Glucose sensor signal stability analysis

Patent metadata

Field	Value
Publication number	US-10429395-B2
Application number	US-201514796995-A
Country	US
Kind code	B2
Filing date	Jul 10, 2015
Priority date	Jun 23, 2010
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

Disclosed are methods, apparatuses, etc. for glucose sensor signal stability analysis. In certain example embodiments, a series of samples of at least one sensor signal that is responsive to a blood glucose level of a patient may be obtained. Based at least partly on the series of samples, at least one metric may be determined to assess an underlying trend of a change in responsiveness of the at least one sensor signal to the blood glucose level of the patient over time. A reliability of the at least one sensor signal to respond to the blood glucose level of the patient may be assessed based at least partly on the at least one metric assessing the underlying trend. Other example embodiments are disclosed herein.

First claim

What is claimed is:

1. A method comprising:
obtaining a series of samples of at least one sensor signal that is responsive to a blood glucose level of a patient wherein the at least one sensor signal is generated by a glucose sensor during a time that the glucose sensor is in contact with the patient;
determining, using the series of samples and using one or more processors, at least one metric assessing an underlying trend of a change in responsiveness of the at least one sensor signal to the blood glucose level of the patient over time;
assessing a reliability of the at least one sensor signal to respond to the blood glucose level of the patient using the at least one metric assessing the underlying trend and using the one or more processors; and
in response to the assessing the reliability of the at least one sensor signal, altering an infusion treatment for the patient, or transmitting notification to the patient or a healthcare provider indicative of the reliability of the at least one sensor signal,
wherein the assessing the reliability of the at least one sensor signal comprises comparing the at least one metric with at least a first predetermined threshold and a second predetermined threshold,
wherein the at least one sensor signal is assessed to not be drifting or the at least one sensor is assessed to be stable, or both, if an absolute value of the underlying trend is less than the first predetermined threshold,
wherein the at least one sensor signal is assessed to be drifting or the at least one sensor is assessed to be unstable, or both, if the absolute value of the underlying trend is between the first and second predetermined thresholds,
wherein the at least one sensor is assessed to be dying, if the absolute value of the underlying trend is greater than the second predetermined threshold, and
wherein the determining of the at least one metric assessing the underlying trend comprises determining the at least one metric using a slope of a linear regression that is derived at least partly from the series of samples of the at least one sensor signal.

2. A method comprising:
obtaining a series of samples of at least one sensor signal that is responsive to a blood glucose level of a patient wherein the at least one sensor signal is generated by a glucose sensor during a time that the glucose sensor is in contact with the patient;
transforming the series of samples of the at least one sensor signal to derive a monotonic curve;
determining, using the series of samples and using one or more processors, at least one metric assessing an underlying trend of a change in responsiveness of the at least one sensor signal to the blood glucose level of the patient over time;
assessing a reliability of the at least one sensor signal to respond to the blood glucose level of the patient using the at least one metric assessing the underlying trend and using the one or more processors; and
in response to the assessing the reliability of the at least one sensor signal, altering an infusion treatment for the patient, or transmitting notification to the patient or a healthcare provider indicative of the reliability of the at least one sensor signal,
wherein the assessing the reliability of the at least one sensor signal comprises comparing the at least one metric with at least a first predetermined threshold and a second predetermined threshold,
wherein the at least one sensor signal is assessed to not be drifting or the at least one sensor is assessed to be stable, or both, if an absolute value of the underlying trend is less than the first predetermined threshold,
wherein the at least one sensor signal is assessed to be drifting or the at least one sensor is assessed to be unstable, or both, if the absolute value of the underlying trend is between the first and second predetermined thresholds,
wherein the at least one sensor is assessed to be dying, if the absolute value of the underlying trend is greater than the second predetermined threshold, and
wherein the determining of the at least one metric assessing the underlying trend comprises determining the at least one metric using a slope of a linear regression that is derived at least partly from the monotonic curve.

3. A method comprising:
obtaining a series of samples of at least one sensor signal that is responsive to a blood glucose level of a patient wherein the at least one sensor signal is generated by a glucose sensor during a time that the glucose sensor is in contact with the patient;
determining, using the series of samples and using one or more processors, at least one metric assessing an underlying trend of a change in responsiveness of the at least one sensor signal to the blood glucose level of the patient over time;
assessing a reliability of the at least one sensor signal to respond to the blood glucose level of the patient using the at least one metric assessing the underlying trend and using the one or more processors; and
in response to the assessing the reliability of the at least one sensor signal, altering an infusion treatment for the patient, or transmitting notification to the patient or a healthcare provider indicative of the reliability of the at least one sensor signal,
wherein the assessing the reliability of the at least one sensor signal comprises comparing the at least one metric with at least a first predetermined threshold and a second predetermined threshold,
wherein the at least one sensor signal is assessed to not be drifting or the at least one sensor is assessed to be stable, or both, if an absolute value of the underlying trend is less than the first predetermined threshold,
wherein the at least one sensor signal is assessed to be drifting or the at least one sensor is assessed to be unstable, or both, if the absolute value of the underlying trend is between the first and second predetermined thresholds,
wherein the at least one sensor is assessed to be dying, if the absolute value of the underlying trend is greater than the second predetermined threshold, and
wherein the determining of the at least one metric assessing the underlying trend comprises determining the at least one metric by iteratively updating a trend estimation at multiple samples of the series of samples of the at least one sensor signal based at least partly on a trend estimation at a previous sample and a growth term.

4. A method comprising:
obtaining a series of samples of at least one sensor signal that is responsive to a blood glucose level of a patient wherein the at least one sensor signal is generated by a glucose sensor during a time that the glucose sensor is in contact with the patient;
determining, using the series of samples and using one or more processors, at least one metric assessing an underlying trend of a change in responsiveness of the at least one sensor signal to the blood glucose level of the patient over time;
assessing a reliability of the at least one sensor signal to respond to the blood glucose level of the patient using the at least one metric assessing the underlying trend and using the one or more processors; and
in response to the assessing the reliability of the at least one sensor signal, altering an infusion treatment for the patient, or transmitting notification to the patient or a healthcare provider indicative of the reliability of the at least one sensor signal,
wherein the assessing the reliability of the at least one sensor signal comprises comparing the at least one metric with at least a first predetermined threshold and a second predetermined threshold,
wherein the at least one sensor signal is assessed to not be drifting or the at least one sensor is assessed to be stable, or both, if an absolute value of the underlying trend is less than the first predetermined threshold,
wherein the at least one sensor signa

Assignees

• Medtronic Minimed Inc

Inventors

• Luo Ying
• Gottlieb Rebecca K
• Ramachandran Meena
• Chiu Chia-Hung
• Dangui-Patel Nandita
• Kremliovsky Michael
• Rose Jefferson

Classifications

• A61B5/1473 Primary

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

• A61B5/0017

  transmitting optical signals · CPC title

• A61B5/7207

  of noise induced by motion artifacts · CPC title

• A61B5/002

  Monitoring the patient using a local or closed circuit, e.g. in a room or building (A61B5/0017 takes precedence) · CPC title

• G01N33/66 Primary

  involving blood sugars, e.g. galactose · CPC title