Abstract
In order to assess the effects of continuous subcutaneous insulin infusion (CSII) on the control of plasma glucose and on the plasma levels of other metabolites in diabetes mellitus, a portable, battery-driven infusion pump was used for 4 days in 6 insulin dependent diabetic patients (including one depancreatized, one brittle type and one with pregnancy in the 3rd trimester). The pump can deliver undiluted regular insulin at 32 speeds ranging from 1 μl/hr to 29.6 μl/hr, leaving wide choice for a given basal infusion rate. Manual operation of the pump is also possible for a bolus infusion of prescribed units before meals. In this study a bolus infusion with appropriate dosage was added before each meal in every patient.
The mean 24-hr plasma glucose level (± S.D.) of 123±28 mg/dl on CSII treatment was significantly smaller than the level of 180 ± 22 mg/dl on conventional treatment although a smaller dosage of insulin was required in the former. The M value was also significantly improved from 73± 23 to 28±9 by CSII treatment. In 3 patients whose diabetic controls were very difficult, the 24-hr plasma glucose profile and M value were almost normalized by CSII treatment with a lower frequency of hypoglycemic episodes.
The 24-hr plasma NEFA profile tended to be normalized by CSII treatment. Fasting blood ketone bodies also showed a tendency to decline towards normal levels (beta-OH butyrate: from 150± 152 μM to 85±36 μM, acetoacetate: from 66 ± 54 μM to 44±16 μM). The serum cholesterol, triglyceride and p-lipoprotein levels remained unchanged after CSII treatment. The blood alanine, pyruvate, lactate, and erythrocyte 2, 3-diphosphoglycerate concentrations were unchanged from those on conventional treatment.
In one patient possessing no insulin antibody, the 24-hr plasma IRI profile was determined, It revealed a lower level than that on conventional treatment. This may reflect a decrease in exogenous insulin used and a slightly reduced secretion of endogenous insulin (estimated from the plasma CPR profile) compared with those in conventional treatment. Even in this case, the plasma glucose control was improved by CSII treatment.
In conclusion, our easily usable CSII treatment is considered to be very effective from improving glucose metabolism in insulin dependent diabetics, especially unstable ones. It thus provides a promising means for long-term routine therapy in insulin dependent diabetics to prevent diabetic complications.
