Abstract
Eleven brittle diabetics, mean duration 11.5 years, all treated with highly purified porcine NPH insulin twice daily, were placed on highly purified porcine regular insulin 4 times daily for 2 days. Thereafter pre-planned intravenous insulin infusion was started. Insulin in an amount corresponding to the daily insulin requirement was infused by a mobile electric infusion pump at precalculated rates between 30 and 7 ml/hour during 2 days. The patients were ambulatory. Capillary blood glucose was taken every 30 min after meals and every two hours during the night. After an equilibration period of 7 hours, blood glucose fluctuations were in the physiological range in nearly all patients during the infusion period. [Only 1.3% of the blood samples showed glucose levels lower than 2.5 mmol/l and 2.9% levels exceeding 10.0 mmol/l during the infusion days]. Mean blood glucose (MBG) was 6.0±0.9 mmol/l (mean ± s. d.), the standard deviation of MBG was 1.8±0.5 mmol/l, the mean amplitude of blood glucose excursions (MAGE) 4.7±1.4 mmol/l, and glucosuria 3.1±3.9 g/day. All these data of glucose homeostasis were significantly lower during the infusion days. The incidence of hypoglycaemic attacks was low (0.32/patient/day) and not significantly higher than during NPH treatment. It is concluded that near normal blood glucose fluctuations can be achieved in brittle diabetics by preplanned insulin infusion without `blood glucose monitoring.