Method and apparatus for monitoring blood condition and cardiopulmonary function

• US 20040082841A1
• Filed: 10/24/2002
• Published: 04/29/2004
• Est. Priority Date: 10/24/2002
• Status: Active Grant

• Current Assignee: Sensicor LLC
• Original Assignee: Sensicor LLC
• Inventors: Furnary, Anthony P., Lowe, Robert I.
• Granted Patent: US 7,010,337 B2
• Time in Patent Office: Days
• US Class Current: 600/325
• CPC Class Codes: A61B 2562/0233 Special features of optical sensors or probes classified in A61B5/00
• CPC Class Codes: A61B 2562/043 in a linear array
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence

Abstract

Sensors located on a sensor carrier are placed adjacent one or more of a surgical patient'"'"'s major thoracic blood-containing structures such as the aorta or pulmonary artery, and characteristics of blood in the blood-containing structures are determined noninvasively by measuring transmission or reflection of light or other types of energy by the blood. Emitters and receptors included in the sensors are connected electrically with suitable electronic signal generating and processing components in a package remote from the sensor carrier.

Claims

1. A method of at least partially evaluating a selected aspect of a patient'"'"'s metabolic function, comprising:

measuring separately at least one selected characteristic of blood present in each of at least two selected major thoracic blood-containing structures by using at least one electronic sensor located within said patient'"'"'s thoracic cavity, but outside said selected major thoracic blood-containing structures, to observe said blood through a respective wall of each of said selected major thoracic blood-containing structures without removing any of said blood from said selected major thoracic blood-containing structures, and comparing respective resulting values of said at least one selected characteristic as measured in each of said at least two selected major thoracic blood vessels.

2. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s aorta.

3. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s main pulmonary artery.

4. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s right pulmonary artery.

5. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s left pulmonary artery.

6. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s left atrium.

7. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s inferior vena cava.

8. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s superior vena cava.

9. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is of patient'"'"'s right atrium.

10. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is one of said patient'"'"'s pulmonary veins.

11. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s innominate artery.

12. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is one of said patient'"'"'s carotid arteries.

13. The method of claim 1, wherein one of said at least two selected major thoracic blood-containing structures is one of said patient'"'"'s subclavian arteries.

14. The method of any one of claims 3-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s aorta.

15. The method of any one of claims 2 and 4-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s main pulmonary artery.

16. The method of any one of claims 2-3 and 5-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s right pulmonary artery.

17. The method of any one of claims 2-4 and 6-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s left pulmonary artery.

18. The method of any one of claims 2-5 and 6-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s left atrium.

19. The method of any one of claims 2-6 and 7-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s inferior vena cava.

20. The method of any one of claims 2-7 and 8-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s superior vena cava.

21. The method of any one of claims 2-8 and 9-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s right atrium.

22. The method of any one of claims 2-9 and 10-13 wherein another one of said at least two selected major thoracic blood-containing structures is one of said patient'"'"'s pulmonary veins.

23. The method of any one of claims 2-10 and 11-13 wherein another one of said at least two selected major thoracic blood-containing structures is said patient'"'"'s innominate artery.

24. The method of any one of claims 2-11 and 13 wherein another one of said at least two selected major thoracic blood-containing structures is one of said patient'"'"'s carotid arteries.

25. The method of any of claims 2-12 wherein another one of said at least two selected major thoracic blood-containing structures is one of said patient'"'"'s subclavian arteries.

26. The method of claim 1, wherein said selected characteristic of blood is the degree of saturation by oxygen of hemoglobin in said blood.

27. The method of claim 1, wherein said selected characteristic of blood is hemoglobin content of said blood.

28. The method of claim 1, wherein said selected characteristic of blood is hematocrit of said blood.

29. The method of claim 1, wherein said selected characteristic of blood is pH of said blood.

30. The method of claim 1, wherein said selected characteristic of blood is glucose content of said blood.

31. The method of claim 1, wherein said selected characteristic of blood is potassium content of said blood.

32. The method of claim 1, wherein said selected characteristic of blood is lactate content of said blood.

33. The method of any of claims 27-32, including measuring the degree of saturation by oxygen of hemoglobin as a second one of said at least one selected characteristic of blood.

34. The method of any of claims 26 and 28-32, including measuring hemoglobin content as a second one of said at least one selected characteristic of blood.

35. The method of any of claims 26-27 and 29-32, including measuring hematocrit as a second one of said at least one selected characteristic of blood.

36. The method of any of claims 26-28 and 30-32, including measuring pH as a second one of said at least one selected characteristic of blood.

37. The method of any of claims 26-29 and 31-32, including measuring glucose content as a second one of said at least one selected characteristic of blood.

38. The method of any of claims 26-30 and 32, including measuring potassium content as a second one of said at least one selected characteristic of blood.

39. The method of any of claims 26-31, including measuring lactate content as a second one of said at least one selected characteristic of blood.

40. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is cardiac function.

41. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is cardiovascular function.

42. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is cardiopulmonary function.

43. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is pulmonary function.

44. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is glucose metabolism.

45. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is pH maintenance.

46. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is biochemical metabolic function.

47. The method of claim 1, wherein said selected aspect of a patient'"'"'s metabolic function is an abnormal shunt of blood, indicating either or both of an anatomic or a physiological deficiency of at least one of said patient'"'"'s heart and lungs.

48. The method of claim 1, including the additional step of introducing an identifying agent into said patient'"'"'s bloodstream to enable said electronic sensor to measure said at least one selected characteristic of said blood.

49. The method of claim 45 wherein said identifying agent causes fluorescence of said blood in response to receiving a pulse of energy from said electronic sensor and in relation to a level of one of said at least one selected characteristic of said blood.

50. The method of claim 1, including the further steps of:

(a) providing a sensor carrier with at least a first one of said at least one electronic sensor mounted thereon;

(b) surgically creating a space for said sensor carrier between two of said at least two selected major thoracic blood-containing structures;

(c) placing said sensor carrier in said space;

(d) directing a first quantity of energy toward a first of said selected major thoracic blood-containing structures from an emitter portion of said first one of said at least one electronic sensor and receiving a portion of said first quantity of energy in a receptor portion of said first sensor located closely adjacent said first of said selected major thoracic blood-containing structures, and forming an electrical signal from said receptor portion of said first one of said at least one electronic sensor representative of said portion of said energy received thereby;

(e) directing a second quantity of energy toward a second of said selected major thoracic blood-containing structures from an emitter portion of a second one of said at least one electronic sensor and receiving a portion of said second quantity of energy in a receptor portion of said second one of said at least one electronic sensor located closely adjacent said second of said selected major thoracic blood-containing structures, and forming an electrical signal from said receptor portion of said second one of said at least one electronic sensor representative of said portion of said energy received thereby;

(f) from said electrical signal from said receptor portion of said first one of said at least one electronic sensor determining a measurement of said at least one selected characteristic of said blood in said first of said selected major thoracic blood-containing structures; and

(g) from said electrical signal from said receptor portion of said second one of said at least one electronic sensor determining a level of said at least one selected characteristic of said blood in said second of said selected major thoracic blood-containing structures.

51. The method of claim 50, including the step of providing both said first and second ones of said electronic sensors on a first side of said sensor carrier.

52. The method of claim 51, including the step of temporarily fastening said sensor carrier to tissue associated with a major thoracic blood-containing structure adjacent said patient'"'"'s heart.

53. The method of claim 50, including the step of providing said sensor carrier with said first one of said electronic sensors mounted on a first side thereof and said second one of said sensors mounted on an opposite second side thereof.

54. The method of claim 53, including providing a third one of said at least one electronic sensor on said sensor carrier and placing said third one of said sensors adjacent a selected third major thoracic blood-containing structure of said patient and measuring an amount of a selected blood constituent present in blood in said third major thoracic blood-containing structure by evaluating transmission and reception of a selected form of energy by said third one of said sensors through a wall of said third major thoracic blood-containing structure.

55. The method of claim 50, including the steps of leaving said sensor carrier in place for an extended time after first measuring said at least one selected characteristic of said blood, and periodically again measuring said at least one selected characteristic of said blood during said extended time.

56. The method of claim 50, wherein said first and second one of said at least one electronic sensor measure said at least one selected characteristic of said blood by measuring transmission of light through said blood.

57. The method of claim 56, including the steps of separately measuring transmission of light having each of a plurality of different wavelengths through said blood.

58. The method of claim 50, including directing said quantities of energy from said first and second one of said at least one electric sensor substantially contemporaneously toward said first and second of said selected major thoracic blood-containing structures.

59. The method of claim 50, wherein said first and second quantities of energy are light energy.

60. The method of claim 50, wherein said space is between said patient'"'"'s aorta and right pulmonary artery, including the additional step of surgically forming a further space adjacent said patient'"'"'s inferior vena cava and placing a part of said sensor carrier carrying a third sensor into said further space.

61. The method of claim 50 including the step of providing at least one said electronic sensor on a second sensor carrier and placing said second sensor carrier adjacent a respective one of said at least two selected major thoracic blood-containing structures.

62. The method of claim 1 including measuring separately at least two selected characteristics of blood present in at least one of said at least two selected major thoracic blood-containing structures by using said at least one electronic sensor.

63. The method of claim 1 including measuring said selected characteristic of blood substantially simultaneously in each of said at least two selected major blood-containing structures.

64. Apparatus for measuring a selected characteristic of a patient'"'"'s blood, comprising:

(a) a sensor carrier;

(b) first and second sensors mounted on said sensor carrier and spaced apart from each other by a predetermined distance, each of said first and second sensors having a respective receptor capable of providing a receptor output signal representative of a level of a selected characteristic of blood within an adjacent blood-containing structure, said sensor carrier and said first and second sensors all being small enough to be placed within said patient'"'"'s body cavity and proximate said patient'"'"'s heart, permitting substantially simultaneous observation of blood in a first blood vessel by said first sensor and of blood in a second blood vessel by said second sensor.

65. The apparatus of claim 64, wherein said sensor carrier has a coating of a hydrophilic material.

66. The apparatus of claim 64 wherein each of said first and second sensors includes an emitter adapted to transmit energy into blood within a respective one of said first and second blood vessels, and a receptor sensitive to energy from said emitter that has passed through said blood inside respective one of said first and second blood vessels.

67. The apparatus of claim 66 wherein said emitter of one of said sensors is a radio frequency transmitter and said receptor of said one of said sensors is a radio frequency receiver.

68. The apparatus of claim 66 wherein each of said emitters is an electrically driven light emitter.

69. The apparatus of claim 66 wherein one of said sensors includes a plurality of said receptors, each of said receptors measuring reception of light in a different respective wavelength and providing a respective signal representative thereof.

70. The apparatus of claim 64 wherein at least one of said sensors separately measures reception of light in each of a plurality of different wavelengths and provides a respective signal representative of reception of light in each of said different wavelengths.

71. The apparatus of claim 64 wherein one of said sensors includes an ultrasound transducer.

72. The apparatus of claim 64 wherein said sensor carrier includes a suture tab.

73. The apparatus of claim 64, including a sterile protective sleeve surrounding said sensor carrier.

74. The apparatus of claim 64, wherein said sensor carrier is of a flexible material.

75. The apparatus of claim 64 wherein said sensor carrier includes an elongate ribbon-like member having a pair of opposite faces and wherein said emitter and receptor are both on the same one of said opposite faces.

76. The apparatus of claim 64, wherein said sensor carrier includes an elongate ribbon-like member having a pair of opposite faces, and wherein said first sensor is directed outwardly from a first one of said pair of opposite faces and said second sensor is directed outwardly from the other one of said pair of opposite faces.

77. The apparatus of claim 76 wherein said sensor carrier includes an emission-opaque central layer located between said opposite faces and separating said first and second sensors from each other.

78. The apparatus of claim 64 including a cable including a plurality of cardiac pacing leads, and wherein said sensors are connected to a control unit through said cable.

79. The apparatus of claim 64 including a cable associated with a ventricular assist device, and wherein said sensors are connected electrically with a control unit through conductors included in said cable.

80. The apparatus of claim 64 wherein said control unit is connected electrically with a control unit of a ventricular assist device thereby providing to said ventricular assist device a signal representative of a patient'"'"'s cardiac function.

81. The apparatus of claim 64 wherein said control unit is connected electrically with a control unit of a ventricular assist device thereby providing to said ventricular assist device a signal representative of a patient'"'"'s cardiopulmonary function.

82. The apparatus of claim 64, including a cable associated with an artificial heart, and wherein said sensors are connected electrically with a control unit through conductors included in said cable.

83. The apparatus of claim 82 wherein said control unit is connected electrically with a controller of an artificial heart, thereby providing to said control unit of said artificial heart a signal representative of how effectively said artificial heart is functioning.

84. The apparatus of claim 64, including a cable associated with a pacemaker, and wherein said sensors are connected electrically with a control unit through said cable.

85. The apparatus of claim 64 wherein said control unit is connected electrically with a control unit of a pacemaker thereby providing to said pacemaker a signal representative of a patient'"'"'s cardiac function.

86. The apparatus of claim 64 wherein said sensors are connected electrically with a control unit through a cable attached to a mediastinal chest drain tube.

87. The apparatus of claim 64 further including a second sensor carrier and a respective sensor mounted thereon capable of providing a receptor output signal representative of a level of a respective selected characteristic of blood in an adjacent blood-containing structure.

88. The apparatus of claim 64 wherein each of said sensors is connected functionally with an implantable control unit equipped to communicate percutaneously with an external unit.