Extra Corporeal Life Support in life-threatening digoxin overdose: A bridge to antidote

Abstract

Digoxin poisoning is a potentially life-threatening overdose that may result in refractory atrioventricular block and ventricular arrhythmias. The efficacy of digoxin-specific Fab fragments in controlling all manifestations of digoxin toxicity was consistently evidenced. However, specific Fab fragments are very expensive meanwhile digoxin poisoning is very rare. The likelihood of occurrence of a severe digoxin overdose in a setting where specific Fab fragments are not available is very high. Single case report. The extracorporeal support was provided by the centrifugal pump. An equimolar dose of digoxin-specific Fab fragment was administered according to the dosage regimen reported by Schaumann et al who resulted in the greatest amount of Fab eliminated in the urine bound to digoxin [1] . We report a case of poisoning with 22.5 mg of digoxin in a previously healthy 50-year-old male who experienced the onset of an atrioventricular block followed by a refractory electromechanical dissociation. The installation of an arteriovenous extracorporeal support prevented further development of a multi-organ failure in this patient in refractory cardiac arrest while allowing for the supply of Fab fragments, as well as the infusion of that expensive antidote over a period of time, resulting in the optimization of the Fab fragments’ binding capacity. The patient recovered completely and gave his written informed consent for publication of the case. This case report along with another one [2] support the addition of life-threatening digoxin poisonings as a possible cause of refractory electromechanical dissociation. Digoxin-specific Fab fragments should be considered as first-line treatment. However, in case of sudden hemodynamic compromise, while Fab fragments are not immediately available, ECLS might be life-saving, enabling a “bridge to antidote” along with the infusion of digoxin-specific Fab fragments using the most efficient dosage regimen. Life-threatening digoxin poisonings may result in a sudden onset of refractory electromechanical dissociation, a rhythm disturbance that ought to be included in the list of digoxin overdose-induced dysrhythmias. The analysis of prognostic factors at the time of presentation may help to focus on severe poisonings. When faced with a life-threatening digoxin overdose, the attending physician should consider the availability of not only Fab, but also ECLS. Fab fragments are the first-line treatment. However, in case of sudden hemodynamic compromise when Fab fragments are not immediately available, ECLS might be life-saving enabling a “bridge to specific treatment” along with the infusion of Fab fragments using the most efficient dosage regimen. Conversely, Fab administration might result in decreasing the duration of ECLS implementation.