INFUSION DEVICES AND RELATED METHODS AND SYSTEMS FOR PREEMPTIVE ALERTING

• US 20160175520A1
• Filed: 12/19/2014
• Published: 06/23/2016
• Est. Priority Date: 12/19/2014
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Palerm, Cesar C., Myers, Jeffrey C.
• Granted Patent: US 10,307,535 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 5/7275 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: A61M 2205/18 with alarm
• 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 20/17 delivered via infusion or injection

Abstract

Infusion systems, infusion devices, and related operating methods are provided. An exemplary method of alerting a user associated with an infusion device delivering fluid to the body of the user involves obtaining a measurement value for a physiological condition being influenced by the fluid, obtaining a current amount of active fluid in the body of the user, determining a homeostasis metric based at least in part on the current amount of active fluid and the measurement value for the physiological condition, and generating an alert based at least in part on the homeostasis metric.

Claims

1. A method of alerting a user, the method comprising:

obtaining a measurement value for a physiological condition in a body of the user, the physiological condition being influenced by a fluid delivered by an infusion device;

obtaining a current amount of active fluid in the body of the user;

determining a homeostasis metric based at least in part on the current amount of active fluid and the measurement value for the physiological condition; and

generating an alert based at least in part on the homeostasis metric.

2. The method of claim 1, further comprising obtaining an amount of fluid pending delivery, wherein determining the homeostasis metric comprises determining the homeostasis metric based at least in part on the current amount of active fluid, the amount of fluid pending delivery, and the measurement value for the physiological condition.

3. The method of claim 2, further comprising obtaining a current insulin sensitivity factor for the user, wherein determining the homeostasis metric comprises determining the homeostasis metric based at least in part on the current amount of active fluid, the amount of fluid pending delivery, the current insulin sensitivity factor, and the measurement value for the physiological condition.

4. The method of claim 1, wherein:

obtaining the measurement value comprises obtaining a current measurement value of a glucose level of the user;

determining the homeostasis metric comprises determining an estimated correction bolus amount based at least in part on the current amount of active fluid and the current measurement value; and

generating the alert comprises generating a notification when the estimated correction bolus amount is greater than a threshold value.

5. The method of claim 4, further comprising:

obtaining an amount of fluid pending delivery; and

obtaining a current insulin sensitivity factor for the user, wherein determining the estimated correction bolus amount comprises determining the estimated correction bolus amount based at least in part on the current amount of active fluid, the amount of fluid pending delivery, the current insulin sensitivity factor, and the current measurement value.

6. The method of claim 5, further comprising determining the threshold value based at least in part on the current insulin sensitivity factor for the user.

7. The method of claim 4, further comprising determining a trend in the glucose level of the user based at least in part on the current measurement value, wherein determining the estimated correction bolus amount further comprises adjusting the estimated correction bolus amount based on the trend.

8. The method of claim 4, wherein generating the notification comprises displaying the estimated correction bolus amount.

9. The method of claim 1, wherein:

obtaining the measurement value comprises obtaining a reference measurement value of a glucose level of the user at a time of a bolus;

determining the homeostasis metric comprises determining an expected glucose measurement value at a subsequent time based at least in part on the current amount of active fluid and the reference measurement value; and

generating the alert comprises generating a notification based on a relationship between the expected glucose measurement value and a current measurement value of the glucose level of the user at the subsequent time.

10. The method of claim 9, further comprising:

obtaining an amount of fluid pending delivery at the subsequent time; and

obtaining a current insulin sensitivity factor for the user, wherein determining the expected glucose measurement value comprises;

determining an expected drop in the glucose level at the subsequent time based on the current insulin sensitivity factor and a difference between an amount of the bolus and a sum of the current amount of active fluid and the amount of fluid pending delivery; and

determining the expected glucose measurement value based on the expected drop and the reference measurement value.

11. The method of claim 9, further comprising determining a trend in the glucose level of the user at the time of the bolus, wherein determining the expected glucose measurement value comprises determining the expected glucose measurement value at the subsequent time based at least in part on the current amount of active fluid at the subsequent time, the reference measurement value at the time of the bolus, and the trend in the glucose level of the user at the time of the bolus.

12. The method of claim 1, wherein:

obtaining the measurement value comprises obtaining a current measurement value of a glucose level of the user;

determining the homeostasis metric comprises determining an excess insulin amount based at least in part on the current amount of active fluid and the current measurement value; and

generating the alert comprises generating a notification when the excess insulin amount is greater than a threshold value.

13. The method of claim 12, further comprising obtaining an amount of fluid pending delivery, wherein determining the excess insulin amount comprises:

determining an expected drop in the glucose level based at least in part on the current amount of active fluid, the amount of fluid pending delivery, and an insulin sensitivity factor for the user;

determining an expected glucose level based at least in part on the current measurement value and the expected drop; and

determining the excess insulin amount based at least in part on the insulin sensitivity factor and a difference between the expected glucose level and an excess insulin alert threshold.

14. The method of claim 12, further comprising determining a recommended amount of carbohydrates based on the excess insulin amount, wherein generating the notification comprises displaying the recommended amount of carbohydrates.

15. The method of claim 12, further comprising determining a recommended modification to an insulin delivery scheme based on the excess insulin amount, wherein generating the notification comprises displaying the recommended modification.

16. A computer-readable medium having computer-executable instructions stored thereon that, when executed by a processing system associated with the infusion device, cause the processing system to perform the method of claim 1.

17. An infusion system comprising:

a user interface;

an infusion device operable to deliver fluid to a body of a user, the fluid influencing a physiological condition of the user;

a sensing arrangement to obtain a measurement value for the physiological condition from the body of the user; and

a control system to obtain the measurement value from the sensing arrangement, determine a homeostasis metric based at least in part on the measurement value and a current amount of active fluid in the body of the user, and generate an alert via the user interface based at least in part on the homeostasis metric.

18. The infusion system of claim 17, the fluid comprising insulin influencing a glucose level in the body of the user, wherein:

the measurement value comprises a current measurement value of the glucose level in the body of the user; and

the homeostasis metric comprises an estimated correction bolus amount determined based at least in part on a current insulin on board for the user, the current measurement value, and a target glucose value; and

the alert comprises a graphical notification of the estimated correction bolus amount.

19. The infusion system of claim 17, the fluid comprising insulin influencing a glucose level in the body of the user, wherein:

the measurement value comprises a current measurement value of the glucose level in the body of the user;

the homeostasis metric comprises an excess insulin amount determined based at least in part on a current insulin on board for the user, the current measurement value, and a target glucose value; and

the alert comprises a graphical notification of a recommended amount of carbohydrates to offset the excess insulin amount.

20. An infusion device comprising:

a user interface;

a motor operable to deliver fluid to a body of a user, the fluid influencing a physiological condition of the user; and

a control system coupled to the motor and the user interface to;

operate the motor to deliver the fluid;

obtain a measurement value for the physiological condition in the body of the user;

determine a current amount of active fluid in the body of the user;

determine an amount of fluid pending delivery to the body of the user;

determine a homeostasis metric based at least in part on the current amount of active fluid, the amount of fluid pending delivery, and the measurement value; and

provide a notification via the user interface based at least in part on the homeostasis metric.