Objective: To study efficacy and safety of hypertonic saline administration in the management of hyponatremic seizures.
Design: Retrospective, observational, cross-sectional study with factorial design.
Setting: In-patient population in a university hospital.
Patients: All children admitted with serum sodium concentrations less than 125 mmol/L. Sixty-nine episodes of severe hyponatremia in 60 children were reviewed. Forty-one of these children presented with seizures.
Interventions: Twenty-five of 41 seizure patients received an iv bolus of 4 to 6 mL/kg body weight of 3% saline. Twenty-eight patients were treated with a benzodiazepine and/or phenobarbital with or without the subsequent administration of hypertonic saline.
Measurements and main results: Thirteen treatment failures and ten instances of apnea occurred among the 28 patients treated with benzodiazepine/phenobarbital. Administration of hypertonic saline resulted in resolution of seizures and apnea in all cases. Those patients receiving 3% saline had a higher serum sodium increase rate from 0 to 4 hrs than the remaining patients (3.1 +/- 1.3 vs. 1.7 +/- 1.2 mmol/L.hr, p less than .01). None developed subsequent neurologic deterioration or clinical manifestations of osmotic demyelination syndrome.
Conclusion: Treatment of hyponatremic seizures with routine anticonvulsants may be ineffective and is associated with a considerable incidence of apnea. A rapid increase in the serum sodium concentration by 3 to 5 mmol/L with the use of hypertonic saline is safe and efficacious in managing acute symptomatic hyponatremia.