Severe Dehydration in Pediatrics: Immediate Intravenous Resuscitation
For severe dehydration in pediatric patients, immediately administer intravenous isotonic crystalloid boluses of 20 mL/kg body weight (using lactated Ringer's or normal saline) until pulse, perfusion, and mental status normalize, then transition to oral rehydration solution once the child is stable. 1
Initial Recognition and Assessment
Severe dehydration is defined as ≥10% fluid deficit with clinical signs of shock or pre-shock, including:
- Altered mental status
- Abnormal pulse (weak, rapid, or absent peripheral pulses)
- Poor perfusion with prolonged capillary refill
- Decreased or absent urine output 1, 2
Critical caveat: Signs of dehydration may be masked in hypernatremic patients, so maintain high clinical suspicion even when classic signs are absent. 1
Immediate Intravenous Resuscitation Protocol
Standard Pediatric Patients (Children and Adolescents)
Administer 20 mL/kg boluses of isotonic crystalloid (0.9% saline or lactated Ringer's) rapidly until clinical parameters normalize: 1
- Continue boluses until pulse strength improves
- Perfusion returns to normal
- Mental status clears
- Patient awakens and has no aspiration risk 1
Balanced crystalloid solutions (Ringer's lactate) likely reduce hospital stay slightly compared to 0.9% saline (by approximately 0.35 days) and may produce better biochemical outcomes. 3
Special Population: Malnourished Infants
Use smaller-volume, frequent boluses of 10 mL/kg body weight due to reduced cardiac capacity to handle larger volume resuscitation. 1 This prevents fluid overload in infants with compromised cardiovascular reserve.
Fluid Administration Rate
For the initial resuscitation phase, administer 60-100 mL/kg of 0.9% saline in the first 2-4 hours to restore circulation in severe dehydration. 4 This rapid approach is safe and effective for correcting shock.
Electrolyte Management During Resuscitation
- Adjust electrolytes based on laboratory values obtained during initial assessment 1
- Administer dextrose if hypoglycemia is present or suspected 1
- For oliguric patients with severe acidosis, consider physiological bicarbonate dosing to correct blood pH to 7.25 4
- Add 20 mEq/L potassium to rehydration solutions once urine output is established, which permits repair of cellular potassium deficits without hyperkalemia risk 4
Transition to Oral Rehydration
Once the patient is stabilized (normal pulse, perfusion, mental status), transition to oral rehydration solution (ORS) to replace the remaining fluid deficit. 1 This approach:
- Reduces total IV fluid requirements
- Allows for safer completion of rehydration
- Enables earlier discharge in most cases 1
When to Continue IV Therapy
Continue intravenous fluids if: 1
- Persistent altered mental status
- Risk factors for aspiration remain
- Evidence of ileus
- Failure of ORS therapy
- Ongoing severe vomiting despite initial resuscitation
Type of Dehydration Considerations
Isonatremic Dehydration (Most Common)
After initial resuscitation, use 5% dextrose in 0.45% saline with 20 mEq/L KCl over 24 hours for remaining deficit and maintenance. 4
Hypernatremic Dehydration
Slow correction is essential: Use 5% dextrose in 0.2% saline with 20 mEq/L KCl over 2-3 days to avoid cerebral edema. 4 Never correct hypernatremia rapidly.
Hyponatremic Dehydration
Alternate 0.9% saline and 0.45% saline in 1:1 ratio in 5% dextrose with 20 mEq/L KCl over 24 hours. 4
Ongoing Loss Replacement
After initial resuscitation, replace ongoing losses with ORS: 1, 5
- 10 mL/kg ORS for each diarrheal stool
- 2 mL/kg ORS for each vomiting episode
- For infants <10 kg: 60-120 mL per episode (up to ~500 mL/day)
- For children >10 kg: 120-240 mL per episode (up to ~1 L/day) 1
Monitoring and Reassessment
Continuously monitor during resuscitation: 1
- Pulse quality and rate
- Capillary refill time
- Mental status
- Urine output
- Perfusion parameters
Reassess after each bolus to determine need for additional fluid administration. 1
Feeding Resumption
- Breastfed infants should continue nursing throughout the illness, even during severe dehydration treatment 1, 5
- Resume age-appropriate normal diet as soon as the child tolerates oral intake 1
- Full-strength formula can be given immediately after rehydration; dilution provides no benefit 1
Common Pitfalls to Avoid
- Do not use hypotonic maintenance fluids during acute resuscitation of severe dehydration—only isotonic crystalloids 1
- Do not use popular beverages (apple juice, Gatorade, soft drinks) for rehydration—these lack appropriate electrolyte composition 1
- Do not delay IV access in truly severe dehydration to attempt oral rehydration first 1
- Do not correct hypernatremia rapidly—this causes cerebral edema 4
- Do not overlook malnourished infants who require modified bolus volumes 1