The effects of administration of small doses of insulin in correction of metabolic derangements of alloxan-diabetic rabbits

The effects of administration of small doses of soluble insulin have been observed on 18 alloxan-diabetic rabbits. Nine of them were treated with continuous intravenous infusion of insulin at a dose of 0.09 U/kg/hr. (intravenous group), and the remaining 9 were treated with hourly intramuscular injection of 0.22 U/kg of insulin (intramuscular group). Another 9 diabetic rabbits without receiving insulin therapy served as controls (control group). Pretreatment serum insulin levels were 2-3 μU/ml or less for all groups. Mean (± S.D.) plasma glucose values were 343 ± 104, 442 ± 62 and 430 ± 75 mg%, serum potassium 3.30 ± 0.33, 3.33 ± 0.42 and 3.44 ± 0.39 mEq/L, and plasma acetoacetate 1.11 ± 0.19, 1.33 ± 1.05 and 1.16 ± 0.57 mg% (normal value 0.74 ± 0.17 mg%), respectively, for the control, intravenous and intramuscular groups. By 4 hours of treatment, values were mean serum insulin 18.8 ± 7.4 and 42.1 ± 26.4 μU/ml, plasmaglucose 188 ± 81 and 155 ± 100 mg%, and serum potassium 2.93 ± 0.40 and 2.82 ± 0.35 mEq/L, respectively, for the intravenous and intramuscular groups; and by 6 hours of treatment, plasma glucose declined to 123 ± 54 and 120 ± 71 mg%, and serum potassium to 2.60 ± 0.34 and 2.50 ± 0.35 mEq/L, respectively, for both groups. In both groups with treatment, mild ketonemia remained unchanged throughout experimental periods. The control group showed little change of plasma glucose, a mild decrease of serum potassium and a slight aggravation of ketonemia. Despite lower insulin doses, and thus lower serum insulin levels in the intravenous group, the fall of plasma glucose was nearly the same as that of the intramuscular group. The former also showed less prominent hypokalemia. Preliminary results on 4 patients with hyperglycemic hyperosmolar nonketotic coma and two patients with diabetic ketoacidosis treated with continuous infusion of small doses of insulin were impressive. It seems that low dose insulin infusion is an appealing alternative to currently used complex yet often unsatisfactory insulin regimens for diabetic coma.