Transcutaneous analyte sensor

• US 7,774,145 B2
• Filed: 01/18/2006
• Issued: 08/10/2010
• Est. Priority Date: 08/01/2003
• Status: Active Grant

Abstract

The present invention relates generally to systems and methods for measuring an analyte in a host. More particularly, the present invention relates to systems and methods for transcutaneous measurement of glucose in a host. In some embodiments, a device is provided for monitoring glucose concentration in a host, including a continuous glucose sensor and an integrated receiver including a single point glucose monitor. In some embodiments, a computer system is provided that determines a rate of change of continuous analyte sensor data.

Claims

1. A device for monitoring glucose concentration in a host, the device comprising:

a substantially continuous glucose sensor configured to produce sensor data indicative of a glucose concentration in a host;

an integrated receiver configured to receive the sensor data from the substantially continuous glucose sensor, wherein the integrated receiver comprises;

an in vitro single point glucose monitor configured to receive a biological sample from the host and to measure a glucose concentration in the sample;

a processor module; and

a computer readable memory comprising;

instructions configured to cause the processor module to calibrate the sensor data received from the substantially continuous glucose sensor;

instructions configured to cause the processor module to determine a rate of change of the calibrated sensor data, to determine whether the rate of change is within a range of rates of change delimited by maximum normally sustainable rates of change of glucose in humans, and to not allow the processor module to calibrate the sensor data when the rate of change is outside the range;

instructions configured to cause the processor module to estimate at least one projected glucose concentration value based at least in part on a linear extrapolation of calibrated sensor data and on a variation analysis; and

instructions configured to cause the processor module to activate an alarm when the projected glucose concentration value is greater than a high threshold value or less than a low threshold value.

2. The device of claim 1, wherein the integrated receiver further comprises a user interface, wherein the user interface is configured to request a biological sample for measurement via the single point glucose monitor when the rate of change of the calibrated sensor data is within the range.

3. The device of claim 1, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive user information from an external source and process the user information received from the external source.

4. The device of claim 1, wherein the computer readable memory further comprises instructions configured to detect at least one of present hypoglycemia, predicted hypoglycemia, present hyperglycemia, or predicted hypoglycemia, wherein the instructions are configured to trigger an alarm or alert in response to the a detection.

5. The device of claim 1, wherein the integrated receiver comprises a user interface configured to simultaneously display calibrated sensor data and the glucose concentration measured by the single point glucose monitor.

6. The device of claim 1, wherein the computer readable memory further comprises instructions configured to cause the processor module to process and send data to an external device.

7. The device of claim 1, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process a therapy recommendation from an external source.

8. The device of claim 1, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process software updates from an external source.

9. The device of claim 1, wherein the dimensions of the integrated receiver comprise a length of less than about 15 cm, a width of less than about 10 cm, and a thickness of less than about 3.5 cm.

10. The device of claim 1, wherein a volume of the integrated receiver is less than about 180 cm³.

11. The device of claim 1, wherein a weight of the integrated receiver is less than about 130 g.

12. The device of claim 1, wherein the integrated receiver comprises a cell phone.

13. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than about +/−

20% over 5 minutes.

14. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than about +/−

25% over 5 minutes.

15. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than about +/−

30% over 5 minutes.

16. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than about +/−

4 mg/dL/min.

17. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than about +/−

5mg/dL/min.

18. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than about +/−

6 mg/dL/min.

19. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than at least one of about +/−

20% over 5 minutes or about +/−

4 mg/dL/min.

20. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than at least one of about +/−

25% over 5 minutes or about +/−

5 mg/dL/min.

21. The device of claim 1, wherein the maximum normally sustainable rates of change of glucose in humans are greater than at least one of about +/−

30% over 5 minutes or about +/−

6 mg/dL/min.

22. The device of claim 1, wherein the instructions are configured to allow the processor module to calibrate the sensor data when the rate of change is within the range.

23. The device of claim 3, wherein the user information comprises information selected from the group consisting of mealtime information, exercise information, insulin administration, therapy recommendations, and reference glucose values

24. The device of claim 6, wherein the instructions configured cause the processor module to process and send data to an external device are configured to cause the processor module to process and send at least one of an alert, a warning, or a message to a telecommunication device.

25. The device of claim 6, wherein the instructions configured cause the processor module to process and send data to an external device are configured to cause the processor module to process and send a therapy recommendation to an insulin delivery device.

26. The device of claim 6, wherein the external device comprises at least one of a pacemaker, an infusion device, or a telemetry device.

27. The device of claim 25, wherein the therapy recommendation comprises at least one of an amount of insulin or a time for insulin delivery.

28. A device for monitoring glucose concentration in a host, the device comprising:

a substantially continuous glucose sensor configured to produce sensor data indicative of a glucose concentration in a host;

an integrated receiver configured to receive the sensor data from the substantially continuous glucose sensor, wherein the integrated receiver comprises;

an in vitro single point glucose monitor configured to receive a biological sample from the host and to measure a glucose concentration in the sample;

a processor module; and

a computer readable memory comprising;

instructions configured to cause the processor module to calibrate the sensor data received from the substantially continuous glucose sensor during normal physiological rates of change;

instructions configured to cause the processor module to determine a rate of change of the calibrated sensor data;

instructions configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

4 mg/dL/min;

instructions configured to cause the processor module to estimate at least one projected glucose concentration value based at least in part on a linear extrapolation of calibrated sensor data and on a variation analysis; and

instruction configured to cause the processor module to activate an alarm when the projected glucose concentration value is greater than a high threshold value or less than a low threshold value.

29. The device of claim 28, wherein instructions configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

4 mg/dL/min is configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

5 mg/dL/min.

30. The device of claim 28, wherein instructions configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

4 m /dL/min is configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

6 mg/dL/min.

31. The device of claim 28, wherein the integrated receiver further comprises a user interface, wherein the user interface is configured to request a biological sample for measurement via the single point glucose monitor only when the rate of change of the calibrated data stream is not determined to be greater than about +/−

4 mg/dL/min.

32. The device of claim 28, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive user information from an external source and process the user information received from the external source.

33. The device of claim 28, wherein the computer readable memory further comprises instructions configured to cause the processor module to detect at least one condition selected from the group consisting of present hypoglycemia, predicted hypoglycemia, present hyperglycemia and predicted hypoglycemia, wherein the instructions are configured to trigger an alarm or alert in response to a detection.

34. The device of claim 28, wherein the integrated receiver further comprises a user interface configured to display continuous glucose sensor data and single point glucose monitor data.

35. The device of claim 28, wherein the computer readable memory further comprises instructions configured to cause the processor module to process and send data to an external device.

36. The device of claim 28, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process a therapy recommendation from an external source.

37. The device of claim 28, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process software updates from an external source.

38. The device of claim 28, wherein the dimensions of the integrated receiver comprise a length of less than about 15 cm, a width of less than about 10 cm, and a thickness of less than about 3.5 cm.

39. The device of claim 28, wherein a volume of the integrated receiver is less than about 180 cm³.

40. The device of claim 28, wherein the external device comprises at least one device selected from the group consisting of a pacemaker, an infusion device, and a telemetry device.

41. The device of claim 28, wherein the integrated receiver comprises a cell phone.

42. The device of claim 32, wherein the user information comprises information selected from the group consisting of mealtime information, exercise information, insulin administration, therapy recommendations, and reference glucose values.

43. The device of claim 35, wherein the instructions configured to cause the processor module to process and send data to an external device are configured to cause the processor module to process and send at least one of an alert, a warning, or a message to a telecommunication device.

44. The device of claim 35, wherein the instructions configured to cause the processor to process and send data to an external device are configured to cause the processor module to process and send a therapy recommendation to an insulin delivery device.

45. The device of claim 35, wherein the external device comprises at least one device selected from the group consisting of a pacemaker, an infusion device, and a telemetry device.

46. The device of claim 44, wherein the therapy recommendation comprises at least one of an amount of insulin or a time for insulin delivery.

47. The device of claim 44, wherein the instructions are configured to allow the processor module to calibrate the sensor data when the rate of change is within the range.

48. A device for monitoring glucose concentration in a host, the device comprising:

a substantially continuous glucose sensor configured to produce sensor data indicative of a glucose concentration in a host;

an integrated receiver configured to receive the sensor data from the substantially continuous glucose sensor, wherein the integrated receiver comprises;

an in vitro single point glucose monitor configured to receive a biological sample from the host and to measure a glucose concentration in the sample;

a processor module; and

a computer readable memory comprising;

instructions configured to cause the processor module to calibrate the sensor data received from the substantially continuous glucose sensor;

instructions configured to cause the processor module to determine a rate of change of the calibrated sensor data, to determine whether the rate of change is within a range of rates of change delimited by maximum normally sustainable rates of change of glucose in humans, and to not allow the processor module to calibrate the sensor data when the rate of change is outside the range; and

instructions configured to cause a simultaneous display of a first output for the calibrated sensor data and a second output for the glucose concentration measured by the single point glucose monitor.

49. The device of claim 48, wherein the integrated receiver further comprises a user interface, wherein the user interface is configured to request a biological sample for measurement via the single point glucose monitor when the rate of change of the calibrated sensor data is within the range.

50. The device of claim 48, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive user information from an external source and process the user information received from the external source.

51. The device of claim 48, wherein the computer readable memory further comprises instructions configured to detect at least one of present hypoglycemia, predicted hypoglycemia, present hyperglycemia, or predicted hypoglycemia, wherein the instructions are configured to trigger an alarm or alert in response to a detection.

52. The device of claim 48, wherein the integrated receiver comprises a user interface configured to simultaneously display calibrated sensor data and the glucose concentration measured by the single point glucose monitor.

53. The device of claim 48, wherein the computer readable memory further comprises instructions configured to cause the processor module to process and send data to an external device.

54. The device of claim 48, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process a therapy recommendation from an external source.

55. The device of claim 48, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process software updates from an external source.

56. The device of claim 48, wherein the dimensions of the integrated receiver comprise a length of less than about 15 cm, a width of less than about 10 cm, and a thickness of less than about 3.5 cm.

57. The device of claim 48, wherein a volume of the integrated receiver is less than about 180 cm³.

58. The device of claim 48, wherein a weight of the integrated receiver is less than about 130 g.

59. The device of claim 48, wherein the integrated receiver comprises a cell phone.

60. The device of claim 48, wherein the maximum normally sustainable rates of change of glucose in humans are greater than about +/−

20% over 5 minutes.

61. The device of claim 48, wherein the maximum normally sustainable rate of change of glucose in humans are greater than about +/−

25% over 5 minutes.

62. The device of claim 48, wherein the maximum normally sustainable rate of change of glucose in humans are greater than about +/−

30% over 5 minutes.

63. The device of claim 48, wherein the maximum normally sustainable rate of change of glucose in humans are greater than about +/−

4 mg/dL/min.

64. The device of claim 48, wherein the maximum normally sustainable rate of change of glucose in humans are greater than about +/−

5 mg/dL/min.

65. The device of claim 48, wherein the maximum normally sustainable rate of change of glucose in humans are greater than about +/−

6 mg/dL/min.

66. The device of claim 50, wherein the user information comprises information selected from the group consisting of mealtime information, exercise information, insulin administration, therapy recommendations, and reference glucose values.

67. The device of claim 53, wherein the instructions configured cause the processor module to process and send data to an external device are configured to cause the processor module to process and send at least one of an alert, a warning, or a message to a telecommunication device.

68. The device of claim 53, wherein the instructions configured cause the processor module to process and send data to an external device are configured to cause the processor module to process and send a therapy recommendation to an insulin delivery device.

69. The device of claim 53, wherein the external device comprises at least one of a pacemaker, an infusion device, or a telemetry device.

70. The device of claim 68, wherein the therapy recommendation comprises at least one of an amount of insulin or a time for insulin delivery.

71. A device for monitoring glucose concentration in a host, the device comprising:

a substantially continuous glucose sensor configured to produce sensor data indicative of a glucose concentration in a host;

an integrated receiver configured to receive the sensor data from the substantially continuous glucose sensor, wherein the integrated receiver comprises;

an in vitro single point glucose monitor configured to receive a biological sample from the host and to measure a glucose concentration in the sample;

a processor module; and

a computer readable memory comprising;

instructions configured to cause the processor module to calibrate the sensor data received from the substantially continuous glucose sensor during normal physiological rates of change;

instructions configured to cause the processor module to determine a rate of change of the calibrated sensor data;

instructions configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

4 mg/dL/min; and

instructions configured to cause a simultaneous display of a first output for the calibrated sensor data and a second output for the glucose concentration measured by the single point glucose monitor.

72. The device of claim 71, wherein instructions configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

4 mg/dL/min is configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

5 mg/dL/min.

73. The device of claim 71, wherein instructions configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

4 mg/dL/min is configured to cause the processor module to not calibrate the sensor data using the glucose concentration measured by the single point glucose monitor when the rate of change of the calibrated sensor data is greater than about +/−

6 mg/dL/min.

74. The device of claim 71, wherein the integrated receiver further comprises a user interface, wherein the user interface is configured to request a biological sample for measurement via the single point glucose monitor only when the rate of change of the calibrated sensor data is not determined to be greater than about +/−

4 mg/dL/min.

75. The device of claim 71, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive user information from an external source and process the user information received from the external source.

76. The device of claim 71, wherein the computer readable memory further comprises instructions configured to cause the processor module to detect at least one condition selected from the group consisting of present hypoglycemia, predicted hypoglycemia, present hyperglycemia and predicted hypoglycemia, wherein the instructions are configured to trigger an alarm or alert in response to a detection.

77. The device of claim 71, wherein the integrated receiver further comprises a user interface configured to display continuous glucose sensor data and single point glucose monitor data.

78. The device of claim 71, wherein the computer readable memory further comprises instructions configured to cause the processor module to process and send data to an external device.

79. The device of claim 71, wherein the instructions configured to cause the processor to process and send data to an external device are configured to cause the processor module to process and send a therapy recommendation to an insulin delivery device.

80. The device of claim 71, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process a therapy recommendation from an external source.

81. The device of claim 71, wherein the computer readable memory further comprises instructions configured to cause the processor module to receive and process software updates from an external source.

82. The device of claim 71, wherein the dimensions of the integrated receiver comprise a length of less than about 15 cm, a width of less than about 10 cm, and a thickness of less than about 3.5 cm.

83. The device of claim 71, wherein a volume of the integrated receiver is less than about 180 cm³.

84. The device of claim 71, wherein a weight of the integrated receiver is less than about 130 g.

85. The device of claim 71, wherein the integrated receiver comprises a cell phone.

86. The device of claim 75, wherein the user information comprises information selected from the group consisting of mealtime information, exercise information, insulin administration, therapy recommendations, and reference glucose values.

87. The device of claim 71, wherein the instructions configured to cause the processor module to process and send data to an external device are configured to cause the processor module to process and send at least one of an alert, a warning, or a message to a telecommunication device.

88. The device of claim 71, wherein the external device comprises at least one device selected from the group consisting of a pacemaker, an infusion device, and a telemetry device.

89. The device of claim 79, wherein the therapy recommendation comprises at least one of an amount of insulin or a time for insulin delivery.