Daytime/nighttime respiration rate monitoring

• US 20090198139A1
• Filed: 04/02/2009
• Published: 08/06/2009
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: Aaron Lewicke, John D. Hatlestad, Yi Zhang
• Original Assignee: Aaron Lewicke, John D. Hatlestad, Yi Zhang
• Inventors: Zhang, Yi, Hatlestad, John D., Lewicke, Aaron
• Granted Patent: US 7,704,215 B2
• Time in Patent Office: Days
• US Class Current: 600/484
• 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 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

A device and method can monitor or trend a patient'"'"'s respiration rate measurements according to the time of day. The device, which may be implantable or external, collects and classifies respiration rate measurements over time. The trended information about particular classes of respiration rate measurements is then communicated to a remote external device, which in turn provides an indication of heart failure decompensation. Examples of classes of respiration rate measurements include a daily maximum respiration rate value, a daily minimum respiration rate value, a daily maximum respiration rate variability value, a daily minimum respiration rate variability value, and a daily central respiration rate value. These respiration rate measurements can be further classified into daytime or nighttime respiration rate measurements.

Claims

1. A method comprising:

detecting a respiration signal from a subject;

determining respiration rate or interval measurements from the respiration signal;

classifying the respiration rate or interval measurements into at least one class of respiration rate or interval measurements, and associating a specified time of day with at least one class;

trending at least one of;

(1) time of day of occurrence information about the classified respiration rate or interval measurements, or (2) respiration rate or interval measurement information repeatedly, over a period of multiple days, during a specified one of a daytime subperiod or a nighttime subperiod, wherein the specified one of the daytime subperiod or the nighttime subperiod corresponds to a like time of day during each of the multiple days; and

providing a heart failure decompensation indication using the trended information.

2. The method of claim 1, wherein determining respiration rate or interval measurements from the respiration signal includes excluding one or more periods of apneic breathing.

3. The method of claim 1, wherein classifying the respiration rate or interval measurements includes classifying into at least one of the following classes:

a daily maximum respiration rate value, a daily minimum respiration rate value, a daily maximum respiration rate variability value, a daily minimum respiration rate variability value, and a daily central tendency of respiration rate value.

4. The method of claim 1, wherein classifying the respiration rate or interval measurements includes classifying into a specified one of daytime respiration rate or interval measurements or nighttime respiration rate or interval measurements.

5. The method of claim 4, comprising:

collecting the specified one of the daytime or nighttime respiration rate or interval measurements;

performing a statistical analysis on the collected respiration rate or interval measurements; and

providing the heart failure decompensation indication using a result of the statistical analysis.

6. The method of claim 5, comprising providing the heart failure decompensation indication by detecting a change over time in a measure of centrality of the collected respiration rate or interval measurements.

7. The method of claim 5, comprising providing the heart failure decompensation indication by detecting a change over time in a measure of spread or variance of the collected respiration rate or interval measurements.

8. The method of claim 4, comprising:

integrating or otherwise lowpass filtering the collected respiration rate or interval measurements to obtain lowpass filtered collected respiration rate or interval measurements;

detecting a change in the lowpass filtered collected respiration rate or interval measurements over a period of time; and

providing the heart failure decompensation indication using the detected change in the lowpass filtered collected respiration rate or interval measurements.

9. The method of claim 4, comprising:

forming a histogram of the collected respiration rate or interval measurements;

updating the histogram over time;

detecting a change in the histogram over time; and

providing the heart failure decompensation indication using the detected change in the histogram.

10. The method of claim 4, wherein classifying the respiration rate or interval measurements includes classifying into nighttime respiration rate or interval measurements.

11. The method of claim 4, comprising comparing daytime respiration rate or interval measurements to nighttime respirations rate or interval measurements.

12. The method of claim 1, comprising recording, in correspondence with the respiration rate or interval measurements, at least one of a corresponding posture, activity level, and angle of reclination.

13. The method of claim 1, comprising recording, in correspondence with the respiration rate or interval measurements, at least one of a heart rate, heart sound, heart rate variability, blood pressure, and impedance.

14. The method of claim 1, wherein the trending comprises trending time of day of occurrence information about the classified respiration rate or interval measurements.

15. The method of claim 1, wherein the trending comprises trending respiration rate or interval measurement information repeatedly, over a period of multiple days, during a specified one of a daytime subperiod or a nighttime subperiod, wherein the specified one of the daytime subperiod or the nighttime subperiod corresponds to a like time of day during each of the multiple days.

16. The method of claim 15, wherein the specified one of the daytime subperiod or the nighttime subperiod is the daytime subperiod.

17. The method of claim 15, wherein the specified one of the daytime subperiod or the nighttime subperiod is the nighttime subperiod.

18. The method of claim 1, comprising recording a corresponding posture in correspondence with the respiration rate or interval measurements.

19. The method of claim 1, comprising recording a corresponding physical activity level in correspondence with the respiration rate or interval measurements.

20. The method of claim 1, comprising recording a corresponding angle of reclination in correspondence with the respiration rate or interval measurements.

21. The method of claim 1, comprising recording a corresponding heart rate in correspondence with the respiration rate or interval measurements.

22. The method of claim 1, comprising recording a corresponding heart sound in correspondence with the respiration rate or interval measurements.

23. The method of claim 1, comprising recording a corresponding heart rate variability in correspondence with the respiration rate or interval measurements.

24. The method of claim 1, comprising recording a corresponding blood pressure in correspondence with the respiration rate or interval measurements.

25. The method of claim 1, comprising recording a corresponding impedance in correspondence with the respiration rate or interval measurements.