Should 0.2% NaCl Be Used for Treating Hypernatremia in Children?
No, 0.2% NaCl should NOT be used for treating hypernatremia in children—this concentration is far too hypotonic and risks overly rapid correction leading to cerebral edema and death. 1
Appropriate Hypotonic Fluid Selection for Hypernatremia
For frank hypernatremia correction in children, use 0.45% NaCl (half-normal saline) with 5% dextrose, not 0.2% NaCl. 1 The American Diabetes Association guidelines specifically recommend 0.45% NaCl as the appropriate hypotonic fluid for hypernatremia correction. 1
- 0.2% NaCl is excessively hypotonic and will cause dangerously rapid sodium correction, particularly in children who are more vulnerable to osmotic shifts than adults. 2
- The addition of 5% dextrose prevents hypoglycemia while providing necessary free water for sodium dilution. 1
Critical Rate of Correction to Prevent Cerebral Edema
The serum sodium must decrease no faster than 10 mEq/L per 24 hours (approximately 0.5 mEq/L per hour) to avoid fatal cerebral edema. 1, 2
- Monitor serum osmolality changes, ensuring they do not exceed 3 mOsm/kg H₂O per hour. 1
- Too rapid correction with overly hypotonic fluids like 0.2% NaCl is the primary cause of treatment-related mortality in hypernatremia. 2, 3
- Children who survive extreme hypernatremia (sodium >200 mEq/L) with appropriate gradual correction can have complete neurological recovery, but rapid correction is uniformly catastrophic. 4, 5
Essential Monitoring Protocol
Check serum sodium every 4-6 hours initially, then every 6-8 hours once a stable downward trend is established. 1
- Assess volume status clinically: weight, urine output, blood pressure, and signs of fluid overload. 1
- If sodium is decreasing faster than 0.5 mEq/L per hour, immediately slow or stop hypotonic fluid administration. 1
Why 0.2% NaCl Is Contraindicated
0.2% NaCl contains only 34 mEq/L of sodium—this is so hypotonic that it will cause uncontrolled rapid sodium correction in hypernatremic children. 6
- The 2018 American Academy of Pediatrics guidelines specifically warn against using very hypotonic fluids (0.18% NaCl was studied and found problematic), noting that patients with renal concentrating defects could develop complications. 6
- 0.2% NaCl is actually used to PREVENT hypernatremia in maintenance fluid therapy, not to treat established hypernatremia. 6
Special Considerations in Pediatric Hypernatremia
Children with hypernatremia from salt poisoning or inadequate free water intake require particularly careful management. 3, 4
- Initial serum sodium concentrations >200 mEq/L have worse prognosis, but age is the most important prognostic factor—very young patients have better survival rates with appropriate treatment. 3
- Breastfed infants are at high risk for hypernatremia from lactation failure and require close monitoring. 2, 5
- In extreme hypernatremia (sodium >210 mEq/L) with oliguric renal failure, peritoneal dialysis combined with hypotonic IV fluids may be necessary to achieve controlled sodium correction. 5
Common Fatal Pitfalls to Avoid
Never use 0.2% NaCl or any fluid more hypotonic than 0.45% NaCl for hypernatremia correction—this will cause cerebral edema. 1, 2
- Do not attempt to correct hypernatremia faster than 10 mEq/L per 24 hours regardless of initial severity. 1, 2
- Never use isotonic (0.9%) saline for hypernatremia treatment, as it will worsen the condition. 1
- Avoid fluid restriction in hypernatremia—this is a hyponatremia management strategy and is contraindicated here. 1