Electrolyte Disorders

Electrolyte disorders are common in the ICU. Severe hyperkalemia is a life-threatening disorder, requiring immediate therapy. This chapter provides information on the prevention, prognosis, diagnosis, management, and treatment of electrolyte disorders, namely hyperkalemia, hypokalemia, hyperphosphatemia, hypophosphatemia, hyponatremia, hypernatremia, hypercalcemia, and hypocalcemia. The prevalence of hyperkalemia in hospitalized patients has been reported to be between 1% and 10%. Physical examination is often unremarkable in patients with hyperkalemia but in severe cases can reveal ascending muscle weakness or an irregular heart rhythm. All changes will reverse with treatment of the hyperkalemia. Treatment of chronic hyperphosphatemia most often occurs in patients with renal dysfunction and revolves around dietary phosphate restriction (<900 mg/day) and phosphate binder therapy to decrease intestinal absorption.