Pediatric Dehydration

Globally, dehydration is a leading cause of pediatric morbidity and mortality. Diarrheal disease and dehydration cause 14% to 30% of deaths among infants and toddlers worldwide. Viruses cause most cases of gastroenteritis in both developed and low-to-middle-income countries, and rotavirus is the most frequent etiology of gastroenteritis globally. In the United States, however, rotavirus hospitalizations have decreased since the licensing of the oral rotavirus vaccine in 2006, and now norovirus and other enteroviruses cause more gastroenteritis than rotavirus.

The World Health Organization (WHO) defines dehydration as a condition caused by excessive loss of body water. Infants and children have a higher percentage of total body water (TBW) than adults, approximately 65% to 80%. Young children are especially susceptible to dehydration because they cannot independently communicate their thirst to caregivers or access fluids. Infants have a relatively greater fluid requirement due to increased insensible fluid losses from their higher body surface area. Dehydration is classified into 3 categories depending on the value of the serum sodium: isotonic, hypotonic, and hypertonic. The etiologies and recommended treatments are different for each group, with the common goal of restoring water and electrolyte deficits, providing maintenance fluids, and replacing losses.