Transcutaneous analyte sensor

• US 8,170,803 B2
• Filed: 03/10/2005
• Issued: 05/01/2012
• Est. Priority Date: 07/13/2004
• Status: Active Grant

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Kamath, Apurv Ullas, Brauker, James, Dobbles, J. Michael
• Primary Examiner(s): Moran, Marjorie
• Assistant Examiner(s): Riggs, II, Larry D
• Application Number:
  US11/077,740
• Publication Number:
  US 20060036141A1
• Time in Patent Office: 2,609 Days
• Field of Search: None
• US Class Current: 702/19
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61B 2017/3492 against the outside of the body
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 2560/045 with a separable interface unit, e.g. for communication
• CPC Class Codes: A61B 2560/063 Devices specially adapted for delivering implantable medical measuring apparatus
• CPC Class Codes: A61B 2562/18 Shielding or protection of sensors from environmental influences, e.g. protection from mechanical damage
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/0004 characterised by the type of physiological signal transmitted
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: A61B 5/14 Devices for taking samples of blood hypodermic syringes A61M5/00; Measuring characteristics of blood in vivo, e.g. gas concentration within the blood, pH-value of blood measuring of blood pressure A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/1411 by percutaneous method, e.g. by lancet
• 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 5/14503 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 Class Codes: A61B 5/14507 specially adapted for measuring characteristics of body fluids other than blood devices for taking samples of body liquids A61B10/0045
• CPC Class Codes: A61B 5/1451 for interstitial fluid
• CPC Class Codes: A61B 5/14514 using means for aiding extraction of interstitial fluid, e.g. microneedles or suction
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 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 5/14735 : comprising an immobilised reagent
• CPC Class Codes: A61B 5/1486 : using enzyme electrodes, e.g. with immobilised oxidase
• 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 5/150022 : for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/6801 : specially adapted to be attached to or worn on the body surface
• CPC Class Codes: A61B 5/6833 : Adhesive patches
• CPC Class Codes: A61B 5/68335 : including release sheets or liners
• CPC Class Codes: A61B 5/6848 : Needles
• CPC Class Codes: A61B 5/6849 : in combination with a needle set
• CPC Class Codes: A61B 5/72 : Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: A61M 2005/1585 : Needle inserters
• CPC Class Codes: A61M 5/14244 : adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/1723 : using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• 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

The present invention relates generally to systems and methods for measuring an analyte in a host. More particularly, the present invention relates to systems and methods for evaluating sensor data from a continuous analyte sensor including receiving first and second sensor data points from the continuous analyte sensor and comparing the first and second sensor data points to determine a presence or an absence of aberrant data.

Claims

1. A method for evaluating sensor data from a continuous glucose sensor, the method comprising:

receiving sensor data from the continuous glucose sensor for a first time period;

performing signal estimation on the sensor data to provide estimated sensor data;

determining, using an electronic device, a presence of one or more aberrant data values in the sensor data by comparing one or more sensor data values to the estimated sensor data for the first time period; and

communicating sensor data for the first time period to a user in response to determining a presence of less than a first predetermined number of aberrant data values, or communicating estimated sensor data for the first time period to a user in response to determining a presence of more than a second predetermined number of aberrant data values.

2. The method of claim 1, wherein communicating sensor data comprises transmitting the sensor data to an external device and displaying the sensor data on the external device, and wherein communicating estimated sensor data comprises transmitting the estimated sensor data to the external device and displaying the estimated sensor data on the external device.

3. The method of claim 2, wherein the external device comprises at least one of a computer, a telecommunications device, or an infusion device.

4. The method of claim 1, wherein communicating sensor data comprises displaying a graphical representation associated with the sensor data.

5. The method of claim 4, wherein displaying a graphical representation comprises displaying a directional trend associated with the sensor data.

6. The method of claim 5, wherein displaying a graphical representation further comprises displaying a numeral associated with the sensor data.

7. The method of claim 1, wherein communicating comprises displaying events.

8. The method of claim 1, wherein performing signal estimation comprises filtering the sensor data.

9. The method of claim 1, wherein determining a presence of one or more aberrant data values is performed periodically.

10. The method of claim 1, wherein determining a presence of one or more aberrant data values is performed intermittently.

11. The method of claim 1, further comprising converting at least one of the sensor data or the estimated sensor data.

12. The method of claim 1, wherein the sensor data comprises integrated data.

13. The method of claim 12, wherein the integrated data is provided by a current measurement integrated over a time period.

14. The method of claim 12, wherein the integrated data is provided by a charge counting device.

15. The method of claim 1, wherein the sensor data is generated by the continuous glucose sensor during a first time period and wherein comparing the sensor data and the estimated sensor data is performed continuously for the first time period.

16. The method of claim 1, wherein performing signal estimation comprises filtering the sensor data using at least one of an IIR or FIR filter.

17. The method of claim 1, wherein the sensor data comprises one or more time spaced data points.

18. The method of claim 1, further comprising filtering the sensor data or the estimated sensor data, wherein filtering comprises adaptively filtering the sensor data or the estimated sensor data in response to the one or more aberrant data values.

19. The method of claim 1, wherein the aberrant data values are inaccurate or unreliable.

20. The method of claim 1, wherein the comparing comprises evaluating a residual of the sensor data and the estimated data.

21. The method of claim 1, wherein the compared sensor data comprises uncalibrated sensor data and the compared estimated sensor data comprises uncalibrated estimated sensor data.

22. The method of claim 21, wherein the communicated sensor data comprises calibrated sensor data and the communicated estimated sensor data comprises calibrated estimated sensor data.

23. The method of claim 21, wherein the communicated sensor data comprises uncalibrated sensor data and the communicated estimated sensor data comprises uncalibrated estimated sensor data.

24. The method of claim 1, wherein the compared sensor data comprises calibrated sensor data and the compared estimated sensor data comprises calibrated estimated sensor data.

25. The method of claim 1, wherein communicating the sensor data comprises one or more of transmitting sensor data to an external device or displaying information indicative of the sensor data value or values on a display screen.

26. The method of claim 1, wherein communicating the estimated sensor data comprises one or more of transmitting the estimated sensor data to an external device or displaying information indicative of the estimated sensor data value or values on a display of an electronic device.