Department of Pediatrics, Children’s Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania. Michael L. Moritz, MD, is an associate professor of pediatrics at the University of Pittsburgh School of Medicine and the clinical director of pediatric nephrology and medical director of pediatric dialysis at the Children’s Hospital of Pittsburgh of UPMC. Dr Moritz is a leading expert in the epidemiology and treatment of disorders of sodium and water homeostasis in children.
Disorders in serum sodium, hyponatremia and hypernatremia, are frequently encountered in both inpatient and outpatient settings. Many sodium disorders are iatrogenic, caused by inappropriate intravenous fluid management. The methods of prevention and treatment of serum disorders differ based on the underlying disease states. Nine cases are presented to illustrate different aspects of fluid management, with an emphasis on the prevention and treatment of disorders in serum sodium. Key concepts that are discussed are (1) when to use an isotonic fluid versus a hypotonic fluid, (2) when to restrict or liberalize maintenance intravenous fluids, (3) how to use 3% sodium chloride for the treatment of hyponatremic encephalopathy, (4) when to use desmospressin to prevent the overcorrection of chronic hyponatremia, and (5) strategies to treat different causes of hypernatremic dehydration in children.