HANDHELD PHYSIOLOGICAL SENSOR

• US 20170188843A1
• Filed: 01/05/2016
• Published: 07/06/2017
• Est. Priority Date: 01/05/2016
• Status: Active Application

• Current Assignee: OtoSense, Inc. (Analog Devices, Inc.)
• Original Assignee: OtoSense, Inc. (Analog Devices, Inc.)
• Inventors: HAYWARD, Lauren Nicole Miller, COCHRAN, Jonas Dean, BANET, Matthew, DHILLON, Marshal Singh, PEDE, Susan Meeks, DEPTALA, Arthur
• Application Number:
  US14/988,689
• Publication Number:
  US 20170188843A1
• Time in Patent Office: Days
• CPC Class Codes: A61B 5/0008 Temperature signals
• CPC Class Codes: A61B 5/0015 characterised by features of the telemetry system
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• 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 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• 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 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• 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 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0809 by impedance pneumography
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/332 Portable devices specially adapted therefor
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/4872 Body fat
• 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 5/6824 : Arm or wrist
• CPC Class Codes: A61B 5/6825 : Hand
• CPC Class Codes: A61B 5/683 : Means for maintaining contact with the body A61B5/6802 takes precedence
• 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
• 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 5/7282 : Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence

Abstract

A handheld device measures all vital signs and some hemodynamic parameters from the human body and transmits measured information wirelessly to a web-based system, where the information can be analyzed by a clinician to help diagnose a patient. The system utilizes our discovery that bio-impedance signals used to determine vital signs and hemodynamic parameters can be measured over a conduction pathway extending from the patient'"'"'s wrist to a location on their thoracic cavity, e.g. their chest or navel. The device'"'"'s form factor can include re-usable electrode materials to reduce costs. Measurements made by the handheld device, which use the belly button as a ‘fiducial’ marker, facilitate consistent, daily measurements, thereby reducing positioning errors that reduce accuracy of standard impedance measurements. In this and other ways, the handheld device provides an effective tool for characterizing patients with chronic diseases, such as heart failure, renal disease, and hypertension.

Claims

1. A system for measuring a physiological parameter from a patient, comprising:

a housing configured to receive the patient'"'"'s wrist and having first and second electrodes that are each configured and arranged to contact the wrist, near each other, when the wrist is received within the housing, with at least one of the first and second electrodes being inflatable and connected to a pneumatic inflation system; and

a surface connected to the housing and having third and fourth electrodes that are each configured and arranged to contact a second part of the patient'"'"'s body, near each other, when the housing receives the patient'"'"'s wrist while simultaneously being pressed against the second part of the patient'"'"'s body;

wherein the first and third electrodes are configured to inject electrical current into the patient'"'"'s body at their respective points of contact with the patient'"'"'s body and the second and fourth electrodes are configured to measure a first and a second biometric signal, respectively;

the system further comprising a processing system configured to process the first and second biometric signals to determine the physiological parameter.

2. The system of claim 1, wherein at least one of the first and second electrodes comprises an electrode material disposed on an inflatable bladder.

3. The system of claim 2, wherein the electrode material is a conductive fabric.

4. The system of claim 3, wherein the conductive fabric is a stretchable fabric configured to stretch at least 25% along at least one dimension when the inflatable bladder is inflated.

5. The system of claim 2, wherein the electrode material is a conductive foam.

6. The system of claim 2, wherein both of the first and second electrodes are inflatable and connected to the pneumatic inflation system.

7. The system of claim 1, wherein the pneumatic system comprises a pump and a valve.

8. The system of claim 1, wherein the housing comprises first and second spaced-apart wall portions that form an opening in the housing in which the patient'"'"'s wrist is received, which wall portions are arranged so as to be located on opposite sides of the patient'"'"'s arm when it is inserted in the opening.

9. The system of claim 8, wherein the first and second wall portions extend from the surface.

10. The system of claim 8, wherein the first electrode is disposed on an inner surface of the first wall portion, and the second electrode is disposed on an inner surface of the second wall portion.

11. The system of claim 1, wherein the arm-receiving portion comprises an annular ring component that forms an opening to receive the wrist.

12. The system of claim 11, wherein the first and second electrodes are disposed on an inner surface of the annular ring component.

13. The system of claim 1, wherein at least one of the first and second electrical currents is modulated at a frequency between 50-100 kHz.

14. The system of claim 1, wherein at least one of the first and second electrical currents has an amplitude between 0.5 and 10 mA.

15. The system of claim 1, wherein the processing system is configured to process the first and second biometric signals to determine a time-dependent voltage, and further to process the time-dependent voltage to determine an impedance value.

16. The system of claim 1, wherein the processing system is configured to process the first and second biometric signals to determine a time-dependent voltage, and further to process the time-dependent voltage to determine one of a heart rate, respiration rate, stroke volume, and cardiac output.

17. The system of claim 1, wherein the processing system is configured to process the first and second biometric signals to determine a time-dependent phase, and further to process the time-dependent phase to determine an reactance value.

18. The system of claim 1, wherein the processing system is configured to process the first and second biometric signals to determine a time-dependent phase, and further to process the time-dependent phase to determine one of a heart rate, respiration rate, stroke volume, and cardiac output.

19. A system for measuring a physiological parameter from a patient comprising:

a housing configured to receive the patient'"'"'s arm and having an opening;

an inflatable electrode disposed within the opening and configured and arranged to contact the patient'"'"'s arm once inflated, the electrode being configured to measure one of a bioimpedance and a bioreactance signal that, with further processing, yields a first time-dependent physiological waveform;

an optical sensor connected to the housing and configured to measure a second time-dependent physiological waveform; and

a processing system configured to collectively process the first and second time-dependent physiological waveforms to determine the physiological parameter.

20. The system of claim 19, wherein both the first and second time-dependent physiological waveforms include heartbeat-induced pulses and the processing system is further configured to measure a time difference between a first feature on a pulse in the first time-dependent waveform and a second feature on a pulse in the second time-dependent waveform.

21. The system of claim 20, wherein at least one of the first and second features is a component of the heartbeat-induced pulse.

22. The system of claim 21, wherein the component is a one of a maximum point, onset of a pulse, and maximum of a derivative of a pulse.

23. The system of claim 20, wherein the processing system is further configured to process the time difference to determine a blood pressure value.