Hyponatremia and Hypernatremia

• Hyponatremia and hypernatremia are usually caused by abnormal water balance. • Neurologic symptoms of hyponatremia and hypernatremia are caused by changes in effective plasma osmolality. • Assessment of volume status is key in evaluation of both hyponatremia and hypernatremia. • Overly rapid correction of chronic hyponatremia and hypernatremia can cause central pontine myelinolysis and cerebral edema, respectively. • Prediction equations should only be a rough guide for estimating the fluid administration rates. Frequent plasma sodium monitoring is essential in order to prevent overcorrection.