iLet Bionic Pancreas System User Guide

Key vocabulary terms, device components, and clinical safety concepts from the iLet Bionic Pancreas System User Guide.

iLet Bionic Pancreas System

An insulin delivery system that automatically regulates blood glucose (BG) levels using autonomous lifelong learning to calculate, deliver, and adapt insulin doses to changing needs.

iLet ACE Pump

An alternate controller enabled pump intended to deliver insulin under the skin based on input from an integrated continuous glucose monitor (iCGM) and an interoperable automated glycemic controller (iAGC).

iLet Dosing Decision Software

A set of mathematical formulas comprising basal, bolus correction, and meal announcement algorithms that calculate and predict insulin needs based on CGM values and trends.

iLet Cartridge

A sterile glass container with a soft membrane (septum) and a red rubber plunger that holds up to $1.8\,mL$ (or $180\,units$) of insulin.

iLet Connect

A plastic Luer connector that attaches the flexible tubing of the insulin infusion set to the iLet Device.

iLet Charge

The system's power adaptor and charging components used to recharge the iLet Device's internal battery.

integrated Continuous Glucose Monitoring (iCGM)

A system, such as Dexcom G6, Dexcom G7, or Abbott FreeStyle Libre 3 Plus, that provides continuous glucose readings to the iAGC.

Interoperable Automated Glycemic Controller (iAGC)

The software component that autonomously determines and commands changes to insulin dosing based on CGM or manual blood glucose inputs.

Self-Monitoring Blood Glucose (SMBG)

A manual method of testing blood sugar using a meter, required for calibration or when CGM input is temporarily unavailable.

Hypoglycemia

A condition of low blood glucose, defined by the system's alerts as being below $75\,mg/dL$, with urgent levels below $54\,mg/dL$.

Hyperglycemia

A condition of high blood glucose, which can lead to diabetic ketoacidosis if prolonged.

Diabetic Ketoacidosis (DKA)

A life-threatening complication occurring when the body produces excess blood acids (ketones), often resulting from interrupted insulin delivery.

BG-Run Mode

A limited dosing mode used when the CGM is offline, requiring manual blood glucose entries to continue basal delivery and correction doses for a maximum of $48$ to $72\,hours$.

Meal Announcement

The process of informing the iLet System of an upcoming meal by selecting the type (Breakfast, Lunch, Dinner) and the carbohydrate size (Usual for me, More, Less).

Limited Access

An optional, user-settable passcode feature ($4$ to $8\,digits$) designed to prevent accidental touches or unauthorized access to device settings and meal announcements.

Occlusion

A blockage or air bubble in the tubing or infusion set that interrupts the delivery of insulin.

Insulin On Board (IOB)

A measurement found in Algorithm Steps showing the amount of active insulin currently in the user's body.

IPX8

The moisture ingress protection rating for the iLet Device, indicating it is protected against immersion in water for up to $12\,feet$ for $30\,minutes$.

MR Unsafe

A safety designation indicating the iLet System presents a projectile hazard and must remain outside of the procedure room during Magnetic Resonance Imaging.

Hydroxyurea (Hydrea)

A medication used for blood disorders and cancer that is contraindicated for iLet users because it can cause falsely elevated sensor glucose readings.

Basal Insulin Algorithm

The specific algorithm that calculates the baseline insulin dose the user should always receive, even if no glucose value is available.

Bolus Correction Algorithm

The software component that adjusts the basal dose to account for factors like stress or sleep and prevents insulin stacking.

Always On Display

A feature that allows the display to provide basic status information after $45\,seconds$ of inactivity, though the touchscreen remains locked.