USE OF SENSOR REDUNDANCY TO DETECT SENSOR FAILURES

• US 20140005505A1
• Filed: 03/07/2013
• Published: 01/02/2014
• Est. Priority Date: 06/29/2012
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Peyser, Thomas A., Bhavaraju, Naresh C., Bowman, Leif N., Kamath, Apurv Ullas, Mahalingam, Aarthi, Pryor, Jack, Simpson, Peter C.
• Granted Patent: US 10,881,339 B2
• Time in Patent Office: Days
• US Class Current: 600/316
• CPC Class Codes: A61B 2562/04 Arrangements of multiple sensors of the same type
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 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 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence

Abstract

Devices, systems, and methods for providing more accurate and reliable sensor data and for detecting sensor failures. Two or more electrodes can be used to generate data, and the data can be subsequently compared by a processing module. Alternatively, one sensor can be used, and the data processed by two parallel algorithms to provide redundancy. Sensor performance, including sensor failures, can be identified. The user or system can then respond appropriately to the information related to sensor performance or failure.

Claims

1. A method for detecting a sensor failure in a continuous analyte monitoring system implanted in a host, the method comprising:

receiving first sensor data from a first electrode implanted in the host, wherein the first sensor data are indicative of a property corresponding to the first electrode;

receiving second sensor data from a second electrode implanted in the host, wherein the second sensor data are indicative of the property corresponding to the second electrode, the first electrode and the second electrode having substantially same characteristics;

comparing, using a processor module, the property corresponding to the first electrode with the property corresponding to the second electrode; and

identifying a failure in at least one of the first electrode or the second electrode when a property magnitude of the first electrode is different from a property magnitude of the second electrode by a predetermined value.

2. The method of claim 1, wherein the property is sensor sensitivity to an analyte.

3. The method of claim 1, wherein the property is baseline.

4. The method of claim 1, wherein the first electrode is located substantially adjacent to the second electrode.

5. The method of claim 1, wherein the first electrode and the second electrode are separated by a distance of less than about 1 mm at a closest proximity.

6. The method of claim 1, wherein the first electrode and the second electrode are separated by a distance of less than about 0.5 mm at a closest proximity.

7. A method for detecting a sensor failure in a continuous analyte monitoring system implanted in a host, the method comprising:

receiving first sensor data over a time period from a first electrode implanted in the host, wherein the first sensor data are indicative of a property corresponding to the first electrode;

receiving second sensor data over the time period from a second electrode implanted in the host, wherein the second sensor data are indicative of the property corresponding to the second electrode, the first and second electrodes having substantially same characteristics;

determining, using a processor module, over the time period a correlation between the property corresponding to the first electrode with the property corresponding to the second electrode; and

identifying a failure in at least one of the first electrode or the second electrode when the correlation is less than a predetermined value.

8. A method for detecting a sensor failure in a continuous analyte monitoring system implanted in a host, the method comprising:

receiving first sensor data over a time period from a first electrode implanted in the host, wherein the first sensor data are indicative of a first property and a second property corresponding to the first electrode;

receiving second sensor data over the time period from a second electrode implanted in the host, wherein the second sensor data are indicative of the first property and the second property corresponding to the second electrode, the first and second electrodes having substantially same characteristics;

determining, using a processor module, a value that is representative at least in part of differences in the first and second properties between the first electrode and the second electrode over the time period; and

responding to the determination of the value when the value exceeds a predetermined threshold by at least one of deactivating a continuous analyte monitoring system, displaying an alert, instructing a user to remove a sensor comprising the first electrode and the second electrode from the host, or instructing a user to insert a new sensor comprising a new first electrode and a new second electrode in the host.

9. A method for detecting a sensor failure in a continuous analyte monitoring system implanted in a host, the method comprising:

receiving sensor data over a time period from a continuous analyte sensor implanted in the host, the sensor data comprising at least one sensor data point;

processing the at least one sensor data point using a first algorithm to determine a first analyte concentration value;

processing the at least one sensor data point using a second algorithm to determine a second analyte concentration value, wherein the first algorithm is different from the second algorithm;

comparing, using a processor module, the first analyte concentration value to the second analyte concentration value; and

identifying a sensor failure if a difference between the first analyte concentration value and the second analyte concentration value exceeds a predetermined amount.

10. A continuous analyte monitoring system, the system comprising:

an electrochemical analyte sensor configured to be implanted in a host and to generate a first signal indicative of a first concentration value of a first analyte in the host;

a fiber optic sensor configured to be implanted in the host and to generate a second signal indicative of a second concentration value of a second analyte in the host; and

a processor configured to evaluate the first concentration value and the second concentration value to determine a third concentration value.

11. The continuous analyte monitoring system of claim 10, wherein the system comprises a wire-shaped analyte measuring device, wherein the analyte measuring device comprises an elongated body comprising an elongated core, wherein the elongated core comprises at least a portion of the fiber optic sensor, and wherein the electrochemical analyte sensor is formed onto an outer surface of the elongated core.

12. The continuous analyte monitoring system of claim 10, wherein the first analyte and the second analyte are same.

13. The continuous analyte monitoring system of claim 12, wherein the first analyte and the second analyte are glucose.

14. The continuous analyte monitoring system of claim 10, wherein the first analyte and the second analyte are different.

15. A continuous analyte monitoring system configured for detecting a sensor failure when implanted in a host, the system comprising:

a first electrode configured to receive first sensor data when implanted in a host, wherein the first sensor data are indicative of a property corresponding to the first electrode;

a second electrode having substantially same characteristics as the first electrode and configured to receive second sensor data when implanted in a host, wherein the second sensor data are indicative of a property corresponding to the second electrode; and

a processor module configured to compare the property corresponding to the first electrode with the property corresponding to the second electrode and to identify a failure in at least one of the first electrode or the second electrode when a property magnitude of the first electrode is different from a property magnitude of the second electrode by a predetermined value.

16. The continuous analyte monitoring system of claim 15, wherein the property is sensor sensitivity to an analyte.

17. The continuous analyte monitoring system of claim 15, wherein the property is baseline.

18. The continuous analyte monitoring system of claim 15, wherein the first electrode is located substantially adjacent to the second electrode.

19. The continuous analyte monitoring system of claim 15, wherein the first electrode and the second electrode are separated by a distance of less than about 1 mm at a closest proximity.

20. The continuous analyte monitoring system of claim 15, wherein the first electrode and the second electrode are separated by a distance of less than about 0.5 mm at a closest proximity.

21. The continuous analyte monitoring system of claim 15, wherein the analyte is glucose.