How is oral rehydration therapy (ORT) administered for the treatment of dehydration?

Updated: Dec 07, 2018
  • Author: Lennox H Huang, MD, FAAP; Chief Editor: Timothy E Corden, MD  more...
  • Print

Mild or moderate dehydration can usually be treated very effectively with ORT. [19]

Vomiting is generally not a contraindication to ORT. If evidence of bowel obstruction, ileus, or acute abdomen is noted, then intravenous rehydration is indicated.

Calculate the fluid deficit. Physical findings consistent with mild dehydration suggest a fluid deficit of 5% of body weight in infants and 3% in children. Moderate dehydration occurs with a fluid deficit of 5-10% in infants and 3-6% in children (see Table 1 and Table 2). The fluid deficit should be replaced over 4 hours. Documented recent change in weight remains the standard for calculating fluid deficit if the values are available. (This is especially helpful with infants since they have relatively frequent well childcare visits that include weight checks.)

The oral rehydration solution should be administered in small volumes very frequently to minimize gastric distention and reflex vomiting. Generally, 5 mL of oral rehydration solution every minute is well tolerated. Hourly intake and output should be recorded by the caregiver. As the child becomes rehydrated, vomiting often decreases and larger fluid volumes may be used.

If vomiting persists, infusion of oral rehydration solution via a nasogastric tube may be temporarily used to achieve rehydration. Intravenous fluid administration (20-30 mL/kg of isotonic sodium chloride 0.9% solution over 1-2 h) may also be used until oral rehydration is tolerated. According to a Cochrane systematic review, for every 25 children treated with ORT for dehydration, one fails and requires intravenous therapy. [20]

Replace ongoing losses from stools and emesis (estimate volume and replace) in addition to replacing the calculated fluid deficit.

An age appropriate diet may be started as soon as the child is able to tolerate oral intake.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!