How is oral rehydration salt (ORS) given to kids to treat dehydration caused by diarrhea?

Oral Rehydration Salt Administration for Children with Diarrhea

Oral rehydration salt (ORS) should be administered based on the child's degree of dehydration, with 50 mL/kg over 2-4 hours for mild dehydration (3-5%) and 100 mL/kg over 2-4 hours for moderate dehydration (6-9%), while severe dehydration requires immediate IV rehydration followed by ORS. 1

Assessment of Dehydration

Before administering ORS, assess the child's dehydration level:

• Mild dehydration (3-5%):

  • Minimal electrolyte disturbances
  • Thirst
  • Slightly dry mucous membranes

• Moderate dehydration (6-9%):

  • Higher risk of electrolyte abnormalities
  • Decreased skin turgor
  • Dry skin

• Severe dehydration (≥10%):

  • Severe electrolyte disturbances
  • Lethargy
  • Prolonged skin retraction
  • Cold extremities

ORS Administration Protocol

For Mild Dehydration (3-5%):

• Administer 50 mL/kg ORS over 2-4 hours 1
• Start with small volumes (e.g., 1 teaspoon) and gradually increase 2
• Reassess hydration status after 2-4 hours

For Moderate Dehydration (6-9%):

• Administer 100 mL/kg ORS over 2-4 hours 1
• Use the same administration technique as for mild dehydration
• Reassess after 2-4 hours

For Severe Dehydration (≥10%):

• Begin with IV rehydration (20 mL/kg boluses of Ringer's lactate or normal saline) 1
• When mental status improves, transition to oral rehydration
• Continue to monitor closely

For Ongoing Losses:

• Replace each watery stool with 10 mL/kg ORS 2, 1
• Replace each episode of vomiting with 2 mL/kg ORS 2, 1

Managing Vomiting

For children with vomiting:

• Administer small, frequent volumes (e.g., 5 mL every minute) 2
• Use a spoon or syringe with close supervision
• Gradually increase the amount as tolerated
• Note that correcting dehydration often reduces vomiting frequency 2

Nutritional Management During ORS Administration

• Breastfed infants: Continue nursing on demand throughout illness 2, 1
• Formula-fed infants: Resume full-strength formula immediately after initial rehydration 1
• Older children: Resume regular diet with emphasis on starches, cereals, yogurt, fruits, and vegetables 1
• Avoid: Foods high in simple sugars and fats 1

Composition of ORS

The WHO-recommended reduced osmolarity ORS contains:

• Sodium: 65-70 mEq/L
• Glucose: 75-90 mmol/L
• Potassium: 20 mEq/L 1, 3

This formula has been shown to decrease diarrhea volume and reduce the need for IV fluids compared to older formulations 3.

Home Management

• Parents should be instructed to:

  • Begin ORS at the first sign of diarrhea
  • Replace ongoing losses as described above
  • Continue appropriate feeding
  • Monitor for warning signs requiring medical attention 2

• Warning signs include:

  • Irritability or lethargy
  • Decreased urine output
  • Intractable vomiting
  • Persistent diarrhea 1

Common Pitfalls to Avoid

• Inappropriate fluid replacement: Using hypotonic fluids (water, tea) without adequate sodium can worsen hyponatremia 1
• Delaying feeding: There is no justification for "resting the bowel" - feeding should resume as soon as possible 2
• Antidiarrheal agents: These are contraindicated in children as they can cause serious side effects 1
• Inadequate volume: Children who tolerate less than 15 mL/kg of ORS during initial rehydration are more likely to fail oral rehydration therapy 4

Effectiveness of ORS

Studies have shown that ORS is as effective as IV therapy for treating mild to moderate dehydration in children, with success rates of approximately 80% when properly administered 4. The low-osmolality ORS currently recommended by WHO has been shown to be more effective than previous formulations, with reduced need for IV therapy 3.