Method and system for providing continuous calibration of implantable analyte sensors

• US 7,885,698 B2
• Filed: 02/28/2006
• Issued: 02/08/2011
• Est. Priority Date: 02/28/2006
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories Incorporated)
• Inventors: Feldman, Benjamin J.
• Primary Examiner(s): MARMOR II, CHARLES ALAN
• Application Number:
  US11/365,340
• Publication Number:
  US 20090054748A1
• Time in Patent Office: 1,806 Days
• Field of Search: None
• US Class Current: 600/347
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 5/0017 transmitting optical signals transmission by light H04B10/00
• 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 5/0031 Implanted circuitry
• 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 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/6846 specially adapted to be brought in contact with an internal body part, i.e. invasive
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks

Abstract

Method and system for providing continuous calibration of analyte sensors includes calibrating a first sensor, receiving data associated with detected analyte levels from the first sensor, and calibrating a second sensor based on a predetermined scaling factor and data associated with detected analyte levels from the first sensor, is disclosed.

Claims

1. A method of providing continuous calibration of analyte sensors, comprising:

calibrating a first sensor using one or more processors;

receiving data associated with detected analyte levels from the first sensor; and

calibrating a second sensor with reference to one or more detected analyte levels from the first sensor using one or more processors, wherein calibrating the second sensor includes determining a scaling factor based on data from the first sensor and the second sensor, applying the scaling factor to the data from the second sensor, and determining a correlation level of data from the first sensor and from the second sensor;

wherein determining the scaling factor includes comparing the data from the first sensor with the data from the second sensor, and determining the scaling factor based on a calculated scaling factor with the lowest level of average error between the data of the first sensor and the data of the second sensor.

2. The method of claim 1 further including the step of calibrating a third sensor based on a second scaling factor and data associated with detected analyte levels from the second sensor.

3. The method of claim 1 wherein the step of calibrating the second sensor starts after a predetermined time period has passed where the first sensor has been in fluid contact with an analyte of a patient.

4. The method of claim 3 wherein the predetermined time period includes at least approximately 90% of the life of the first sensor.

5. The method of claim 3 wherein the predetermined time period includes at least approximately 50% of the life of the first sensor.

6. The method of claim 1 further including the step of determining a sensitivity of the first sensor.

7. The method of claim 1 further including the step of receiving data associated with detected analyte levels from the second sensor.

8. The method of claim 1 wherein the step of calibrating the second sensor includes the steps of:

determining an analyte level; and

comparing the determined analyte level with the data associated with the detected analyte level from the first sensor.

9. The method of claim 1 further including the step of comparing the correlation level with a predetermined correlation threshold defining an acceptable stability level of the second sensor.

10. The method of claim 1 wherein the first sensor and the second sensor are analyte sensors.

11. The method of claim 1 further including the step of removing the first sensor while retaining the second sensor in fluid contact with the analyte of a patient.

12. The method of claim 1 wherein the first sensor and the second sensor are subcutaneously positioned under a skin of a patient.

13. The method of claim 12 wherein at least a portion of the first sensor and at least a portion of the second sensor are in fluid contact with the patient'"'"'s analyte.

14. A method, comprising:

positioning a first sensor in fluid contact with an analyte of a patient;

calibrating the first sensor using one or more processors;

positioning a second sensor in fluid contact with the analyte of the patient after calibrating the first sensor;

calibrating the second sensor based on data from the first sensor using the one or more processors; and

removing the first sensor while retaining the second sensor in fluid contact;

wherein calibrating the second sensor includes determining a scaling factor based on data from the first sensor and the second sensor, applying the scaling factor to the data from the second sensor, and determining a correlation level of data from the first sensor and from the second sensor; and

further

wherein determining the scaling factor includes comparing the data from the first sensor with the data from the second sensor, and determining the scaling factor based on a calculated scaling factor with the lowest level of average error between the data of the first sensor and the data of the second sensor.

15. The method of claim 14 wherein the second sensor is subcutaneously placed in the patient after a predetermined time period has passed where the first sensor has been in fluid contact with an analyte of a patient.

16. The system of claim 15 wherein the predetermined time period includes at least approximately 90% of the life of the first sensor.

17. The system of claim 15 wherein the predetermined time period includes at least approximately 50% of the life of the first sensor.