Answer: a. Initiate an infusion of 3% NaCl
c. Restrict fluids to 800 mL over 24 hours
e. Administer a vasopressin antagonist as prescribed
Explanation: Clients with SIADH experience excess secretion of antidiuretic hormone (ADH), which leads to excess intravascular volume, a declining serum osmolality, and dilutional hyponatremia. Management is directed at correcting hyponatremia and preventing cerebral edema. Hypertonic saline is prescribed when the hyponatremia is severe. Fluid restriction is a useful strategy aimed at correcting dilutional hyponatremia. Vasopressin antagonists are used to treat SIADH (furosemide is only safe to use if the serum sodium is at least 125 mEq/L).