A nurse is assigned a client who is diagnosed with syndrome of inappropriate antidiuretic hormone (SIADH) with a serum sodium level of 118 mEq/L. Which of the following interventions will the nurse anticipate for this client? (Select all that apply)

Choice A reason: Initiating 3% sodium chloride infusion is appropriate for severe hyponatremia (118 mEq/L) in SIADH, as hypertonic saline corrects low serum sodium by increasing extracellular sodium concentration. This addresses water retention from excess ADH, preventing neurological complications like seizures, making it a key intervention. Choice B reason: Administering tolvaptan, a vasopressin receptor antagonist, is effective in SIADH, as it promotes water excretion, increasing urine output and correcting hyponatremia. By blocking ADH action, it reduces fluid retention, making it a suitable intervention for severe cases with low sodium levels. Choice C reason: Administering lactulose is used for hepatic encephalopathy to reduce ammonia, not for SIADH’s hyponatremia. It does not address electrolyte imbalances caused by water retention, making it irrelevant for correcting sodium levels or managing SIADH’s pathophysiology. Choice D reason: Maintaining seizure precautions is critical in SIADH with severe hyponatremia (118 mEq/L), as low sodium disrupts neuronal membrane stability, increasing seizure risk. Precautions like padded rails and anticonvulsants protect the client, making this a necessary intervention for safety. Choice E reason: Administering a 3-liter 5% dextrose water bolus is contraindicated in SIADH, as it adds free water, worsening hyponatremia by further diluting serum sodium. Hypertonic saline or fluid restriction is needed, making this an inappropriate and potentially harmful intervention.