Multi-model blood pressure estimation

Patent metadata

Field	Value
Publication number	US-11844591-B2
Application number	US-201615268292-A
Country	US
Kind code	B2
Filing date	Sep 16, 2016
Priority date	Sep 16, 2016
Publication date	Dec 19, 2023
Grant date	Dec 19, 2023

Abstract

One aspect of the subject matter described in this disclosure can be implemented in a device capable of use in estimating blood pressure. The device includes one or more arterial sensors configured to obtain arterial measurements at two or more elevations. The device additionally includes one or more processors configured to determine one or more calibration parameters for a first blood pressure model based on the arterial measurements and a hydrostatic pressure difference between at least two of the elevations. The processors also are configured to determine a first blood pressure based on the first blood pressure model, the calibration parameters and the arterial measurements. The processors also are configured to determine a second blood pressure based in part on a second blood pressure model, one or more calibration parameters and the arterial measurements. The processors are further configured to provide a final blood pressure based on the first and second blood pressures.

First claim

What is claimed is:

1. A method for a biological sensor system, the method comprising:
obtaining, by one or more arterial sensors of the biological sensor system that are coupled with a subject, two or more arterial measurements of an artery of the subject, wherein each arterial measurement of the two or more arterial measurements comprises a respective arterial distension measurement and a respective mean arterial cross-sectional area measurement;
obtaining, by an elevation sensor of the biological sensor system, a respective elevation measurement corresponding to each arterial measurement of the two or more arterial measurements;
receiving, at a controller of the biological sensor system that is in communication with the one or more arterial sensors and with the elevation sensor, the two or more arterial measurements from the one or more arterial sensors and the respective elevation measurements from the elevation sensor;
determining, at the controller, a first calibration parameter and a second calibration parameter based on the two or more arterial measurements and a hydrostatic pressure difference between two elevations associated with two of the respective elevation measurements;
determining, at the controller, a first blood pressure in the artery based on a first blood pressure model, the first calibration parameter and the second calibration parameter, and the two or more arterial measurements;
calibrating, at the controller, a second blood pressure model based on the first blood pressure;
determining, at the controller, a second blood pressure in the artery based in part on the second blood pressure model, the first calibration parameter and the second calibration parameter, and the two or more arterial measurements; and
communicating, from the controller via one or more interfaces of the biological sensor system, a final blood pressure based on the first blood pressure and the second blood pressure.

2. The method of claim 1 , further including:
comparing, at the controller, the first blood pressure and the second blood pressure; and
updating, at the controller, the first calibration parameter and the second calibration parameter responsive to the comparison.

3. The method of claim 1 , wherein the determination of the first calibration parameter and the second calibration parameter includes:
determining, at the controller, a respective mean arterial distension for each of the two elevations; and
determining, at the controller, the first calibration parameter based on the respective mean arterial cross-sectional area measurements, the respective mean arterial distensions, and an arterial stress-strain relationship.

4. The method of claim 3 , wherein the determination of the first calibration parameter and the second calibration parameter further includes:
determining, at the controller, the second calibration parameter based on the hydrostatic pressure difference and the first calibration parameter.

5. The method of claim 1 , wherein the determination of the first blood pressure in the artery based on the first blood pressure model includes:
determining, at the controller, the first blood pressure further based on an arterial stress-strain relationship.

6. The method of claim 1 , wherein:
the two or more arterial measurements further include blood velocity measurements at each of the two elevations, and
the method further includes determining, at the controller, arterial blood flow measurements based on the respective mean arterial cross-sectional area measurements and the blood velocity measurements.

7. The method of claim 6 , wherein the determination of the first calibration parameter and the second calibration parameter includes:
determining, at the controller, the first calibration parameter and the second calibration parameter based on the hydrostatic pressure difference and the arterial blood flow measurements based on a linear relationship between blood pressure and blood flow.

8. The method of claim 7 , wherein the determination of the first blood pressure in the artery based on the first blood pressure model includes:
determining, at the controller, the first blood pressure based on the linear relationship and the arterial blood flow measurements.

9. The method of claim 1 , wherein the determination of the second blood pressure in the artery based in part on the second blood pressure model includes:
determining, at the controller, a pulse wave velocity (PWV) based on the two or more arterial measurements.

10. The method of claim 9 , wherein the determination of the PWV based on the two or more arterial measurements includes:
determining, at the controller, a pulse transit time (PTT) between two arterial locations based on the two or more arterial measurements; and
determining, at the controller, the PWV based on the PTT and a distance between the two arterial locations.

11. The method of claim 9 , wherein:
the two or more arterial measurements further include arterial cross-sectional area measurements and arterial blood velocity measurements,
the method further includes determining, at the controller, arterial blood flow measurements based on the arterial cross-sectional area measurements and the arterial blood velocity measurements, and
the determination of the PWV based on the two or more arterial measurements includes:
determining, at the controller, a derivative of the arterial blood flow measurements with respect to the arterial cross-sectional area measurements; and
determining, at the controller, the PWV based on the derivative.

12. A biological sensor system, comprising:
one or more arterial sensors operable to couple with a subject and to obtain arterial measurements of an artery of the subject, wherein the arterial measurements each comprise a respective arterial distension measurement and a respective mean arterial cross-sectional area measurement;
an elevation sensor operable to obtain elevation measurements corresponding to the arterial measurements of the artery of the subject;
one or more processors in communication with the one or more arterial sensors and the elevation sensor, the one or more processors configured to:
receive two or more arterial measurements from the one or more arterial sensors and a respective elevation measurement for each of the two or more arterial measurements from the elevation sensor;
determine a first calibration parameter and a second calibration parameter based on the two or more arterial measurements and a hydrostatic pressure difference between two elevations associated with two of the respective elevation measurements;
determine a first blood pressure in the artery based on a first blood pressure model, the first calibration parameter and the second calibration parameter, and the two or more arterial measurements;
calibrate a second blood pressure model based on the first blood pressure; and
determine a second blood pressure in the artery based in part on the second blood pressure model, the first calibration parameter and the second calibration parameter, and the two or more arterial measurements; and
an interface in communication with the one or more processors and configured to communicate a final blood pressure based on the first blood pressure and the second blood pressure.

13. The biological sensor system of claim 12 , wherein the one or more processors are further configured to:
compare the first blood pressure and the second blood pressure; and
update the first calibration parameter and the second calibration parameter responsive to the comparison.

14. The biological sensor system of claim 12 , wherein the d

Assignees

• Qualcomm Inc

Inventors

• Baek David Boettcher
• Lading Lars

Classifications

• A61B5/02125 Primary

  of pulse wave propagation time · CPC title

• A61B5/0059

  using light, e.g. diagnosis by transillumination, diascopy, fluorescence (photoacoustic A61B5/0093; optical measurement of heart rate A61B5/02416; optical measurement of blood flow A61B5/0261; optical measurement of analytes A61B5/1455) · CPC title

• A61B5/026

  Measuring blood flow {(A61B3/1233, A61B3/1241 take precedence)} · CPC title

• A61B5/02007

  Evaluating blood vessel condition, e.g. elasticity, compliance · CPC title

• A61B5/0261

  using optical means, e.g. infrared light · CPC title