Hypernatremia--problems in management.

Hypernatremia may be produced under several different circumstances but most frequently is the result of excessive water loss with diarrhea and the excessive solute load secondary to inappropriate preparation of formula. The clinical manifestations vary and depend primarily on the degree of dehydration and the rate at which the hyperosmolar state has been reached. The management of the patient will, of course, depend upon the mechanism of hypernatremia and degree of dehydration and/or hypovolemia that is present. It seems clear that the exact nature of the rehydrating solution is not of major importance. The volume is of great concern but most vital seems to be the rate of rehydration. If rehydration is accomplished too rapidly the child becomes edematous, develops increased intracranial pressure, stupor, and convulsions. If fluids are given slowly and at a well regulated rate, these complications can usually be avoided. The patient should be monitored regularly with electrolytes, careful determination of weights, and records of intake and output. The rate of rehydration should be monitored to assure that the planned schedule of 24 to 72 hours (depending on the severity of the problem) is followed. Approximately 10 to 15 per cent of children with serum sodium of 160 mEq per liter or greater will have permanent neurological deficits.