RESPIRATORY MONITORS AND MONITORING METHODS

• US 20110046499A1
• Filed: 05/04/2009
• Published: 02/24/2011
• Est. Priority Date: 05/14/2008
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Ikkink, Teunis Jan, Klewer, Jasper, durIic, Haris
• Granted Patent: US 10,052,048 B2
• Time in Patent Office: Days
• US Class Current: 600/534
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/113 occurring during breathing
• CPC Class Codes: A61B 7/003 Detecting lung or respiration noise
• CPC Class Codes: H04B 17/0085 using test signal generators

Abstract

A respiratory monitor comprises: a first sensor (20, 70) configured to generate a respiration-related motion monitoring signal (72) indicative of respiration related motion; a second sensor (20, 22, 80, 82) configured to generate a sound monitoring signal (84) indicative of respiration-related sound; and a signals synthesizer (90) configured to synthesize a respiratory monitor signal (46) based on the respiration-related motion monitoring signal and the respiration-related sound monitoring signal. A sensor for use in respiratory monitoring comprises an accelerometer (30) and a magnetometer (32) together defining a unitary sensor (20) configured for attachment to a respiring subject (10) so as to move as a unit responsive to respiration related motion of the respiring subject.

Claims

1. A respiratory monitor comprising:

a first sensor configured to generate a respiration-related motion monitoring signal indicative of respiration-related motion;

a second sensor configured to generate a sound monitoring signal indicative of respiration-related sound; and

a signals synthesizer configured to synthesize a respiratory monitor signal based on the respiration-related motion monitoring signal and the respiration-related sound monitoring signal.

2. The respiratory monitor as set forth in claim 1, wherein the first sensor and the second sensor comprise:

a sensor configured to generate a sensor signal indicative of both respiration-related motion and respiration-related sound;

a first filter configured to extract from the sensor signal a low frequency signal encompassing frequencies of respiration-related motion, the respiration-related motion monitoring signal being based on the low frequency signal; and

a second filter configured to extract from the sensor signal a high frequency signal encompassing frequencies of respiration-related sound, the respiration-related sound monitoring signal being based on the high frequency signal.

3. The respiratory monitor as set forth in claim 2, wherein the second sensor further comprises:

an envelope filter or extractor configured to generate an envelope signal corresponding to an envelope of the high frequency signal, the respiration-related sound monitoring signal being based on the envelope signal.

4. The respiratory monitor as set forth in claim 2, wherein the sensor comprises:

at least one accelerometer configured for attachment to a respiring subject.

5. The respiratory monitor as set forth in claim 4, wherein the at least one accelerometer is a single accelerometer, and the sensor further comprises:

a magnetometer coupled with the accelerometer such that the accelerometer and the magnetometer have a common orientation; and

a signal processor configured to generate the sensor signal based on an accelerometer signal output by the accelerometer and a magnetometer signal output by the magnetometer.

6. The respiratory monitor as set forth in claim 5, wherein the accelerometer and the magnetometer are monolithically integrated on a common substrate.

7. The respiratory monitor as set forth in claim 1, wherein the first sensor comprises:

an accelerometer;

a magnetometer configured to move with the accelerometer responsive to respiration-related motion; and

a signal processor configured to generate the respiration-related motion monitoring signal based on an accelerometer signal output by the accelerometer and a magnetometer signal output by the magnetometer.

8. The respiratory monitor as set forth in claim 1, wherein the first sensor comprises:

at least one accelerometer.

9. The respiratory monitor as set forth in claim 1, wherein:

the first sensor includes at least one sensor selected from a group consisting of an accelerometer, a gyroscope, a tilt sensor, and a magnetometer; and

the second sensor includes at least one sensor selected from a group consisting of an accelerometer, a microphone, a hydrophone, a piezoelectric transducer, and a vibration transducer.

10. A respiratory monitoring method comprising:

acquiring a respiration-related motion monitoring signal indicative of respiration-related motion of a respiring subject;

acquiring a sound monitoring signal indicative of respiration-related sound generated by the respiring subject; and

synthesizing a respiratory monitor signal based on the respiration-related motion monitoring signal and the respiration-related sound monitoring signal.

11. The respiratory monitoring method as set forth in claim 10, wherein the acquiring operations comprise:

acquiring a sensor signal indicative of both respiration-related motion and respiration-related sound;

deriving the respiration-related motion monitoring signal from frequency components of the sensor signal encompassing frequencies of respiration-related motion; and

deriving the respiration-related sound monitoring signal from frequency components of the sensor signal encompassing frequencies of respiration-related sound.

12. The respiratory monitoring method as set forth in claim 11, wherein the deriving of the respiration-related sound monitoring signal comprises:

filtering the sensor signal to generate a filtered signal encompassing frequencies of respiration-related sound; and

extracting an envelope of the filtered signal.

13. The respiratory monitoring method as set forth in claim 11, wherein the acquiring of the sensor signal comprises:

acquiring an accelerometer signal.

14. A sensor for use in respiratory monitoring, the sensor comprising:

an accelerometer; and

a magnetometer defining together with the accelerometer a unitary sensor configured for attachment to a respiring subject so as to move as a unit responsive to respiration-related motion of the respiring subject.

15. The respiratory monitor as set forth in claim 14, further comprising:

a signal processor configured to generate a respiration-related signal based on an accelerometer signal output by the accelerometer and a magnetometer signal output by the magnetometer.