All issues > Volume 49(5); 2006

Review Article

Korean J Pediatr. 2006;49(5):463-469. Published online May 15, 2006.

Hypernatremia and hyponatremia

Dong Un DU Kim¹

¹Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Korea

Correspondence Dong Un DU Kim ,Email: dukim@catholic.ac.kr

Abstract

Sodium is the major cation of the extracellular fluid and the primary determinant of extracellular osmolality. Therefore, hypernatremia causes water movement out of cells, while hyponatremia causes water movement into cells, resulting in cellular shrinkage and cellular swelling, respectively. Serious central nervous system symptoms may complicate both conditions. Since hypernatremia and hyponatremia are accompanied by abnormalities in water balance, it is essential to understand the mechanisms regulating extracellular osmolality and volume as well as the pathophysiology of hypernatremia and hyponatremia, in order to manage both conditions with swiftness and safety.

Keywords :Hypernatremia , Hyponatremia , Osmolality , Volume , Water balance