Authors: Assadi F
Abstract
Hyponatremia, defined as a serum sodium concentration of <135 mmol/L, often develops as a consequence of elevated levels of arginine vasopressin (AVP) hormone. AVP elevation can occur in a number of common clinical conditions, including syndrome of inappropriate secretion of AVP, volume depletion, postoperative states, heart failure, cirrhosis, neuroendocrine disorders and trauma. A history of concurrent illness and medication use, assessment of extracellular fluid volume as well as measurement of serum and urine osmolality and urine sodium concentration will help to establish the primary underlying causes. Presence or absence of significant neurologic signs and symptoms must guide treatment. Symptomatic hyponatremia must be treated promptly with 3% hy...