Diabetic ketoacidosis

Diabetic ketoacidosis is a life-threatening condition requiring immediate hospitalization and treatment. Pathogenesis is an absolute or relative insulin deficiency in the presence of elevated catabolic hormone levels. Patients are dehydrated with Kussmaul respiration and a characteristic smell of acetone on the breath. Hyperglycaemia is accompanied by a metabolic acidosis due to excessive circulating ketone bodies. The aims of treatment are to rehydrate and give insulin. Potassium supplementation is invariably necessary and careful monitoring is necessary. With a satisfactory response to treatment in glucose and the acidosis infusion fluid is changed and insulin dose is halved as glucose falls below 15 mmol/L. When acidosis persists it is probably best to maintain the same dose of insulin and prevent hypoglycaemia with 10% glucose infusion. Complications occur including vomiting with aspiration, thrombotic events, and cerebral oedema. Marked hyperglycaemia is not accompanied by acidosis. Treatment is identical to that for ketoacidosis. Lactic acidosis in a diabetic is likely to be due to hypoxia although occasional cases are seen with metformin use in a patient with impaired renal function. It may be necessary to give large amounts of bicarbonate. Mortality rates are high.