Sudden cardiac death in a dialysis patient: hyperkalemia reconsidered

To many physicians, hyperkalemia is the first diagnosis ascribed to any patient with end-stage renal disease and abnormal electrocardiographic morphologies or dysrhythmias.

A 52-year-old man with end-stage renal disease presented in cardiac arrest. The patient was initially presumed to have hyperkalemia, based on the appearance of wide QRS complexes on the monitor. The diagnosis of hyperkalemia was incorrect; the patient was severely hypokalemic and suffered recurrent episodes of ventricular fibrillation and torsades de pointes.

An emergency physician's differential diagnosis of sudden cardiac arrest in the patient with end-stage renal disease should not be limited to hyperkalemia and myocardial infarction. Hypokalemia should also be considered. Hypokalemia may be an under-recognized cause of sudden cardiac death in this patient population.