Respiration monitoring using respiration rate variability
Systems and methods provide for detecting respiration disturbances and changes in respiration disturbances, preferably by detecting variability in one or more respiration parameters. Respiration rate variability is determined for a variety of diagnostic and therapeutic purposes, including disease/disorder detection, diagnosis, treatment, and therapy titration. Systems and methods provide for generating a footprint, such as a two- or three-dimensional histogram, representative of a patient's respiration parameter variability, and generating one or more indices representative of quantitative measurements of the footprint.
1. A system, comprising:
a medical device comprising sensing circuitry;
detection circuitry coupled to the sensing circuitry, the detection circuitry configured to detect a patient respiration parameter of a patient; and
a processor coupled to the detection circuitry, the processor configured to generate a footprint comprising a mapping of a plurality of contour lines representative of the patient's respiration parameter variability using a respiration-modulated signal detected by the detection circuitry, generate one or more indices as quantitative measurements of the footprint, wherein a first one of the one or more indices is representative of a size of the footprint, analyze the footprint using the one or more indices to identify one or more patterns indicative of disordered breathing, assess the patient's health status based on the analysis of the footprint to identify the one or more disordered breathing patterns, and generate an output based on the assessment of the patient's health status.
2. The system of claim 1 , wherein the processor is configured to determine respiration rate based on the detected patient respiration parameter and the footprint is generated based on the patient's respiration rate variability.
3. The system of claim 1 , wherein the sensing circuitry comprises a minute ventilation sensor.
4. The system of claim 1 , wherein the processor is configured to determine tidal volume based on the detected patient respiration parameter and the footprint is based at least in part on the patient's tidal volume variability.
5. The system of claim 1 , wherein the processor is further configured to map one or more portions of the footprint to a patient activity state.
6. The system of claim 1 , wherein the one or more patterns indicative of disordered breathing comprise a feature of the footprint.
7. The system of claim 1 , wherein the one or more patterns indicative of disordered breathing comprise an ectopic island of the footprint.
8. The system of claim 1 , wherein the processor analysis of the footprint comprises identification of a location of the footprint that is indicative of disordered breathing.
9. The system of claim 1 , wherein a second one of the one or more indices is representative of a shape of the footprint.
10. The system of claim 1 , wherein the processor is further configured to map one or more portions of the footprint to one or both of patient sleep and wakefulness states.
11. The system of claim 1 , wherein at least one of the one or more patterns indicative of disordered breathing is indicative of sleep disordered breathing.
12. The system of claim 1 , wherein at least one of the one or more patterns indicative of disordered breathing is indicative of dyspnea.
13. The system of claim 1 , wherein the processor assessment of the patient's health status comprises discrimination between stable and worsening heart failure status.
14. The system of claim 1 , wherein the processor is further configured to map one or more portions of the footprint to time of day.
15. The system of claim 1 , wherein the processor is further configured to map one or more portions of the footprint to patient posture.
16. The system of claim 1 , further comprising a display device, wherein the processor is configured to cause the display device to display or plot the footprint.
17. The system of claim 1 , wherein the processor is configured to perform statistical analyses of the footprint to identify the one or more patterns indicative of disordered breathing.
18. The system of claim 1 , wherein the processor is configured to perform pattern recognition analyses of the footprint to identify the one or more patterns indicative of disordered breathing.
19. The system of claim 1 , wherein the medical device is configured to deliver a therapy and the processor is configured to adjust or titrate the therapy based on the identification of the one or more patterns indicative of disordered breathing.
20. The system of claim 1 , wherein the medical device is configured to deliver a therapy and the processor is configured to one or both of determine and monitor effectiveness of the therapy based on the identification of the one or more patterns indicative of disordered breathing.
21. The system of claim 1 , wherein the output comprises an alert to a physician or patient based on the assessment of the patient's health status.
22. The system of claim 1 , wherein the one or more patterns indicative of disordered breathing comprise a contour of the footprint.
23. The system of claim 1 , wherein the processor assessment of the patient's health status comprises assessment of the patient's heart failure status based on the identification of the one or more disordered breathing patterns and the output is based on the assessment of the heart failure.
24. The system of claim 1 , wherein the processor assessment of the patient's health status comprises assessment of the patient's disordered breathing status based on the identification of the one or more disordered breathing patterns and the output is based on the assessment of the disordered breathing status.
25. The system of claim 1 , wherein the detection circuitry is further configured to detect cardiac signals representative of cardiac electrical activity and the processor is further configured to generate a cardiac activity footprint comprising a mapping having a plurality of contour lines representative of the patient's heart rate variability using the cardiac signals, combine the cardiac activity footprint with the footprint that is generated from the respiration parameter variability, develop a cardio-respiratory index using the combined footprints, and generate one or more outputs based on the cardio-respiratory index.
26. The system of claim 1 , wherein the processor is configured to assess a worsening heart failure status based on an increase in size of the one or more patterns of the footprint.
27. The system of claim 1 , wherein the processor is configured to assess a worsening disordered breathing status based on an increase in size of the one or more patterns of the footprint.
28. The system of claim 1 , wherein the processor is configured to identify at least one of the plurality of contour lines that forms an enclosed loop by itself as a pattern indicative of disordered breathing.
29. The system of claim 1 , wherein the medical device is configured for patient implantation and the detection circuitry and the processor are contained within the medical device.
30. A system, comprising:
a medical device comprising sensing circuitry;
detection circuitry coupled to the sensing circuitry, the detection circuitry configured to detect a patient respiration parameter of a patient; and
a processor coupled to the detection circuitry, the processor configured to generate a footprint comprising a mapping of a plurality of contour lines representative of the patient's respiration parameter variability using a respiration-modulated signal detected by the detection circuitry, map one or more portions of the footprint to a patient sleep state and a patient wakefulness state, analyze the footprint to identify one or more patterns indicative of disordered breathing, assess the patient's health status based on the analysis of the footprint to identify the one or more disordered breathing patterns, and generate an output based on the assessment of the patient's health status.