Closed loop control of physiological glucose
The present disclosure relates to systems and methods for controlling physiological glucose concentrations in a patient.
1. A system for providing closed-loop control of physiological glucose, comprising:
a drug delivery device configured to receive a first drug reservoir containing insulin and a second drug reservoir containing glucagon;
a user interface configured to receive user input comprising exercise data;
a glucose measuring device configured to measure a current interstitial glucose; and
a controller,
wherein in response to receipt of the exercise data, the controller is configured to estimate a physiological glucose based on the measured current interstitial glucose, calculate a corrected physiological glucose by subtracting an exercise factor from the estimated physiological glucose, and based on the calculation, to cause a glucagon bolus and an insulin bolus to be delivered in a closed-loop,
wherein the glucagon bolus is deliverable only when a rate of change of the physiological glucose is less than a glucose rate threshold, and
wherein the glucose rate threshold is a function of the estimated physiological glucose.
2. The system according to claim 1 , wherein the glucose rate threshold is less than zero for the glucagon bolus to be delivered.
3. The system according to claim 1 , wherein a glucagon bolus volume or size scales with the rate of change of physiological glucose and the estimated physiological glucose.
4. The system according to claim 2 , wherein the glucagon bolus increases with decreasing rate of change of physiological glucose and/or decreasing estimated physiological glucose.
5. The system according to claim 1 , wherein the rate of change of physiological glucose is calculated as a difference between two successive estimated physiological glucose values if the estimated values are based on measurements of the current interstitial glucose at fixed intervals.
6. The system according to claim 1 , wherein doses of glucagon are set to zero or canceled for a period after a meal.
7. The system according to claim 6 , wherein the doses of glucagon are set to zero or canceled for 2 hours after the meal.
8. The system according to claim 1 , wherein the exercise factor is 3 mmol/L.
9. A system for providing closed-loop control of physiological glucose, comprising:
a drug delivery device configured to receive a first drug reservoir containing insulin and a second drug reservoir containing glucagon;
a user interface configured to receive user input comprising exercise data;
a glucose measuring device configured to measure a current interstitial glucose; and
a controller,
wherein in response to receipt of the exercise data, the controller is configured to estimate a physiological glucose based on the measured current interstitial glucose, calculate a corrected physiological glucose by subtracting an exercise factor from the estimated physiological glucose, and based on the calculation, to cause increased doses of the glucagon and doses of the insulin to be delivered in a closed-loop.
10. The system according to claim 9 , wherein the doses of glucagon are set to zero or canceled for a period after a meal.
11. The system according to claim 10 , wherein the doses of glucagon are set to zero or canceled for 2 hours after the meal.
12. The system according to claim 9 , wherein the exercise factor is 3 mmol/L.