Hyponatremia, a Concise Practical Review

Hyponatremia, defined as serum sodium below 135mmol / L, is the most common electrolyte abnormality. Its causes can be divided into hypovolemic, euvolemic and hypervolemic according to volume status, and to hypoosmolar, pseudohyponatremia and hyperosmolar according to plasma osmolality. Hyponatremia can be life-threatening if acute or severe. Similarly, inappropriate treatment can lead to significant morbidities. Frequent monitoring and timely interventions are essential to prevent complications. Hyponatremia symptoms and duration dictate the treatment pace. Hyponatremia with moderate to severe CNS symptoms requires immediate treatment with hypertonic intravenous fluid. The aggressive treatment of chronic hyponatremia, however, increases the risk of osmotic demyelination syndrome. Water restriction and treatment of the underlying cause are the primary management of hyponatremia in edematous patients or are caused by syndrome-inappropriate antidiuresis.