Insulin Treatment of Special Circumstances

Insulin Treatment of Special Circumstances

A. Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA) is a life-threatening medical emer-gency caused by inadequate or absent insulin replacement, which occurs in people with type 1 diabetes and infrequently in those with type 2 diabetes. It typically occurs in newly diagnosed type 1 patients or in those who have experienced interrupted insulin replacement, and rarely in people with type 2 diabetes who have concurrent unusually stressful conditions such as sepsis or  pancreatitis or are on high-dose steroid therapy.

Signs and symp-toms include nausea, vomiting, abdominal pain, deep slow (Kussmaul) breathing, change in mental status, elevated blood and urinary ketones and glucose, an arterial blood pH lower than 7.3, and low bicarbonate (< 15 mmol/L).

The fundamental treatment for DKA includes aggressive intra-venous hydration and insulin therapy and maintenance of potas-sium and other electrolyte levels. Fluid and insulin therapy is based on the patient’s individual needs and requires frequent reevaluation and modification. Close attention has to be given to hydration and renal status, the sodium and potassium levels, and the rate of correction of plasma glucose and plasma osmolality. Fluid therapy generally begins with normal saline. Regular human insulin should be used for intravenous therapy with a usual start-ing dose of about 0.1 IU/kg/h.

B. Hyperosmolar Hyperglycemic Syndrome

Hyperosmolar hyperglycemic syndrome (HHS) is diagnosed in per-sons with type 2 diabetes and is characterized by profound hypergly-cemia and dehydration. It is associated with inadequate oral hydration, especially in elderly patients, with other illnesses, the use of medica-tion that elevates the blood sugar or causes dehydration, such as phenytoin, steroids, diuretics, and β blockers, and with peritoneal dialysis and hemodialysis. The diagnostic hallmarks are declining mental status and even seizures, a plasma glucose of over 600 mg/dL, and a calculated serum osmolality higher than 320 mmol/L. Persons with HHS are not acidotic unless DKA is also present.

The treatment of HHS centers around aggressive rehydration and restoration of glucose and electrolyte homeostasis; the rate of correction of these variables must be monitored closely. Low-dose insulin therapy may be required.