1. Serum electrolytes. Serum sodium concentration > 146 mEq/L is abnormal. Monitor serum electrolytes for hypokalemia and hypercalcemia, which are possible etiologies of hypernatrem-ia. Look for hypocalcemia as a sequela of hypernatremia. Follow serum sodium concentration closely.
2. Renal studies. Elevated BUN and creatinine may suggest intrinsic renal disease. If the BUN-to-creatinine ratio is > 20:1, dehydration is present; when the ratio is < 10:1, intrinsic renal disease is present.
3. Serum glucose. Mild hyperglycemia is often noted in hypernatremia. Etiology of elevated serum glucose is unknown.
4. Urine osmolality. Value > 700 mOsm/kg-H2O suggests that child's renal concentrating capacity is intact, eliminating diabetes insipidus as a cause of hypernatremia.
5. Spot urine sodium. In the presence of hypernatremia, spot urine sodium < 10 mEq/L suggests extrarenal losses of sodium.
6. Water deprivation test. Performed in stable, well-hydrated patients. Serum sodium concentration and osmolality, urine specific gravity and osmolality, and weight are monitored every 2 hours. Patient is water deprived until one of the following occurs: loss of more than 3% of body weight; or serum sodium concentration > 150 mEq/L and serum osmolality > 300 mOsm/kg-H2O. Patients with central or nephrogenic diabetes insipidus develop serum sodium concentrations > 150 mEq/L in the face of urine osmolality < 150 mOsm/kg-H2O and weight loss of 3% or more. Patients with central diabetes insipidus respond to DDAVP or vasopressin by increasing their urine osmolality and decreasing urine volume.
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Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...