Converting U-500 regular insulin to insulin detemir and insulin lispro in a patient undergoing dietary changes in preparation for bariatric surgery.

PURPOSE: The safe and effective conversion of human regular U-500 insulin (U-500R) to basal and bolus U-100 (insulin detemir and insulin lispro, respectively) in a patient undergoing a significant dietary change in preparation for bariatric surgery is described.

SUMMARY: Conversion from U-100 to U-500R insulin has been described in the literature. There is, however, a paucity of information describing the reverse conversion (i.e., from U-500R to U-100 insulin). Whether converting to or from U-500R, patient safety is a primary concern. A 51-year-old Caucasian woman with a 10-year history of type 2 diabetes mellitus, hypertension, and gastroparesis who was scheduled to undergo bariatric surgery was converted from U-500R to insulin detemir and insulin lispro preoperatively while undergoing significant diet changes. The patient's blood glucose values, diet, and activity levels were closely monitored daily by the interprofessional team over a 10-day preoperative period during which her regular diet was changed to a very low-calorie, high-protein diet; insulin doses were adjusted accordingly. Throughout this process, the patient did not experience any major hypoglycemic episodes. Close collaboration among interprofessional team members and a strong partnership with the patient were considered key factors in the successful conversion of insulin therapy.

CONCLUSION: Subcutaneous insulin therapy in a woman preparing for bariatric surgery was safely converted from U-500R to basal therapy with U-100 insulin detemir and with as-needed boluses of U-100 insulin lispro. This occurred as the patient switched from a regular diet to a low-calorie, high-protein diet.