Efficacy of subcutaneous insulin lispro versus continuous intravenous regular insulin for the treatment of patients with diabetic ketoacidosis

Purpose To compare the efficacy and safety of subcutaneous insulin lispro with that of a standard low-dose intravenous infusion protocol of regular insulin in patients with uncomplicated diabetic ketoacidosis. Methods In this prospective, randomized open trial, 20 patients treated with subcutaneous insulin lispro were managed in regular medicine wards (n = 10) or an intermediate care unit (n = 10), while 20 patients treated with the intravenous protocol were managed in the intensive care unit. Patients treated with subcutaneous lispro received an initial injection of 0.3 unit/kg followed by 0.1 unit/kg/h until correction of hyperglycemia (blood glucose levels <250 mg/dL), followed by 0.05 to 0.1 unit/kg/h until resolution of diabetic ketoacidosis (pH ≥7.3, bicarbonate ≥18 mEq/L). Patients treated with intravenous regular insulin received an initial bolus of 0.1 unit/kg, followed by an infusion of 0.1 unit/kg/h until correction of hyperglycemia, then 0.05 to 0.1 unit/kg/h until resolution of diabetic ketoacidosis. Results Mean (± SD) admission biochemical parameters in patients treated with subcutaneous lispro (glucose: 674 ± 154 mg/dL; bicarbonate: 9.2 ± 4 mEq/L; pH: 7.17 ± 0.10) were similar to values in patients treated with intravenous insulin (glucose: 611 ± 264 mg/dL; bicarbonate: 10.6 ± 4 mEq/L; pH: 7.19 ± 0.08). The duration of treatment until correction of hyperglycemia (7 ± 3 hours vs. 7 ± 2 hours) and resolution of ketoacidosis (10 ± 3 hours vs. 11 ± 4 hours) in patients treated with subcutaneous lispro was not different than in patients treated with intravenous regular insulin. There were no deaths in either group, and there were no differences in the length of hospital stay, amount of insulin until resolution of diabetic ketoacidosis, or in the rate of hypoglycemia between treatment groups. Treatment of diabetic ketoacidosis in the intensive care unit was associated with 39% higher hospitalization charges than was treatment with subcutaneous lispro in a non–intensive care setting ($14,429 ± $5243 vs. $8801 ± $5549, P<0.01). Conclusion Treatment of adult patients who have uncomplicated diabetic ketoacidosis with subcutaneous lispro every hour in a non–intensive care setting may be safe and more cost-effective than treatment with intravenous regular insulin in the intensive care unit.