IV Fluid Management for Pediatric Dehydration
Severe Dehydration (≥10% fluid deficit, shock, or altered mental status)
For severe dehydration, immediately administer IV boluses of 20 mL/kg of isotonic crystalloid (Ringer's lactate or normal saline) and repeat until pulse, perfusion, and mental status normalize, then transition to oral rehydration solution once the patient is alert and has no ileus. 1
Initial Resuscitation
- Administer 20 mL/kg boluses of Ringer's lactate or normal saline (isotonic crystalloid) rapidly 1
- Repeat boluses until vital signs stabilize: normal pulse, adequate perfusion, and return of normal mental status 1
- May require two IV lines or alternative access (venous cutdown, femoral vein, intraosseous) for critically ill children 1
- Balanced crystalloid solutions like Ringer's lactate likely reduce hospital stay slightly compared to normal saline (by approximately 0.35 days) and reduce risk of hypokalemia 2
Transition to Oral Rehydration
- Once consciousness returns and the patient is alert with no aspiration risk or ileus, switch to oral rehydration solution (ORS) for the remaining fluid deficit 1
- Continue frequent reassessment of hydration status every 2-4 hours 1
Critical Contraindication
- Never use ORS if ileus is present—continue IV isotonic fluids until bowel function returns 1, 3
- Discontinue all antimotility agents, anticholinergics, and opioids that worsen ileus 4, 3
Moderate Dehydration (6-9% fluid deficit)
Oral rehydration solution at 100 mL/kg over 2-4 hours is first-line therapy for moderate dehydration without shock or altered mental status. 1, 5
Oral Rehydration Protocol
- Administer ORS containing 50-90 mEq/L sodium at 100 mL/kg over 2-4 hours 1, 5
- Start with small volumes (5 mL by teaspoon, syringe, or dropper) and gradually increase as tolerated 1
- Reassess after 2-4 hours: if still dehydrated, reestimate deficit and restart rehydration 1
When IV Therapy is Needed
- Use IV rehydration if ORS fails, persistent vomiting prevents oral intake, or severe metabolic acidosis is present (bicarbonate ≤13 mEq/L) 1, 6
- Rapid IV rehydration with 20-30 mL/kg isotonic crystalloid over 1-2 hours corrects dehydration and often resolves vomiting, allowing transition to oral fluids 6, 7
- Children with bicarbonate >13 mEq/L typically tolerate oral fluids after rapid IV rehydration (85% success rate), while those with bicarbonate ≤13 mEq/L usually require admission 6
Ongoing Loss Replacement
Replace ongoing stool and vomit losses continuously with ORS throughout both rehydration and maintenance phases. 1
Replacement Volumes
- 10 mL/kg ORS for each watery/loose stool 1, 5
- 2 mL/kg ORS for each vomiting episode 1, 5
- If losses can be measured accurately, give 1 mL ORS per gram of diarrheal stool 1
Infants and Children Specific Dosing
- <10 kg body weight: 60-120 mL ORS per diarrheal stool or vomiting episode (up to ~500 mL/day) 1
10 kg body weight: 120-240 mL ORS per diarrheal stool or vomiting episode (up to ~1 L/day) 1
Maintenance Phase After Rehydration
Resume age-appropriate normal diet immediately after rehydration is complete while continuing ORS for ongoing losses. 1, 5
Nutritional Management
- Breast-fed infants: Continue nursing on demand throughout illness 1
- Bottle-fed infants: Use full-strength lactose-free or lactose-reduced formula immediately; if unavailable, full-strength lactose-containing formula is acceptable 1
- Older children: Resume usual diet with starches, cereals, yogurt, fruits, and vegetables; avoid foods high in simple sugars and fats 1
Common Pitfall
- Do not dilute formula—this provides no benefit and delays nutritional recovery 1
- True lactose intolerance (worsening diarrhea with lactose reintroduction) is uncommon; low stool pH or reducing substances alone without clinical symptoms do not indicate lactose intolerance 1
Electrolyte Monitoring and Correction
Monitor and correct electrolyte abnormalities, particularly potassium, during IV rehydration. 1, 4, 8
- Add 20 mEq/L potassium chloride to IV rehydration solutions to repair cellular potassium deficits without hyperkalemia risk 8
- Check serum electrolytes every 24-48 hours in severe cases or when clinical signs suggest abnormalities 4
- Adjust dextrose based on chemistry values 1
Key Clinical Monitoring Parameters
Assess pulse, perfusion, mental status, and hydration status frequently during rehydration. 1