Hyponatremia in the intensive care unit.

Hyponatremia is a common electrolyte disturbance encountered in the intensive care unit setting. The underlying etiology is multifactorial and includes processes that lead to both a baroreceptor-mediated and a baroreceptor independent increase in antidiuretic hormone release. Patients with hyponatremia have an increased mortality rate and therefore an understanding of the cause and treatment of this disorder is of paramount importance.