System and methods for processing analyte sensor data for sensor calibration

• US 10,743,801 B2
• Filed: 11/21/2019
• Issued: 08/18/2020
• 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:
  US16/691,252
• Publication Number:
  US 20200085355A1
• Time in Patent Office: 271 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 glucose monitoring system comprising:

a transcutaneous electrochemical glucose sensor having an in vivo portion and an ex vivo portion;

a memory storing calibration information derived at least in part from an empirically derived relationship between in vitro sensitivity and in vivo sensitivity for the transcutaneous electrochemical glucose sensor; and

a processor configured to calibrate data generated by the transcutaneous electrochemical glucose sensor using the stored calibration information without reliance on any reference glucose measurements made after insertion of the in vivo portion of the transcutaneous electrochemical glucose sensor.

2. The glucose monitoring system of claim 1, wherein the ex vivo portion of the transcutaneous electrochemical glucose sensor is in electrical communication with the processor.

3. The glucose monitoring system of claim 1, wherein the empirically derived relationship between in vitro sensitivity and in vivo sensitivity is based at least in part on clinical trials.

4. The glucose monitoring system of claim 1, wherein the calibration of the generated data relies at least in part on an in vitro sensitivity associated with the transcutaneous electrochemical glucose sensor, wherein the in vitro sensitivity is based at least in part on a comparison of a signal response of a plurality of transcutaneous electrochemical glucose sensors to a set of known glucose concentrations.

5. A method for calibrating data from a transcutaneous electrochemical glucose sensor, the method comprising:

receiving sensor data from the transcutaneous electrochemical glucose sensor after at least a portion of the transcutaneous electrochemical glucose sensor is inserted in a host, wherein the sensor data is indicative of a glucose concentration in the host; and

calibrating, using a processor, the sensor data received from the transcutaneous electrochemical glucose sensor,

wherein the calibrating comprises retrieving and using calibration information derived at least in part from each of in vitro testing, in vivo testing, and a relationship between in vitro sensitivity and in vivo sensitivity derived therefrom; and

,

wherein the calibrating comprises not using reference glucose concentration values obtained after insertion of the at least a portion of the transcutaneous electrochemical glucose sensor into a host.

6. The method of claim 5, wherein the relationship between in vitro sensitivity and in vivo sensitivity has been derived at least in part through an empirical process.

7. The method of claim 6, wherein the empirical process relies on data obtained from clinical trials involving a plurality of transcutaneous electrochemical glucose sensors.

8. The method of claim 6, wherein the empirical process involves calculating the in vivo sensitivity for each of the plurality of transcutaneous electrochemical glucose sensors.

9. A glucose monitoring system comprising:

a transcutaneous electrochemical glucose sensor having an in vivo portion and an ex vivo portion;

a memory storing calibration information derived at least in part from an empirically derived relationship between in vitro sensitivity and in vivo sensitivity for the transcutaneous electrochemical glucose sensor; and

an electronics unit configured to provide calibrated glucose information, wherein the electronics unit has been programmed to calibrate data generated by the transcutaneous electrochemical glucose sensor using the stored calibration information without reliance on any reference glucose measurements made after insertion of the in vivo portion of the transcutaneous electrochemical glucose sensor into a host.

10. The glucose monitoring system of claim 9, wherein the ex vivo portion of the transcutaneous electrochemical glucose sensor is in electrical communication with the processor.

11. The glucose monitoring system of claim 9, wherein the empirically derived relationship between in vitro sensitivity and in vivo sensitivity is based at least in part on clinical trials.

12. The glucose monitoring system of claim 9, wherein the calibration of the data relies at least in part on an in vitro sensitivity associated with the transcutaneous electrochemical glucose sensor, wherein the in vitro sensitivity is based at least in part on a comparison of a signal response of a plurality of transcutaneous electrochemical glucose sensors to a set of known glucose concentrations.

13. A glucose monitoring device comprising:

a memory storing calibration information for a transcutaneous electrochemical glucose sensor, wherein the calibration information is derived at least in part from an empirically derived relationship between in vitro sensitivity and in vivo sensitivity;

a processor generating calibrated glucose information, wherein the calibrated glucose information is based at least in part on applying the stored calibration information to data generated by the transcutaneous electrochemical glucose sensor, without reliance on any reference glucose measurements made after insertion of an in vivo portion of the transcutaneous electrochemical glucose sensor into a host; and

a display providing the calibrated glucose information to a user.