Intravenous Sotalol for the Treatment of Ventricular Dysrhythmias in an Infant on Extracorporeal Membrane Oxygenation

Sotalol is a class III anti-arrhythmic agent with beta receptor blocking properties. Intravenous (IV) sotalol may be useful to treat refractory atrial and ventricular arrhythmias. A report on the efficacy and safety of IV sotalol in an infant on extracorporeal membrane oxygenation (ECMO) and continuous renal replacement therapy (CRRT), who developed refractory ventricular arrhythmias following surgery for congenital heart disease. A 10-day old infant with severe pulmonary valve stenosis underwent surgical pulmonary valvectomy and enlargement of the main pulmonary artery. Post-operatively, the patient developed hemodynamically significant accelerated idioventricular rhythm which was not responsive to a combination of amiodarone, lidocaine, and procainamide leading to 2 cardiac arrest events and placement on ECMO. The amiodarone infusion was uptitrated to 20 mcg/kg/min, but episodes of the hemodynamically compromising arrhythmia continued. Amiodarone was discontinued and IV sotalol was initiated at 42 mg/m²/day, divided to 3 doses, and administered every 8 h, which completely suppressed the arrhythmia. The initial sotalol dose was calculated based on a daily dose of 90 mg/m² and reduced by an age-related factor as recommended by the FDA approved prescribing information. Subsequently, acute kidney injury requiring CRRT developed. The patient remained on IV sotalol for 3 weeks and then transitioned to oral sotalol. The oral dose was increased to 44 mg/m²/day (3.5 mg every 8 h) to account for the difference in bioavailability between the IV and oral formulations. Serial sotalol levels during IV and PO therapy remained therapeutic on ECMO and CRRT. The patient maintained normal sinus rhythm on sotalol without adverse events. IV sotalol in the setting of ECMO and CRRT was safe and effective in controlling refractory hemodynamically compromising accelerated idioventricular rhythm unresponsive to amiodarone.