Clinical assessment and diagnosis of hypovolemia (dehydration) in children
- Michael J Somers, MD
Michael J Somers, MD
- Associate Professor of Pediatrics
- Harvard Medical School
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:
- Mange K, Matsuura D, Cizman B, et al. Language guiding therapy: the case of dehydration versus volume depletion. Ann Intern Med 1997; 127:848.
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- Rose BD. New approach to disturbances in the plasma sodium concentration. Am J Med 1986; 81:1033.
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- VOLUME DEPLETION VERSUS DEHYDRATION
- CLINICAL ASSESSMENT
- Degree of dehydration
- Type of fluid lost
- LABORATORY TESTING
- Serum sodium
- - Secretion of ADH
- - Prior fluid replacement
- Serum potassium
- Serum bicarbonate
- Urine sodium
- Urine osmolality and specific gravity
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS