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

Patent metadata

Field	Value
Publication number	US-10588575-B2
Application number	US-201715422329-A
Country	US
Kind code	B2
Filing date	Feb 1, 2017
Priority date	Oct 28, 2010
Publication date	Mar 17, 2020
Grant date	Mar 17, 2020

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.

First claim

What is claimed is:

1. A method comprising:
determining an indicator of reliability of an analyte sensor comprising a first pair of sensor elements of a first probe and a second pair of sensor elements of a second probe, wherein the first and second pairs of sensor elements collectively comprise at least four distinct sensor elements, wherein the indicator of reliability is based, at least in part, on a sensor integrity determination,
wherein the sensor integrity determination is based, at least in part, on electrical current values for distinct electrical currents generated by corresponding ones of the at least four distinct sensor elements, wherein the distinct electrical currents generated by the corresponding ones of the at least four distinct sensor elements are representative of a concentration of glucose in a fluid,
wherein the sensor integrity determination is further based, at least in part, on a first voltage value corresponding to a voltage between sensor elements of the first pair of sensor elements and a second voltage value corresponding to a voltage between sensor elements of the second pair of sensor elements, wherein the first and second voltage values are indicative of a sensitivity and/or dynamic range in responding to the concentration of the glucose in the fluid; and
generating a sensor glucose signal and a sensor status signal based, at least in part, on the indicator of reliability.

2. The method of claim 1 , wherein the sensor status signal comprises status signals for corresponding sensor elements of the first and second pairs of sensor elements.

3. The method of claim 1 , further comprising determining a weighting of the electrical current values for the electrical current generated by the at least four distinct sensor elements, and wherein the sensor integrity determination is based, at least in part, on the weighting.

4. The method of claim 1 , wherein the sensor integrity determination is based, at least in part, on a trend metric or a noise metric, or a combination thereof.

5. The method of claim 4 , wherein the trend metric is based, at least in part, on one or more detected non-physiological anomalies.

6. The method of claim 4 , wherein the sensor integrity determination is also based, at least in part, on indications of past sensor behavior.

7. The method of claim 1 , and further comprising transitioning a system from providing closed-loop continuous insulin infusion to a patient from an infusion pump to an open loop or manual operation based, at least in part, on the indicator of reliability.

8. An apparatus comprising:
an analyte sensor to generate signals responsive to a concentration of glucose in a fluid, the analyte sensor comprising two or more pairs of sensor elements including at least a first pair of sensor elements of a first probe and a second pair of sensor elements of a second probe, wherein the first and second pairs of sensor elements collectively comprise at least four distinct sensor elements; and
one or more processors to:
determine an indicator of reliability of the analyte sensor based, at least in part, on a sensor integrity determination,
wherein the sensor integrity determination is based, at least in part, on electrical current values for distinct electrical currents generated by corresponding ones of the at least four distinct sensor elements, wherein the distinct electrical current generated by corresponding ones of the at least four distinct sensor elements are representative of the concentration of the glucose,
wherein the sensor integrity determination is further based, at least in part, on a first voltage value corresponding to a voltage between sensor elements of the first pair of sensor elements and a second voltage value corresponding to a voltage between sensor elements of the second pair of sensor elements, wherein the first and second voltage values are indicative of a sensitivity and/or dynamic range in responding to the concentration of the glucose in the fluid; and
generate a sensor glucose signal and a sensor status signal based, at least in part, on the indicator of reliability.

9. The apparatus of claim 8 , wherein the sensor status signal comprises status signals for corresponding sensor elements of the first and second pairs of sensor elements.

10. The apparatus of claim 8 , wherein the one or more processors are further to determine a weighting of the electrical current values for the electrical current generated by the at least four distinct sensor elements, and wherein the sensor integrity determination is based, at least in part, on the weighting.

11. The apparatus of claim 8 , wherein the one or more processors are further configured to determine the sensor integrity based, at least in part, on a trend metric or a noise metric, or a combination thereof.

12. The apparatus of claim 11 , wherein the trend metric is based, at least in part, on one or more detected non-physiological anomalies.

13. The apparatus of claim 11 , wherein the one or more processors are further configured to determine the sensor integrity based, at least in part, on indications of past sensor behavior.

14. The apparatus of claim 8 , wherein the apparatus is for use with a patient and for use with an infusion pump, and wherein the one or more processors are further to initiate transition of a system from providing closed-loop continuous insulin infusion to the patient from the infusion pump to an open loop or manual operation based, at least in part, on the indicator of reliability.

15. An apparatus comprising:
means for determining an indicator of reliability of an analyte sensor comprising a first pair of sensor elements of a first probe and a second pair of sensor elements of a second probe, wherein the first and second pairs of sensor elements collectively comprise at least four distinct sensor elements, wherein the indicator of reliability is based, at least in part, on a sensor integrity determination,
wherein the sensor integrity determination is based, at least in part, on electrical current values for distinct electrical currents generated by corresponding ones of the at least four distinct sensor elements, wherein the distinct electrical currents generated by the corresponding ones of the at least four distinct sensor elements are representative of a concentration of glucose in a fluid,
wherein the sensor integrity determination is further based, at least in part, on a first voltage value corresponding to a voltage between sensor elements of the first pair of sensor elements and a second voltage value corresponding to a voltage between sensor elements of the second pair of sensor elements, wherein the first and second voltage values are indicative of a sensitivity and/or dynamic range in responding to the concentration of the glucose in the fluid; and
means for generating a sensor glucose signal and a sensor status signal based, at least in part, on the indicator of reliability.

16. The apparatus of claim 15 , wherein the apparatus is for use with a patient and for use with an infusion pump, the apparatus further comprising means for transitioning a system from providing closed-loop continuous insulin infusion to the patient from the infusion pump to an open loop or manual operation based, at least in part, on the indicator of reliability.

Assignees

• Medtronic Minimed Inc

Inventors

• Gottlieb Rebecca K
• Luo Ying
• Gautham Raghavendhar
• Liang Bradley
• Roy Anirban
• Cooper Kenneth W
• Shah Rajiv
• Keenan Barry

Classifications

• A61M2230/201

  Glucose concentration · CPC title

• A61B5/4839

  combined with drug delivery · CPC title

• A61B5/6849

  in combination with a needle set · CPC title

• A61B5/14532

  for measuring glucose, e.g. by tissue impedance measurement · CPC title

• A61B5/7275

  Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor · CPC title