PMC8116592_01
Graph showing an overview of the patient's glycemic control the week prior to the episode. Directly taken from the patient's personal record on the hybrid closed-loop system's manufacturer's site.
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F1
HCL system (Medtronic 670G  in auto-mode) for 9 months, had improved metabolic control since its use (estimated HbA1c 7.3% and average blood glucose 162 +- 68 mg/dl; Figure 1), felt very comfortable with the device, and both the patient and the parents were reluctant to interrupt it (the system's program details are shown in Supplementary Table 1). His ratios and sensitivities had been programmed in his last visit according to the patient's glycemic response to prandial insulin, but this does not affect basal insulin administration since the basal rates are not altered by this program when the system runs in auto-mode.
Overview of the glucose levels along the episode. Arrows point to the following events: (1) admission at the emergency room, (2) overnight fast, (3 and 4) laparoscopic appendectomy, and (5) initiating oral tolerance. Open circles reflect blood glucose calibrations.
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F2
The system infused a total of 82 micro-boluses of 0.11 IU of insulin on average (range, 0.03-0.13; Figure 2:overnight fast). The system also spent a total time of 1 h and 15 min without administering any micro-bolus. The mean dose of these boluses was 0.089 IU of insulin (range, 0.05-0.13), and the glucose levels were always within range (Figure 2:laparoscopic appendectomy). We then decided to begin oral tolerance (3 h post-surgery; Figure 2), resulting in a hyperglycemic peak (maximum, 280 mg/dl) since no prandial insulin bolus had been administered, and dextrose fluid had not been discontinued.