HEALTH MONITORING SYSTEMS AND METHODS

• US 20190029599A1
• Filed: 09/25/2018
• Published: 01/31/2019
• Est. Priority Date: 10/07/2012
• Status: Active Grant

• Current Assignee: RDS SAS
• Original Assignee: Rhythm Diagnostic Systems, Inc.
• Inventors: Golda, George Stefan, Moyer, Daniel Van Zandt, Marriott, Mark P., Eletr, Sam, O'Neil, Bruce
• Granted Patent: US 10,863,947 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 2560/0295 adapted for recording user messages or annotations
• CPC Class Codes: A61B 2560/0412 Low-profile patch shaped housings
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• 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 5/02125 of pulse wave propagation time
• CPC Class Codes: A61B 5/02141 Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits A61B5/02233, A61B5/0235 take precedence
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/259 using conductive adhesive means, e.g. gels
• CPC Class Codes: A61B 5/282 Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/335 using integrated circuit memory devices
• CPC Class Codes: A61B 5/352 : Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 5/6828 : Leg
• CPC Class Codes: A61B 5/6833 : Adhesive patches
• 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 5/7207 : of noise induced by motion artifacts
• CPC Class Codes: A61B 5/721 : using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/7214 : using signal cancellation, e.g. based on input of two identical physiological sensors spaced apart, or based on two signals derived from the same sensor, for different optical wavelengths
• CPC Class Codes: A61B 5/7275 : Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor

Abstract

Systems, methods and devices for reducing noise in health monitoring including monitoring systems, methods and/or devices receiving a health signal and/or having at least one electrode or sensor for health monitoring.

Claims

1. A method of measuring oxygen saturation in an individual, the method comprising the steps of:

measuring an electrocardiogram signal over multiple heart beats;

measuring one or more pulse oximetry signals over multiple heart beats such that the electrocardiogram signal and the one or more pulse oximetry signals are in time concordance over one or more heart beats;

comparing a portion of the electrocardiogram signal and the one or more pulse oximetry signals in time concordance over one or more heart beats to determine a constant component and a primary periodic component of each of the one or more pulse oximetry signals; and

determining oxygen saturation from the constant components and primary periodic components of the one or more pulse oximetry signals.

2. The method of claim 1 wherein said pulse oximetry signals include a reflective infrared signal and a reflective red light signal.

3. The method of claim 1 wherein said step of comparing includes defining intervals of said pulse oximetry signal based on characteristics of said electrocardiogram signal and averaging values of said pulse oximetry signal over a plurality of such intervals.

4. The method of claim 3 wherein said constant components and said primary periodic components of said pulse oximetry signals are determined from said average values.

5. The method of claim 1 wherein said electrocardiogram signal includes an R wave signal each with a peak value in each of said heart beats and said intervals are determined with respect to the peak values of the R wave signals.

6. The method of claim 1 wherein said electrocardiogram signal and said pulse oximetry signal are measured from a chest location on said individual.

7. A device for monitoring a physiological parameter, the device being adapted to be adhered to the skin of a subject for the physiological parameter monitoring;

the device comprising;

a substrate;

a conductive sensor connected to the substrate, and one or both of;

a plurality of pulse oximetry sensors connected to the substrate, and,

a plurality of light sources for one or more wavelengths.

8. A device according to claim 7 wherein the plurality of pulse oximetry sensors and/or light sources provide for interrogation of a wider area of capillary bed in order to reduce local motion artifact effects.

9. A device for monitoring a physiological parameter, the device being adapted to be adhered to the skin of a subject for the physiological parameter monitoring;

the device comprising;

a substrate;

a conductive sensor connected to the substrate, and

circuitry for reducing errors caused by ambient light using a correlated double sampling technique;

comprising;

a light sensor;

first and second switches and;

first and second capacitors,

wherein the first capacitor is in series with the light sensor, and the second capacitor is in parallel with the output, and the first and second switches are disposed between the output and ground to alternatively provide output or shunt to ground.

10. A device according to claim 9 further including a resistor in parallel with the other circuit elements.

11. A device according to claim 9 wherein the first capacitor is C1, the second capacitor is C2, the first switch is S1, the second switch is S2 and

wherein when the light sources are turned off, and switch S1 is closed, and switch S2 is open;

charge proportional to the noise signal accumulates on C1, and then switch S1 is opened and, then, the voltage on C1 is equal to the noise signal voltage; and

,

wherein, next, the light signal may be measured;

switch S2 is closed, and charge is allowed to flow through C1 and C2 in series; and

, then, S2 is opened, and the voltage is held on C2 until the next measurement cycle when the whole process is repeated; and

,

if C1 is much larger than C2, nearly all the voltage will appear on C2, and the voltage on C2 will be equal to the noise-free signal (s);

or, otherwise, the voltage on C2 will be a linear combination of the previous C2 voltage (p) and the noise-free signal;

(C2*s+C1*p)/(C1+C2).

12. A device according to claim 11 wherein either one of:

the effect is of applying a first-order, low-pass, IIR discrete-time filter to the signal;

or,

if this filtering effect is not desired, the voltage on C2 may be discharged to zero before the signal is measured each cycle, the signal being held on C2 is;

(C2*s)/(C1+C2).

13. A device according to claim 10;

wherein one or more of;

a trans-impedance amplifier is used in place of resistor R, a phototransistor in place of the light sensor, and FETs in place of the first and second switches;

or the output may be followed by one or more of additional buffering, amplification, filtering and processing stages.

14. A device for reducing noise in health monitoring including a wearable health monitoring device having at least one sensor for health monitoring;

the wearable health monitoring device having a composite adhesive having at least one conductive portion applied adjacent the sensor; and

, including adaptations for the at least one sensor to have increased effectiveness in receiving signals with reduced noise;

wherein the adaptations include a convex lens.

15. A device according to claim 14 wherein the convex lens is adapted to be disposed in operative contact with a wearer'"'"'s/user'"'"'s skin.

16. A device according to claim 14 wherein the convex lens is adapted to be disposed in operative contact with a wearer'"'"'s/user'"'"'s skin at or adjacent the wearer'"'"'s/user'"'"'s forehead or chest.

17. A device according to claim 14 wherein the convex lens is an encapsulant.

18. A device according to claim 17 wherein the convex lens encapsulant encapsulates the sensor.

19. A device according to claim 17 wherein the convex lens encapsulant encapsulates the sensor and is in operative contact with the sensor not allowing an interference airgap between the sensor and the encapsulant.

20. A device according to claim 17 further comprising one or more LEDs wherein the convex lens encapsulant encapsulates the one or more LEDs.

21. A device according to claim 17 wherein the convex lens encapsulant encapsulates the one or more LEDs and is in operative contact with at least one of the one or more LEDs not allowing an interference airgap between the at least one of the one or more LEDs and the encapsulant.

22. A device according to claim 14 wherein the convex lens is one or more of clear, colorless, silicone and medical grade silicone.

23. A device according to claim 14 wherein the adaptations are used for pulse oximetry.

24. A device according to claim 14 further comprising one or more functionalities including one or more of EKG, PPG and wearer acceleration.

25. A device according to claim 14 further comprising one or more functionalities including one or both of driven right leg and/or proxy driven right leg.

26. A device according to claim 14 further comprising a driven or proxy driven electrode on a wearer chest or a wearer forehead.

27. A device according to claim 26 wherein the adaptation is disposed for and configured for maintained indented operative contact with the wearer'"'"'s/user'"'"'s skin.

28. A device according to claim 14 providing for transmission of LED waves therethrough to the wearer'"'"'s/user'"'"'s skin without interfering transmission thereinto.

29. A device according to claim 28 providing for reception of reflected transmissions of LED waves therethrough from the wearer'"'"'s/user'"'"'s skin to the sensor without interfering transmission therethrough.

30. A device according to claim 22 that is made from medical grade silicone that is one or more of substantially clear, substantially colorless, substantially soft, substantially low durometer, tacky gel, or has very high-tack adhesives embedded on both sides.

31. A device according to claim 30 wherein the silicone with double-sided adhesive provides one or both

conformance of the lens to one or both the electronic sensors and skin, or

exhibition of motion artifact reduction by limiting movement between the skin-lens-sensor interface.

32. A device according to claim 30 that is specially configured such that it can be trapped between layers of the composite adhesive strip of a wearable health monitoring device, with a raised portion the size of the rectangular opening in the adhesive strip that allows the lens to protrude slightly on the patient side of the adhesive strip.

33. A device for a health sensor;

comprising a lens being

configured for operative contact with the wearer'"'"'s/user'"'"'s skin; and

configured for providing noninterfering light pipe transmission of energy waves therethrough.