Intravenous lipid emulsion therapy for flecainide toxicity

摘要

Intravenous lipid emulsion (ILE) is an accepted antidote for systemic local anesthetic toxicity and may be useful for other lipophilic drugs with cardiac toxicity. Flecainide is a class IC antiarrhythmic drug related to lidocaine. Flecainide is highly lipophilic with an octanol/water partition coefficient of 3.8 (similar to that of bupivacaine). In overdose, flecainide produces wide complex dysrhythmias and cardiogenic shock. We describe two patients with life-threatening flecainide overdoses which were refractory to standard treatment and which responded rapidly to ILE. Patient 1 was a 49-year-old man who had bradycardia (31 bpm) and hypotension (50?mmHg systolic) after taking 2400?mg of flecainide. His ECG showed a wide complex bradycardia (QRS 178 ms). Bradycardia and hypotension persisted despite atropine, glucagon, CPR, endotracheal intubation, epinephrine, dopamine, magnesium sulfate, and sodium bicarbonate. Patient 2 was a 69-year-old man who ingested 1?g of flecainide, 12?mg of clonazepam, and 1?mg of ropinirole. His ECG showed a rate of 76?bpm with QRS of 268?ms. His blood pressure fell to 66/29?mmHg. Both patients rapidly improved with ILE bolus and infusion. ILE appears useful in severe flecainide toxicity with cardiogenic shock that fails to respond to conventional therapy.