System and method for generating a trend parameter based on respiration rate distribution

• US 8,372,012 B2
• Filed: 04/28/2010
• Issued: 02/12/2013
• Est. Priority Date: 09/16/2005
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Zhang, Yi, Averina, Viktoria, Dalal, Yousufali
• Primary Examiner(s): Kahelin, Michael
• Assistant Examiner(s): D'ANGELO, MICHAEL J
• Application Number:
  US12/769,020
• Publication Number:
  US 20100228133A1
• Time in Patent Office: 1,021 Days
• Field of Search: 600/484, 600/529, 600/538
• US Class Current: 600/483
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• 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 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/0803 Recording apparatus specially adapted therefor
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance
• CPC Class Codes: C07C 17/361 by reactions involving a decrease in the number of carbon atoms
• CPC Class Codes: C07C 19/16 and iodine

Abstract

Systems and methods provide for assessing the heart failure status of a patient and, more particularly, to generating a trend parameter based on a distribution of the patient'"'"'s respiration rate. Systems and methods provide for detecting, using an implantable device or a patient-external device, patient respiration and computing a respiration rate based on the detected patient respiration. A distribution of the respiration rate is calculated, and a trend parameter based on the respiration rate distribution is generated. The trend parameter is indicative of a patient'"'"'s heart failure status. An output signal indicative of the patient'"'"'s heart failure status may be generated based on the trend parameter.

Claims

1. A method, comprising:

detecting respiration of a patient over a period of time;

computing a plurality of respiration rates for the period of time based on the detected patient respiration;

calculating a distribution of the respiration rates based on the plurality of respiration rates;

determining the patient'"'"'s rapid shallow breathing (RSB) burden for the time period using the respiration rate distribution on a processor, the RSB burden characterized by rapid shallow breathing of the patient during the time period;

generating an RSB trend parameter based on the respiration rate distribution;

producing an output indicative of the patient'"'"'s heart failure status based on the patient'"'"'s RSB burden; and

predicting patient decompensation episodes using the RSB trend parameter.

2. The method of claim 1, wherein determining the patient'"'"'s RSB burden for the time period comprises computing a percentage of time that the patient experiences rapid shallow breathing during the time period.

3. The method of claim 2, wherein the time period comprises a day.

4. The method of claim 1, wherein at least detecting patient respiration comprises detecting patient respiration using an implantable device.

5. The method of claim 1, comprising titrating a patient therapy using the RSB trend parameter.

6. The method of claim 1, comprising discriminating between stable heart failure status and decompensated heart failure status of the patient using the RSB trend parameter.

7. The method of claim 1, comprising displaying one or both of data and graphs associated with one or more of the plurality of respiration rates, the respiration rate distribution, the RSB burden, and the output indicative of the patient'"'"'s heart failure status.

8. The method of claim 1, comprising generating an alert based on the output indicative of a worsening of the patient'"'"'s heart failure status.

9. The method of claim 1, comprising:

generating a histogram based on the plurality of respiration rates;

providing a measure of characteristic respiration rate for the histogram;

determining a measure of respiration rate distribution spread; and

generating an RSB trend parameter based on a relationship between the measure of characteristic respiration rate and measure of respiration rate distribution spread.

10. The method of claim 1, comprising:

generating a histogram based on the plurality of respiration rates; and

generating an RSB trend parameter based on one or more areas under a curve of the histogram relative to a respiration rate threshold.

11. A system, comprising:

a medical device coupled to sensing circuitry;

detection circuitry coupled to the sensing circuitry, the detection circuitry configured to detect at least one respiratory parameter;

a processor coupled to the detection circuitry, the processor configured to compute a plurality of respiration rates for a period of time based on the detected respiratory parameter, calculate a distribution of the respiration rates based on the plurality of respiration rates, determine the patient'"'"'s rapid shallow breathing (RSB) burden for the time period using the respiration rate distribution, the RSB burden characterized by rapid shallow breathing of the patient during the time period, generate an RSB trend parameter based on the respiration rate distribution, and predict patient decompensation episodes using the RSB trend parameter; and

an output coupled to the processor and configured to produce an output signal indicative of the patient'"'"'s heart failure status based on the patient'"'"'s RSB burden.

12. The system of claim 11, wherein the medical device comprises a patient implantable medical device.

13. The system of claim 11, wherein the processor comprises a processor of a networked patient management system.

14. The system of claim 11, wherein the processor comprises a processor of a programmer or a portable communicator.

15. The system of claim 11, wherein the sensing circuitry comprises at least one of a transthoracic impedance sensor, a minute ventilation sensor, an accelerometer, and a pressure sensor.

16. The system of claim 11, wherein the processor is configured to execute program instructions for at least one of:

titrating a patient therapy using the RSB trend parameter; and

discriminating between stable heart failure status and decompensated heart failure status of the patient using the RSB trend parameter.

17. The system of claim 11, comprising a display coupled to the output and configured to display one or both of data and graphs associated with one or more of the plurality of respiration rates, the respiration rate distribution, the RSB burden, and the output indicative of the patient'"'"'s heart failure status.

18. The system of claim 11, wherein the processor is configured to generate an alert based on the output indicative of a worsening of the patient'"'"'s heart failure status.

19. The system of claim 11, wherein the processor is configured to execute program instructions for:

generating a histogram based on the plurality of respiration rates;

providing a measure of characteristic respiration rate for the histogram;

determining a measure of respiration rate distribution spread; and

generating an RSB trend parameter based on a relationship between the measure of characteristic respiration rate and measure of respiration rate distribution spread.

20. The system of claim 11, wherein the processor is configured to execute program instructions for:

generating a histogram based on the plurality of respiration rates; and

generating an RSB trend parameter based on one or more areas under a curve of the histogram relative to a respiration rate threshold.