SYSTEMS AND METHODS FOR REPLACING SIGNAL ARTIFACTS IN A GLUCOSE SENSOR DATA STREAM

• US 20120203467A1
• Filed: 04/04/2012
• Published: 08/09/2012
• Est. Priority Date: 08/22/2003
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Kamath, Apurv, Brauker, James H., Mahalingam, Aarthi, Li, Ying
• Granted Patent: US 9,510,782 B2
• Time in Patent Office: Days
• US Class Current: 702/19
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• 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 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14539 for measuring pH
• 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 5/6848 Needles
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: A61B 5/7239 using differentiation including higher order derivatives
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• 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 minimizing or eliminating transient non-glucose related signal noise due to non-glucose rate limiting phenomenon such as interfering species, ischemia, pH changes, temperatures changes, known or unknown sources of mechanical, electrical and/or biochemical noise, and the like. The system monitors a data stream from a glucose sensor and detects signal artifacts that have higher amplitude than electronic or diffusion-related system noise. The system processes some or the entire data stream continually or intermittently based at least in part on whether the signal artifact event has occurred.

Claims

1. A method for estimating an analyte value from a continuous analyte sensor, the method comprising

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

evaluating the data stream;

estimating at least one analyte value for a future time period based on the data stream; and

wherein the estimating is based on the evaluation.

2. The method of claim 1, wherein the evaluating comprises evaluating a rate of change.

3. The method of claim 1, wherein the evaluating comprises performing a first derivative analysis or a second derivative analysis.

4. The method of claim 1, wherein the evaluating comprises determining a level of confidence.

5. The method of claim 1, wherein the estimating is not performed responsive to the evaluation failing a criterion.

6. The method of claim 1, wherein the evaluating comprises determining a residual associated with the data stream.

7. The method of claim 1, wherein the estimating comprises post-processing the data stream.

8. A system for estimating an analyte value from a continuous analyte sensor, the system comprising

a sensor data receiving module configured to receive a data stream from the continuous analyte sensor for a time period;

a processor module configured to evaluate the data stream and estimate at least one analyte value for a future time period based on the data stream based on the evaluation.

9. The system of claim 8, wherein the processor module evaluates the data stream by determining a rate of change of the data stream.

10. The system of claim 8, wherein the processor module evaluates the data stream by performing a first derivative analysis or a second derivative analysis.

11. The system of claim 8, wherein the processor module is configured to determine a level of confidence associated with the data stream.

12. The system of claim 8, wherein the processor module is configured to not estimate the at least one analyte value when the evaluation fails a criterion.

13. The system of claim 8, wherein the processor module is configured to determine a residual associated with the data stream.

14. The system of claim 8, wherein the processor module is configured to post-process the data stream.