Devices and methods for vagus nerve stimulation

• US 7,072,720 B2
• Filed: 06/14/2002
• Issued: 07/04/2006
• Est. Priority Date: 06/25/1999
• Status: Active Grant

• Current Assignee: Emory University
• Original Assignee: Emory University
• Inventors: Puskas, John D.
• Primary Examiner(s): Manuel, George
• Assistant Examiner(s): Greene, Dana D.
• Application Number:
  US10/172,377
• Publication Number:
  US 20030074039A1
• Time in Patent Office: 1,481 Days
• Field of Search: 607/118, 607/5, 607/9, 607/149
• US Class Current: 607/118
• CPC Class Codes: A61N 1/0517 Esophageal electrodes
• CPC Class Codes: A61N 1/0519 Endotracheal electrodes
• CPC Class Codes: A61N 1/0526 Head electrodes A61N1/0551 takes precedence
• CPC Class Codes: A61N 1/0556 Cuff electrodes
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/36185 Selection of the electrode configuration
• CPC Class Codes: A61N 1/3686 configured for selecting the electrode configuration on a lead A61N1/3688 takes precedence

Abstract

The present invention relates to apparatus and methods for electrically inducing and pharmacologically maintaining cardiac asystole. The present invention combines electrostimulation of the vagus nerve to transiently arrest the heart, and the administration of a pharmaceutical composition that suppresses the tendency of the heart to escape from the induced asystolic state. The present invention provides an apparatus to interrogate the response of a heart to an electric pulse applied to the vagus nerve and to select the optimum location of an electrode and pulse to arrest the heart. The present invention further provides embodiments of catheter and tube electrode devices that incorporate expanding electrodes intended to contact the interior walls of blood vessels or anatomic structures in which the electrode devices are implanted. The present invention also provides cutaneous array electrodes that may be used non-invasively to stimulate the vagus nerve.

Claims

1. A device for electrically stimulating the vagus nerve of a patient, comprising:

an elongated body member of sufficient length to extend from a point outside of a patient to a location within one of the trachea, esophagus, and internal jugular vein of said patient, said elongated body member having a proximal end and a distal end, said body member having an outer diameter adjacent said distal end of said body member smaller than the inner diameter of said one of said trachea, said esophagus, and said internal jugular vein;

an expandable support member adjacent said distal end of said body member, said expandable support member normally being contracted to an outer diameter smaller than the inner diameter of said one of said trachea, said esophagus, and said internal jugular vein, and said expandable support member being selectively expandable when said distal end of said body member is inserted into said one of said trachea, said esophagus, and said internal jugular vein to contact the wall of said one of said trachea, said esophagus, and said internal jugular vein around substantially the entire circumference of said expandable support member; and

an electrode mounted on said expandable support member, at least a portion of said electrode being disposed on said portion of said expandable support member that contacts said wall of said one of said trachea, said esophagus, and said internal jugular vein when said expandable support member is inserted into said one of said trachea, said esophagus, and said internal jugular vein and expanded; and

means for placing said electrode in conductive communication with a source of electrical energy so as to energize said electrode;

whereby when said distal end of said body member is inserted into said one of said trachea, said esophagus, and said internal jugular vein, and said expandable support member is expanded, said electrode is firmly imposed against said wall of said one of said trachea, said esophagus, and said internal jugular vein.

2. The device of claim 1,

wherein said elongated body member is dimensioned for use in the esophagus, and

wherein said device further comprises a hollow internal lumen extending from a proximal opening at a proximal portion of said elongated body member to a distal opening at a distal portion of said elongated body member;

whereby liquid and gas can be suctioned from the stomach and esophagus through said lumen so as to decompress the gastrointestinal tract, and

whereby medications can be enterally administered through said lumen.

3. The device of claim 1,

wherein said elongated body member is dimensioned for use in the trachea, and

wherein said device further comprises a hollow internal lumen extending from a proximal opening at a proximal portion of said elongated body member to a distal opening at a distal portion of said elongated body member;

whereby said device serves to maintain an airway during anesthesia, allowing positive-pressure ventilation of the patient'"'"'s lungs.

4. The device of claim 3, further comprising an inflatable balloon cuff located on a distal portion of said elongated body member, said balloon cuff being inflatable and deflatable via a second lumen extending from a proximal portion of said elongated body member to a location inside said balloon cuff.

5. The device of claim 1,

wherein said elongated body member is dimensioned for use in an internal jugular vein, and wherein said device further comprises a hollow central lumen extending from a proximal opening at a proximal portion of said elongated body member to a distal opening at a distal portion of said elongated body member, through which intravenous liquids and medications can be administered to a patient.

6. The device of claim 1,

wherein said elongated body member is dimensioned for use in said internal jugular vein, and wherein said device further comprises:

a hollow channel in said elongated body member, said channel being in fluid communication with the ambient through a hole in the side of and proximal to the distal end of said elongated body member,

whereby central venous pressure can be monitored through said hollow channel.

7. The device of claim 1,

wherein said elongated body member is dimensioned for use in the internal jugular vein, and wherein said device further comprises:

an inflatable balloon located on a distal portion of said elongated body member; and

means at said distal end of said elongated body member for monitoring pulmonary artery pressures.

8. The device of claim 1,

wherein said expandable support member comprises an inflatable cuff, and

wherein said expandable support member is selectively expandable by inflating said cuff.

9. The device of claim 8,

wherein said inflatable cuff comprises at least one raised ridge which engages said wall of said one of said trachea, esophagus, and internal jugular vein when inserted therein and expanded, said raised ridge permitting fluid to flow past said inflatable cuff;

and

wherein at least a portion of said electrode is mounted on said raised ridge,

whereby said raised ridge presses said electrode against said wall of said one of said trachea, esophagus, and internal jugular vein to facilitate an optimal electrical contact.

10. The device of claim 9,

wherein said elongated body member is dimensioned to be received within said internal jugular vein, and

wherein said raised ridges define at least one flow path between a distal end of said inflatable cuff and a proximal end thereof,

whereby blood in an internal jugular vein flows past said inflatable cuff, such that inflation of said inflatable cuff within said internal jugular vein does not block venous drainage from the head.

11. The device of claim 9, wherein said raised ridge is longitudinally oriented with respect to said inflatable cuff.

12. The device of claim 9, wherein said raised ridge is circumferentially oriented with respect to said inflatable cuff.

13. The device of claim 9, wherein said raised ridge is helically oriented with respect to said inflatable cuff.

14. The device of claim 8, wherein said electrode comprises an expandable wire mesh that covers at least a portion of said inflatable cuff and which expands as said cuff is inflated.

15. The device of claim 8, wherein said electrode comprises a metal foil disposed on said inflatable cuff.

16. The device of claim 8, wherein said electrodes are maintained on said inflatable cuff by a non-conductive yoke.

17. The device of claim 1, further comprising a plurality of electrodes spaced around the circumference of said expandable support member.

18. The device of claim 17, wherein said plurality of electrodes comprises from 2 to 50 electrodes.

19. The device of claim 17, wherein said plurality of electrodes comprises from 2 to 24 electrodes.

20. The device of claim 17, wherein each of said plurality of electrodes is electrically isolated from and capable of being electrically energized independently of the others of said plurality of electrodes.

21. The device of claim 17,

wherein each of said plurality of electrodes is electrically insulated along its entire length and circumference except for at least one uninsulated portion over the exterior aspect of the middle portion of each electrode adjacent the middle portion of said inflatable cuff,

whereby said at least one uninsulated portion contacts the interior of the wall of said trachea, esophagus or internal jugular vein when said stimulation device is appropriately positioned inside a patient and said wire frame is expanded.

22. The device of claim 17, wherein said plurality of electrodes are substantially longitudinally oriented with respect to said support member.

23. The device of claim 17, wherein said plurality of electrodes are substantially circumferentially oriented with respect to said support member.

24. The device of claim 1, wherein said electrode is substantially longitudinally oriented with respect to said support member.

25. The device of claim 1, wherein said electrode is substantially circumferentially oriented with respect to said support member.

26. The device of claim 1, wherein said electrode is substantially helically oriented with respect to said support member.

27. The device of claim 1, wherein said plurality of electrodes are substantially helically oriented with respect to said support member.

28. The device of claim 1, wherein said expandable support member comprises a plurality of ribs connected to said elongated body member so as to form an expandable frame.

29. The device of claim 28, wherein said expandable frame comprises at least one rib which is substantially longitudinally oriented with respect to said elongated body member.

30. The device of claim 28, wherein said expandable frame comprises at least one rib which is substantially circumferentially oriented with respect to said elongated body member.

31. The device of claim 28, wherein said expandable frame comprises at least one rib which is substantially helically oriented with respect to said elongated body member.

32. The device of claim 28, wherein said electrode is mounted to and follows at least a portion of a rib of said expandable frame.

33. The device of claim 32, wherein said rib which said electrode follows is comprised of an electrically insulated material.

34. The device of claim 28, wherein said ribs forming said expandable frame are comprised of an electrically insulating material.

35. The device of claim 34, wherein said electrode comprises a metal foil disposed on said expandable frame.

36. The device of claim 34, further comprising a plurality of electrodes spaced around the circumference of said expandable support member.

37. The device of claim 36, wherein said plurality of electrodes comprises from 2 to 50 electrodes.

38. The device of claim 36, wherein said plurality of electrodes comprises from 2 to 24 electrodes.

39. The device of claim 36, wherein each of said plurality of electrodes is electrically isolated from and capable of being electrically energized independently of the others of said plurality of electrodes.

40. The device of claim 34, wherein said electrode comprises a wire mesh disposed on said expandable frame.

41. The device of claim 28,

wherein said expandable frame comprises a forward portion, a rearward portion, and an intermediate portion;

wherein said device further comprises a first elongated member mechanically linked to said forward portion of said frame;

wherein said device further comprises a second elongated member mechanically linked to said rearward portion of said frame; and

wherein said first and second elongated members are longitudinally movable with respect to one another so as to draw said forward and rearward portions of said frame toward one another so as to cause said intermediate portion of said frame to bow outward.

42. The device of claim 28,

wherein a plurality of said ribs are mechanically linked at their forward ends;

wherein said device further comprises an elongated member longitudinally displaceable with respect to said forward ends of said ribs; and

wherein said device further comprises a plurality of struts, one end of each of said struts being mechanically attached to said elongated member and the opposite end of each of said struts being attached to a corresponding one of said ribs,

said struts, said ribs, and said longitudinal member being configured such that extending said longitudinal member causes said struts to displace said ribs radially outward.

43. The device of claim 1,

wherein said elongated body member further comprises a lumen extending from said proximal end to said distal end;

wherein said device further comprises an elongated shaft slidably disposed within said lumen, said elongated shaft having a proximal end and a distal end, and said shaft having a length greater than the length of said elongated body member,

wherein said expandable support member comprises;

a plurality of ribs each having an inner end pivotably connected to one of said distal end of said elongated body member and said distal end of said shaft,

a plurality of struts each having an inner end pivotably connected to the other of said distal end of said elongated body member and said distal end of said shaft,

an outer portion of each of said plurality of struts being pivotably connected to an outer portion of a corresponding one of said plurality of ribs,

whereby retracting said shaft relative to said elongated body member so as to bring said distal end of said shaft closer to said distal end of said body member causes said struts to displace said outer ends of said ribs radially outward; and

wherein said electrode mounted on said expandable support member comprises said electrode being operatively associated with an outer portion of one of said ribs;

whereby retracting said longitudinal member brings said electrode into contact with the wall of said one of said trachea, esophagus, and internal jugular vein.

44. The device of claim 43, wherein said inner ends of said plurality of ribs are pivotably connected to said distal end of said elongated body member, and wherein said inner ends of said plurality of struts are pivotably connected to said distal end of said shaft.

45. The device of claim 43, wherein said inner ends of said plurality of ribs are pivotably connected to said distal end of said shaft, and wherein said inner ends of said plurality of struts are pivotably connected to said distal end of said elongated body member.

46. The device of claim 43, wherein said means for placing said electrode in conductive communication with a source of electrical energy comprises an electrical wire extending through said lumen in said elongated body member and being connected to said electrode on said outer portion of one of said plurality of ribs.

47. A device for electrically stimulating the vagus nerve of a patient, comprising:

an elongated body member having a proximal end and a distal end, said elongated body member being of sufficient length to extend from a point outside of a patient to a location within one of the trachea, esophagus, and internal jugular vein of said patient and having a diameter adjacent a forward end of said body member sufficiently small so as not to contact the entire wall of said one of said trachea, esophagus, and internal jugular vein when inserted therein;

a normally expanded, selectively contractible support member adjacent said distal end of said body member;

said support member in its normally expanded configuration having an outer circumference sufficient to contact substantially the entire inner circumference of said one of said trachea, said esophagus, and said internal jugular vein when said distal end of said body member is positioned within said one of said trachea, said esophagus, and said internal jugular vein;

said support member being selectively contractible when said distal end of said body member is inserted into said one of said trachea, said esophagus, and said internal jugular vein so as not to contact the entire wall of said one of said trachea, said esophagus, and said internal jugular vein;

means operatively associated with said support member and operable from outside said patient for selectively contracting said support member and for permitting said support member to return to its normal, expanded configuration;

an electrode mounted on said support member, at least a portion of said electrode being disposed on a portion of said support member that contacts said wall of said one of said trachea, said esophagus, and said internal jugular vein when said support member is inserted into said one of said trachea, said esophagus, and said internal jugular vein and permitted to expand to its normal configuration; and

means for placing said electrode in conductive communication with a source of electrical energy so as to energize said electrode;

whereby when said support member is contracted and said distal end of said body member is inserted into said one of the trachea or esophagus or internal jugular vein and said electrode support section is then permitted to expand to its normal configuration, said electrode is firmly imposed against said wall of said one of the trachea or esophagus or internal jugular vein.

48. The device of claim 47, wherein said means operatively associated with said support member and operable from outside said patient for selectively contracting said support member and for permitting said support member to return to its normal, expanded configuration comprises a tube positionable around said support member to contract said support member and to retain said support member in a contracted condition, said tube being selectively displaceable with respect to said support member from a location outside said patient to uncover said support member so as to permit said support member to expand to its normal configuration.

49. The device of claim 47, wherein said support member comprises a plurality of resilient ribs connected to said elongated body member so as to form a normally expanded, selectively contractible support frame.

50. The device of claim 49, wherein said support frame comprises at least one rib which is substantially circumferentially oriented with respect to said elongated body member.

51. The device of claim 49, wherein said support frame comprises at least one rib which is substantially helically oriented with respect to said elongated body member.

52. The device of claim 49, wherein said electrode is mounted to and follows at least a portion of a rib of said support frame.

53. The device of claim 52, wherein said rib which said electrode follows is comprised of an electrically insulated material.

54. The device of claim 49, wherein said ribs forming said expandable frame are comprised of an electrically insulating material.

55. The device of claim 49, further comprising a plurality of electrodes spaced around the circumference of said support member.

56. The device of claim 55, wherein said plurality of electrodes comprises from two to fifty electrodes.

57. The device of claim 55, wherein said plurality of electrodes comprises from two to twenty-four electrodes.

58. The device of claim 55, wherein each of said plurality of electrodes is electrically isolated from and capable of being electrically energized independently of the others of said plurality of electrodes.

59. The device of claim 49, wherein said resilient ribs are comprised of a shape memory metal.

60. The device of claim 49, wherein shape memory metal is electrically insulated.

61. A device for electrically stimulating the vagus nerve of a patient, comprising:

an elongated body member of sufficient length to extend from a point outside of a patient to a location within one of the trachea, esophagus, and internal jugular vein of said patient and having an outer diameter adjacent a forward end of said body member smaller than the inner diameter of said one of said trachea, said esophagus, and said internal jugular vein;

an expandable frame adjacent a distal end of said body member, said expandable frame normally being contracted to an outer diameter smaller than the inner diameter of said one of said trachea, said esophagus, and said internal jugular vein, and said expandable frame being selectively expandable when said forward end of said body member is inserted into said one of said trachea, said esophagus, and said internal jugular vein to contact the wall of said one of said trachea, said esophagus, and said internal jugular vein around substantially the entire circumference of said expandable wire frame;

said expandable frame being formed from at least one wire which is electrically uninsulated at a location which contacts the wall of said one of said trachea, said esophagus, and said internal jugular vein when said forward end of said body member is inserted into said one of said trachea, said esophagus, and said internal jugular vein and expanded to contact the wall of said one of said trachea, said esophagus, and said internal jugular vein, and

means for placing said electrode in conductive communication with a source of electrical energy so as to energize said electrode.

62. The device of claim 61, wherein said expandable frame comprises a plurality of wires.

63. The device of claim 62, wherein each of said plurality of wires of said wire frame is electrically insulated and isolated from the others of said plurality of wires, and wherein each of said plurality of wires can be individually electrically energized independently from the others of said plurality of wires.

64. The device of claim 62, wherein each wire of said wire frame is electrically insulated over its entire length and circumference except along the exterior aspect of a central portion of each wire where it contacts the interior of the wall of said one of said trachea, esophagus, and internal jugular vein when said stimulation device is appropriately positioned inside a patient and said wire frame is expanded.

65. The device of claim 61, wherein said at least one wire is substantially longitudinally oriented with respect to said elongated body member.

66. The device of claim 61, wherein said at least one wire is substantially circumferentially oriented with respect to said elongated body member.

67. The device of claim 61, wherein said at least one wire is substantially helically oriented with respect to said elongated body member.

68. The device of claim 61,

wherein said expandable wire frame comprises a forward portion, a rearward portion, and an intermediate portion;

wherein said device further comprises a first elongated member linked to said forward portion of said wire frame;

wherein said device further comprises a second elongated member linked to said rearward portion of said wire frame; and

wherein said first and second elongated members are longitudinally movable with respect to one another so as to draw said forward and rearward portions of said wire frame toward one another so as to cause said intermediate portion of said wire frame to bow outward.

69. The device of claim 61,

wherein said expandable wire frame comprises a plurality of wires linked at their forward ends;

wherein said device further comprises an elongated member longitudinally displaceable with respect to said forward ends of said wires; and

wherein said device further comprises a plurality of struts, one end of each of said struts being attached to said elongated member and the opposite end of each of said struts being attached to a corresponding one of said wires,

said struts, said wires, and said longitudinal member being configured such that extending said longitudinal member causes said struts to displace said wires radially outward.

70. The device of claim 61,

wherein said expandable wire frame comprises a plurality of wires linked at their rearward ends;

wherein said device further comprises an elongated member longitudinally displaceable with respect to said rearward ends of said wires; and

wherein said device further comprises a plurality of struts, one end of each of said struts being attached to said elongated member and the opposite end of each of said struts being attached to a corresponding one of said wires,

said struts, said wires, and said longitudinal member being configured such that retracting said longitudinal member causes said struts to displace said ribs radially outward.

71. A device for electrically stimulating the vagus nerve of a patient, comprising:

an elongated body member of sufficient length to extend from a point outside of a patient to a location within one of the trachea, esophagus, and internal jugular vein of said patient and having a diameter adjacent a forward end of said body member sufficiently small so as not to contact the entire wall of said one of the trachea, esophagus, and internal jugular vein when inserted therein;

a normally expanded, selectively contractible wire frame adjacent a forward end of said body member, said wire frame being formed from at least one wire, said wire frame in a contracted state having a diameter adjacent a forward end of said body member sufficiently small so as not to contact the entire wall of said one of the trachea, esophagus, and internal jugular vein when inserted therein, and said wire frame being configured such that when said forward end of said body member is inserted into said one of the trachea or esophagus or internal jugular vein and permitted to expand to a normal configuration, said wire frame contacts the wall of said one of the trachea or esophagus or internal jugular vein; and

means for placing said at least one wire of said wire frame in conductive communication with a source of electrical energy so as to electrically energize said one wire;

whereby when said forward end of said body member is inserted into said one of the trachea, esophagus, and internal jugular vein and said wire frame is permitted to expand to its normal configuration, said at least one wire is firmly imposed against said wall of said one of the trachea, esophagus, and internal jugular vein.

72. The device of claim 71, wherein said expandable frame comprises a plurality of wires.

73. The device of claim 72, wherein each of said plurality of wires of said wire frame is electrically insulated and isolated from the others of said plurality of wires, and wherein each of said plurality of wires can be individually electrically energized independently from the others of said plurality of wires.

74. The device of claim 72, wherein each wire of said wire frame is electrically insulated over its entire length and circumference except along the exterior aspect of a central portion of each wire where it contacts the interior of the wall of said one of said trachea, esophagus, and internal jugular vein when said stimulation device is appropriately positioned inside a patient and said wire frame is expanded.

75. The device of claim 71, further comprising a tube positionable around said wire frame to retain said wire frame in a compressed position and selectively displaceable with respect to said wire frame to expose said wire frame and thereby permit said wire frame to expand to its normal configuration.

76. The device of claim 71, wherein said at least one wire is substantially longitudinally oriented with respect to said elongated body member.

77. The device of claim 71, wherein said at least one wire is substantially circumferentially oriented with respect to said elongated body member.

78. The device of claim 71, wherein said wire frame is comprised of a shape memory metal.

79. The device of claim 71,

wherein said contractible wire frame comprises a proximal portion, a distal portion, and an intermediate portion;

wherein said device further comprises an elongated shaft linked to said distal portion of said wire frame;

wherein said proximal portion of said wire frame is fixed relative to said distal end of said elongated member; and

wherein said elongated shaft is longitudinally extensible with respect to said elongated body member so as to displace said proximal and distal portions of said wire frame away from one another so as to cause said intermediate portion of said wire frame to contract inward.

80. A device for electrically stimulating the vagus nerve of a patient, comprising:

an electrode positionable adjacent a vagus nerve of a patient;

an electrical pulse generator in conductive communication with said electrode, said pulse generator being capable of generating an electrical stimulus effective to cause controlled intermittent asystole when transmitted to said electrode and thereby communicated to said vagus nerve;

a cardiac monitoring device; and

a cardiac pacer for pacing the heart of said patient out of asystole;

whereby said patient'"'"'s heart can be put into asystole by actuating said electrical pulse generator and paced out of asystole by said cardiac pacer.

81. The device of claim 80, further comprising a foot switch operatively associated with said electrical pulse generator for actuating said generator to transmit an electrical stimulus to said electrode.

82. The device of claim 80, wherein said pulse generator remains active so long as said foot switch is closed, whereby the duration of said electrical stimulus generated by said pulse generator can be controlled by controlling the duration of closing said foot switch.

83. The device of claim 80, further comprising a foot switch operatively associated with said cardiac pacer for actuating said cardiac pacer to pace said patient'"'"'s heart out of asystole.

84. The device of claim 80, further comprising control circuitry operatively associated with said electrical pulse generator and said cardiac pacer, said control circuitry being operative to turn said cardiac pacer off when said electrical pulse generator is turned on.

85. The device of claim 80, further comprising control circuitry operatively associated with said electrical pulse generator, said cardiac monitoring device, and said cardiac pacer, said control circuitry being operative to automatically activate said cardiac pacer if said cardiac monitoring device does not sense a heartbeat within a predetermined time after cessation of vagal nerve stimulation.

86. The device of claim 80, further comprising a foot pedal operatively associated with said electrical pulse generator and said cardiac pacer, said switch being operative to activate said pulse generator and deactivate said cardiac pacer in response to a first press and release of said pedal, and to activate said cardiac pacer and deactivate said pulse generator in response to a second press and release of said pedal.

87. The device of claim 80, further comprising switch means responsive to voice activation operatively associated with said electrical pulse generator and said cardiac pacer, said switch being operative to activate said pulse generator and to deactivate said cardiac pacer in response to a first verbal command, and to activate said cardiac pacer and to deactivate said pulse generator in response to a second verbal command.

88. The device of claim 80, further comprising control circuitry operatively associated with said electrical pulse generator and said cardiac monitoring device, said control circuitry being operative to automatically control one or more of the frequency, amplitude, and amperage of said electrical pulse.