INSULIN ON BOARD COMPENSATION FOR A CLOSED-LOOP INSULIN INFUSION SYSTEM

• US 20140066892A1
• Filed: 04/25/2013
• Published: 03/06/2014
• Est. Priority Date: 08/30/2012
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Keenan, Desmond Barry, Mastrototaro, John J., Grosman, Benyamin, Parikh, Neha J., Roy, Anirban
• Granted Patent: US 9,364,609 B2
• Time in Patent Office: Days
• US Class Current: 604/506
• 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 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• 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 2205/18 with alarm
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2205/52 with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 2205/582 by tactile feedback
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• 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 10/40 for data related to laboratory analysis, e.g. patient specimen analysis
• CPC Class Codes: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders

Abstract

An electronic controller for an insulin infusion device includes a processor architecture and at least one memory element. The memory element stores executable instructions that, when executed by the processor architecture, provide an insulin on board (IOB) compensation module to estimate a current IOB value that indicates an amount of active insulin in the body of the user, calculate an IOB rate based at least in part on the estimated current IOB value, determine an adjusted insulin infusion rate based at least in part on the calculated IOB rate and an uncompensated insulin infusion rate, select a final insulin infusion rate for the device, and provide the selected final insulin infusion rate to regulate delivery of insulin by the device.

Claims

1. An electronic device comprising:

a processor architecture comprising at least one processor device; and

at least one memory element associated with the processor architecture, the at least one memory element storing processor-executable instructions that, when executed by the processor architecture, perform a method of controlling an insulin infusion device for a user, the method comprising;

computing a current insulin on board (IOB) value that indicates an amount of active insulin in the body of the user;

calculating an IOB rate based at least in part on the computed IOB value;

determining an adjusted insulin infusion rate based at least in part on the calculated IOB rate and an uncompensated insulin infusion rate; and

selecting a final insulin infusion rate for the insulin infusion device, wherein the selecting selects either the determined adjusted insulin infusion rate, the uncompensated insulin infusion rate, or a current basal rate as the final insulin infusion rate.

2. The electronic device of claim 1, wherein the method performed by the processor-executable instructions further comprises:

communicating the selected final insulin infusion rate to regulate delivery of insulin by the insulin infusion device.

3. The electronic device of claim 1, wherein the method performed by the processor-executable instructions further comprises:

repeating the computing, the calculating, the determining, and the selecting in accordance with a predetermined schedule to adjust the final insulin infusion rate in an ongoing manner.

4. The electronic device of claim 1, wherein:

the electronic device comprises a monitor device for the insulin infusion device; and

the monitor device and the insulin infusion device are physically distinct hardware devices.

5. The electronic device of claim 1, wherein:

the electronic device comprises the insulin infusion device; and

the monitor device and the insulin infusion device are physically and functionally integrated into a single hardware device.

6. The electronic device of claim 1, wherein:

the electronic device comprises a portable wireless device; and

the portable wireless device and the insulin infusion device are physically distinct hardware devices.

7. The electronic device of claim 1, wherein the current IOB value is calculated based at least in part on historical bolus delivery data for the user.

8. The electronic device of claim 7, wherein the current IOB value is calculated in accordance with a three-compartment insulin pharmacokinetic model.

9. The electronic device of claim 7, wherein determining the adjusted insulin infusion rate comprises:

selecting the adjusted insulin infusion rate in accordance with the expression AdjustedRate(n)=max(0;

PIDRate(n)−

IOBRate(n)), wherein;

AdjustedRate(n) is the selected adjusted insulin infusion rate;

PIDRate(n) is the uncompensated insulin infusion rate; and

IOBRate(n) is the calculated IOB rate.

10. The electronic device of claim 7, wherein selecting the final insulin infusion rate comprises:

selecting the final insulin infusion rate in accordance with the expression FinalRate(n)=max(Basal;

AdjustedRate(n)) when PIDRate>

Basal, wherein;

FinalRate(n) is the selected final insulin infusion rate;

Basal is the current basal rate;

AdjustedRate(n) is the determined adjusted insulin infusion rate; and

PIDRate(n) is the uncompensated insulin infusion rate.

11. A tangible and non-transitory electronic storage medium having processor-executable instructions that, when executed by a processor architecture comprising at least one processor device, perform a method of controlling an insulin infusion device for a user, the method comprising:

estimating a current insulin on board (IOB) value that indicates an amount of active insulin in the body of the user;

calculating an IOB rate based at least in part on the estimated current IOB value;

determining an adjusted insulin infusion rate based at least in part on the calculated IOB rate and an uncompensated insulin infusion rate;

selecting a final insulin infusion rate for the insulin infusion device, wherein the selecting selects either the determined adjusted insulin infusion rate, the uncompensated insulin infusion rate, or a current basal rate as the final insulin infusion rate; and

providing the selected final insulin infusion rate to regulate delivery of insulin by the insulin infusion device.

12. The electronic storage medium of claim 11, wherein the method performed by the processor-executable instructions further comprises:

repeating the estimating, the calculating, the determining, the selecting, and the providing in accordance with a predetermined schedule to adjust the final insulin infusion rate in an ongoing manner.

13. The electronic storage medium of claim 11, wherein estimating the current IOB value is based at least in part on historical bolus delivery data for the user.

14. The electronic storage medium of claim 13, wherein the current IOB value is estimated in accordance with a three-compartment insulin pharmacokinetic model.

15. The electronic storage medium of claim 11, wherein determining the adjusted insulin infusion rate comprises:

selecting the adjusted insulin infusion rate in accordance with the expression AdjustedRate(n)=max(0;

PIDRate(n)−

IOBRate(n)), wherein;

AdjustedRate(n) is the selected adjusted insulin infusion rate;

PIDRate(n) is the uncompensated insulin infusion rate; and

IOBRate(n) is the calculated IOB rate.

16. The electronic storage medium of claim 11, wherein selecting the final insulin infusion rate comprises:

selecting the final insulin infusion rate in accordance with the expression FinalRate(n)=max(Basal;

AdjustedRate(n)) when PIDRate>

Basal, wherein;

FinalRate(n) is the selected final insulin infusion rate;

Basal is the current basal rate;

AdjustedRate(n) is the determined adjusted insulin infusion rate; and

PIDRate(n) is the uncompensated insulin infusion rate.

17. An electronic controller for an insulin infusion device, the electronic controller comprising:

a processor architecture comprising at least one processor device; and

at least one memory element associated with the processor architecture, the at least one memory element storing processor-executable instructions that, when executed by the processor architecture, provide an insulin on board compensation module to;

estimate a current insulin on board (IOB) value that indicates an amount of active insulin in the body of the user;

calculate an IOB rate based at least in part on the estimated current IOB value;

determine an adjusted insulin infusion rate based at least in part on the calculated IOB rate and an uncompensated insulin infusion rate;

select a final insulin infusion rate for the insulin infusion device, wherein the final insulin infusion rate is selected as either the determined adjusted insulin infusion rate, the uncompensated insulin infusion rate, or a current basal rate; and

provide the selected final insulin infusion rate to regulate delivery of insulin by the insulin infusion device.

18. The electronic controller of claim 17, wherein the current IOB value is estimated in accordance with a three-compartment insulin pharmacokinetic model.

19. The electronic controller of claim 17, wherein the adjusted insulin infusion rate is determined by:

selecting the adjusted insulin infusion rate in accordance with the expression AdjustedRate(n)=max(0;

PIDRate(n)−

IOBRate(n)), wherein;

AdjustedRate(n) is the selected adjusted insulin infusion rate;

PIDRate(n) is the uncompensated insulin infusion rate; and

IOBRate(n) is the calculated IOB rate.

20. The electronic controller of claim 17, wherein the final insulin infusion rate is selected by:

selecting the final insulin infusion rate in accordance with the expression FinalRate(n)=max(Basal;

AdjustedRate(n)) when PIDRate>

Basal, wherein;

FinalRate(n) is the selected final insulin infusion rate;

Basal is the current basal rate;

AdjustedRate(n) is the determined adjusted insulin infusion rate; and

PIDRate(n) is the uncompensated insulin infusion rate.