Temperature monitoring for sleep disordered breathing

Patent metadata

Field	Value
Publication number	US-11992306-B2
Application number	US-202117486521-A
Country	US
Kind code	B2
Filing date	Sep 27, 2021
Priority date	Sep 30, 2020
Publication date	May 28, 2024
Grant date	May 28, 2024

Abstract

Systems and methods to are disclosed to determine a sleep disordered breathing parameter of a patient, including receiving respiration information of the patient and temperature information of the patient and to determine the sleep disordered breathing parameter of the patient using the received respiration information and temperature information of the patient.

First claim

What is claimed is:

1. An implantable cardiac monitor, comprising:
a respiration sensor configured to sense respiration information of a patient;
a temperature sensor configured to sense temperature information of a housing of the implantable cardiac monitor; and
an assessment circuit configured to determine distal skin temperature of the patient using the sensed temperature information and to determine a sleep disordered breathing parameter of the patient using the sensed respiration information of the patient and the determined distal skin temperature of the patient.

2. The implantable cardiac monitor of claim 1 , wherein the respiration sensor includes an impedance sensor configured to sense an impedance of the thorax of the patient and to determine respiration information of the patient using changes in the sensed impedance associated with patient respiration,
wherein the determined respiration information includes a determined tidal volume measure of the patient, and
wherein the assessment circuit is configured to determine the sleep disordered breathing parameter using a detected decrease in the determined tidal volume measure of the patient greater than a sleep disordered breathing threshold from a baseline tidal volume measure over a detection window.

3. The implantable cardiac monitor of claim 2 , wherein
the assessment circuit is configured to determine the sleep disordered breathing parameter using a combination of determined tidal volume measure of the patient over the detection window and the determined patient distal skin temperature corresponding to the detection window.

4. The implantable cardiac monitor of claim 3 , wherein the assessment circuit is configured to determine the sleep disordered breathing parameter using the detected decrease in the determined tidal volume measure of the patient greater than the sleep disordered breathing threshold and the determined patient distal skin temperature greater than a temperature threshold,
wherein the sleep disordered breathing parameter includes an indication that a sleep disordered breathing event has occurred over the detection window, and
wherein the assessment circuit is configured to determine the baseline tidal volume measure using the determined tidal volume measure of the patient over a baseline period longer than the detection window and preceding the detection window.

5. The implantable cardiac monitor of claim 4 , wherein the detection window has a period between 5 and 15 seconds, and wherein the baseline period is a minute or longer.

6. The implantable cardiac monitor of claim 4 , wherein the assessment circuit is configured to count a number of sleep disordered breathing events in a daily period, and
wherein the assessment circuit is configured to adjust at least one of the sleep disordered breathing threshold or the length of the detection window using the sensed temperature information.

7. The implantable cardiac monitor of claim 3 , wherein the assessment circuit is configured to determine the temperature threshold using a rate of change of the sensed temperature information.

8. The implantable cardiac monitor of claim 2 , wherein the assessment circuit is configured to:
determine an initial sleep disordered breathing parameter of the patient using the sensed respiration information; and
determine a confidence indication of the determined initial sleep disordered breathing parameter using the sensed temperature information.

9. The implantable cardiac monitor of claim 8 , wherein the confidence indication includes indications of high confidence and low confidence, and
wherein the assessment circuit is configured to:
determine an indication of high confidence if the sensed temperature information corresponding to the determined initial sleep disordered breathing parameter is at or above a threshold; and
determine an indication of low confidence if the sensed temperature information corresponding to the determined initial sleep disordered breathing parameter is below the threshold.

10. A medical device system, comprising:
a signal receiver circuit configured to receive respiration information of a patient and temperature information of an implantable housing of the medical device system; and
an assessment circuit configured to determine distal skin temperature of the patient using the received temperature information and to determine a sleep disordered breathing parameter of the patient using the received respiration information and the determined distal skin temperature of the patient.

11. The medical device system of claim 10 , wherein the respiration information comprises impedance information of the patient indicative of a tidal volume of the patient, and
wherein the assessment circuit is configured to determine the sleep disordered breathing parameter using a detected decrease in the received impedance information greater than a sleep disordered breathing threshold from a baseline respiration measure over a detection window.

12. The medical device system of claim 11 , wherein
the assessment circuit is configured to determine the sleep disordered breathing parameter using a combination of the received impedance information over the detection window and the temperature of the implantable housing corresponding to the detection window.

13. The medical device system of claim 12 , wherein the assessment circuit is configured to determine the sleep disordered breathing parameter using the detected decrease in the received impedance information indicative of the tidal volume of the patient greater than the sleep disordered breathing threshold and the temperature of the implantable housing greater than a temperature threshold,
wherein the sleep disordered breathing parameter includes an indication that a sleep disordered breathing event has occurred over the detection window, and
wherein the assessment circuit is configured to determine the baseline tidal volume measure using the determined tidal volume measure of the patient over a baseline period longer than the detection window and preceding the detection window.

14. The medical device system of claim 13 , wherein the detection window has a period between 5 and 15 seconds,
wherein the baseline period is a minute or longer,
wherein the assessment circuit is configured to count a number of sleep disordered breathing events in a daily period, and
wherein the assessment circuit is configured to adjust at least one of the sleep disordered breathing threshold or the length of the detection window using the received temperature information.

15. The medical device system of claim 11 , wherein the assessment circuit is configured to:
determine an initial sleep disordered breathing parameter of the patient using the received respiration information; and
determine a confidence indication of the determined initial sleep disordered breathing parameter using the received temperature information.

16. The medical device system of claim 15 , wherein the confidence indication includes indications of high confidence and low confidence, and
wherein the assessment circuit is configured to:
determine an indication of high confidence if the received temperature information corresponding to the determined initial sleep disordered breathing parameter is at or above a threshold; and
determine an indication of low confidence if the received temperature information corresponding to the determined initial sleep disordered breathing parameter is below the threshold.

17. A method, comprising:
receiving respiration information of a patient and

Assignees

• Cardiac Pacemakers Inc

Inventors

• Wen Gezheng
• Thakur Pramodsingh Hirasingh
• Hatlestad John D
• An Qi

Classifications

• A61B5/0826 Primary

  Detecting or evaluating apnoea events (sleep apnoea A61B5/4818) · CPC title

• A61B5/01

  Measuring temperature of body parts {; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue} (clinical contact thermometers G01K13/20) · CPC title

• A61B5/085

  Measuring impedance of respiratory organs or lung elasticity · CPC title

• A61B5/091

  Measuring volume of inspired or expired gases, e.g. to determine lung capacity · CPC title

• A61B5/4806 Primary

  Sleep evaluation (A61B5/4821 takes precedence; devices for inducing sleep A61M21/02) · CPC title