Calibration of analyte measurement system

• US 10,092,229 B2
• Filed: 06/29/2011
• Issued: 10/09/2018
• Est. Priority Date: 06/29/2010
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Taub, Marc Barry, Harper, Wesley Scott, Berman, Glenn Howard, Huang, Jean Mei
• Primary Examiner(s): Mallari, Patricia
• Assistant Examiner(s): TOTH, KAREN E
• Application Number:
  US13/172,823
• Publication Number:
  US 20120108931A1
• Time in Patent Office: 2,659 Days
• Field of Search: 600347, 600365
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: G16H 20/00 ICT specially adapted for therapies or health-improving plans, e.g. for handling prescriptions, for steering therapy or for monitoring patient compliance
• CPC Class Codes: G16H 20/10 relating to drugs or medications, e.g. for ensuring correct administration to patients
• CPC Class Codes: G16H 40/40 for the management of medical equipment or devices, e.g. scheduling maintenance or upgrades

Abstract

A method of calibrating an analyte measurement system is provided.

Claims

1. A method, the method comprising:

positioning a portion of an analyte sensor through a skin surface in fluid contact with biofluid under the skin surface of a subject;

generating a signal from the analyte sensor, the signal corresponding to an analyte concentration level in the biofluid;

storing, using one or more processors, a pre-set calibration schedule and at least one user-defined time period having a beginning time set by the subject and an ending time set by the subject;

prompting, using the one or more processors, the subject to assay a calibration sample of the subject'"'"'s blood to obtain a calibration value only when a first condition is met;

selecting, using the one or more processors, a first time frame and a maximum number of calibrations in the first time frame;

confirming, using the one or more processors, that a time for prompting the subject to assay the calibration sample is outside of the user-defined time period; and

correlating, using the one or more processors, the calibration value to at least one of the signals from the sensor when the first condition is met;

wherein the first condition is met when fewer than the maximum number of calibrations have occurred in the first time frame; and

prior to prompting the subject to assay the calibration sample, performing a data validation routine including a check for sensor electronics hardware error, a check on the data quality, and a check for current and/or voltage saturation.

2. The method of claim 1, further comprising selecting a second time frame.

3. The method of claim 2, further comprising selecting a maximum number of calibrations in the second time frame.

4. The method of claim 3, wherein the first condition is met when fewer than the maximum number of calibrations have occurred in the second time frame.

5. The method of claim 1, further comprising prompting the subject to assay a calibration sample of the subject'"'"'s blood to obtain a calibration value, when a second condition is met.

6. The method of claim 5, further comprising prompting the subject to assay a calibration sample of the subject'"'"'s blood to obtain a calibration value, when a third condition is met.

7. The method of claim 6, further comprising determining a presence of a condition relating to the subject.

8. The method of claim 7, wherein the condition relating to the subject comprises a determination of whether the subject is asleep.

9. The method of claim 7, wherein the third condition is met when the condition relating to the subject does not exist.

10. The method of claim 5, wherein the second condition is met when a waiting period between a previous calibration event associated with the pre-set calibration schedule and the time when the subject was prompted to assay the calibration sample has elapsed.

11. The method of claim 1, wherein the analyte concentration level is a glucose concentration level.

12. The method of claim 1, wherein obtaining the calibration value comprises determining a calibration measurement in less than or equal to about 1 μ

L of blood.

13. The method of claim 1, wherein the calibration value is compared to at least one of the signals from the sensor to calibrate the sensor.

14. The method of claim 1, further comprising:

confirming that a calibration sample was not obtained within a predetermined period of time after the prompting the subject to assay the calibration sample has elapsed;

confirming that a reference measurement is available during a period of time prior to the prompting the subject to assay the calibration sample; and

suppressing an alarm associated with confirming that the calibration sample was not obtained.

15. The method of claim 1, wherein the pre-set calibration schedule is not alterable by the subject.

16. An apparatus, comprising:

a processing unit; and

a memory coupled to the processing unit, the memory storing instructions which, when executed by the processing unit, causes the processing unit to receive a signal from a sensor in fluid contact with biofluid under a skin surface of a subject, the signal corresponding to an analyte concentration level in a biofluid, store a pre-set calibration schedule and at least one user-defined time period having a beginning time set by the subject and an ending time set by the subject, prompt the subject to assay a calibration sample of the subject'"'"'s blood to obtain a calibration value, only when a first condition is met, select a first time frame and a maximum number of calibrations in the first time frame, confirm that a time for prompting the subject to assay the calibration sample is outside of the user-defined time period, and correlate the calibration value to at least one of the signals from the sensor when the first condition is met, wherein the first condition is met when fewer than the maximum number of calibrations have occurred in the first time frame, and further, wherein prior to the processing unit prompting the subject to assay the calibration sample, the memory further includes instructions which, when executed by the processing unit, causes the processing unit to perform a data validation routine including a check for sensor electronics hardware error, a check on the data quality, and a check for current and/or voltage saturation.

17. The apparatus of claim 16, wherein the memory further includes instructions which, when executed by the processing unit, causes the processing unit to select a second time frame.

18. The apparatus of claim 17, wherein the memory further includes instructions which, when executed by the processing unit, causes the processing unit to select a maximum number of calibrations in the second time frame.

19. The apparatus of claim 18, wherein the first condition is met when fewer than the maximum number of calibrations have occurred in the second time frame.

20. The apparatus of claim 16, wherein the memory further includes instructions which, when executed by the processing unit, causes the processing unit to prompt the subject to assay a calibration sample of the subject'"'"'s blood to obtain a calibration value, when a second condition is met.

21. The apparatus of claim 20, wherein the memory further includes instructions which, when executed by the processing unit, causes the processing unit to prompt the subject to assay a calibration sample of the subject'"'"'s blood to obtain a calibration value, when a third condition is met.

22. The apparatus of claim 21, wherein the memory further includes instructions which, when executed by the processing unit, causes the processing unit to determine a presence of a condition relating to the subject.

23. The apparatus of claim 22, wherein the condition relating to the subject comprises a determination of whether the subject is asleep.

24. The apparatus of claim 22, wherein the third condition is met when the condition relating to the subject does not exist.

25. The apparatus of claim 20, wherein the second condition is met when a waiting period between a previous calibration event associated with the pre-set calibration schedule and the time when the subject was prompted to assay the calibration sample has elapsed.

26. The apparatus of claim 16, wherein the analyte concentration level is a glucose concentration level.

27. The apparatus of claim 16, wherein the instructions to obtain the calibration value include instructions to determine a calibration measurement in less than or equal to about 1 μ

L of blood.

28. The apparatus of claim 16, wherein the calibration value is compared to at least one of the signals from the sensor to calibrate the sensor.