Background: The first hybrid closed loop (HCL) system became commercially available in the U.S. in 2017, and there is no standard process for training patients. The goal of this quality improvement project was to optimize transition to HCL for pediatric patients at a large diabetes center.

Methods: Our multidisciplinary team developed a novel HCL training program, meeting monthly over 4 months to review data and refine training with a Plan-Do-Study-Act model. The HCL training plan for current insulin pump users included 1) in-person group class to reinforce conventional insulin pump and CGM use on the new system, 2) a live videoconference class to teach HCL use, 3) three follow-up phone calls in the first 6 weeks after HCL training to assess system use, make insulin adjustments, and provide targeted re-education.

Results: Seventy-two patients (age 14 ± 4.3y; 46% female) with type 1 diabetes (HbA1c 8.7 ± 1.4%) were trained over 4 months. Mean sensor wear time was 83% and HCL time was 73%. Sensor time in target range (70-180 mg/dl) increased from 49% to 62% between week 1 and week 4 (p= <.001). Sensor wear and HCL time did not change. All patients completed both classes, and 79% and 48% completed 2 and 3 follow-up calls respectively. Mean phone call time was 16 minutes. Trainers strengthened carbohydrate ratios to increase mealtime insulin doses in 75% of patients, with most changes made at breakfast (68% of patients). The most common reason for HCL exit was high sensor glucose (1.98/week). The most common topics during calls were importance of meal boluses, correction boluses for high blood glucose, and responding to system alerts to prevent HCL exits.

Conclusion: Ongoing educational support is vital in the early weeks of HCL use. Scheduled telephone contact helped address barriers and reinforce behaviors essential for success. Patients benefited from increased meal boluses in HCL compared to traditional pump mode. Future work will clarify the support necessary to optimize long- term outcomes with HCL.


C. Berget: None. S. Thomas: None. L.H. Messer: Other Relationship; Self; Medtronic MiniMed, Inc.. S. Owen: None. K. Thivener: None. R.H. Slover: None. R. Wadwa: Advisory Panel; Self; Eli Lilly and Company. Research Support; Self; MannKind Corporation, Dexcom, Inc., Xeris Pharmaceuticals, Inc., Bigfoot Biomedical. G.T. Alonso: None.

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