Sodium Serum Adult: 136-145 mEq/L Child: 138-145 mEq/L Infant: 139-146 mEq/L Newborn: 133-146 mEq/L Premature (48 hours): 128-148 mEq/L To monitor electrolyte balance, water balance, and acid-base balance Hypernatremia Dehydration Diabetic Ketoacidosis Cushing's Syndrome Azotemia Aldosteronism Excessive saline infusion Profuse sweating Inadequate thirst Vomiting or Diarrhea Hyponatremia Addison's Disease Diuretic therapy Hypopituitarism Salt-wasting nephritis Vomiting or Diarrhea Hypothyroidism Burns Glucocorticoids Acute water deficiency Syndrome of inappropriate antidiuretic hormone. Cirrhosis Nephrotic Syndrome Acute or chronic renal failure Congestive Heart Failure Central nervous system disturbance Ketonuria Bicarbonaturia Hemolysis