined points on the detected heartbeat pulse and that uses the delay time to obtain a measurement of blood pressure,

wherein the predetermined points on the heartbeat pulse are on an onset slope of the pulse.

15. Apparatus for monitoring blood pressure, comprising:

a sensor that detects a heartbeat pulse at a site on a body through which blood flows, and

a unit that determines delay time between predetermined points on the front side or between predetermined points on the back side of the detected heartbeat pulse and that uses the delay time to obtain a measurement of blood pressure,

wherein the unit measures plural delay times between the predetermined points on the heartbeat pulse.

16. Apparatus according to claim 15, wherein the plural delay times are averaged.

17. Apparatus for monitoring blood pressure, comprising:

a sensor that detects a heartbeat pulse at a site on a body through which blood flows, and

a unit that determines delay time between predetermined points on the detected heartbeat pulse and that uses the delay time to obtain a measurement of blood pressure,

wherein the predetermined points on the heartbeat pulse are on a back-end slope of the pulse.

26. A method of measuring blood pressure based on analysis of a single heartbeat pulse at a single site.

28. A method according to claim 26 or claim 27 in which the method is non-occlusive.

27. A method of measuring blood pressure based on measurement of a parameter of a single heartbeat pulse at a single site.

29. An apparatus that measures blood pressure by analysis of a single heartbeat pulse at a single site.

31. An apparatus according to claim 29 or claim 30 in which the apparatus is non-occlusive.

30. An apparatus that measures blood pressure based on measurement of a parameter of a single heartbeat pulse at a single site.

32. A method of monitoring blood pressure, which comprises:

determining plural delay times between predetermined points on the front side or between predetermined points on the back side of a heartbeat pulse, and

using the plural delay times to obtain a measurement of blood pressure.

33. A method according to claim 32, wherein the plural delay times are averaged.

34. A process of determining changes in blood pressure, which comprises:

repeating the method of claim 32 or claim 33 for each of a series of heartbeat pulses over a period of time; and

producing an output of blood pressure measurement over the period of time.

35. A process according to claim 34, wherein variations of the blood pressure output are used to determined Pulsus Paradoxus.

36. A process according to claim 35, wherein the output is filtered to isolate Pulsus Paradoxus modulations.