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Emergency Medicine/Dehydration

< Emergency Medicine

Dehydration means your body does not have as much water and fluids as it should. This can be caused by losing too much fluid, not drinking enough water or fluids, or both. Vomiting and diarrhea are common causes.

Infants and children are more susceptible to dehydration than adults because of their smaller body weights and higher turnover of water and electrolytes. The elderly and those with illnesses are also at higher risk.

Dehydration is classified as mild, moderate, or severe based on how much of the body's fluid is lost or not replenished. When severe, dehydration is a life-threatening emergency.


  • Dry or sticky mouth.
  • Low or no urine output; concentrated urine appears dark yellow.
  • Not producing tears.
  • Sunken eyes.
  • Markedly sunken fontanelles (the soft spot on the top of the head) in an infant.
  • Lethargic or comatose (with severe dehydration).
  • In addition to the symptoms of actual dehydration, you may also have:
    • vomiting
    • diarrhea
    • the feeling that you "can't keep anything down"


  • Drinking fluids is usually sufficient for mild dehydration. It is better to have frequent, small amounts of fluid (using a teaspoon or syringe for an infant or child) rather than trying to force large amounts of fluid at one time. Drinking too much fluid at once can bring on more vomiting.
  • Electrolyte solutions or freezer pops are especially effective. These are available at pharmacies. Sport drinks contain a lot of sugar and can cause or worsen diarrhea. In infants and children, avoid using water as the primary replacement fluid.
  • Intravenous fluids and hospitalization may be necessary for moderate to severe dehydration. The doctor will try to identify and then treat the cause of the dehydration.

Treatment includes starting NS@20ml/kg slow push until signs of severe dehydration disappear. Avoid Ringer Lactate till patient passes urine. Maintenance fluid depends on body weight. Either DNS or RL may be used 10 kg and less 100ml/Kg 10–20 kg 1000mL+50ml/kg 20+ Kg 1500ml+ 20 ml/kg It may be advisable to give half the calculated fluid in the first 8 hours and the remaining over the next 16 hours

  • Precautions

check for pulmonary oedema replenish Potassium as required Chills may occur due to fluid administration rule out infectious causes

  • Most cases of stomach viruses (also called viral gastroenteritis) tend to resolve on their own after a few days.