| Literature DB >> 35669307 |
Cari Berget1, Jennifer L Sherr2, Daniel J DeSalvo3, Ryan S Kingman4, Sheri L Stone5, Sue A Brown6, Alex Nguyen7, Leslie Barrett7, Trang T Ly7, Gregory P Forlenza1.
Abstract
Automated insulin delivery (AID) systems, which connect an insulin pump, continuous glucose monitoring system, and software algorithm to automate insulin delivery based on real-time glycemic data, hold promise for improving outcomes and reducing therapeutic burden for people with diabetes. This article reviews the features of the Omnipod 5 Automated Insulin Delivery System and how it compares to other AID systems available on or currently under review for the U.S. market. It also provides practical guidance for clinicians on how to effectively train and onboard people with diabetes on the Omnipod 5 System, including how to personalize therapy and optimize glycemia. Many people with diabetes receive their diabetes care in primary care settings rather than in a diabetes specialty clinic. Therefore, it is important that primary care providers have access to resources to support the adoption of AID technologies such as the Omnipod 5 System.Entities:
Year: 2022 PMID: 35669307 PMCID: PMC9160549 DOI: 10.2337/cd21-0083
Source DB: PubMed Journal: Clin Diabetes ISSN: 0891-8929
FIGURE 1Components of the Omnipod 5 AID system: (left) the tubeless Pod containing the AID algorithm; (center) the app, pictured running on a smartphone; and (right) the Dexcom G6 interoperable CGM sensor. The Pod is a lightweight, waterproof (IP28), self-adhesive insulin pump that delivers insulin via an automatically inserted cannula. The algorithm receives glucose measurements every 5 minutes from the on-body CGM sensor and engages the Pod to deliver microboluses every 5 minutes based on current and projected glucose levels, aiming for a set target glucose value in its calculations. Users interact with the system through the app, which communicates wirelessly with the Pod. Actions performed via the app include completing initial setup and programming pump settings, activating and deactivating Pods, starting automated mode, using the bolus calculator/delivering boluses, enabling the Activity feature, viewing insulin delivery and CGM history, responding to system alerts and alarms, checking Pod status, and adjusting pump parameters. The app home screen displays the current CGM value and trend, the amount of IOB, information about the most recent bolus, and a link to view a CGM history graph. The bolus calculator is accessed using the circular icon near the bottom of the screen. Because the algorithm runs on the Pod and the Pod and CGM are both worn on-body and communicate directly, AID can continue uninterrupted even if the handheld device containing the app is not nearby. Image used with permission. ©2020 Insulet Corp.
Comparison of Select AID Systems in the United States (24,31–33)
| AID System | Onboarding | AID Strategy | Automation Adaptivity | Adjustable Parameters | System Features |
|---|---|---|---|---|---|
| Insulet Omnipod 5 System, | Automation begins with first Pod; maximum delivery is more constrained with first Pod for safety | TDI-based insulin automation | TDI updated with every Pod change (approximately every 72 hours) | ICR, ICF, glucose targets, duration of insulin action (DIA) | |
| Medtronic MiniMed 670G/770G, | 48-Hour warm-up period with insulin delivery in manual mode required before user can activate auto mode | TDI-based insulin automation | TDI updated every 6 days at midnight | ICR, DIA | |
| t:slim X2 with Control-IQ | Weight and TDI programmed into pump before activating automation; used at onboarding to initiate automation | Adjusts pre-programmed basal rates | Actual TDI tracked by algorithm and primarily used to scale basal adjustments | ICR, ICF, basal rates | |
| Medtronic MiniMed 780G, | 48-hour warm-up period with insulin delivery in manual mode before user can activate auto mode | TDI-based insulin automation | TDI updated every 6 days at midnight | ICR, DIA, glucose target |
This system was not commercially available in the United States but was undergoing FDA review at the time of writing.
Both systems used the same AID algorithm.
Programmable Settings in the Omnipod 5 AID System
| Parameter Name | Available Settings | Description | Implications for Automated Mode |
|---|---|---|---|
| Basal Program | Up to 24 segments per basal program, from 0 units/hour to user-set maximum basal rate in 0.05-unit/hour increments | In manual mode, the Pod will deliver basal insulin at the programmed rates. | The Basal Program is only used |
| Target Glucose | Maximum of 8 segments per day from 110 to 150 mg/dL in 10-mg/dL increments | The Target Glucose is the glucose value the algorithm aims for when calculating insulin delivery and the value the bolus calculator aims for when calculating correction bolus doses. | Target Glucose is the primary parameter that affects automation. Insulin delivery will generally increase if glucose is predicted to rise above the target and decrease or suspend if glucose is predicted to fall below the target. If glucose is trending downward, insulin delivery may be decreased or suspended, even if the current glucose value is above target. If glucose is trending upward, insulin delivery may be increased, even if the current glucose value is below target. |
| Activity | Can be set for a duration of 1–24 hours | The Activity feature temporarily reduces AID. It may be used to reduce the amount of insulin delivered with exercise or in other situations in which hypoglycemia risk may be increased. | While Activity is enabled, the algorithm targets a glucose level of 150 mg/dL (instead of the programmed Target Glucose) and additionally reduces insulin delivery. To reduce insulin on board with exercise, it is best to turn on this feature 1–2 hours before the start of exercise. Keeping it activated for up to 12 hours after exercise may be useful if delayed hypoglycemia is a concern. |
| Duration of Insulin Action (DIA) | A single setting is programmed from 2–6 hours in 30-minute increments | This setting informs the pump how long a bolus is actively working to reduce glucose. It is used to calculate the IOB remaining from past meal and correction boluses. | The DIA programmed by users is only used to calculate IOB accrual from user-delivered boluses. This setting does not influence how IOB is calculated from AID; the algorithm uses its own method to determine IOB accrual from AID. When the algorithm increases insulin delivery in response to hyperglycemia, this insulin will factor into IOB and be subtracted from user-initiated boluses, in addition to the IOB from user-given boluses. As a result, correction boluses may be smaller than expected due to the additional IOB being taken into account from AID. |
| Correction Factor | Up to 8 segments per day of 1–400 mg/dL in 1-mg/dL increments | This setting informs the pump of the user’s ICF—by how many mg/dL glucose is expected to drop from the delivery of 1 unit of insulin. It is used by the system’s bolus calculator in calculating correction boluses. | The programmed ICF does not influence AID; it is only used for user-initiated correction boluses. This setting may need to be modified to improve the efficacy of user-initiated correction boluses when using the automated mode. |
| Insulin to Carb (IC) Ratio | Up to 8 segments per day of 1–150 g carbohydrate/unit of insulin in 0.1-g increments | This setting informs the bolus calculator of the user’s ICR—how many grams of carbohydrate are covered by 1 unit of insulin. It is used by the bolus calculator to calculate mealtime boluses. | A user’s ICR may need to be changed to optimize postprandial glucose control. Because the system reduces and/or suspends insulin delivery if glucose is trending down or below target, there is often little to no IOB leading up to mealtimes. With little IOB before meals, users may benefit from a stronger ICR when using an AID system compared with an MDI regimen or conventional pump therapy, in which static basal insulin infusion occurs regardless of glucose level, resulting in more pre-meal IOB. |
| Correct Above | Up to 8 segments per day from target glucose level to 200 mg/dL in 1-mg/dL increments | This setting is the glucose level at which the bolus calculator may calculate a correction dose. | This value has no influence on AID. It may be adjusted to affect user-given correction boluses. |
| Minimum Glucose for Calc | 50–70 mg/dL in 1-mg/dL increments | This setting defines a minimum glucose value at which the pump will allow use of the bolus calculator. | This setting has no influence on AID. It may be adjusted to ensure a safe glucose value when delivering a bolus. |
| Reverse Correction | On or off | When reverse correction is turned on, the bolus calculator will reduce the mealtime bolus amount when the current glucose value is below the target glucose. | When in automated mode, users may consider turning reverse correction off if glucose is often below their target at mealtime and they are experiencing post-meal hyperglycemia. Turning the reverse correction off will ensure that users receive their full bolus dose for carbohydrates. |
| Extended Bolus | On or off | Turning on this parameter will allow users to extend a bolus delivery over 0.5–8 hours when the pump is in manual mode. | Extended boluses are not available in automated mode even if the parameter is turned on in the pump settings. Extended boluses can only be given in manual mode. |
| Temp Basal | On or off | When turned on, this feature will allow users to program a temporary basal rate of delivery or to increase or decrease the programmed basal delivery by a percentage (0–100%) when in manual mode. | Temporary basal rates are not available in automated mode, even if this feature is turned on in the pump settings. Temporary basal rates can only be used in manual mode. |
| Maximum Bolus | 0.05–30 units | This setting defines the upper limit for a bolus dose. The pump will not deliver more than the maximum bolus amount programmed by a user. | The Maximum Bolus setting has no influence on AID. It is only relevant for user-delivered bolus doses. |
| Maximum Basal Rate | 0.05–30 units/hour | This setting defines the maximum basal rate the pump will allow in manual mode. Usually this is set to twice the highest user-programmed basal rate to allow for temporary basal rate increases as needed in manual mode. | The programmed Maximum Basal Rate has no impact on AID. The algorithm determines maximum delivery for each user when in automated mode. |