Physiological signal monitoring and apparatus therefor
Aspects of the present disclosure are directed to apparatuses and methods for monitoring vital signs from a human being. Various such aspects involve an apparatus or method involving the monitoring of vital signs in a manner that facilitates enhanced characterization of physiological conditions. In many embodiments, two or more such vital signs are monitored. A signal acquisition, digitization, and computing module removing noise, extracts information useful for diagnosing a health or fitness characteristic of the human being, and/or compresses information to reduce data volume. A wireless communications circuit transmits the vital signs to a receiver.
1. An apparatus configured and arranged to monitor two or more vital signs from a human being, the apparatus comprising:
two or more sensing circuit components, including at least two of the following:
at least two electrodes configured and arranged to sense an ECG signal from the human being,
at least two monochromatic LEDs and light sensors configured and arranged to sense one or more photoplethysmography (PPG) signals from the human being,
a temperature sensor, and
at least two electrodes configured and arranged to sense a thoracic impedance signal from the human being;
a signal acquisition, digitization, and computing module, including circuitry, configured and arranged to compress information to reduce data volume to provide >7× compression while maintaining QSR of >95%, via the two or more sensing circuit components, to produce data characterizing the two or more vital signs; and
a wireless communications circuit configured and arranged to transmit the data characterizing the two or more vital signs to a receiver.
2. The apparatus of claim 1 , wherein the computing module is configured and arranged to compute one or more of heart rate, heart rate variability, oxygen saturation, and CO2 saturation.
3. The apparatus of claim 2 , wherein the computing module is configured and arranged to detect one or more of the following arrhythmias: atrial fibrillation, tachycardia, pause, and bradycardia.
4. The apparatus of claim 1 , wherein the computing module is configured and arranged to perform one or more of removing noise and extracting information useful for diagnosing a health or fitness characteristic of the human being.
5. The apparatus of claim 1 , wherein the computing module is configured and arranged to detect tachycardia, bradycardia, pause and atrial fibrillation in real time.
6. The apparatus of claim 1 , wherein the computing module is configured and arranged to extract clinically relevant information from the monitored vital signs and to provide concurrent statistical evaluation of the information to assess and predict the patient's condition in real time.
7. The apparatus of claim 1 , wherein each of the at least two monochromatic LEDs is configured and arranged to illuminate tissue by transmitting light at a different wavelength relative to another of the at least two LEDs, the light being transmitted by one of the at least two monochromatic LEDs one at a time, in sequence, further including:
a sensor positioned to sense light exiting the tissue; and
circuitry configured and arranged to denoise a signal acquired by the sensor, by digitizing the signal;
decomposing respective portions of the digitized signal corresponding to light received on each of the different wavelengths into subcomponents;
identifying ones of the subcomponents corresponding to noise; and
reconstructing a denoised PPG signal from the subcomponents, based on the identification of the ones of the subcomponents corresponding to noise, using an inverse transform.
8. The apparatus of claim 7 , wherein identifying the ones of the subcomponents corresponding to noise includes utilizing a blind source separation technique to identify the subcomponents corresponding to noise.
9. The apparatus of claim 7 , wherein identifying the ones of the subcomponents corresponding to noise includes:
performing one or more of principal component analysis and independent component analysis on the subcomponents, and
identifying ones of the subcomponents corresponding to noise based on the one of the principal component analysis and independent component analysis.
10. The apparatus of claim 1 , wherein the temperature sensor is configured and arranged to measure temperature via a nasal cannula.
11. The apparatus of claim 1 , wherein the temperature sensor is configured and arranged to be inserted into a canal or the outer ear of the human being.
12. The apparatus of claim 1 , further including a PPG sensor configured and arranged for attachment to the human being's nasal septum, nasal alar, ear lobe, or for insertion into the human being's canal or ear.
13. The apparatus of claim 1 , wherein
the apparatus includes a battery, and
the battery and the signal acquisition, digitization, and computing module are configured and arranged to be supported at least in part by an anatomical feature of the human being's head.
14. The apparatus of claim 1 wherein
the apparatus includes a battery, and
the battery and the signal acquisition, digitization, and computing module are configured and arranged to be supported at least in part by an anatomical feature of the human being's neck.
15. The apparatus of claim 1 wherein
the apparatus includes a battery, and
the battery and the signal acquisition, digitization, and computing module are configured and arranged to be supported by an adhesive material attached to the human being's chest.
16. The apparatus of claim 1 wherein
the apparatus includes a battery and a strap, and
the battery and the signal acquisition, digitization, and computing module are configured and arranged to be supported by the human being's arm via the strap.
17. The apparatus of claim 1 wherein
the apparatus includes a battery and a strap, and
the battery and the signal acquisition, digitization, and computing module are configured and arranged to be supported by the strap with the strap at least partially elastically surrounding the human being's chest or abdomen.
18. An apparatus to monitor two or more vital signs from a human being, the apparatus comprising:
two or more sensing circuit components, including at least two of the following:
at least two electrodes configured and arranged to sense an ECG signal from the human being,
at least two monochromatic LEDs and light sensors configured and arranged to sense one or more photoplethysmography (PPG) signals from the human being,
a temperature sensor, and
at least two electrodes configured and arranged to sense a thoracic impedance signal from the human being;
a signal acquisition, digitization, and computing module, including circuitry, configured and arranged to perform one or more of removing noise, extracting information useful for diagnosing a health or fitness characteristic of the human being, and compressing information to reduce data volume, via the two or more sensing circuit components, wherein the computing module is configured and arranged to increase the signal-to-noise ratio (SNR) of an input ECG signal by >15 dB while maintaining a quality of signal reconstruction (QSR) of >95%; and
a wireless communications circuit configured and arranged to transmit the two or more vital signs to a receiver.
19. A method for monitoring two or more vital signs from a human being, the method comprising:
performing two or more of the following:
sensing an ECG signal from the human being,
sensing, via two or more monochromatic LEDs and light sensors, one or more photoplethysmography (PPG) signals from the human being,
sensing temperature, and
sensing, via at least two electrodes, a thoracic impedance signal from the human being;
compressing information to reduce data volume to provide >7× compression while maintaining QSR of >95%, to produce data characterizing the two or more vital signs based on the sensing; and
wirelessly transmitting the data characterizing the two or more vital signs to a receiver.
20. The method of claim 19 , further including performing one or more of removing noise and extracting information useful for diagnosing a health or fitness characteristic of the human being.