Hyperkalemia: treatment options

Abstract

Although extracellular potassium accounts for only 1% to 2% of total body potassium, its concentration, [K+], is critical because it affects the depolarization of electrically excitable tissues such as heart and skeletal muscle. Renal failure is a predisposing factor in three-quarters of cases of hyperkalemia. Drugs contribute to the development of hyperkalemia in half of the cases, and most cases are multifactorial. Because hyperkalemia can lead to fatal arrhythmias, it deserves respect as a genuine electrolyte emergency. Nonetheless, recent data highlight the poor correlation of the EKG with [K+]. When present, however, EKG changes should be rapidly antagonized by infusion of calcium salts. Additional measures include shifting potassium from the extracellular to the intracellular compartment, removing potassium from the body, and eliminating risk factors for recurrence. Insulin is the most reliable agent for promoting transcellular shift of potassium. Albuterol can be used alone or to augment the effect of insulin. Alkalinization with bicarbonate, although formerly recommended as a mainstay of therapy, is not efficacious. Hemodialysis rapidly and reliably removes potassium and lowers [K+]. Exchange resins are also useful in removing potassium. Precise data on the quantity of potassium removed with current hemodialysis techniques or with resin are lacking. Although effective, rapid, and convenient means of treating hyperkalemia are available, physicians frequently fail to use them effectively.