Dehydration

This page is for adult patients. For pediatric patients, see: dehydration (peds)

Background

  • Decreased total body water resulting in relative hypertonicity and hypernatremia
  • Usually resulting from inadequate fluid intake or increased free water loss
  • Often confused with hypovolemia in which total body water is lost with a relative hypotonic or isotonic state

Clinical Features

Differential Diagnosis

Causes of sinus tachycardia

Evaluation

  • Urine sodium concentration
  • FENa (fractional excretion of sodium)
  • Urine osmolality
  • Urinalysis

Management

Disposition

See Also

Calculators

Maintenance Fluids (4-2-1 Rule)

Maintenance IV Fluids (4-2-1 Rule)
Parameter Value
Patient Weight (kg)
Maintenance Rate
Hourly Rate mL/hr
Daily Volume mL/day
References
  • Holliday MA, Segar WE. The maintenance need for water in parenteral fluid therapy. Pediatrics. 1957;19(5):823-832. PMID 13431307.
  • 4-2-1 Rule: 4 mL/kg/hr for first 10 kg + 2 mL/kg/hr for next 10 kg + 1 mL/kg/hr for each kg above 20 kg.

External Links

References