Method of Calibrating an Analyte-Measurement Device, and Associated Methods, Devices and Systems

• US 20090265129A1
• Filed: 06/29/2009
• Published: 10/22/2009
• Est. Priority Date: 10/31/2003
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Inventors: Feldman, Benjamin J., McGarraugh, Geoffrey V.
• Granted Patent: US 8,219,174 B2
• Time in Patent Office: Days
• US Class Current: 702/104
• CPC Class Codes: A61B 5/0004 characterised by the type of physiological signal transmitted
• CPC Class Codes: A61B 5/0024 for multiple sensor units attached to the patient, e.g. using a body or personal area network
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/6898 Portable consumer electronic devices, e.g. music players, telephones, tablet computers
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick

Abstract

The invention relates to a method for calibrating an analyte-measurement device that is used to evaluate a concentration of analyte in bodily fluid at or from a measurement site in a body. The method involves measuring a concentration, or calibration concentration, of an analyte in blood from an “off-finger” calibration site, and calibrating the analyte-measurement device based on that calibration concentration. The invention also relates to a device, system, or kit for measuring a concentration of an analyte in a body, which employs a calibration device for adjusting analyte concentration measured in bodily fluid based on an analyte concentration measured in blood from an “off-finger” calibration site.

Claims

1. An in vivo analyte sensor calibration system, comprising:

an in vivo analyte sensor, at least a portion of the sensor subcutaneously positioned to generate one or more signals;

a transmission element operatively coupled to the in vivo analyte sensor and configured to transmit one or more analyte-related signals of the in vivo analyte sensor;

a calibration sensor configured to be placed in contact with a blood sample from an off-finger calibration site to provide a calibration measurement; and

a data processing element configured to physically couple with the calibration sensor to communicate with the transmission element, the data processing element further configured to determine a quality of the calibration measurement and a quality of the one or more generated signals from the in vivo analyte sensor, and to convert the one or more generated signals from the in vivo analyte sensor into a corresponding one or more analyte concentration level based on the calibration measurement if the quality of the calibration measurement and the quality of the one or more generated signals from the in vivo analyte sensor are suitable for calibration.

2. The system of claim 1, wherein the data processing element is configured to determine a sensitivity based on the quality of the one or more signals from the in vivo analyte sensor and the quality of the calibration measurement.

3. The system of claim 2, wherein the sensitivity is an unweighted sensitivity factor.

4. The system of claim 2, wherein the sensitivity is an adjusted weighted factor.

5. The system of claim 2, wherein the sensitivity is a weighted sensitivity.

6. The system of claim 1, wherein the in vivo analyte sensor is a glucose sensor.

7. The system of claim 6, wherein the in vivo glucose sensor comprises a sensing element that comprises a glucose responsive enzyme.

8. The system of claim 7, wherein the sensing element comprises a hydrophilic portion.

9. The system of claim 1, wherein the data processing element is configured to perform one or more routines associated with a first calibration event of the in vivo analyte sensor at least approximately one hour after subcutaneously positioning the in vivo analyte sensor.

10. The system of claim 9, wherein the data processing element is configured to perform one or more routines associated with a second calibration event at least approximately two hours after the first calibration event.

11. The system of claim 1, wherein the data processing element device comprises a hand-held display module.

12. The system of claim 1, wherein the data processing element is configured to evaluate whether the calibration measurement is within a predetermined range of analyte concentration to determine the quality of the calibration measurement.

13. The system of claim 12, wherein the predetermined range comprises about 60 mg/dL to about 350 mg/dL.

14. The system of claim 1, wherein the blood sample for the calibration measurement is less than about 1 microliter.

15. The system of claim 1, wherein the blood sample for the calibration measurement is less than about 0.5 microliters.

16. The system of claim 1, wherein the blood sample for the calibration measurement is less than about 0.2 microliters.

17. The system of claim 1, wherein the calibration site is an arm.

18. The system of claim 1, wherein the calibration site is an abdomen.

19. The system of claim 1, wherein the quality of the generated one or more signals from the in vivo analyte sensor comprises evaluating whether the one or more signals is within a predetermined rate of change of the one or more signals from the in vivo analyte sensor.

20. The system of claim 1, wherein the calibration sensor is an in vitro sensor.

21. The system of claim 1, wherein the calibration sensor is an in vivo calibration sensor.

22. The system of claim 1, wherein the in vivo analyte sensor is a transcutaneous sensor.