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Clinical assessment and diagnosis of hypovolemia (dehydration) in children

Michael J Somers, MD
Section Editor
Tej K Mattoo, MD, DCH, FRCP
Deputy Editor
Melanie S Kim, MD


Fluid therapy is intended to maintain the normal volume and composition of body fluids and, if needed, to correct any existing abnormalities. In children, the most common abnormality is hypovolemia.

Volume depletion occurs when fluid is lost from the extracellular space at a rate that exceeds intake. The most common sites for extracellular fluid loss are:

  • Gastrointestinal tract (eg, diarrhea, vomiting, bleeding)
  • Skin (eg, fever, burns)
  • Urine (eg, glucosuria, diuretic therapy, diabetes insipidus)

In addition, hypovolemia can result from prolonged inadequate intake without excessive losses.

Children are at increased risk for hypovolemia for the following reasons:


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Literature review current through: Feb 2015. | This topic last updated: Feb 13, 2015.
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