TISSUE HYDRATION MONITOR

• US 20190328323A1
• Filed: 04/25/2019
• Published: 10/31/2019
• Est. Priority Date: 04/27/2018
• Status: Active Grant

• Current Assignee: Hydrostasis, Inc.
• Original Assignee: Hydrostasis, Inc.
• Inventors: Chen, Debbie K.
• Granted Patent: US 10,966,655 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/4261 Evaluating exocrine secretion production A61B3/101 takes precedence
• CPC Class Codes: A61B 5/443 Evaluating skin constituents, e.g. elastin, melanin, water
• CPC Class Codes: A61B 5/4875 Hydration status, fluid retention of the body
• CPC Class Codes: A61B 5/6813 Specially adapted to be attached to a specific body part A61B5/6802 takes precedence
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• CPC Class Codes: A61B 5/6833 Adhesive patches
• CPC Class Codes: A61B 5/7207 of noise induced by motion artifacts
• CPC Class Codes: A61B 5/7267 involving training the classification device
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence
• CPC Class Codes: A61B 5/7455 characterised by tactile indication, e.g. vibration or electrical stimulation
• 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

Abstract

A tissue hydration monitor and method includes a sensor module having a plurality of LEDs positioned to emit a plurality of different wavelengths of light toward the user'"'"'s skin and a detector that detects light transmitted and reflected through the user'"'"'s skin to generate signals corresponding to an intensity of detected light at each of the different wavelengths. A processor/controller module generates a baseline hydration level based on the received signals, calculates a relative hydration level, and generates an output indicative of relative hydration personalized to the user. The housing is secured against the user'"'"'s skin by an adhesive patch or a strap.

Claims

1. A tissue hydration monitor, comprising:

a housing configured to be disposed against a user'"'"'s skin;

a sensor module disposed within the housing, the sensor module comprising;

a plurality of LEDs configured to emit light toward the user'"'"'s skin at a plurality of different wavelengths; and

a detector configured to detect light from each of the plurality of LEDs transmitted and reflected through the user'"'"'s skin over a period of time and generate signals corresponding to an intensity of detected light at each of the different wavelengths;

a processor/controller module configured for receiving signals from the sensor module, executing an algorithm for generating a baseline hydration level based on the received signals, calculating a relative hydration level at time points within the period of time, and generating an output indicative of relative hydration at the time points; and

a power supply configured to provide power to the sensor module and the processor/controller module.

2. The tissue hydration monitor of claim 1, further comprising an adhesive material applied to the housing to removably seal the sensor to the user'"'"'s skin.

3. The tissue hydration monitor of claim 2, wherein the adhesive material has the form of a patch dimensioned to seal the perimeter of the housing against the user'"'"'s skin to produce a substantially light-tight seal.

4. The tissue hydration monitor of claim 2, wherein the patch comprises at least a breathable material and a water resistant material.

5. The tissue hydration monitor of claim 1, further comprising a strap attached to the housing for retaining the housing against the user'"'"'s skin.

6. The tissue hydration monitor of claim 1, wherein the plurality of different wavelengths comprise wavelengths absorbed by oxygenated hemoglobin, deoxygenated hemoglobin, lipid, and water.

7. The tissue hydration monitor of claim 1, wherein the plurality of different wavelengths comprise 740 nm, 850 nm, 940 nm and 1450 nm.

8. The tissue hydration monitor of claim 1, further comprising a communication module in communication with the processor/controller module for transmitting data to a remote mobile device for displaying the output.

9. The tissue hydration monitor of claim 8, wherein the mobile device has an application installed therein comprising instructions for further processing of the output.

10. The tissue hydration monitor of claim 1, further comprising an indicator responsive to the processor/controller module for generating an alert indicative of a predetermined deviation from the baseline hydration level.

11. The tissue hydration monitor of claim 10, wherein the indicator comprises an LED disposed to emit light from a surface of the housing.

12. The tissue hydration monitor of claim 10, wherein the predetermined deviation is a change of less than or equal to ±

2%.

13. The tissue hydration monitor of claim 1, further comprising a light shield disposed around the detector to prevent stray light from impinging upon the detector.

14. The tissue hydration monitor of claim 1, wherein the period of time includes periods of user activity ranging from resting to exercising, wherein the baseline hydration range is generated at time points during resting and the relative hydration level is calculated at multiple time points during exercising.

15. A method for monitoring hydration in a subject, the method comprising:

placing a sensor device against the skin of the subject, the sensor device comprising a plurality of LEDs configured to emit light toward the user'"'"'s skin at a plurality of different wavelengths;

detecting light from each of the plurality of LEDs transmitted and reflected through the user'"'"'s skin over a period of time and generating intensity signals corresponding to light at each of the different wavelengths;

generating a baseline hydration level from the intensity signals;

calculating a relative hydration level relative to the baseline hydration level at a plurality of time points within the period of time; and

generating an output indicative of relative hydration at the time points.

16. The method of claim 15, wherein the plurality of different wavelengths comprise wavelengths absorbed by oxygenated hemoglobin, deoxygenated hemoglobin, lipid, and water.

17. The method of claim 15, wherein the plurality of different wavelengths comprise 740 nm, 850 nm, 940 nm and 1450 nm.

18. The method of claim 15, further comprising transmitting data to a remote mobile device for displaying the output.

19. The method of claim 15, further comprising generating an alert indicative of a predetermined deviation from the baseline hydration level.

20. The method of claim 15, wherein the predetermined deviation is a change of less than or equal to ±

2%.

21. The method of claim 15, wherein the period of time includes periods of subject activity ranging from resting to exercising, wherein the baseline hydration range is generated at time points during resting and the relative hydration level is calculated at multiple time points during exercising.