PATIENT-CONTROLLED PORTABLE INSULIN INFUSION PUMP IN DIABETICS

Ten patients with unstable insulin-dependent diabetes mellitus, mean duration 17.5 yr, all treated with highly purified porcine NPH insulin twice daily, were placed on highly purified porcine regular insulin subcutaneously four times daily for 2 days. Thereafter a preplanned intravenous insulin infusion was given for 54 h. Insulin in an amount corresponding to 24-h insulin requirement was infused by a portable infusion pump. Immediately before the main meals the prandial infusion program was released by the patients by pushing a button. Capillary blood glucose was taken every 30 min during the day and every 2 h during the night. Endogenous insulin secretion was calculated by measuring the C-peptide rsponse after 1 mg of glucagon intravenously. Insulin antibodies were measured in all patients. Insulin antibody concentration was low in most cases, and only one patient reacted to glucagon by a significant but low rise of C-peptide. After an equilibration period of 5 h, mean blood glucose (MBG) was in the physiologic range in 6 of 10 patients during the infusion period. MGB in the 10 diabetics averaged 5.5 ± 1.0 mmol/L (Mean ± SD) compared with 4.4 ± 0.4 mmol/L in nondiabetic controls. The mean amplitude of glycemic excursions (MAGE) was 4.1 ± 1.4 mmol/L (mean ± SD) against 1.8 ± 0.6 mmol/L in control subjects. MBG, MAGE, and glucosuria were significantly reduced on the infusion days compared with the days on subcutaneous insulin. It is concluded that near-normal blood glucose fluctuations can be obtained in unstable diabetics by a preplanned prandial insulin infusion program activated by diabetic patients themselves.