Ambulatory diabetes management with pulsed subcutaneous insulin using a portable pump

A portable pump, programmed to administer intermittent pulses of insulin subcutaneously, supplemented by premeal boluses, was used by 8 patients for periods up to 12 months. Two boys, 11 and 16 years of age, sought improved growth; four young adults age 19 to 26 years desired normalization of metabolism to forestall microvascular complications already manifest; a 14-year-old girl had been incapacitated by unstable diabetes and a 26-year-old woman had been unable to attain sufficient control to gain weight without developing hypoglycemia. Maximal possible control with conventional insulin administration was attempted prior to pump use and such control was measured by glycohemoglobin (HgbA1) percentage and urine and blood sugar levels during a 24-hour period and compared with control with pump use. All initially had marked reduction in 24-hour urine volume (mean 3.3 L +/- .4 SEM to 1.4 +/- 0.2), urine glucose (mean 198 g +/- 81 to 14 +/- 4) and glycemia (mean 258 mg/dl +/- 29 to 133 +/- 12). HgbA1% declined markedly in all but the 14-year-old girl over the first weeks and reached normal or near normal levels in three patients. Four patients continued to use the pump after 3.5 to 12 months because of improved sense of well being, weight control, and in one, marked reduction in proteinuria. Both boys had a doubling of growth pace. Four patients are no longer using the pump after 3 to 8 months because of inconvenience, manipulation with intermittent usage, intolerance of normoglycemia, or overzealous control attempts with dangerous hypoglycemia. Pump use may permit the attainment of levels of control previously not possible, but is extremely demanding for patients and health personnel and must remain an experimental method in carefully selected and monitored patients.