Cerebral edema in diabetic ketoacidosis.

Cerebral edema is the most important complication of diabetic ketoacidosis in children. It has a high mortality rate of 20 to 90% in different series. Twenty to 40% of survivors suffer from neurologic sequelae. The pathogenetic mechanisms are still controversial and the risk factors which are thought to predict its occurrence do not consistently correlate with cerebral edema in various studies. Prevention and recognition of early warning signs, such as decreased arousal, lethargy after initial improvement, headache, vomiting, relative bradycardia and relative hypertension, are crucial. Therapeutic guidelines to prevent cerebral edema in diabetic ketoacidosis include slow rehydration over about 48 hours, avoidance of hypotonicity and of unnecessary alkali therapy. Early recognition of cerebral edema and prompt institution of hypertonic therapy with mannitol may prevent permanent neurological sequelae.