Determination and application of glucose sensor reliability indicator and/or metric

• US 9,579,066 B2
• Filed: 11/12/2014
• Issued: 02/28/2017
• Est. Priority Date: 10/28/2010
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Gottlieb, Rebecca K., Luo, Ying, Gautham, Raghavendhar, Liang, Bradley, Roy, Anirban, Cooper, Kenneth W., Shah, Rajiv, Keenan, Barry
• Primary Examiner(s): Martin, Laura
• Assistant Examiner(s): Campbell, Irving A
• Application Number:
  US14/539,855
• Publication Number:
  US 20150073244A1
• Time in Patent Office: 839 Days
• Field of Search: 702/104, 702/106, 600/316, 600/319, 600/347, 600/365, 73/10.2
• US Class Current: 1/1
• CPC Class Codes: A61B 5/14503 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors A61B5/1459, A61B5/1464, A61B5/1473, A61B5/1482, A61B5/14865 take precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/6849 in combination with a needle set
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/743 Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots
• CPC Class Codes: A61M 2005/1726 the body parameters being measured at, or proximate to, the infusion site
• CPC Class Codes: A61M 2205/3303 Using a biosensor
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

Disclosed are a system and method for determining a metric and/or indicator of a reliability of a blood glucose sensor in providing glucose measurements. In one aspect, the metric and/or indicator may be computed based, at least in part, on an observed trend associated with signals generated by the blood glucose sensor.

Claims

1. A method comprising:

determining an indicator of reliability of a blood glucose sensor, the blood glucose sensor comprising at least a first probe and a second probe, the first and second probes comprising two or more pairs of sensor elements, the indicator of reliability of the blood glucose sensor being based, at least in part, on an observed correlation of output signals generated by at least a first pair of the pairs of sensor elements; and

generating a signal to suggest replacement of the blood glucose sensor based, at least in part, on the indicator of reliability of the blood glucose sensor.

2. The method of claim 1, wherein the indicator of reliability of the blood glucose sensor is further based, at least in part, on an additional observed correlation of output signals generated by at least a second pair of the pairs of sensor elements.

3. The method of claim 1, further comprising displaying an image on a display based, at least in part, on the indicator of reliability.

4. The method of claim 1, wherein the blood glucose sensor is coupled to an insulin pump as part of a system to provide closed-loop continuous insulin infusion to a patient, the method further comprising transitioning the system from closed loop operation to an open loop or manual operation based, at least in part, on the indicator of reliability.

5. The method of claim 1, further comprising displaying an indicator requesting additional or more frequent metered blood glucose reference samples for calibration of the blood glucose sensor in response to the indicator of reliability to thereby extend an operating life of the blood glucose sensor.

6. The method of claim 1, wherein the indicator of reliability is further based, at least in part, on an observed trend in output signals generated by the blood glucose sensor.

7. The method of claim 6, wherein the observed trend comprises detection of a reduced sensitivity of the blood glucose sensor in responding to a presence of glucose.

8. The method of claim 6, wherein the observed trend comprises further comprises one or more detected non-physiological anomalies.

9. The method of claim 6, wherein the observed trend comprises a sensor drift.

10. The method of claim 6, wherein the observed trend comprises a noise trend.

11. The method of claim 1, wherein the indicator of reliability further based, at least in part, on an indicator of a reliability of a calibration of the blood glucose sensor.

12. An apparatus comprising:

a blood glucose sensor to generate signals responsive to a concentration of glucose in a fluid, the blood glucose sensor comprising at least a first probe and a second probe, the first and second probes comprising two or more pairs of sensor elements;

one or more processors to;

determine an indicator of reliability of the blood glucose sensor, the indicator of reliability of the blood glucose sensor being based, at least in part, on an observed correlation of output signals generated by at least a first pair of the pairs of sensor elements; and

generate a signal to suggest replacement of the blood glucose sensor based, at least in part, on the indicator of reliability of the blood glucose sensor.

13. The apparatus of claim 12, wherein the indicator of reliability of the blood glucose sensor is further based, at least in part, on an additional observed correlation of output signals generated by at least a second pair of the pairs of sensor elements.

14. The apparatus of claim 12, further comprising a display device, wherein the one or more processors are further to initiate an image on the display device based, at least in part, on the indicator of reliability.

15. The apparatus of claim 12, further comprising an insulin pump coupled to the blood glucose sensor as part of a system to provide closed-loop continuous insulin infusion to a patient, wherein the one or more processors are further to initiate transition of the system from closed loop operation to an open loop or manual operation based, at least in part, on the indicator of reliability.

16. The apparatus of claim 12, further comprising a display device, wherein the one or more processors are further to initiate an image on the display device, the image requesting additional or more frequent metered blood glucose reference samples for calibration of the blood glucose sensor in response to the indicator of reliability to thereby extend an operating life of the blood glucose sensor.

17. The apparatus of claim 12, wherein the indicator of reliability is further based, at least in part, on an observed trend in the output signals generated by the blood glucose sensor.

18. An article comprising:

a non-transitory storage medium comprising machine-readable instructions stored thereon which are executable by a special purpose computing apparatus to;

determine an indicator of reliability of a blood glucose sensor, the blood glucose sensor comprising at least a first probe and a second probe, the first and second probes comprising two or more pairs of sensor elements, the indicator of reliability of the blood glucose sensor being based, at least in part, on an observed correlation of output signals generated by at least a first pair of the pairs of sensor elements; and

generate a signal to suggest replacement of the blood glucose sensor based, at least in part, on the indicator of reliability of the blood glucose sensor.

19. The article of claim 18, wherein the indicator of reliability of the blood glucose sensor is further based, at least in part, on an additional observed correlation of output signals generated by at least a second pair of the pairs of sensor elements.

20. The article of claim 18, wherein the instructions are further executable by the special purpose computing apparatus to initiate an image on a display device based, at least in part, on the indicator of reliability.

21. The article of claim 18, wherein the instructions are further executable by the special purpose computing apparatus to initiate transition of a system from closed loop operation to an open loop or manual operation based, at least in part, on the indicator of reliability, the system comprising an insulin pump coupled to the blood glucose sensor.

22. The article of claim 18, wherein the instructions are further executable by the special purpose computing apparatus to initiate an image on a display device, the image requesting additional or more frequent metered blood glucose reference samples for calibration of the blood glucose sensor in response to the indicator of reliability to thereby extend an operating life of the blood glucose sensor.

23. The article of claim 18, wherein the indicator of reliability is further based, at least in part, on an observed trend in output signals generated by the blood glucose sensor.