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Hydration Assessment

Fluid Volume Deficit


Signs and Symptoms

Loss of water and electrolytes due to:

  • Fever
  • GI suction (e.g. low intermittent Gomco)
  • Vomiting and diarrhea
  • Diaphoresis (sweating)
  • Increased urine output (polyuria)

  • Dry mucous membranes
  • Decreased skin turgor
  • Urine output <1ml/kg/hr
  • Hypotension
  • Sunken eyes
  • Depressed fontanels
  • Non tearing
  • Dry, cracked tongue
  • High urine specific gravity

Insensible Fluid Losses

Influencing factors:

  • Suctioning
  • Diaphoresis
  • Fever
  • Hyperthermia
  • Increased activity
  • Hyperventilation
  • Radiant warmers
  • Phototherapy

Fluid Volume Excess


Signs and Symptoms

  • Renal/liver failure
  • Congestive Heart Failure (CHF)
  • Over administration of fluids
  • High sodium intake

  • Peripheral edema
  • Puffy eyes
  • Full/bulging fontanels
  • Wet chest
  • Pulmonary edema
  • Pleural effusions
  • Ascites (fluid accumulation within the abdominal cavity)
  • Distended neck veins
  • Bounding pulses
  • Decreased urinary output (Oliguria)

Special Considerations

In relation to fluids, infants:

  • Have proportionally more body water
  • Are quite vulnerable to fluid volume deficit
  • Have a high metabolic rate and large metabolic wastes to excrete daily
  • Need relatively larger water intake than older children
  • Have immature kidneys which are unable to concentrate urine efficiently
  • Experience greater fluid loss through the skin
  • Are prone to fluid/electrolyte imbalance

Special Fluid Requirements

In certain situations, as indicated below, patients' require more or less hydration than their standard daily fluid requirements.


Fluid restriction

  • chemotherapy
  • increased insensible losses
  • increased respiratory rate
  • fever
  • SIADH (Syndrome of Inappropriate Antidiuretic Hormone Secretion)
  • renal failure
  • cardiopulmonary failure   

Urinary Output in Paediatric Patients

  • Normal: 1 – 2ml/kg/hr
  • Oliguria: <1.0ml/kg/hr
  • Anuria: no urine output
  • Polyuria: > 3ml/kg/hr
  • Older children: 30 ml/hr is the minimum normal output