The history taking should include questions about the environment
in which symptoms developed, symptoms of the illness, and prior
treatment. Quantify the child’s intake and output. Ask
about intake—the amount, frequency, and types of fluids
taken (including orally, via gastrostomy tube, or parenterally).
For breastfed infants, ask if the infant is feeding or merely sucking.
For bottle-fed infants, ask how formula is prepared (e.g., premixed
or powdered formula) and whether other types of liquids have been
substituted, such as water, tea, or juices, because consumption
of the latter fluids can lead to electrolyte abnormalities. Assess
potential fluid losses by asking about vomiting and diarrhea (including
frequency, volume, and composition) and amount of urine output.
Other information needed to assess potential dehydration includes
amount of tear production, occurrence of drooling, and presence
or absence of sweating. Ask about level of activity and mental status,
skin color (pallor, cyanosis, mottling), and temperature, and, in infants,
whether parents or other caretakers have noticed a sunken fontanelle.
Signs, symptoms, and other information that may suggest causes for
dehydration include fever, respiratory symptoms, difficulty swallowing,
changes in appetite and thirst, medication use, possible toxic ingestion,
contacts with ill individuals, and travel history. Weight loss,
if accurately known, is the most reliable way to quantify the degree
of dehydration. Give special consideration to hydration status in
any child with an underlying disease for which fluid requirements
and losses are unique, such as diabetes, cystic fibrosis, thyroid
disease, neurologic diseases, tumor, pituitary dysfunction, diabetes
insipidus, adrenal diseases affecting mineralocorticoid production,
metabolic diseases, chronic GI illnesses, heart disease, burns,