Advanced analyte sensor calibration and error detection

Patent metadata

Field	Value
Publication number	US-2016018246-A1
Application number	US-201514860392-A
Country	US
Kind code	A1
Filing date	Sep 21, 2015
Priority date	Apr 15, 2011
Publication date	Jan 21, 2016
Grant date	—

Abstract

Systems and methods for processing sensor data and self-calibration are provided. In some embodiments, systems and methods are provided which are capable of calibrating a continuous analyte sensor based on an initial sensitivity, and then continuously performing self-calibration without using, or with reduced use of, reference measurements. In certain embodiments, a sensitivity of the analyte sensor is determined by applying an estimative algorithm that is a function of certain parameters. Also described herein are systems and methods for determining a property of an analyte sensor using a stimulus signal. The sensor property can be used to compensate sensor data for sensitivity drift, or determine another property associated with the sensor, such as temperature, sensor membrane damage, moisture ingress in sensor electronics, and scaling factors.

First claim

1 - 33 . (canceled)

34 . A method for determining a defective sensor, the method comprising:
generating sensor data using a continuous analyte sensor; generating, using sensor electronics, analyte concentration values using the sensor data generated by the continuous analyte sensor; determining an impedance of the continuous analyte sensor; and determining that the sensor is defective based on the determined impedance.

35 . The method of claim 34 , wherein determining the impedance of the continuous analyte sensor is performed iteratively.

36 . The method of claim 34 , wherein determining the impedance of the continuous analyte sensor is performed in substantially real time.

37 . The method of claim 34 , wherein impedance is determined by electrochemical impedance spectroscopy.

38 . The method of claim 34 , further comprising determining a sensitivity of the continuous analyte sensor during sensor use.

39 . The method of claim 38 , wherein determining the sensitivity is performed in substantially real time.

40 . The method of claim 38 , wherein determining the sensitivity of the continuous analyte sensor is performed iteratively.

41 . The method of claim 40 , wherein determining the sensitivity of the continuous analyte sensor is performed throughout a substantially entire sensor session.

42 . The method of claim 34 , wherein the determined impedance is compared to an established impedance-to-sensor sensitivity relationship.

43 . The method of claim 42 , further comprising determining sensor sensitivity by using the impedance-to-sensor sensitivity relationship.

44 . The method of claim 42 , further comprising determining a change in sensitivity over time by using the impedance-to-sensor sensitivity relationship.

45 . The method of claim 34 , wherein the defective sensor is detected by an unstable sensor sensitivity.

Assignees

• Dexcom Inc

Inventors

• Bohm Sebastian
• Rong Daiting
• Simpson Peter C

Classifications

• A61B5/14503

  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 title

• A61B5/1473

  invasive, e.g. introduced into the body by a catheter · CPC title

• G01N33/49

  Blood {(chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80)} · CPC title

• A61B5/14517

  for sweat · CPC title

• A61B5/14546

  for measuring analytes not otherwise provided for, e.g. ions, cytochromes · CPC title