What is the management for a patient with hypernatremia on hypertonic saline?

Management of Hypernatremia (Sodium 157 mmol/L) in a Patient Receiving Hypertonic Saline

Stop the hypertonic saline infusion immediately, as the serum sodium of 157 mmol/L exceeds the recommended maximum target of 155 mmol/L and has persisted for 3 days, placing the patient at risk for serious complications including thrombocytopenia, renal failure, and fatal arrhythmias. 1, 2, 3

Immediate Actions

Discontinue Hypertonic Saline

• Stop all hypertonic saline administration immediately when sodium exceeds 155 mmol/L 1, 2
• The target range for hypertonic saline therapy is 145-155 mmol/L, and levels should not exceed 155-160 mmol/L to prevent complications 1, 2
• Re-administration should not occur until serum sodium concentration is confirmed <155 mmol/L 1, 2, 4

Monitor for Complications

• Check serum sodium within 6 hours of stopping the infusion 1, 2, 4
• Monitor for signs of hypernatremia complications including:
  • Cardiac arrhythmias (QT prolongation, ventricular tachycardia) 3
  • Thrombocytopenia, renal failure, neutropenia, and acute respiratory distress syndrome (especially if sodium >170 mEq/L for >72 hours) 1
• Obtain baseline ECG to assess for QT prolongation or other arrhythmias 3

Correction Strategy

Gradual Sodium Reduction

• Avoid rapid correction of sodium levels - do not exceed 10 mmol/L sodium correction per 24 hours to prevent osmotic demyelination syndrome 1
• Use hypotonic fluids (5% dextrose or 0.45% saline) to gradually lower sodium 3
• Calculate free water deficit and replace over 36-48 hours 3

Ongoing Monitoring

• Check serum sodium every 6 hours initially during correction phase 1, 4
• Monitor fluid balance, urine output, and osmolality 1
• Continue ICP monitoring if the original indication for hypertonic saline was elevated intracranial pressure 4

Reassess Original Indication

Evaluate Need for Continued Therapy

• Determine if the clinical indication for hypertonic saline (elevated ICP, cerebral edema) has resolved 4
• If ICP control is still needed and sodium normalizes to <155 mmol/L, consider restarting at a lower infusion rate with more frequent monitoring 1, 4
• Consider alternative ICP management strategies (head-of-bed elevation, analgesia, sedation) 1

Critical Safety Considerations

High-Risk Complications

• Extreme hypernatremia (>190 mmol/L) carries mortality rates exceeding 60% 3
• Fatal arrhythmias have been reported with extreme hypernatremia, particularly QT prolongation leading to ventricular tachycardia 3
• Sustained sodium >170 mEq/L for >72 hours significantly increases risk of multiple organ complications 1

Common Pitfall to Avoid

• Do not continue hypertonic saline simply because the patient "was on it" - the sodium level of 157 mmol/L for 3 days indicates inadequate monitoring and dose adjustment 1, 2
• Measuring sodium less frequently than every 6 hours during active therapy is a critical error 1, 4