Is DNS (0.45% NS + 5% Dextrose) Appropriate for Maintenance in Pediatric Acute Gastroenteritis?
No, DNS (0.45% Normal Saline with 5% dextrose) should not be used as maintenance fluid in children with acute gastroenteritis—oral rehydration solution (ORS) is the recommended maintenance therapy after initial stabilization. 1, 2
The Correct Maintenance Fluid Approach
Oral rehydration solution is the primary maintenance fluid for children with acute gastroenteritis, not intravenous fluids like DNS. 1, 2 The American Academy of Pediatrics explicitly recommends transitioning immediately to ORS as the primary maintenance fluid after any initial stabilization, administering 120-240 mL ORS for each diarrheal stool or vomiting episode (up to ~1 L/day), while resuming an age-appropriate normal diet. 2
Why ORS Instead of IV Maintenance Fluids
The fundamental issue is that acute gastroenteritis management centers on oral rehydration therapy, not intravenous maintenance fluids. 1, 2 The guidelines are clear:
- For mild dehydration (3-5% deficit): Administer 50 mL/kg of ORS over 2-4 hours 1, 3
- For moderate dehydration (6-9% deficit): Administer 100 mL/kg of ORS over 2-4 hours 1, 3
- For severe dehydration (≥10% deficit): Use immediate IV rehydration with isotonic fluids (lactated Ringer's or normal saline) until pulse, perfusion, and mental status normalize, then transition to oral rehydration 1, 3
The Role of IV Fluids is Limited
Intravenous fluids are reserved for severe dehydration with shock or near-shock, and even then, the goal is rapid stabilization followed by transition to ORS. 1, 3 Hospitalization and IV fluids are only recommended for children who do not respond to oral rehydration therapy plus an antiemetic, or patients with severe dehydration. 4
Ongoing Loss Replacement (The True "Maintenance")
After initial rehydration, the maintenance phase involves:
- 10 mL/kg of ORS for each watery stool 1, 3, 2
- 2 mL/kg of ORS for each vomiting episode 1, 3, 2
- Continue until diarrhea and vomiting resolve 1
For a typical 20 kg child, this translates to 120-240 mL ORS per diarrheal stool and approximately 74 mL for each vomiting episode, up to approximately 1 L/day total. 2
ORS Composition Matters
Use reduced osmolarity ORS (total osmolarity <250 mmol/L) such as Pedialyte, CeraLyte, or Enfalac Lytren. 2 The American Academy of Pediatrics recommends:
Never use apple juice, Gatorade, or soft drinks as these are physiologically inappropriate. 2
When Vomiting Complicates Oral Intake
If vomiting is present, administer small volumes of ORS (5-10 mL) every 1-2 minutes using a spoon or syringe, gradually increasing the amount. 1, 3 A common pitfall is allowing a thirsty child to drink large volumes of ORS ad libitum, which may worsen vomiting. 1
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. 1, 5 This can improve tolerance of ORS and reduce the need for IV therapy. 2
Resume Normal Diet Immediately
The American Academy of Pediatrics recommends resuming age-appropriate normal diet immediately during or right after rehydration—do not withhold food or use restrictive diets. 2 Recommended foods include starches, cereals, yogurt, fruits, and vegetables; avoid foods high in simple sugars and fats. 1, 2
Common Pitfalls to Avoid
- Do not default to IV maintenance fluids when the child can tolerate oral intake 2
- Do not use antimotility drugs (loperamide) in children <18 years—they are absolutely contraindicated 1, 3
- Do not use traditional "clear liquids" approach—it is inadequate 6
- Do not allow ad libitum drinking of ORS in vomiting children—use small, frequent volumes 1
When IV Fluids Are Actually Needed
Return to IV therapy only if there is: