System and methods for processing analyte sensor data for sensor calibration

• US 10,617,336 B2
• Filed: 06/28/2019
• Issued: 04/14/2020
• Est. Priority Date: 03/10/2005
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Kamath, Apurv Ullas, Brauker, James H., Goode, Jr., Paul V., Mahalingam, Aarthi, Pryor, Jack
• Primary Examiner(s): Natnithithadha, Navin
• Application Number:
  US16/457,692
• Publication Number:
  US 20190320954A1
• Time in Patent Office: 291 Days
• Field of Search: 600309, 600345-366
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• 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 5/1451 for interstitial fluid
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/14735 comprising an immobilised reagent
• 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: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

Systems and methods for processing sensor analyte data are disclosed, including initiating calibration, updating calibration, evaluating clinical acceptability of reference and sensor analyte data, and evaluating the quality of sensor calibration. The sensor can be calibrated using a calibration set of one or more matched sensor and reference analyte data pairs. Reference data resulting from benchtop testing an analyte sensor prior to its insertion can be used to provide initial calibration of the sensor data. Reference data from a short term continuous analyte sensor implanted in a user can be used to initially calibrate or update sensor data from a long term continuous analyte sensor.

Claims

1. A method for calibrating a transcutaneous glucose sensor, comprising:

receiving sensor data from the transcutaneous glucose sensor by an electronics module operably connected to the transcutaneous glucose sensor, wherein the sensor data is indicative of a glucose concentration in a host;

receiving predetermined calibration information, wherein the predetermined calibration information comprises predetermined baseline information and predetermined sensitivity information associated with the transcutaneous glucose sensor; and

calibrating, using a processor module, the transcutaneous glucose sensor based on the predetermined calibration information, wherein the calibrating is performed without reference data from a reference glucose monitor.

2. The method of claim 1, wherein the predetermined baseline information is derived from in vivo testing of at least one other transcutaneous glucose sensor.

3. The method of claim 1, wherein the calibrating is based on a conversion function comprising a sensitivity value and a baseline value, and wherein the method further comprises validating the conversion function based on at least one of the predetermined baseline information or the predetermined sensitivity information.

4. The method of claim 3, further comprising determining an error if the validation fails.

5. The method of claim 3, further comprising requesting reference data if the validation fails.

6. The method of claim 3, further comprising adjusting the conversion function if the validation fails.

7. The method of claim 6, wherein adjusting the conversion function comprises adjusting the baseline value of the conversion function.

8. The method of claim 7, wherein adjusting the baseline value is based on the predetermined baseline information.

9. The method of claim 1, wherein the predetermined sensitivity information is derived from in vitro testing and provided as a calibration code.

10. A system for calibrating a transcutaneous glucose sensor, comprising:

the transcutaneous glucose sensor configured to provide sensor data indicative of a glucose concentration in a host; and

a processor module configured to calibrate the sensor data based on predetermined calibration information, wherein the predetermined calibration information comprises one or both of predetermined baseline information and predetermined sensitivity information associated with the transcutaneous glucose sensor, wherein the processor module is configured to calibrate the sensor data without reference data from a reference glucose monitor.

11. The system of claim 10, wherein the predetermined baseline information is derived from in vivo testing of at least one other transcutaneous glucose sensor.

12. The system of claim 10, wherein the calibration is based on a conversion function comprising a baseline value and a sensitivity value, and wherein the processor module is configured to validate the conversion function based on at least one of the predetermined sensitivity information or the predetermined baseline information.

13. The system of claim 12, wherein the processor module is configured to detect an error if the validation fails.

14. The system of claim 12, wherein the processor module is configured to request reference data if the validation fails.

15. The system of claim 12, wherein the processor module is configured to adjust the conversion function if the validation fails.

16. The system of claim 15, wherein the processor module is configured to adjust the conversion function by adjusting the baseline value of the conversion function.

17. The system of claim 10, wherein the calibration is based on a conversion function comprising a baseline value and a sensitivity value, and wherein the processor module is configured to adjust the baseline value based on the predetermined baseline information.

18. The system of claim 10, wherein the predetermined sensitivity information is derived from in vitro testing and provided as a calibration code.

19. The system of claim 10, further comprising:

a transmitter unit configured to operably connect to the transcutaneous glucose sensor, the transmitter unit having a radio frequency transmitter configured to wirelessly transmit sensor data; and

a receiver unit comprising a radio frequency receiver and a display, the radio frequency receiver configured to receive the transmitted sensor data and the display configured to display information based on the transmitted sensor data.

20. The system of claim 19, wherein the processor module is incorporated in the transmitter unit, wherein the processor module is configured to calibrate the sensor data prior to the sensor data being transmitted by the radio frequency transmitter.