Acute life-threatening arrhythmias caused by severe hyperkalemia after induction of anesthesia in an infant with methylmalonic acidemia

Methylmalonic acidemia (MMA) is a very rare genetic disease of metabolism that progressively leads to neurological and renal sequelae. This report describes an unusual case of a patient with MMA who developed severe hyperkalemia and severe dysrhythmia during anesthesia. A 13-month-old male infant with MMA underwent urgent insertion of a port-a-cath under general anesthesia. A life-threatening arrhythmia suddenly occurred, with severe hyperkalemia (up to 7.4 mmol/L), immediately following induction of anesthesia. Emergent resuscitation was successfully carried out, with a complete neurological recovery after 7 days after surgery. Although MMA is a rare complication, the possibility of severe hyperkalemia should be considered in the differential diagnosis of patients with MMA presenting with wide QRS complex tachycardia. The management and intraoperative complications of this disorder are reported here, and the available literature is reviewed.