Background and Aims: Insulin infusion sets are one of the weak links in pump therapy and closed-loop systems. We conducted a randomized blinded study testing a novel infusion set which with and without heparin, hypothesizing that a small amount of heparin infused over multiple days would decrease thrombosis and inflammation around catheters.
Methods: The catheter hub with cannula was the MiniMed™ Quick-set ™ with a new tubing connector and hub. The connector was modified to contain an inert non-heparin (P) or heparin (80 units) (H) added to the P. Visibly the sets were identical and the study was double blinded. Four infusion sets (two P and two H) were worn by each subject for 7 days or until failure.
Results: 20 subjects were studied (mean age 29.5±8 years). Median (IQR) duration of wear for 40 sets with H was 6.97 (6.5, 7) days and for 40 sets with P was 6.98 (6, 7) days. There were 9 sets in each group that failed before the 6th day. The mean total daily insulin dose and mean of sensor readings between 2 AM and 6 AM did not differ between the two groups and did not change with day of wear.
Conclusions: There was no difference between the two groups with the modified caps containing either a non-heparin (placebo), or the placebo combined with heparin in overall duration of wear. Both the non-Heparin and Heparin Extended Wear infusion sets had a longer length of wear compared to historical studies using a Quick-Set.