SYSTEM AND METHOD FOR SENSOR RECALIBRATION

• US 20080039822A1
• Filed: 08/22/2007
• Published: 02/14/2008
• Est. Priority Date: 12/30/2003
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Shah, Rajiv, Wang, Lu, Zhang, Yanan
• Granted Patent: US 8,777,852 B2
• Time in Patent Office: Days
• US Class Current: 604/891.1
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/4839 combined with drug delivery

Abstract

An implantable sensing system that includes a sensor for sensing a biological parameter, a processor connected to the sensor for processing the parameter and a drug delivery unit connected to the processor for responding to the processor based on the parameter. The processor is programnmed to adjust an output of the sensor by compiling an array of data relating to the sensor, adjusting a sensor parameter a first time based on data in the array, adjusting a curve representing the sensor output based on data in the array and adjusting the sensor parameter a second time based on data in the array.

Claims

1. An implantable sensing system comprising:

a sensor for sensing a biological parameter;

a processor connected to the sensor for processing the parameter; and

a drug delivery unit connected to the processor for responding to the processor based on the parameter,

wherein the processor is programmed to adjust an output of the sensor by

compiling an array of data relating to the sensor;

adjusting a sensor parameter a first time based on data in the array;

adjusting a curve representing the sensor output based on data in the array; and

adjusting the sensor parameter a second time based on data in the array.

2. The system of claim 1, wherein the sensor is a glucose sensor.

3. The system of claim 1, wherein the drug delivery unit is an insulin pump.

4. The system of claim 1, wherein the insulin pump delivers insulin in response to the sensed parameter.

5. The system of claim 1, wherein compiling an array comprises compiling historical data.

6. The system of claim 5, wherein the historical data comprises measured blood glucose readings.

7. The system of claim 1, wherein compiling an array comprises compiling recent data.

8. The system of claim 7, wherein the recent data comprises glucose electrode readings and oxygen electrode readings.

9. The system of claim 7, wherein the recent data comprises measured blood glucose concentrations.

10. The system of claim 1, wherein adjusting a sensor parameter a first time comprises adjusting a nominal glucose current.

11. The system of claim 1, wherein adjusting the curve representing the sensor output comprises performing a linear regression on data in the array.

12. The system of claim 1, wherein adjusting the curve representing the sensor output comprises adjusting the curve in a piecewise linear fashion.

13. A sensor calibration system comprising:

means for compiling an array of data relating to the sensor;

means for adjusting a sensor parameter a first time based on data in the array;

means for adjusting a curve representing the sensor output based on data in the array; and

means for adjusting the sensor parameter a second time based on data in the array.