System and method for mapping diaphragm electrode sites

• US 20050085869A1
• Filed: 10/15/2004
• Published: 04/21/2005
• Est. Priority Date: 10/15/2003
• Status: Abandoned Application

• Current Assignee: RMX, LLC (ASHINC Corp.)
• Original Assignee: RMX, LLC (ASHINC Corp.)
• Inventors: Ligon, David, Mo, Anthony, Meltzer, Mark, Lee, Chang, Tehrani, Amir J.
• Application Number:
  US10/966,484
• Publication Number:
  US 20050085869A1
• Time in Patent Office: Days
• US Class Current: 607/42
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/389 Electromyography [EMG]
• CPC Class Codes: A61B 5/395 Details of stimulation, e.g. nerve stimulation to elicit EMG response
• CPC Class Codes: A61B 5/4818 Sleep apnoea
• 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: A61N 1/3601 of respiratory organs
• CPC Class Codes: A61N 1/36132 using patient feedback

Abstract

A signal source coupled to one or more electrodes in the vicinity of the diaphragm for mapping therapeutic electrode sites. A stimulus signal from the signal source may be applied to the one or more electrodes to produce activation of the diaphragm. Activation of the diaphragm is sensed to provide information that may be correlated with the stimulus signal. The correlated information may be used to identify a therapeutic locus for a therapeutic electrode. An electrical stimulus comprising a series of pulses may be applied to the one or more electrodes to elicit a desired breathing response. The electrical stimulus may be applied between intrinsic breathing cycles, or between regulated breathing cycles. More than one electrode may be supported on a single substrate. The substrate may configured to be positioned on the diaphragm. A hierarchy of stimuli may be applied to a set of electrodes.

Claims

1. A system for mapping therapeutic electrode sites on a diaphragm comprising:

a signal source configured to provide a stimulus for eliciting a respiration response comprising an inspiration waveform having a morphology;

one or more implanted electrodes coupled to the signal source and configured to deliver the stimulus to body tissue within the body.

a sensor configured to sense a parameter corresponding to the respiration response; and

,

a processor coupled to the sensor, configured to receive a signal from the sensor corresponding to the respiration response, and configured to determine a correlation between the morphology and a desired morphology.

2. The system for mapping therapeutic electrode sites of claim 1 wherein the desired morphology comprises a natural breathing pattern.

3. The system for mapping therapeutic electrode sites of claim 1 wherein the desired morphology is configured to elicit a desired physiological response.

4. The system for mapping therapeutic electrodes sites of claim 3 wherein the desired physiological response is to influence SaO2 levels.

5. The system for mapping therapeutic electrodes sites of claim 3 wherein the desired physiological response is to influence PCO2 levels.

6. The system for mapping therapeutic electrode sites on a diaphragm of claim 1 wherein the electrodes are coupled to a substrate.

7. The system for mapping therapeutic electrode sites on a diaphragm of claim 6 wherein the sensor is coupled to the substrate.

8. The system for mapping therapeutic electrode sites on a diaphragm of claim 1 wherein the waveform comprises information representative of inter-abdominal pressure over time.

9. The system for mapping therapeutic electrode sites on a diaphragm of claim 1 wherein the waveform comprises information representative of thoracic pressure over time.

10. The system for mapping therapeutic electrode sites on a diaphragm of claim 1 wherein the waveform comprises information representative of movement of the diaphragm over time.

11. The system for mapping therapeutic electrode sites on a diaphragm of claim 1 wherein the waveform comprises information representative of at least a portion of a diaphragm EMG over time.

12. The system for mapping therapeutic electrode sites on a diaphragm of claim 1 wherein the waveform comprises information representative of airway flow over time.

13. A system for mapping therapeutic electrode sites on a diaphragm comprising:

a signal source configured to provide a stimulus configured to elicit a respiration response;

one or more electrodes coupled to the signal source and configured to deliver the stimulus to tissue of a body;

a sensor configured to sense a response to the stimulus wherein the sensor is configured to sense at least one parameter corresponding the respiration response; and

,

a processor coupled to the sensor and configured to receive a signal corresponding to the at least one parameter, wherein the processor is configured to determine from the at least one parameter, a ratio of a portion of peak volume over a portion of stimulation time.

14. The system of claim 13 wherein the processor is configured to determine whether the percentage of peak volume per percentage of and inspiration cycle corresponds to an acceptable respiration response.

15. The system of claim 14 wherein the acceptable response is a ratio of less than or equal to about 10.

16. The system of claim 15 wherein the acceptable response is a ratio of less than or equal to about 3.5.

17. A system for mapping therapeutic electrode sites on a diaphragm comprising:

a signal source configured to provide a stimulus configured to elicit a respiration response;

one or more electrodes coupled to the signal source and configured to deliver the stimulus to tissue of a body;

a sensor configured to sense a response to the stimulus wherein the sensor is configured to sense at least one parameter corresponding the respiration response; and

,

a processor coupled to the sensor and configured to receive a signal corresponding to the at least one parameter, wherein the processor is configured to determine from the at least one parameter whether a sustained inspiration portion of a stimulation duration for a cycle is at an acceptable level.

18. The system of claim 17 wherein an acceptable level is about 0.5 of the stimulation duration or more.

19. The system of claim 17 wherein an acceptable level is about 0.75 of the stimulation duration or more.

20. A system for mapping therapeutic electrode sites on a diaphragm comprising:

a signal source configured to provide a stimulus configured to elicit a respiration response;

one or more electrodes coupled to the signal source and configured to deliver the stimulus to tissue of a body;

a sensor configured to sense a response to the stimulus wherein the sensor is configured to sense at least one parameter corresponding the respiration response; and

,

a processor coupled to the sensor and configured to receive a signal corresponding to the at least one parameter, wherein the processor is configured to determine from the at least one parameter whether an instantaneous slope of peak flow over stimulation time is at an acceptable level.

21. The system of claim 20 wherein an acceptable level of instantaneous slope of peak flow over stimulation time is about 2 or less.

22. The system of claim 20 wherein an acceptable level of the instantaneous slope of peak flow over stimulation time is about 0.75 or less.

23. A system for mapping therapeutic electrode sites on a diaphragm comprising:

a signal source configured to provide a stimulus configured to elicit a respiration response;

one or more electrodes coupled to the signal source and configured to deliver the stimulus to tissue of a body;

a sensor configured to sense a response to the stimulus wherein the sensor is configured to sense at least one parameter corresponding the respiration response; and

,

a processor coupled to the sensor and configured to receive a signal corresponding to the at least one parameter, wherein the processor is configured to determine from the at least one parameter whether an instantaneous slope of peak flow over stimulation time is at an acceptable level.

24. The system of claim 23 wherein an acceptable level of minimum time to reach peak flow between about 100 milliseconds and 300 milliseconds.

25. The system of claim 23 wherein an acceptable level of minimum time to reach peak flow is greater than or equal to about 300 milliseconds.

26. An electrode assembly comprising:

an inflatable member comprising a substrate and an inflation chamber configured to receive an inflation medium; and

one or more electrodes configured to deliver or sense an electrical signal, coupled to the substrate.

27. The electrode assembly of claim 26 wherein the assembly is configured to be positioned on a diaphragm.

28. The electrode assembly of claim 26 further comprising a manipulation member coupled to the inflatable member, wherein the manipulation member is configured to position the inflatable member in a desired location adjacent a portion of a body.

29. An electrode assembly for stimulating sites on a diaphragm comprising:

a member configured to be positioned on a diaphragm during electrical stimulation of the diaphragm; and

,

a plurality of electrodes coupled to the member and configured to deliver electrical stimulation to the diaphragm.

30. The electrode assembly of claim 29 wherein the member comprises a keyed portion configured to be positioned adjacent an anatomical structure of the diaphragm to aid in positioning of the member.

31. The electrode assembly of claim 29 wherein the member comprises a flexible portion configured to accommodate movement of the diaphragm during electrical stimulation.

32. The electrode assembly of claim 29 wherein the member comprises a perimeter having a shape that conforms to a specific feature on a surface of a diaphragm.

33. The electrode assembly of claim 29 wherein the member comprises an active surface configured to interface with a diaphragm surface, wherein the plurality of electrodes is coupled to the active surface of the member, and wherein the active surface is curved.

34. The electrode assembly of claim 29 wherein at least one of the plurality of electrodes comprises a subsurface electrode.

35. The electrode assembly of claim 29 wherein at least one of the plurality of electrodes comprises a composite electrode.

36. The electrode assembly of claim 29 further comprising a switching network coupled to the plurality of electrodes.

37. The electrode assembly of claim 29 wherein the member comprises a mesh.

38. A method for delivering an electrode array to a diaphragm comprising the steps of:

providing an electrode array configured to be compressed to a first configuration and to expand to a second configuration;

compressing the electrode array to the first configuration;

positioning the electrode array adjacent a diaphragm within a subject'"'"'s body; and

expanding the electrode array to the second configuration.

39. The method of claim 38 wherein the step of compressing the electrode array comprises folding the electrode array;

and wherein the step of expanding the electrode array comprises unfolding the electrode array.

40. The method of claim 38 wherein the step of expanding the electrode array comprises inflating the electrode array.

41. The method of claim 40 further comprising calculating intrinsic breathing parameters and establishing a target response.

42. The method of claim 41 further comprising comparing the response to the target response.

43. The method of claim 42 further comprising the step of determining whether the response sufficiently correlates with the target response.

44. The method of claim 40 wherein the stimulus is applied asynchronously.

45. The method of claim 40 wherein the stimulus is applied synchronously.

46. The method of claim 40 wherein the stimulus is applied between intrinsic breathing cycles.

40-1. A method for mapping electrode sites on a diaphragm, the method comprising:

placing a mapping electrode array on a surface of the diaphragm;

sensing and recording an intrinsic breathing pattern;

selecting an electrode of the mapping electrode array;

delivering a stimulus wave to the electrode; and

,

sensing and recording a response to the stimulus wave.

47. A method for mapping electrode sites on a diaphragm, the method comprising:

placing a mapping electrode array on a surface of the diaphragm;

selecting an electrode of the mapping electrode array;

delivering a stimulus to the selected electrode; and

,

sensing and recording a response to the stimulus.

48. The method of claim 47 further comprising the step of:

defining an acceptable breathing response morphology.

49. The method of claim 48 further comprising the step of comparing the recorded response to the acceptable breathing response morphology.

50. The method of claim 49 further comprising the step of determining whether the response is sufficiently close to the desired breathing response morphology.

51. A system for electrically stimulating a diaphragm comprising:

an implantable electrode configured to be positioned on the diaphragm;

a signal source configured to provide a stimulation signal to the diaphragm through the electrodes, wherein the stimulation signal comprises a series of pulses that vary in amplitude.

52. The system of claim 51 wherein the pulses vary in frequency.

53. A system for electrically stimulating a diaphragm comprising:

an implantable electrode configured to be positioned on the diaphragm;

a signal source configured to provide a stimulation signal to the diaphragm through the electrodes, wherein the stimulation signal comprises a series of pulses that vary in frequency.