Blood pressure estimating apparatus and method

• US 10,045,700 B2
• Filed: 01/27/2016
• Issued: 08/14/2018
• Est. Priority Date: 08/11/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Noh, Seungwoo, Jung, Taesung, Kim, Younho, Park, Sangyun
• Primary Examiner(s): Natnithithadha, Navin
• Application Number:
  US15/007,625
• Publication Number:
  US 20170042433A1
• Time in Patent Office: 930 Days
• Field of Search: 600485, 600486, 600488, 600500-503, 600481, 600483, 600484
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/02108 from analysis of pulse wave characteristics
• CPC Class Codes: A61B 5/02225 using the oscillometric method
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/1102 Ballistocardiography
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence

Abstract

A blood pressure estimating method includes measuring a biosignal including pulse wave information of a user, determining a calibration method for a blood pressure estimation model, calibrating the blood pressure estimation model using the determined calibration method, and estimating a blood pressure of the user from the biosignal using the calibrated blood pressure estimation model.

Claims

1. A blood pressure estimating apparatus, comprising:

a first sensor configured to measure a first biosignal comprising pulse wave information of a user;

a second sensor configured to measure a second biosignal;

a calibration controller configured to determine a calibration time at which a calibration is to be performed on a blood pressure estimation model and a calibration method for the blood pressure estimation model, the determined calibration method being selected between a first calibration method for calibrating the blood pressure estimation model based a measured blood pressure value and a second calibration method for calibrating the blood pressure estimating model based on the second biosignal, the second calibration method taking less time than the first calibration method;

a calibrator configured to calibrate the blood pressure estimation model at the determined calibration time using the determined calibration method; and

a blood pressure estimator configured to estimate a blood pressure of the user from the first biosignal using the calibrated blood pressure estimation model.

2. The apparatus of claim 1, wherein the calibration controller is further configured to determine the calibration time and

select the first calibration method for calibrating the blood pressure estimating model when the signal quality of the first biosignal is less than or equal to a threshold and/or a threshold elapsed time since a previous calibration of the blood pressure estimation model was performed has been reached;

and

select the second calibration method when the first calibration is not selected.

3. The apparatus of claim 1, wherein the calibration controller is further configured to:

determine the calibration time and the calibration method based on any one or any combination of any two or more of movement information of the user, external temperature information, and body temperature information of the user; and

control an operation of the first sensor.

4. The apparatus of claim 1, wherein the first calibration method of calibrating the blood pressure estimation model based on a blood pressure value measured using a cuff.

5. A blood pressure estimating apparatus, comprising:

a first sensor configured to sense a first biosignal of a user;

a blood pressure estimator configured to estimate a blood pressure of the user from the first biosignal using a blood pressure estimation model;

a calibrator configured to calibrate the blood pressure estimation model using a plurality of calibration methods;

a calibration controller configured to select one of the calibration methods, and control the calibrator to calibrate the blood pressure estimation model using the selected calibration method; and

a second sensor configured to sense a second biosignal of the user;

wherein the plurality of calibration methods comprise;

a first calibration method in which the calibrator calibrates the blood pressure estimation model based on a blood pressure of the user measured using a cuff; and

a second calibration method in which the calibrator calibrates the blood pressure estimation model based on the first biosignal and the second biosignal, and takes less time than the first calibration method.

6. The apparatus of claim 5, wherein the calibration controller is further configured to alternately select the first calibration method and the second calibration method.

7. The apparatus of claim 5, wherein the calibration controller is further configured to:

determine a signal quality of the first biosignal,

select the first calibration method in response to either the signal quality of the first biosignal being less than or equal to a predetermined threshold or a predetermined amount of time elapsing since a last calibration of the blood pressure estimation model was performed, and

select the second calibration method in response to the first calibration method not being selected.

8. The apparatus of claim 5, further comprising:

at least one additional first sensor configured to sense a first biosignal of the user so that the apparatus comprises a plurality of first sensors configured to sense a plurality of first biosignals of the user at a plurality of different sensing locations on the user; and

a signal selector configured determine respective signal qualities of the first biosignals, select one of the first biosignals having a highest signal quality, and output the selected first biosignal to the blood pressure estimator.

9. A blood pressure estimating method, comprising:

measuring a first biosignal comprising pulse wave information of a user;

measuring a second biosignal;

determining a signal quality of the first biosignal;

determining a calibration method for a blood pressure estimation model, the determined calibration method being selected between a first calibration method for calibration the blood pressure estimation model based a measured blood pressure value and a second calibration method for calibrating the blood pressure estimation model based on the second biosignal, the second calibration method taking less time than the first calibration method;

calibrating the blood pressure estimation model using the determined calibration method; and

estimating a blood pressure of the user from the first biosignal using the calibrated blood pressure estimation model.

10. The method of claim 9, wherein:

the determining of the calibration method comprises;

selecting the first calibration method for calibrating the blood pressure estimation model when the signal quality of the first biosignal is less than or equal to a threshold and/or a threshold elapsed time since a previous calibration of the blood pressure estimation model was performed has been reached; and

selecting the second calibration method when the first calibration is not selected.

11. The method of claim 9, wherein the determining of the calibration method comprises determining the calibration method for the blood pressure estimation model based on any one or any combination of any two or more of movement information of the user, external temperature information, and body temperature information of the user.

12. The method of claim 9, wherein the first calibration method of calibrating the blood pressure estimation model is based on a blood pressure value measured using a cuff.

13. The method of claim 12, wherein the determining of the calibration method comprises determining that the second calibration method is to be performed between points in time at which the first calibration method is performed.

14. The method of claim 12, wherein the first biosignal is a photoplethysmogram (PPG) signal;

and the second biosignal is an electrocardiogram (ECG) signal or a biosignal comprising blood oxygen saturation (SpO₂) information.

15. The method of claim 9,

wherein the determining of the calibration method is performed in response to a result of determining whether to calibrate the blood pressure estimation model.

16. The method of claim 15, wherein the determining of whether to calibrate the blood pressure estimation model comprises determining whether to calibrate the blood pressure estimation model based on either one or both of a signal quality of the first biosignal and an elapsed time since a previous calibration of the blood pressure estimation model was performed.

17. The method of claim 15, wherein the determining of whether to calibrate the blood pressure estimation model comprises determining whether to calibrate the blood pressure estimation model based on any one or any combination of any two or more of movement information of the user, external temperature information, and body temperature information of the user.

18. The method of claim 9, wherein the measuring of the first biosignal comprises:

measuring first biosignals of a same type; and

selecting a reference biosignal from the first biosignals based on signal qualities of the first biosignals; and

the estimating of the blood pressure of the user comprises estimating the blood pressure of the user from the reference biosignal using the calibrated blood pressure estimation model.

19. A non-transitory computer-readable storage medium storing instructions to cause computing hardware to perform the method of claim 9.