Closed loop control system with safety parameters and methods

• US 10,173,007 B2
• Filed: 02/13/2013
• Issued: 01/08/2019
• Est. Priority Date: 10/23/2007
• Status: Active Grant

• Current Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Diabetes Care Incorporated (Abbott Laboratories)
• Inventors: Hayter, Gary Alan, Taub, Marc Barry, Bernstein, Daniel Milfred, Sloan, Mark Kent
• Primary Examiner(s): Mehta, Bhisma
• Assistant Examiner(s): Zhang, Jenna
• Application Number:
  US13/766,644
• Publication Number:
  US 20130218126A1
• Time in Patent Office: 2,155 Days
• Field of Search: 604 65- 67, 6048901, 604503-505
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 2205/8212 with means or measures taken for minimising energy consumption
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/16831 Monitoring, detecting, signalling or eliminating infusion flow anomalies low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066
• 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: G16H 20/10 relating to drugs or medications, e.g. for ensuring correct administration to patients
• CPC Class Codes: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

Methods, system and devices for monitoring a plurality of parameters associated with a closed loop control operation including continuously monitoring a physiological condition and automatic administration of a medication, detecting an adverse condition associated with the monitored physiological condition or the medication administration deviating from a predetermined safety level of the closed loop control operation, and initiating a non-zero pre-programmed medication delivery rate are provided.

Claims

1. A method comprising:

monitoring, using one or more processors, a plurality of parameters associated with a physiological condition and an administration of a medication, including monitoring a sensor signal representative of a glucose level;

detecting a potential hypoglycemic condition associated with the physiological condition;

determining a severity level associated with the potential hypoglycemic condition, including determining a rate of change in glucose level based on previously received glucose levels stored in a memory in response to a detected communication failure from a transmitter of an analyte monitoring unit, and wherein the severity level is based at least in part on a retrieved preset safety level information;

providing a hypoglycemic alert associated with the determined severity level if the sensor signal is determined to be within a dropout tolerance level;

maintaining a medication delivery rate of the monitored administration of the medication, if the determined severity level does not exceed a preset safety level; and

initiating a fixed pre-programmed medication delivery rate when the potential hypoglycemic condition is detected if the determined severity level exceeds the preset safety level, wherein the fixed pre-programmed medication delivery rate is within a previously determined safety level and different than the medication delivery rate of the monitored administration of the medication.

2. The method of claim 1, wherein the fixed pre-programmed medication delivery rate includes an automated shut off of the administration of the medication for a predetermined time period.

3. The method of claim 2, wherein the fixed pre-programmed medication delivery rate is terminated when the glucose level exceeds a predetermined level.

4. The method of claim 1, wherein the monitored plurality of parameters further includes insulin administration level, exercise level, glucose sensor signal condition, signal transmission level, or one or more combinations thereof.

5. The method of claim 1, wherein detecting the potential hypoglycemic condition includes:

retrieving the preset safety level information;

confirming the detected potential hypoglycemic condition is a hypoglycemic condition; and

automatically disabling the administration of the medication.

6. The method of claim 1, wherein the sensor signal is provided by an in vivo analyte sensor.

7. The method of claim 6, wherein the in vivo analyte sensor comprises a plurality of electrodes including a working electrode, wherein the working electrode comprises an analyte-responsive enzyme and a mediator, wherein at least one of the analyte-responsive enzyme and the mediator is chemically bonded to a polymer disposed on the working electrode, and wherein at least one of the analyte-responsive enzyme and the mediator is crosslinked with the polymer.

8. The method of claim 1, wherein the sensor signal is determined to be within the dropout tolerance level by determining a degree of uncertainty in the sensor signal based on a predicted or anticipated glucose level.

9. The method of claim 8, wherein the medication is insulin, and the glucose level is predicted or anticipated based at least in part on a parameter associated with insulin on board information, glucose rate of change information, or amount of insulin delivered.

10. The method of claim 1, wherein detecting the potential hypoglycemic condition further comprises determining a rate of change in an analyte level, and wherein the hypoglycemic alert is further associated with the determined rate of change in the analyte level.

11. An apparatus, comprising:

one or more processors; and

a memory for storing instructions which, when executed by the one or more processors, cause the one or more processors to monitor a plurality of parameters associated with a physiological condition and an administration of a medication, including a sensor signal representative of a glucose level, to detect a potential hypoglycemic condition associated with the physiological condition, to determine a severity level associated with the potential hypoglycemic condition including determining a rate of change in glucose level based on previously received glucose levels stored in a memory in response to a detected communication failure from a transmitter of an analyte monitoring unit wherein the severity level is based at least in part on a retrieved preset safety level information, to provide a hypoglycemic alert associated with the determined severity level if the sensor signal is determined to be within a dropout tolerance level, to maintain a medication delivery rate of the monitored administration of the medication if the determined severity level does not exceed a preset safety level, and to initiate a fixed pre-programmed medication delivery rate when the adverse condition is detected if the determined severity level exceeds a preset safety level, wherein the fixed pre-programmed medication delivery rate is within a previously determined safety level and different than the medication delivery rate of the monitored administration of medication.

12. The apparatus of claim 11, wherein the fixed preprogrammed medication delivery rate includes an automated shut off of the administration of the medication for a predetermined time period.

13. The apparatus of claim 12, wherein the fixed preprogrammed medication delivery rate is terminated when the monitored glucose level exceeds a predetermined level.

14. The apparatus of claim 11, wherein the monitored plurality of parameters further includes insulin administration level, exercise level, glucose sensor signal condition, signal transmission level, or one or more combinations thereof.

15. The apparatus of claim 11, wherein the instructions, when executed by the one or more processors, cause the one or more processors to retrieve the preset safety level information, confirm the detected potential hypoglycemic condition as a hypoglycemic condition, and automatically disable the administration of medication.

16. The apparatus of claim 11, further comprising an in vivo analyte sensor.

17. The apparatus of claim 16, wherein the in vivo analyte sensor comprises a plurality of electrodes including a working electrode, wherein the working electrode comprises an analyte-responsive enzyme and a mediator, wherein at least one of the analyte-responsive enzyme and the mediator is chemically bonded to a polymer disposed on the working electrode, and wherein at least one of the analyte-responsive enzyme and the mediator is crosslinked with the polymer.

18. The apparatus of claim 11, wherein the sensor signal is determined to be within the dropout tolerance level by using a predicted or anticipated glucose level to determine a degree of uncertainty in the sensor signal.

19. The apparatus of claim 18, wherein the medication is insulin, and the glucose level is predicted or anticipated based at least in part on a parameter associated with insulin on board information, glucose rate of change information, or amount of insulin delivered.