Physiological monitoring devices and methods using optical sensors

1. A monitoring device configured to be attached to a subject, the monitoring device comprising:

a photoplethysmography (PPG) sensor configured to measure a plurality of physiological parameters from the subject, wherein each physiological parameter is measured in a respective one of a plurality of time intervals;

at least one motion sensor configured to detect an activity state of the subject; and

at least one processor coupled to the PPG sensor and the at least one motion sensor, wherein the at least one processor instructs the PPG sensor to measure a first one of the plurality of physiological parameters if the activity state is at or above a threshold, and to measure a second one of the plurality of physiological parameters if the activity state is below the threshold.

2. The monitoring device of claim 1 , wherein the at least one processor is further configured to cause an optical emitter of the PPG sensor to have a different polling rate in each of the respective time intervals.

3. The monitoring device of claim 1 , wherein the at least one processor is further configured to cause an optical detector of the PPG sensor to have a different sampling rate in each of the respective time intervals.

4. The monitoring device of claim 1 , wherein the at least one processor is further configured to cause an optical detector of the PPG sensor to emit a different wavelength of light or a different set of wavelengths of light during each of the respective time intervals.

5. The monitoring device of claim 1 , wherein the PPG sensor is configured to measure subject heart rate in a first one of the time intervals, subject RRi in a second one of the time intervals, subject blood pressure in a third one of the time intervals, and subject breathing rate in a fourth one of the time intervals.

6. The monitoring device of claim 1 , wherein the monitoring device is configured to be positioned at or within an ear of the subject.

7. The monitoring device of claim 1 , wherein the monitoring device is configured to be secured to an appendage of the subject.

8. A method of monitoring a subject via a monitoring device attached to the subject, wherein the monitoring device comprises a photoplethysmography (PPG) sensor configured to measure a plurality of physiological parameters from the subject, at least one motion sensor, and at least one processor, the method comprising:

detecting an activity state of the subject via the at least one motion sensor; and

instructing the PPG sensor to measure a first one of the plurality of physiological parameters if the activity state is at or above a threshold, and to measure a second one of the plurality of physiological parameters if the activity state is below the threshold.

9. The method of claim 8 , wherein the monitoring device is configured to be positioned at or within an ear of the subject.

10. The method of claim 8 , wherein the monitoring device is configured to be secured to an appendage of the subject.

11. A monitoring device configured to be attached to a subject, the monitoring device comprising:

a photoplethysmography (PPG) sensor configured to measure subject heart rate, subject RRi, subject blood pressure, and subject breathing rate;

at least one motion sensor configured to detect an activity state of the subject; and

at least one processor coupled to the PPG sensor and the at least one motion sensor, wherein the at least one processor is configured to instruct the PPG sensor to measure heart rate and/or breathing rate if the activity state of the subject is at or above a threshold, and to measure RRi and/or blood pressure if the activity state of the subject is below the threshold.

12. The monitoring device of claim 11 , wherein the PPG sensor is configured to measure the subject heart rate in a first one of a plurality of time intervals, the subject RRi in a second one of the plurality of time intervals, the subject blood pressure in a third one of the plurality of time intervals, and the subject breathing rate in a fourth one of the plurality of time intervals.

13. The monitoring device of claim 12 , wherein the at least one processor is configured to cause an optical emitter of the PPG sensor to have a different polling rate in at least two of the respective time intervals.

14. The monitoring device of claim 12 , wherein the at least one processor is configured to cause an optical detector of the PPG sensor to have a different sampling rate in at least two of the respective time intervals.

15. The monitoring device of claim 12 , wherein the at least one processor is configured to cause an optical detector of the PPG sensor to emit a different wavelength of light or a different set of wavelengths of light during at least two of the respective time intervals.

16. The monitoring device of claim 11 , wherein the monitoring device is configured to be positioned at or within an ear of the subject.

17. The monitoring device of claim 11 , wherein the monitoring device is configured to be secured to an appendage of the subject.

18. A method of monitoring a subject via a monitoring device attached to the subject, wherein the monitoring device comprises a photoplethysmography (PPG) sensor configured to measure subject heart rate, subject RRi, subject blood pressure, and subject breathing rate, at least one motion sensor, and at least one processor, the method comprising:

detecting an activity state of the subject via the at least one motion sensor; and

instructing the PPG sensor to measure heart rate and/or breathing rate if the activity state of the subject is at or above a threshold, and to measure RRi and/or blood pressure if the activity state of the subject is below the threshold.

19. The method of claim 18 , wherein the monitoring device is configured to be positioned at or within an ear of the subject.

20. The method of claim 18 , wherein the monitoring device is configured to be secured to an appendage of the subject.