Fab Fragments of Digoxin-Specific Antibodies Used to Reverse Ventricular Fibrillation Induced by Digoxin Ingestion in a Child

Abstract

Digitalis poisoning is a rare problem in children, but it may be life threatening. A case of massive overdose of digoxin in a 2½-year-old boy that produced prolonged ventricular fibrillation refractory to conventional therapy is reported. After two hours the boy was given digoxin-specific Fab fragments of antibody in sufficient quantity to bind his estimated dose of 10 mg. By completion of the treatment minutes later, normal rhythm and circulation were restored. The serum free digoxin level before antibody administration was > 100 ng/ml, and it rapidly fell to undetectable levels after antibody was given. Digoxin bound to the antibody had a clearance half-life of approximately 48 hours. The child had no apparent neurologic damage and his intellectual function was normal on discharge. He had a transient hematuria and a residual incomplete right bundle branch block. Administration of purified Fab fragments of digoxin-specific antibodies can be life saving in children with digitalis poisoning, and prolonged cardiopulmonary resuscitation in children is justified when the cause of cardiac arrest is potentially reversible.