SYSTEM AND METHODS FOR PROCESSING ANALYTE SENSOR DATA

• US 20100185065A1
• Filed: 03/26/2010
• Published: 07/22/2010
• Est. Priority Date: 08/01/2003
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Brauker, James H., Carr-Brendel, Victoria, Kamath, Apurv U., Goode, Paul V. JR.
• Granted Patent: US 8,428,679 B2
• Time in Patent Office: Days
• US Class Current: 600/309
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• 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

Abstract

Systems and methods for processing sensor analyte data, including initiating calibration, updating calibration, evaluating clinical acceptability of reference and sensor analyte data, and evaluating the quality of sensor calibration. During initial calibration, the analyte sensor data is evaluated over a period of time to determine stability of the sensor. The sensor may be calibrated using a calibration set of one or more matched sensor and reference analyte data pairs. The calibration may be updated after evaluating the calibration set for best calibration based on inclusion criteria with newly received reference analyte data. Fail-safe mechanisms are provided based on clinical acceptability of reference and analyte data and quality of sensor calibration. Algorithms provide for optimized prospective and retrospective analysis of estimated blood analyte data from an analyte sensor.

Claims

1. A method for analyzing data from an analyte sensor, the method comprising:

receiving data from the analyte sensor, the data comprising at least one sensor data point;

receiving reference data from a reference analyte monitor, the reference data comprising at least one reference data point; and

determining an acceptability of the sensor data or the reference data by subjecting the reference data and substantially time-corresponding sensor data to a boundary test utilizing boundaries.

2. The method of claim 1, wherein the boundaries are derived from prior information.

3. The method of claim 2, wherein the prior information comprises information obtained from at least one of in vivo testing of at least one analyte sensor and in vivo use of at least one analyte sensor.

4. The method of claim 1, further comprising a step of determining acceptability of the reference data, wherein a positive determination of acceptability is determined when the reference data and substantially time-corresponding sensor data fall within the boundaries of the boundary test.

5. The method of claim 4, further comprising using the reference data for calibration of the analyte sensor in response to a positive determination of acceptability.

6. The method of claim 4, further comprising requesting additional reference data in response to a negative determination of acceptability.

7. The method of claim 6, further comprising determining acceptability of the additional reference data, wherein a positive determination of acceptability is determined when the additional reference data and substantially time-corresponding sensor data fall within the boundaries of the boundary test.

8. The method of claim 7, further comprising using the additional reference data for calibration of the analyte sensor in response to a positive determination of acceptability of the additional reference data.

9. The method of claim 7, further comprising using the reference data for calibration of the analyte sensor if the additional reference data substantially corresponds to the reference data.

10. A system for analyzing data from an analyte sensor, the system comprising:

a sensor data receiving module configured to receive sensor data from the analyte sensor, the sensor data comprising at least one sensor data point;

a reference data receiving module configured to receive reference data from a reference analyte monitor, the reference data comprising at least one reference data point; and

a processor module configured to determine an acceptability of the sensor data or the reference data by subjecting the reference data and substantially time-corresponding sensor data to a boundary test utilizing boundaries.

11. The system of claim 10, wherein the boundaries are derived from prior information.

12. The system of claim 11, wherein the prior information comprises information obtained from at least one of in vivo testing of at least one analyte sensor and in vivo use of at least one analyte sensor.

13. The system of claim 10, wherein the processor module is configured to determine an acceptability of the reference data, wherein a positive determination of acceptability is determined when the reference data and substantially time-corresponding sensor data fall within the boundaries of the boundary test.

14. The system of claim 13, wherein the processor module is configured to use the reference data for calibration of the analyte sensor in response to a positive determination of acceptability.

15. The system of claim 13, wherein the processor module is configured to request additional reference data in response to a negative determination of acceptability.

16. The system of claim 15, wherein the processor module is configured to determine acceptability of the additional reference data, wherein a positive determination of acceptability is determined when the additional reference data and substantially time corresponding sensor data fall within the boundaries of the boundary test.

17. The system of claim 16, wherein the processor module is configured to use the additional reference data for calibration of the analyte sensor in response to a positive determination of acceptability of the additional reference data.

18. The system of claim 16, wherein the processor module is configured to use the reference data for calibration of the analyte sensor if the additional reference data substantially corresponds to the reference data.

19. A system for analyzing data from an analyte sensor, the system comprising:

a sensor data receiving module configured to receive sensor data from the analyte sensor, the sensor data comprising at least one sensor data point;

a reference data receiving module configured to receive reference data from a reference analyte monitor, the reference data comprising at least one reference data point; and

a processor module configured to perform outlier detection on the reference data or the sensor data, wherein the processor module is further configured to calibrate the analyte sensor.

20. The system of claim 19, wherein the processor module is configured to calibrate the analyte sensor after the system has successfully passed outlier detection.

21. The system of claim 19, wherein outlier detection comprises comparing reference data and time-corresponding sensor data to a boundary test.

22. The system of claim 19, wherein the processor module is configured to detect noise in the sensor signal.

23. The system of claim 22, wherein the processor module is configured to calibrate the analyte sensor only when noise is substantially not detected in the sensor signal.