System method and device for determining the risk of dehydration

• US 9,220,444 B2
• Filed: 06/06/2011
• Issued: 12/29/2015
• Est. Priority Date: 06/07/2010
• Status: Active Grant

• Current Assignee: Zephyr Technology Corporation (Medtronic Plc)
• Original Assignee: Zephyr Technology Corporation (Medtronic Plc)
• Inventors: Russell, Brian
• Primary Examiner(s): Thomson, William
• Assistant Examiner(s): Archer, Marie
• Application Number:
  US13/154,317
• Publication Number:
  US 20120143019A1
• Time in Patent Office: 1,667 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2560/0242 adapted to measure environmental factors, e.g. temperature, pollution
• CPC Class Codes: A61B 2560/0475 Special features of memory means, e.g. removable memory cards
• 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 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/14507 specially adapted for measuring characteristics of body fluids other than blood devices for taking samples of body liquids A61B10/0045
• CPC Class Codes: A61B 5/165 Evaluating the state of mind, e.g. depression, anxiety
• CPC Class Codes: A61B 5/4266 sweat secretion
• CPC Class Codes: A61B 5/4875 Hydration status, fluid retention of the body
• CPC Class Codes: A61B 5/6823 Trunk, e.g., chest, back, abdomen, hip
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• 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: A61B 5/7271 Specific aspects of physiological measurement analysis A61B5/316, A61B5/349 and A61B5/374 take precedence
• CPC Class Codes: A61B 5/7405 using sound
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick
• CPC Class Codes: G16H 40/67 for remote operation
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/30 : for calculating health indices; for individual health risk assessment

Abstract

A system, device and method of determining the probability of dehydration of a person is provided. In one embodiment, the method comprises receiving data of a heart rate of the person; receiving data of a posture of the person; determining that a first posture of the person satisfies first posture criteria for a first predetermined time period; determining a first heart rate for the person during the first predetermined time period; subsequent to determining that the first posture of the person satisfies first posture criteria for a first predetermined time period, determining that a second posture of the person satisfies second posture criteria for at least a second predetermined period; determining a second heart rate for the person during the second predetermined time period; determining a change in heart rate as the second heart rate minus the first average heart rate; determining a first probability of dehydration based, at least in part, on the change in heart rate; and outputting the first probability of dehydration.

Claims

1. A method comprising:

receiving heart rate data associated with a heart rate of a person from a first sensor configured to be worn externally on a body of the person;

receiving posture data associated with a posture of the person from a second sensor;

determining, via a processor, that a first posture of the person satisfies a first posture criteria for a first predetermined time period;

determining, via the processor, a first heart rate for the person based on the heart rate data, the first heart rate associated with the first predetermined time period;

determining, via the processor, that the posture of the person transitions from the first posture to a second posture within a second time period after the first predetermined time period;

if the length of the second time period is within a predetermined time period;

determining, via the processor, that the second posture of the person satisfies a second posture criteria for a third time period, the third time period being after the second time period;

determining, via the processor, a second heart rate for the person based on the heart rate data, the second heart rate associated with the third time period;

determining, via the processor, a change in heart rate based on a difference between the second heart rate and the first heart rate; and

determining, via the processor, a probability of dehydration based, at least in part, on the change in heart rate.

2. The method of claim 1, wherein the determining the probability of dehydration includes dividing the change in heart rate by a baseline change in heart rate.

3. The method of claim 1, further comprising:

comparing the second heart rate with a heart rate threshold; and

outputting a signal configured to alert the person of the probability of dehydration when the probability of dehydration exceeds a dehydration risk threshold and when the second heart rate is below the heart rate threshold.

4. The method of claim 1, wherein said first posture criteria is associated with sitting.

5. The method of claim 1, wherein the first posture criteria is associated with laying down.

6. The method of claim 1, wherein the first posture criteria is associated with at least one of sitting or laying down, and the second posture criteria is associated with standing.

7. The method of claim 1 further comprising:

determining, using data received from at least a third sensor coupled with the body of the person, whether the person is experiencing panic or is perspiring, or determining an activity level of the person during the third time period; and

outputting a signal configured to alert the person of the probability of dehydration when the probability of dehydration exceeds a dehydration risk threshold and when the person is experiencing panic or is perspiring, or the activity level is below an activity threshold.

8. A computer program stored in a non-transitory computer readable medium and executable by a computer system, the computer program comprising code to cause the computer system to:

determine that a first posture of a person satisfies a first posture criteria during a first predetermined time period;

determine a first heart rate of the person associated with the first predetermined time period;

determine that the posture of the person transitions from the first posture to a second posture within a second time period after the first predetermined time period;

if the length of the second time period is within a predetermined time period, the computer program further comprising code to cause the computer system to;

determine that the second posture of the person satisfies a second posture criteria for a third time period, the third time period being after the second time period;

determine a second heart rate of the person associated with the third time period;

determine an activity level of the person associated with the third time period;

determine a change in heart rate, the change in heart rate being a difference between the second heart rate and the first heart rate;

determine a probability of dehydration based, at least in part, on the change in heart rate; and

output an alert configured to alert the person of the probability of dehydration when the probability of dehydration exceeds a dehydration risk threshold and when the activity level of the person associated with the third time period is below an activity threshold.

9. The computer program of claim 8, wherein the code to cause the computer system to determine the probability of dehydration includes code to cause the computer system to divide the change in heart rate by a baseline change in heart rate.

10. The computer program of claim 8, wherein the first posture criteria is associated with at least one of sitting or laying down, and the second posture criteria is associated with standing.

11. The computer program of claim 8, wherein the code to cause the computer system to determine the first heart rate includes code to cause the computer system to determine the first heart rate based on heart rate data received from a sensor configured to be worn externally on a body of the person.

12. The computer program of claim 8, wherein the activity threshold is configured to prevent the alert from being output when the activity level of the person is elevated above the activity threshold due to exercise.

13. A method, comprising:

receiving, from a first sensor, an indication of a first posture of a person during a first predetermined time period;

determining, via a processor, a first heart rate of the person, the first heart rate being associated with the first predetermined time period and based on heart rate data received from a second sensor configured to be worn externally on a body of the person;

receiving, from the first sensor, an indication of a transition of the person from the first posture to a second posture during a second time period, the second time period being after the first predetermined time period;

if the length of the second time period is within a predetermined time period;

determining, via the processor, that the second posture of the person satisfies a second posture criteria for a third time period, the third time period being after the second time period;

determining, via the processor, a second heart rate of the person associated with the third time period, the second heart rate determined based on heart rate data received from the second sensor;

determining, via the processor, a probability of dehydration based, at least in part, on the first heart rate and the second heart rate.

14. The method of claim 13, wherein the determining the probability of dehydration is based, at least in part, on dividing a difference between the first heart rate and the second heart rate by a baseline change in heart rate.

15. The method of claim 13, further comprising:

comparing the second heart rate with a heart rate threshold; and

outputting the probability of dehydration when the second heart rate is below the heart rate threshold.

16. The method of claim 13, wherein the indication of the transition of the person from the first posture to the second posture is associated with the person moving from at least one of sitting or laying down to standing.

17. The method of claim 13, wherein at least one of the indication of the first posture or the indication of the transition of the person from the first posture to the second posture is received from an accelerometer.

18. The method of claim 13, wherein the determining the probability of dehydration is based, at least in part, on dividing a difference between the first heart rate and the second heart rate by a baseline change in heart rate, the baseline change in heart rate associated with at least one of an age, a weight, a gender, a fitness level, or an ambient temperature.

19. The method of claim 13, further comprising transmitting a wireless signal when the probability of dehydration exceeds a threshold.