PHYSIOLOGICAL ADAPTABILITY SYSTEM WITH MULTIPLE SENSORS

• US 20130310654A1
• Filed: 05/21/2012
• Published: 11/21/2013
• Est. Priority Date: 05/21/2012
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: CILIBRASI, Rudi, MARVIT, David L.
• Granted Patent: US 9,339,193 B2
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 5/4035 Evaluating the autonomic nervous system
• CPC Class Codes: A61B 5/72 Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: G16H 20/30 relating to physical therapies or activities, e.g. physiotherapy, acupressure or exercising
• CPC Class Codes: G16H 40/67 for remote operation

Abstract

According to an aspect of an embodiment, a method of measuring physiological adaptability of a subject is described. The method may include receiving, from a first sensor, a first data signal indicating a first biological function of the subject. The method may also include receiving, from a second sensor, a second data signal indicating a second biological function of the subject. The method may also include calculating an adaptability of the subject based on the first data signal and the second data signal. The method may also include reporting the calculated adaptability.

Claims

1. A method of measuring physiological adaptability of a subject, the method comprising:

receiving, from a first sensor, a first data signal indicating a first biological function of the subject;

receiving, from a second sensor, a second data signal indicating a second biological function of the subject;

calculating an adaptability of the subject based on the first data signal and the second data signal; and

reporting the calculated adaptability.

2. The method of claim 1, wherein each of the first and second biological functions vary over time, a variability of the second biological function depending on a variability of the first biological function.

3. The method of claim 1, wherein the first and second data signals are received while the subject is moving in an uncontrolled environment.

4. The method of claim 1, wherein:

the first biological function includes one of;

a respiratory function, a dermal function, or a motor function; and

the second biological function includes one of;

a cardiac function, a respiratory function, or a biochemical function.

5. The method of claim 1, wherein the first biological function includes a respiratory function, the second biological function includes a cardiac function, and the adaptability of the subject includes a stress adaptability of the subject.

6. The method of claim 5, further comprising detecting a sequence of heart beats in the second data signal, each sequential pair of detected heart beats defining a start time and an end time of an associated time interval, wherein the calculating a stress adaptability of the subject based on the first data signal and the second data signal comprises:

determining time intervals when the subject is generally inhaling and time intervals when the subject is generally exhaling;

determining a first average heart rate corresponding to time intervals when the subject is generally inhaling;

determining a second average heart rate corresponding to time intervals when the subject is generally exhaling; and

calculating a difference between the first average heart rate and the second average heart rate.

7. The method of claim 6, wherein determining time intervals when the subject is generally inhaling and time intervals when the subject is generally exhaling includes, for each time interval:

determining a difference between a first instantaneous measurement of the respiratory function and a second instantaneous measurement of the respiratory function, the first instantaneous measurement corresponding to the start time and the second instantaneous measurement corresponding to the end time of the corresponding time interval;

dividing the difference by a threshold value;

when the difference divided by the threshold value is greater than or equal to one, determining that the subject is inhaling during the corresponding time interval;

when the difference divided by the threshold value is less than or equal to negative one, determining that the subject is exhaling during the corresponding time interval; and

when the difference divided by the threshold value is between negative one and one, determining that the corresponding time interval is a split time interval including a first portion and a second portion and that the subject is inhaling during the first portion and exhaling during the second portion.

8. The method of claim 7, wherein;

the threshold value is based on a difference between a maximum instantaneous measurement of the respiratory function and a minimum instantaneous measurement of the respiratory function during a temporal window having a predetermined length;

determining a first average heart rate corresponding to time intervals when the subject is generally inhaling includes;

in a first beat accumulator, accumulating one heart beat for each time interval during which the subject is determined to be inhaling;

in a first time accumulator, accumulating each time interval during which the subject is determined to be inhaling;

for each split time interval and corresponding heart beat;

in the first time accumulator, accumulating a first fraction of the split time interval corresponding to the first portion of the split time interval; and

in the first beat accumulator, accumulating a same first fraction of the corresponding heart beat; and

dividing a sum of accumulated heart beats from the first beat accumulator by a corresponding sum of accumulated time intervals from the first time accumulator; and

determining a second average heart rate corresponding to time intervals when the subject is generally exhaling includes;

in a second beat accumulator, accumulating one heart beat for each time interval during which the subject is determined to be exhaling;

in a second time accumulator, accumulating each time interval during which the subject is determined to be exhaling;

for each split time interval and corresponding heart beat;

in the second time accumulator, accumulating a second fraction of the split time interval corresponding to the second portion of the split time interval; and

in the second beat accumulator, accumulating a same second fraction of the corresponding heart beat; and

dividing a sum of accumulated heart beats from the second beat accumulator by a corresponding sum of accumulated time intervals from the second time accumulator.

9. The method of claim 6, wherein:

each sequential pair of detected heart beats includes a first heart beat detected at a corresponding start time and a second heart beat detected at a corresponding end time of the associated time interval;

the first heart beat of a given time interval corresponds to the second heart beat of an immediately preceding time interval; and

detecting a sequence of heart beats in the second data signal includes;

calculating a duration of each of the associated time intervals;

comparing a duration of each time interval to a duration of an immediately preceding time interval; and

when the duration of the given time interval is less than a predetermined fraction of the duration of the immediately preceding time interval, discarding the second heart beat of the given time interval and pairing the first heart beat with a next heart beat in the sequence of detected heart beats.

10. A system for measuring physiological adaptability of a subject, the system comprising:

a first sensor configured to generate a first data signal indicating a first function of the subject;

a second sensor configured to generate a second data signal indicating a second biological function of the subject; and

a computing device communicatively coupled to the first sensor and the second sensor, the computing device configured to;

receive the first data signal and the second data signal;

calculate an adaptability of the subject based on the first data signal and the second data signal; and

report the calculated adaptability to a user via an output device.

11. The system of claim 10, wherein the first sensor comprises a respiratory inductance plethysmograph (RIP), a blood oxygen level sensor, or a breath sensor.

12. The system of claim 10, wherein the second sensor comprises a heart rate monitor, an electrocardiography (ECG) device, or a Holter monitor.

13. The system of claim 10, further comprising a battery configured to power the system such that the system is mobile.

14. The system of claim 10, wherein the first sensor comprises a respiratory sensor, the second sensor comprises a cardiac sensor, and the computing device comprises:

a sensor hub communicatively coupled to the respiratory sensor and the cardiac sensor;

a respiratory module communicatively coupled to the sensor hub;

a cardiac module communicatively coupled to the sensor hub and to the respiratory module;

a stress adaptability analysis engine communicatively coupled to the cardiac module; and

the output device communicatively coupled to the stress adaptability analysis engine.

15. The system of claim 14, wherein:

the sensor hub is configured to receive and temporally synchronize the first data signal and the second data signal;

the respiratory module is configured to determine time intervals when the subject is generally inhaling and time intervals when the subject is generally exhaling, the respiratory module including;

a smoothing filter;

a numerical differentiator communicatively coupled to the digital smoothing filter;

a clamp coupled to the numerical differentiator; and

a breathing classifier communicatively coupled to the clamp;

the cardiac module is configured to collect heart beat and time interval data associated with time intervals when the subject is generally inhaling and time intervals when the subject is generally exhaling, the cardiac module including;

a heart beat detector;

a heart beat interval timer communicatively coupled to the heart beat detector;

a distributor communicatively coupled to the heart beat detector and the heart beat interval timer;

an inhale accumulator pair communicatively coupled to the distributor; and

an exhale accumulator pair communicatively coupled to the distributor;

the stress adaptability analysis engine is configured to;

determine a first average heart rate corresponding to time intervals when the subject is generally inhaling;

determine a second average heart rate corresponding to time intervals when the subject is generally exhaling; and

calculate a difference between the first average heart rate and the second average heart rate as the calculated stress adaptability; and

the output device comprises a display device.

16. A processor configured to execute computer instructions to cause a computing system to perform operations for measuring physiological adaptability of a subject, the operations comprising:

receiving, from a first sensor, a first data signal indicating a first biological function of the subject;

receiving, from a second sensor, a second data signal indicating a second biological function of the subject;

calculating an adaptability of the subject based on the first data signal and the second data signal; and

reporting the calculated adaptability.

17. The processor of claim 16, wherein the calculated adaptability of the subject comprises a calculated respiratory sinus arrhythmia (RSA) of the subject.

18. The processor of claim 16, wherein the calculated adaptability comprises a constant number.

19. The processor of claim 16, wherein the calculating an adaptability of the subject based on the first data signal and the second data signal includes extracting spectral characteristics from each of the first data signal and the second data signal and combining the spectral characteristics to determine the adaptability.

20. The processor of claim 16, wherein the operations further include:

temporally synchronizing the first data signal and the second data signal; and

digitally filtering the first data signal to smooth the first data signal.