1171 CONTINUOUS INTRAVENOUS INSULIN DELIVERY IN AMBULATORY ADOLESCENT DIABETICS

Abstract

Devices and methods for long term intravenous insulin infusion in ambulatory patients have recently been developed. With informed consent we studied 7 non-obese uncomplicated Type I diabetics (aged 15-17y) who received insulin for 14-23 days by central venous infusion (CVII). All subjects were studied in hospital with otherwise unrestricted activity and received 3 daily meals and an evening snack of constant caloric content. Under local anesthesia, a thin silicone rubber catheter was inserted into a branch of the external jugular vein, advanced to the SVC and tunnelled subcutaneously to exit in the supramammary region, where it was connected to the portable system consisting of a small peristaltic pump, a flow rate controller and a reservoir of soluble insulin. Insulin was infused at a constant basal rate of 17±3 mU/min. The rate was increased 15 minutes from the start of a meal 4-5 fold for 60-120 min then returned to the basal rate in a 2 step fashion over 40-120 min. Fasting plasma glucose (mean±SEM) was 262±40 prior to infusion and fell to 92±9 mg/dl on CVII with increases during mealtimes from 80±3 to 115±3 mg/dl at 41±3 min pc. Mean urinary glucose excretion of 55 g/day fell to 1.9 during CVII and fasting serum cholesterol of 220±28 and triglycerides of 281±94 fell to 138±13 and 115±24 mg/dl respectively. Mean HgbAl (N:6.5 - 8.5%) fell from 14.8 to 10.7% by the end of the study period. All indices of control showed improvement with p <0.05. There were no catheter related complications and the system was well accepted by all subjects. We conclude that in ambulatory adolescent diabetics continuous central venous insulin infusion without continuous glucose sensing is feasible for the prolonged normalization of glycemia and other indices of metabolic control.