SYSTEM AND METHODS FOR PROCESSING ANALYTE SENSOR DATA

• US 20080183399A1
• Filed: 04/04/2008
• Published: 07/31/2008
• Est. Priority Date: 08/01/2003
• Status: Abandoned Application

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Brauker, James H., Goode, Paul V., Kamath, Apurv U.
• Application Number:
  US12/098,353
• Publication Number:
  US 20080183399A1
• Time in Patent Office: Days
• US Class Current: 702/22
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 2560/04 Constructional details of apparatus
• CPC Class Codes: A61B 2562/085 combined with means for recording calibration data
• CPC Class Codes: A61B 3/10 Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/1433 provided with locking means details of syringes A61M5/315
• 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 5/14865 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 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/743 Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots
• CPC Class Codes: G01N 33/48707 by electrical means G01N33/49, G01N33/493 take precedence
• 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, 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 validating of at least one of reference glucose data and sensor glucose data, the method comprising:

receiving sensor data from a continuous glucose sensor, the sensor data comprising one or more sensor data points;

receiving reference data from a reference glucose monitor, the reference data comprising one or more reference data points; and

validating at least one of the one or more sensor data points and the one or more reference data points.

2. The method of claim 1, further comprising a step of accepting one or more reference data points as a valid entry, wherein the step of validating is performed prior to the step of accepting one or more sensor or reference data points as a valid entry.

3. The method of claim 1, further comprising a step of accepting one or more reference data points for use in calibration of the continuous glucose sensor, wherein the step of validating is performed prior to the step of accepting one or more reference data points for use in calibration.

4. The method of claim 1, wherein the step of validating comprises determining if the one or more sensor or reference data points are physiologically feasible based on one or more previous sensor or one or more previous reference data points.

5. The method of claim 4, wherein physiologically feasibility is based on at least one of a maximum rate of change of glucose concentration in a host and a maximum acceleration of glucose concentration in a host.

6. The method of claim 1, wherein the step of validating is based on at least one of environmental information and physiological information.

7. The method of claim 6, wherein the environmental information or physiological information comprises information selected from the group consisting of time of day, oxygen concentration, postural effects, and patient-entered environmental data.

8. The method of claim 1, wherein the step of validating is based on a determination of oxygen concentration.

9. The method of claim 1, further comprising a step of predicting future glucose values, wherein the step of validating comprises comparing a current glucose value to a time corresponding predicted glucose value.

10. A system for validating of at least one of reference glucose data and sensor glucose data, the system comprising:

a sensor data module configured to receive sensor data from a continuous glucose sensor, the sensor data comprising one or more sensor data points;

a reference input module configured to receive reference data from a reference glucose monitor, the reference data comprising one or more reference data points; and

a processor module configured to validate at least one of the one or more sensor data points and the one or more reference data points.

11. The system of claim 10, wherein the processor module is further configured to accept at least one of one or more sensor data points and one or more reference data points as a valid entry after validating at least one of the one or more sensor data points and the one or more reference data points.

12. The system of claim 10, wherein the processor module is further configured to accept one or more reference data points for calibrating after validating the one or more reference data points.

13. The system of claim 10, wherein the processor module is configured to validate the one or more sensor or reference data points by determining if at least one of the one or more sensor data points and the one or more reference data points are physiologically feasible based on at least one of one or more previous sensor data points and one or more previous reference data points.

14. The system of claim 13, wherein physiologically feasibility is based on at least one of a maximum rate of change of glucose concentration in a host and a maximum acceleration of glucose concentration in a host.

15. The system of claim 10, wherein the processor module is configured to validate at least one of the one or more sensor data points and one or more reference data points based on at least one of environmental information and physiological information.

16. The system of claim 10, wherein the environmental information or physiological information comprises information selected from the group consisting of time of day, oxygen concentration, postural effects, and patient-entered environmental data.

17. The system of claim 10, wherein the processor module is configured to validate at least one of the one or more sensor points and one or more reference data points based on a determination of oxygen concentration.

18. The system of claim 10, wherein the processor module is further configured to predict or to estimate a future one or more glucose values based on previous sensor data, and wherein the processor module is configured to validate at least one of the one or more sensor data points and the one or more reference data points by comparing a current glucose value to at least one of a time corresponding predicted glucose value or an estimated glucose value.