Sleep detection using an adjustable threshold

• US 8,956,295 B2
• Filed: 09/09/2013
• Issued: 02/17/2015
• Est. Priority Date: 12/04/2002
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Ni, Quan, Hajenga, Zoe, Daum, Douglas R., Stahmann, Jeffrey E., Hatlestad, John D., Lee, Kent
• Primary Examiner(s): Thomson, William
• Assistant Examiner(s): ARCHER, MARIE
• Application Number:
  US14/021,773
• Publication Number:
  US 20140005503A1
• Time in Patent Office: 526 Days
• Field of Search: 600300-301, 600/595, 600/484, 600/324, 600/483, 600/508, 600529-533, 607/9, 607 17- 19, 706 46- 47, 702/19, 340/575
• US Class Current: 600/301
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• 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 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/085 Measuring impedance of respiratory organs or lung elasticity
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/4809 Sleep detection, i.e. determining whether a subject is asleep or not
• CPC Class Codes: A61B 5/4815 Sleep quality
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61B 5/7271 Specific aspects of physiological measurement analysis A61B5/316, A61B5/349 and A61B5/374 take precedence
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61N 1/362 Heart stimulators heart defibrillators A61N1/39
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

Devices and methods for sleep detection involve the use of an adjustable threshold for detecting sleep onset and termination. A method for detecting sleep includes adjusting a sleep threshold associated with a first sleep-related signal using a second sleep-related signal. The first sleep-related signal is compared to the adjusted threshold and sleep is detected based on the comparison. The sleep-related signals may be derived from implantable or external sensors. Additional sleep-related signals may be used to confirm the sleep condition. A sleep detector device implementing a sleep detection method may be a component of an implantable pulse generator such as a pacemaker or defibrillator.

Claims

1. A method of detecting sleep, comprising:

sensing a plurality of sleep-related signals;

storing a relationship that relates sleep detection to the plurality of sleep-related signals, wherein the relationship evaluates a second one of the plurality of the sleep-related signals as a function of a first one of the plurality of the sleep-related signals;

detecting sleep based on the sensed plurality of sleep-related signals in conjunction with the stored relationship; and

providing an output signal indicative of an outcome of the sleep detection;

wherein at least one of storing, detecting and providing is performed at least in part implantably and effectuated at least in part by a processor.

2. The method of claim 1, further comprising:

transmitting the output signal to another device capable of operating responsively to the output signal.

3. The method of claim 1, further comprising establishing the relationship.

4. The method of claim 3, wherein the relationship is established based on clinical data.

5. The method of claim 3, wherein the relationship is established based on patient data.

6. The method of claim 1, wherein the plurality of sleep-related signals include at least two of a cardiac signal, a respiratory signal, and a patient activity signal.

7. The method of claim 6, wherein the patient activity signal comprises an acceleration signal from an accelerometer.

8. The method of claim 6, wherein the respiration signal comprises a minute ventilation signal from a minute ventilation sensor.

9. The method of claim 6, wherein the cardiac signal is indicative of heart rate.

10. The method of claim 1, wherein the dependence comprises an interrelationship between the first one of the plurality of the sleep-related signals and the second one of the plurality of the sleep-related signals.

11. The method of claim 10, where the relationship includes a threshold for the first one of the plurality of the sleep-related signals, wherein the first one of the plurality of the sleep-related signals is compared to the threshold, and wherein the interrelationship comprises the second one of the plurality of the sleep-related signals influencing the threshold.

12. A sleep detection device, comprising:

sensors configured to sense a plurality of sleep-related signals; and

an implantable sleep processor coupled to the sensors, the implantable sleep processor storing a relationship that relates sleep detection to the plurality of sleep-related signals, wherein the relationship defines an inverse relationship between a first one of the plurality of the sleep-related signals and a second one of the plurality of the sleep-related signals, the implantable sleep processor configured to detect sleep based on the sensed plurality of sleep-related signals in conjunction with the stored relationship, and to provide an output signal indicative of an outcome of the sleep detection.

13. The sleep detection device of claim 12, further comprising an output for outputting the output signal to another device capable of operating responsively to the output signal.

14. The device of claim 12, wherein the sensors comprise an accelerometer configured to sense patient activity and transthoracic impedance sensor configured to sense respiration.

15. The device of claim 12, wherein at least one of the sensors is external to the patient.

16. The device of claim 12, wherein the sleep processor is a component of an implantable cardiac therapy device.

17. The method of claim 12, wherein the dependence comprises an interrelationship between the first one of the plurality of the sleep-related signals and the second one of the plurality of the sleep-related signals.

18. The method of claim 17, where the relationship includes a threshold for the first one of the plurality of the sleep-related signals, wherein the first one of the plurality of the sleep-related signals is compared to the threshold, and wherein the interrelationship comprises the second one of the plurality of the sleep-related signals influencing the threshold.

19. A sleep detection device, comprising:

an accelerometer configured to sense a measure related to patient activity;

a transthoracic impedance sensor configured to sense a measure related to respiration;

a heart rate sensor configured to sense a measure related to heart rate;

the measure related to patient activity, the measure related to respiration and the measure related to heart rate comprising sleep-related signals; and

an implantable sleep processor coupled to the sensors, the implantable sleep processor storing a relationship that relates sleep detection to at least two of the sleep-related signals, wherein the relationship evaluates a second one of the sleep-related signals as a function of a first one of the plurality of the sleep-related signals, wherein the implantable sleep processor is configured to detect sleep based on the sensed sleep-related signals in conjunction with the stored relationship, and to provide an output signal indicative of an outcome of the sleep detection.

20. The sleep detection device of claim 19, further comprising an output for outputting the output signal to another device capable of operating responsively to the output signal.