For SIADH with seizures due to severe hyponatremia, which acute treatment is recommended?

For SIADH with seizures due to severe hyponatremia, which acute treatment is recommended?

• A. 3% saline for seizures
• B. Fluid restriction only
• C. High-dose dopamine agonists
• D. Urinary catheterization

Answer: (A)

When SIADH causes severe hyponatremia with seizures, the priority is to reverse brain swelling quickly. Hypertonic saline, specifically 3% NaCl, is the treatment of choice because its high sodium concentration rapidly increases serum osmolality, drawing water out of swollen brain cells and stopping the seizure by reducing cerebral edema. The usual approach is small, controlled boluses (for example, 100 mL of 3% saline over 10 minutes) with frequent reassessment of neurologic status and serum sodium, repeating as needed while watching to prevent overcorrection. Monitor sodium levels every few hours and avoid a too-rapid rise, which risks osmotic demyelination. Fluid restriction is used for chronic management of SIADH but does not address an acute seizure. Dopamine agonists and urinary catheterization do not treat the hyponatremia or its neurologic consequences.

When SIADH causes severe hyponatremia with seizures, the priority is to reverse brain swelling quickly. Hypertonic saline, specifically 3% NaCl, is the treatment of choice because its high sodium concentration rapidly increases serum osmolality, drawing water out of swollen brain cells and stopping the seizure by reducing cerebral edema. The usual approach is small, controlled boluses (for example, 100 mL of 3% saline over 10 minutes) with frequent reassessment of neurologic status and serum sodium, repeating as needed while watching to prevent overcorrection. Monitor sodium levels every few hours and avoid a too-rapid rise, which risks osmotic demyelination.

Fluid restriction is used for chronic management of SIADH but does not address an acute seizure. Dopamine agonists and urinary catheterization do not treat the hyponatremia or its neurologic consequences.