What is the treatment for pediatric acute gastroenteritis?

Treatment of Pediatric Acute Gastroenteritis

Oral rehydration therapy with low-osmolarity oral rehydration solution (ORS) is the first-line treatment for mild to moderate dehydration in children with acute gastroenteritis, combined with immediate resumption of age-appropriate feeding without dietary restrictions. 1, 2

Initial Assessment of Dehydration Severity

Evaluate dehydration clinically by examining mental status, skin turgor, mucous membranes, capillary refill, and perfusion status, then categorize as: 1, 2

• Mild dehydration: 3-5% fluid deficit
• Moderate dehydration: 6-9% fluid deficit
• Severe dehydration: ≥10% fluid deficit with signs of shock or altered mental status

Weigh the child immediately to establish baseline for monitoring treatment effectiveness. 1, 3

Rehydration Protocol Based on Severity

Mild Dehydration (3-5% deficit)

• Administer 50 mL/kg of low-osmolarity ORS over 2-4 hours 1, 2
• Start with small volumes (5-10 mL every 1-2 minutes) using a teaspoon, syringe, or medicine dropper, then gradually increase as tolerated 1, 2
• Reassess hydration status after 2-4 hours; if still dehydrated, reestimate deficit and restart rehydration 1

Moderate Dehydration (6-9% deficit)

• Administer 100 mL/kg of low-osmolarity ORS over 2-4 hours using the same small-volume technique 1, 2
• If the child cannot tolerate oral intake or refuses to drink, consider nasogastric administration of ORS as an alternative to intravenous therapy 1, 4

Severe Dehydration (≥10% deficit, shock, altered mental status)

• This is a medical emergency requiring immediate intravenous rehydration 1, 3
• Administer 20 mL/kg boluses of isotonic crystalloid (lactated Ringer's or normal saline) until pulse, perfusion, and mental status normalize 1, 3
• May require two IV lines or alternate access sites (venous cutdown, femoral vein, intraosseous infusion) 1
• Once mental status normalizes, transition to oral ORS to complete the remaining fluid deficit 1, 3

Important caveat: Malnourished infants may benefit from smaller-volume, frequent boluses of 10 mL/kg due to reduced cardiac capacity with larger volume resuscitation. 1

Replacement of Ongoing Losses During Both Phases

Replace ongoing fluid losses continuously throughout rehydration and maintenance: 1, 3

• Children <10 kg: 60-120 mL ORS per diarrheal stool or vomiting episode (up to ~500 mL/day) 1, 2
• Children >10 kg: 120-240 mL ORS per episode (up to ~1 L/day) 1, 2
• Alternatively, if losses can be measured accurately: 1 mL ORS per gram of diarrheal stool, or 10 mL/kg per watery stool and 2 mL/kg per vomiting episode 1, 3

Nutritional Management

Resume age-appropriate normal diet immediately upon or during rehydration—do not restrict diet or use "clear liquids only" approach. 1, 2

• Breastfed infants: Continue nursing on demand throughout the entire illness without interruption 1, 3
• Bottle-fed infants: Resume full-strength formula immediately upon rehydration; lactose-containing formulas are tolerated in most instances 1, 3
• Older children: Offer age-appropriate diet every 3-4 hours including starches, cereals, yogurt, fruits, and vegetables 1, 3

Adjunctive Therapies

Antiemetics

• Ondansetron may be given to children >4 years of age to facilitate oral rehydration when vomiting is present, but only after adequate hydration is achieved 3, 5, 6
• This can decrease vomiting and help avoid the need for intravenous fluids, though it may increase episodes of diarrhea 6

Probiotics

• Can be used to shorten the duration of diarrhea 6

Zinc Supplementation

• Recommended for children 6 months to 5 years of age who reside in countries with high zinc deficiency prevalence or show signs of malnutrition 3

Critical Pitfalls to Avoid

• Never use popular beverages (apple juice, Gatorade, commercial soft drinks) for rehydration—they have inappropriate electrolyte composition and osmolarity 1, 2
• Never withhold food or use outdated "clear liquids only" approach—this is nutritionally harmful and prolongs diarrhea 2
• Antimotility drugs (loperamide) are absolutely contraindicated in all children <18 years of age due to risks of respiratory depression and serious cardiac adverse reactions 3
• Do not use hypotonic solutions for initial rehydration in severe dehydration as they worsen electrolyte imbalances 7

Hospitalization Criteria

Reserve hospitalization for: 2

• Severe dehydration with signs of shock
• Altered mental status or inability to protect airway
• Ileus preventing oral intake
• Failure of oral rehydration therapy plus antiemetic

Evidence Supporting Oral Over Intravenous Therapy

The evidence strongly supports oral rehydration as equally effective to intravenous therapy for mild to moderate dehydration. A Cochrane review of 17 trials (1811 children) found that oral rehydration had only a 4% treatment failure rate requiring IV therapy, resulted in shorter hospital stays (mean difference -1.2 days), and had no clinically important differences in weight gain, duration of diarrhea, or electrolyte abnormalities compared to IV therapy. 8 Additional randomized trials confirm shorter emergency department stays (225 vs 358 minutes), less staff time required, and higher parental satisfaction with oral rehydration. 9