Management Protocol for Hypernatremic Dehydration in NICU
The management of hypernatremic dehydration in neonates requires careful fluid administration with 5% dextrose in water as the primary rehydration fluid, avoiding normal saline which can worsen hypernatremia due to its high sodium content. 1
Initial Assessment
- Evaluate clinical status, body weight, and estimate body composition 1
- Check blood electrolyte concentrations and acid-base status 1
- Monitor fluid and electrolyte balance (urine output, urine specific gravity/osmolarity, urine electrolytes) 1
- Assess hematocrit and blood urea nitrogen 1
- Determine severity of dehydration based on clinical signs 1
Rehydration Protocol
Fluid Selection
- Avoid salt-containing solutions, especially 0.9% NaCl as they provide a large renal osmotic load that exceeds typical urine osmolality in hypernatremic states 1
- Use 5% dextrose in water as the primary rehydration fluid as it delivers no renal osmotic load 1
- For severe dehydration with shock, use plasma expanding fluids initially before proceeding with rehydration 2
Fluid Rate Calculation
- Calculate initial rate based on physiological demand 1:
- First 10 kg: 100 ml/kg/24h
- 10-20 kg: 50 ml/kg/24h (additional)
- Remaining weight: 20 ml/kg/24h (additional)
Correction Rate
- Target a slow reduction in serum sodium of 0.5 mmol/L/hour 2
- Do not exceed correction rate of 10-15 mmol/L/24h to avoid cerebral edema, seizures, and neurological injury 1
- A cumulative rate of 5.9 ml/kg/hr of IV fluid administration typically reduces serum sodium by approximately 0.65 mEq/L/hr 3
Monitoring During Rehydration
- Monitor serum electrolytes and weight daily during initial days of treatment 1
- Adjust monitoring intervals based on clinical status and patient stability 1
- Target normalization of serum sodium within 48-72 hours 1
- Watch for signs of cerebral edema (altered mental status, seizures) during correction 1
Special Considerations
For Oral Rehydration (if applicable)
- For mild to moderate hypernatremic dehydration without altered mental status or shock, oral rehydration may be considered 4
- Use glucose-electrolyte solution with 75-90 mmol/L sodium, administered at a volume equivalent to twice the estimated fluid deficit 5
- Consider combining oral glucose/electrolyte solution (2/3) with plain water (1/3) for hypernatremic infants 4
For Severe Cases
- Low threshold for intravenous rehydration when oral rehydration has failed 1
- In cases with seizures, altered mental status, or shock, avoid oral rehydration 5
- For patients with secondary nephrogenic diabetes insipidus, avoid salt supplementation 1
Prevention of Complications
- Monitor for cerebral edema, seizures, and neurological injury during correction 1
- Ensure adequate caloric intake alongside rehydration, especially in infants 1
- For patients requiring prolonged fluid therapy, monitor for electrolyte imbalances and adjust accordingly 1
- Consider gastric acid inhibitors if there is significant vomiting during rehydration 1
Common Pitfalls to Avoid
- Using normal saline (0.9% NaCl) as primary rehydration fluid, which can worsen hypernatremia 1
- Correcting serum sodium too rapidly (>0.5 mmol/L/hour), which risks cerebral edema and seizures 2
- Failing to monitor serum electrolytes frequently during initial rehydration 1
- Inadequate fluid volume calculation that doesn't account for ongoing losses 1
- Neglecting to adjust therapy based on clinical response and laboratory values 1