SIGNAL PROCESSING FOR CONTINUOUS ANALYTE SENSOR

• US 20090062635A1
• Filed: 11/03/2008
• Published: 03/05/2009
• Est. Priority Date: 12/09/2003
• Status: Abandoned Application

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Brauker, James H., Carr-Brendel, Victoria, Goode, Paul V., Kamath, Apurv U., Thrower, James P., Xavier, Ben
• Application Number:
  US12/263,993
• Publication Number:
  US 20090062635A1
• Time in Patent Office: Days
• US Class Current: 600/365
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• 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 5/1468 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 5/1486 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: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/7455 characterised by tactile indication, e.g. vibration or electrical stimulation
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick
• 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: G16Z 99/00 Subject matter not provided for in other main groups of this subclass
• 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 dynamically and intelligently estimating analyte data from a continuous analyte sensor, including receiving a data stream, selecting one of a plurality of algorithms, and employing the selected algorithm to estimate analyte values. Additional data processing includes evaluating the selected estimative algorithms, analyzing a variation of the estimated analyte values based on statistical, clinical, or physiological parameters, comparing the estimated analyte values with corresponding measure analyte values, and providing output to a user. Estimation can be used to compensate for time lag, match sensor data with corresponding reference data, warn of upcoming clinical risk, replace erroneous sensor data signals, and provide more timely analyte information encourage proactive behavior and preempt clinical risk.

Claims

1. A method for processing and displaying sensor data from a continuous analyte sensor, the method comprising:

receiving sensor data from a continuous analyte sensor for a time period;

calculating a rate of change of the sensor data for the time period; and

displaying an arrow on a user interface that represents an amplitude and a direction of the rate of change of the sensor data for the time period, wherein the arrow has a rotational direction with at least 45 degrees of resolution.

2. The method of claim 1, further comprising calibrating the sensor data to obtain calibrated sensor data, wherein the step of calculating a rate of change is performed on the calibrated sensor data.

3. The method of claim 1, wherein the step of displaying comprises displaying a graphical representation of the sensor data and a numerical representation of the sensor data.

4. The method of claim 1, wherein the step of displaying comprises displaying one or more clinical risk zones.

5. The method of claim 4, wherein the clinical risk zone is represented by at least one of a line, a shaded region, a colored region, and a patterned region.

6. The method of claim 1, wherein the step of displaying comprises displaying one or more target analyte values.

7. The method of claim 6, further comprising determining a therapy recommendation associated with the one or more target analyte values, wherein the step of displaying comprises displaying a representation of the therapy recommendation.

8. The method of claim 1, further comprising calibrating the sensor data, wherein the step of displaying comprises displaying a range of values representative of a variation of a calibrated sensor data value.

9. The method of claim 1, wherein the step of displaying comprises displaying at least one of a predicted analyte value and a range of predicted analyte values.

10. The method of claim 1, wherein the analyte sensor is a glucose sensor.

11. A system for processing and displaying sensor data from a continuous analyte sensor, the system comprising:

an input module configured to receive sensor data from a continuous analyte sensor for a time period; and

a processor module configured to calculate a rate of change of the sensor data for the time period, wherein the processor module is further configured to display an arrow on a user interface, wherein the arrow represents an amplitude and a direction of the rate of change of the sensor data for the time period, wherein the arrow has a rotational direction with at least 45 degrees of resolution.

12. The system of claim 11, wherein the processor module is further configured to calibrate the sensor data to obtain calibrated sensor data, wherein the rate of change calculation is performed on the calibrated sensor data.

13. The system of claim 11, wherein the processor module is further configured to display a graphical representation of the sensor data and a numerical representation of the sensor data.

14. The system of claim 11, wherein the processor module is further configured to display at least one clinical risk zone.

15. The system of claim 14, wherein the clinical risk zone is represented by at least one of a line, a shaded region, a colored region, and a patterned region.

16. The system of claim 11, wherein the processor module is configured to display one or more target analyte values.

17. The system of claim 16, wherein the processor module is configured to determine a therapy recommendation associated with the one or more target analyte values, and wherein the processor module is further configured to display a representation of the therapy recommendation.

18. The system of claim 11, wherein the processor module is further configured to calibrate the sensor data, and wherein the processor module is further configured to display a range of values representative of a variation of a calibrated sensor data value.

19. The system of claim 11, wherein the processor module is further configured to display at least one of a predicted analyte value and a range of predicted analyte values.

20. A method for processing and displaying sensor data from a continuous analyte sensor, the method comprising:

receiving sensor data from a continuous analyte sensor for a time period;

calibrating the sensor data;

calculating a rate of change of the sensor data for the time period; and

simultaneously displaying representations of first order, second order, and third order information associated with the calibrated sensor data.

21. The method of claim 20, wherein the representation of first order calibrated sensor data comprises a numerical representation of the calibrated sensor data.

22. The method of claim 21, wherein the representation of second order sensor data comprises an arrow on a user interface that represents an amplitude and a direction of the rate of change of the calibrated sensor data for the time period.

23. The method of claim 22, wherein the arrow has a rotational direction with at least 45 degrees of resolution.

24. The method of claim 22, wherein the representation of third order sensor data comprises a graphical representation of the calibrated sensor data for the time period.

25. The method of claim 20, further comprising displaying a clinical risk zone.

26. The method of claim 20, further comprising displaying one or more target analyte values.