An artificial pancreas (AP) is a control system for automatic insulin delivery. The investigators have implemented a high blood sugar detection and dosing algorithm for use within an AP control system. If a high blood sugar pattern is detected, correction insulin will be calculated and delivered. The investigators will test how well the new algorithm manages glucose compared to the AP control system without high blood sugar detection and dosing. This type of algorithm may improve glucose control for high risk patient populations.
Participants will be on study for approximately 4 weeks. During the study, participants will wear an Omnipod to deliver insulin. Participants will also wear a Dexcom G6 CGM. The CGM system will send sensed glucose data every 5 minutes wirelessly via Bluetooth Low Energy (BTLE) to an Android smartphone running the iPancreas app. The closed-loop system will receive activity data through an activity watch worn by the participant. Participants will complete system training on Day 1 in clinic and then spend the rest of the 4 weeks under free-living conditions. The first 3 weeks of the study will be the training period when the system will collect patterns from the glucose sensor, insulin, and fitness data that lead to high blood sugar. After the 3-week training period, participants will complete a virtual visit to train the participant on the high blood sugar detection and dosing algorithm, then continue to use for an additional week. Participants will complete meal and exercise challenges.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
TREATMENT
Masking
NONE
Enrollment
10
The Model Predictive Control (MPC) insulin infusion algorithm contains a model within the controller that takes as an input the aerobic metabolic expenditure in addition to the CGM and meal in puts. The algorithm uses heart rate and accelerometer data collected on the patient's body to calculate metabolic expenditure (METs). The METs then acts on the model for the insulin dynamics, whereby more energy expenditure and longer duration exercise can lead to a more substantial effect of insulin on the CGM. The MPC also has missed meal insulin bolus detection where the system will calculate the amount of insulin that was missed for a meal. The missed meal boluses can be delivered automatically without any input from the user. This feature can also be disabled. The MPC has a new feature called hyperglycemia pattern detection and dosing algorithm that will analyze problem patterns associated with high blood sugar and automatically calculate and deliver a correction dose.
Oregon Health and Science University
Portland, Oregon, United States
RECRUITINGPercent of time with sensor glucose less than 70 mg/dl
Assess the percent of time that the Dexcom G6 reported sensor glucose values less than 70 mg/dl comparing first 3 weeks vs. last week
Time frame: entire 4 week study
Percent of time with sensor glucose less than 54 mg/dl
Assess the percent of time that the Dexcom G6 reported sensor glucose values less than 54 mg/dl comparing first 3 weeks vs. last week
Time frame: entire 4 week study
Percent of time the pattern evaluation windows occurred
To assess the hyperglycemia pattern detection and dosing feature by evaluating the percent time that the feature is active in detecting hyperglycemic patterns during the pattern evaluation windows calculated as: (minutes in pattern evaluation window) / (total minutes) \* 100
Time frame: entire 4 week study
Percent of time with sensor glucose greater than 250 mg/dl
Assess the percent of time that the Dexcom G6 reported sensor glucose values more than 250 mg/dl comparing first 3 weeks vs. last week
Time frame: entire 4 week study
Percent of time with sensor glucose 70 to 180 mg/dl
Assess the percent of time that the Dexcom G6 reported sensor glucose values between 70-180 mg/dl comparing first 3 weeks vs. last week
Time frame: entire 4 week study
Percent of time with sensor glucose 70 to 140 mg/dl
Assess the percent of time that the Dexcom G6 reported sensor glucose values between 70-140 mg/dl comparing first 3 weeks vs. last week
Time frame: entire 4 week study
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Percent of time with sensor glucose greater than 180 mg/dl
Assess the percent of time that the Dexcom G6 reported sensor glucose values more than 180 mg/dl
Time frame: entire 4 week study
Coefficient of variation of glucose
Assess the coefficient of variation of sensor glucose reported from the Dexcom G6 CGM comparing first 3 weeks vs. last week
Time frame: entire 4 week study
Insulin delivered
Assess the insulin delivered in units/kg/day comparing first 3 weeks vs. last week
Time frame: entire 4 week study
Hypoglycemia treatments
Assess the number of hypoglycemia treatments (counted as 15 grams of oral carbohydrate) per day comparing first 3 weeks vs. last week
Time frame: entire 4 week study