Apparatus for minimally invasive calibration of implanted pressure transducers

• US 7,862,513 B2
• Filed: 05/13/2003
• Issued: 01/04/2011
• Est. Priority Date: 05/14/2002
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Whiting, James, Eigler, Neal, Mann, Brian
• Primary Examiner(s): Mallari; Patricia C
• Application Number:
  US10/438,300
• Publication Number:
  US 20040019285A1
• Time in Patent Office: 2,793 Days
• Field of Search: 600/485, 600/529
• US Class Current: 600/486
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 2560/0257 using atmospheric pressure
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/03 Detecting, measuring or recording fluid pressure within the body other than blood pressure, e.g. cerebral pressure; Measuring pressure in body tissues or organs A61B5/205 takes precedence
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• CPC Class Codes: A61B 5/087 Measuring breath flow
• CPC Class Codes: A61B 5/418 lymph vessels, ducts or nodes
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: A61B 5/4884 inducing physiological or psychological stress, e.g. applications for stress testing

Abstract

This invention relates generally to apparatus and methods for the calibration of implanted pressure transducers. It is an object of several embodiments of the present invention to provide apparatus and methods for the calibration of one or more implanted pressure transducers implanted in the body of medical patients. Various embodiments of the present invention are particularly advantageous because they offer a calibration system that is less invasive than the systems currently available.

Claims

1. A pressure measurement calibration system comprising:

a first implantable sensor adapted to be implanted at a first location at least partially within a medical patient, wherein the first implantable sensor is configured to provide a first signal indicative of a first pressure at the first location at least partially within the medical patient;

a pressure signal receiver for receiving the first signal from the first sensor;

a second sensor for measuring a second pressure at a second location with respect to the medical patient and for generating a second signal indicative of said second pressure;

a processor configured to determine an adjustment factor based on said first signal, said second signal, and a perturbation, wherein said first sensor is configured to be calibrated based upon said adjustment factor;

a mouthpiece coupled to said second sensor; and

a communications device configured to deliver a patient instruction to said medical patient when said first pressure falls outside of a previously determined range.

2. The system of claim 1, wherein said first sensor is further operable to be calibrated based upon an absolute pressure.

3. The system of claim 1, wherein said first sensor is further operable to be calibrated based upon a reference pressure.

4. The system of claim 3, wherein said reference pressure is the second pressure.

5. The system of claim 1, wherein said first sensor is further operable to be calibrated based upon a gauge pressure.

6. The system of claim 5, wherein said gauge pressure is the second pressure.

7. The system of claim 1, wherein said second sensor comprises a manometer.

8. The system of claim 1, further comprising a display for displaying the second pressure.

9. The system of claim 1, further comprising a signal conditioning apparatus.

10. The system of claim 1, further comprising a calibrator operable to adjust at least one calibration parameter.

11. The system of claim 1, further comprising a calibrator operable to calibrate said one or more first sensors.

12. The system of claim 1, further comprising a memory coupled to at least one of said first and second sensors, wherein said memory is configured to store at least one calibration parameter.

13. The system of claim 1, wherein said patient instruction is to perform a calibration procedure.

14. The system of claim 1, wherein said patient instruction is to recalibrate said one or more second sensors.

15. The system of claim 1, wherein said patient instruction is to contact a physician.

16. The system of claim 1, wherein said patient instruction is provided when a difference between said first pressure and said second pressure falls outside a previously determined range.

17. The system of claim 1, wherein said patient instruction is provided when a temperature falls outside of a previously determined range.

18. The system of claim 1, wherein said patient instruction is provided when a date falls outside of a previously determined range.

19. The system of claim 1, wherein said patient instruction is to initiate said perturbation.

20. The system of claim 1, wherein said patient instruction is to control said perturbation.

21. The system of claim 1, further comprising an automatic therapy delivery device.

22. The system of claim 21, wherein said automatic therapy delivery device comprises an automatic drug delivery device.

23. The system of claim 21, wherein said automatic therapy delivery device comprises a cardiac defibrillator.

24. The system of claim 21, wherein said automatic therapy delivery device comprises a pacemaker.

25. The system of claim 21, wherein said automatic therapy delivery device comprises an oral drug management system.

26. The system of claim 21, wherein said automatic therapy delivery device provides a therapy level based at least in part on said first and second pressures.

27. The system of claim 21, wherein said automatic therapy delivery device is configured to provide a therapy type based at least in part upon said first and second pressures.

28. The system of claim 1, further comprising a transmitter for transmitting the first signal indicative of the first pressure to the pressure signal receiver.

29. The system of claim 28, wherein said transmitter comprises a radio frequency inductive coupling.

30. The system of claim 28, wherein said transmitter generates a radio frequency signal.

31. The system of claim 28, wherein said transmitter generates a digital signal.

32. The system of claim 28, wherein said transmitter generates an analog signal.

33. The system of claim 28, wherein said receiver comprises a hand-held digital communication device.

34. The system of claim 28, wherein said receiver comprises a computer.

35. The system of claim 28, wherein said receiver comprises a telephone.

36. The system of claim 28, wherein said receiver comprises a personal digital assistant.

37. The system of claim 28, wherein said receiver comprises a monitor.

71. The pressure measurement calibration system of claim 1, further comprising a display, wherein the display is configured to provide real-time feedback corresponding to said perturbation.

72. The pressure measurement calibration system of claim 71, wherein said feedback comprises an instruction to maintain a pressure during a time interval.

73. The pressure measurement calibration system of claim 1, wherein the perturbation comprises a valsalva maneuver.

38. A pressure measurement calibration system comprising:

one or more first sensors configured to generate a first signal indicative of a first pressure at a first location at least partially within a medical patient;

one or more second sensors configured to generate a second signal indicative of an upper airway pressure at a second location with respect to the medical patient, wherein said one or more second sensors comprises a mouthpiece;

a processor configured to calibrate said one or more first sensors in response to the first and second signals and at least one perturbation; and

an instruction module configured to provide a patient instruction based upon said first and second signals when at least one of said first and second signals falls outside of a previously determined range.

74. The pressure measurement calibration system of claim 38, wherein the perturbation comprises a valsalva maneuver.

39. A pressure measurement calibration system comprising:

a first implantable sensor adapted to be implanted at a first location at least partially within a medical patient and configured to provide a first signal indicative of a first pressure at the first location at least partially within the medical patient;

a communication device configured to receive the first signal from the first sensor;

one or more second sensors configured to provide a second signal indicative of a second pressure at a second location with respect to the medical patient; and

a processor configured to compute at least one calibration parameter based upon said first and second signals while said medical patient performs a valsalva maneuver,

wherein the communication device comprises programmed instructions for altering therapy based on said first signal and said at least one calibration parameter.

40. A pressure measurement calibration system comprising:

a first means for measuring a first pressure at a first location inside of a medical patient;

a second means for measuring an upper airway pressure of the medical patient at a second location with respect to the medical patient;

a processor, configured to calibrate said first means in response to a pressure perturbation and said first and upper airway pressures; and

an instruction module, wherein said instruction module provides a patient instruction based upon said first and the upper airway pressures when the first pressure falls outside of a previously determined range.

41. The system of claim 40, wherein said first means comprises one or more sensors.

42. The system of claim 40, wherein said second means comprises one or more sensors.

43. The system of claim 40, further comprising a perturber configured to induce said pressure perturbation.

44. The system of claim 40, further comprising means for displaying the second pressure to a patient.

45. The system of claim 40, further comprising a signal conditioning apparatus.

46. The system of claim 40, further comprising a memory coupled to said processor, wherein said processor is configured to store at least one calibration parameter with said memory.

47. The system of claim 40, further comprising a memory coupled to said processor, wherein said processor is configured to store at least one calibration coefficient with said memory.

48. The system of claim 40, wherein said patient instruction is to recalibrate said first sensor.

49. The system of claim 40, wherein said patient instruction is to recalibrate said second sensor.

50. The system of claim 40, wherein said patient instruction is to contact a physician.

51. The system of claim 40, wherein said patient instruction is provided when said first pressure falls outside of a previously determined range.

52. The system of claim 40, wherein said patient instruction is provided when said second pressure falls outside of a previously determined range.

53. The system of claim 40, wherein said patient instruction is provided when a temperature falls outside of a previously determined range.

54. The system of claim 40, wherein said patient instruction is provided when a date falls outside of a previously determined range.

55. The system of claim 40, further comprising an automatic drug delivery device.

56. The system of claim 40, further comprising a cardiac defibrillator.

57. The system of claim 40, further comprising a pacemaker.

58. The system of claim 40, further comprising an oral drug management system.

59. The system of claim 40, further comprising a means for transmitting a signal indicative of the first pressure to a means for receiving.

60. The system of claim 59, wherein said means for transmitting comprises a radio frequency inductive coupling.

61. The system of claim 59, wherein said means for transmitting generates a radio frequency signal.

62. The system of claim 59, wherein said means for transmitting generates a digital signal.

63. The system of claim 59, wherein said means for transmitting generates an analog signal.

64. The system of claim 59, wherein said means for receiving comprises a hand-held digital communication device.

65. The system of claim 59, wherein said means for receiving comprises a computer.

66. The system of claim 59, wherein said means for receiving comprises a telephone.

67. The system of claim 59, wherein said means for receiving comprises a personal digital assistant.

68. The system of claim 59, wherein said means for receiving comprises a monitor.

75. The pressure measurement calibration system of claim 40, wherein the pressure perturbation is a valsalva maneuver.

69. A calibration monitor for a pressure measurement system located at least partially inside of a medical patient, comprising:

a recorder to record a first atmospheric pressure corresponding to atmospheric pressure around a blood pressure measurement system at a first time and a second atmospheric pressure corresponding to atmospheric pressure around the blood pressure measurement system after a sampling period; and

a processor to calculate the difference between the first atmospheric pressure and the second atmospheric pressure,

wherein the processor is configured to provide an instruction to said medical patient to take an action based upon said difference, wherein said action is to recalibrate said pressure measurement system.

70. A calibration monitor for a pressure measurement system located at least partially inside of a medical patient, comprising:

a recorder to record a first atmospheric pressure corresponding to atmospheric pressure around a blood pressure measurement system at a first time and a second atmospheric pressure corresponding to atmospheric pressure around the blood pressure measurement system after a sampling period; and

a processor to calculate the difference between the first atmospheric pressure and the second atmospheric pressure,

wherein the processor is configured to provide an instruction to said medical patient to take an action based upon said difference, wherein said action is to contact a medical care provider.