Under Recognized Toxicity of Flecainide Overdose

Flecainide is an antiarrhythmic with several adverse effects, including dysrhythmias and hemodynamic collapse with an overdose fatality rate of 22.5% (1-3). Here we present a case of intentional flecainide ingestion leading to critical illness. Emergency medical services (EMS) was dispatched to a 17-year-old female after a witnessed flecainide ingestion. Arrival vitals were pulse 120, blood pressure 96/60, and Glasgow Coma Score 15. No initial electrocardiogram was performed. On arrival at the hospital, the patient quickly developed a seizure followed by cardiac arrest. Cardiopulmonary resuscitation was performed with return of spontaneous circulation (ROSC); ECG demonstrated a wide-complex tachycardia. Intubation was performed and norepinephrine started. The patient was also given sodium bicarbonate, lorazepam, levetiracetam, lidocaine, amiodarone, and lipid emulsion. The patient transferred to a pediatric center, where she developed pulseless ventricular tachycardia. After defibrillation and administration of calcium chloride and lipid emulsion, ROSC was achieved. Worsening hypotension and recurrent ventricular tachydysrhythmias led to the pursuit of extracorporeal membrane oxygenation (ECMO). Extracorporeal membrane oxygenation continued through day 5, and the patient was discharged on day 13. This case of an intentional flecainide overdose resulting in critical illness highlights several aspects of prehospital care. Clinician knowledge of the nature of illness, agent ingested, and magnitude of ingestion is critical to timely care. When patients decompensate, lack of access to this information can delay administration of decontamination agents, specific antidotes, and toxicology expert consultation. In this case, a prehospital electrocardiogram was not obtained. Given the rapid development of unstable tachydysrhythmias, having this information en route and on arrival at the emergency department may have expedited management. In all toxic ingestions, early electrocardiograms are paramount. Lastly, the patient may have benefited from direct transport to a pediatric center given it would have added only a few minutes' delay and the EMS crew was advanced life support-capable. In general, one cannot know whether a longer transfer time will result in critical decompensation. Nonetheless, one might consider certain presentations with capacity for critical illness requiring highly specialized care as an indication for direct transport.