What is the recommended infusion rate for 3% sodium chloride (hypertonic saline)?

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Recommended Infusion Rate for 3% Sodium Chloride

For severe symptomatic hyponatremia, 3% sodium chloride should be administered at a rate of 1-2 mmol/L per hour until symptoms abate, with a maximum correction of 12 mmol/L in 24 hours or 18 mmol/L in 48 hours. 1

Adult Infusion Rates

Severe Symptomatic Hyponatremia

  • Initial bolus: 100-150 mL of 3% sodium chloride over 10-20 minutes for patients with severe neurological symptoms 2
  • Continuous infusion: Calculate using formula: body weight (kg) × desired rate of increase in sodium (mmol/L per hour) 1
  • Target rate of correction: 1-2 mmol/L per hour until symptoms improve 1
  • Maximum correction limits: 6 mmol/L in 6 hours, 12 mmol/L in 24 hours, or 18 mmol/L in 48 hours 3

Mild to Moderate Hyponatremia

  • For less severe symptoms: 0.5 ml/kg/h of 3% sodium chloride 4
  • Peripheral administration is safe at rates up to 999 mL/h in emergency situations 5

Monitoring Requirements

  • Measure serum sodium every 2-4 hours during active correction 3
  • Monitor for neurological status changes throughout treatment 3
  • Calculate corrected serum sodium for hyperglycemia (add 1.6 mEq to sodium value for each 100 mg/dL glucose >100 mg/dL) 3
  • Monitor serum osmolality to ensure changes do not exceed 3 mOsm/kg/h 3

Safety Considerations

  • Avoid correction exceeding 12 mmol/L in 24 hours to prevent osmotic demyelination syndrome 1
  • Be prepared to administer hypotonic fluids (e.g., D5W) if overcorrection occurs 2
  • Ensure renal function is adequate before adding potassium to infusions 3
  • Peripheral administration of 3% sodium chloride is safe even at rapid rates (≥250 mL/h) in emergency situations 5

Special Populations

  • Pediatric patients: Use more conservative initial rates (10-20 mL/kg/h) with careful monitoring 3
  • Patients with cardiac or renal compromise: Require more frequent monitoring of serum osmolality and mental status 3

Practical Administration Tips

  • 3% sodium chloride can be safely administered through peripheral IV lines 5
  • In emergencies when IV access is limited, hourly oral sodium chloride tablets may be considered as an alternative to IV 3% sodium chloride 4
  • A 500 mL continuous infusion of 3% sodium chloride over 6 hours has been shown to be effective and safe for hyponatremic encephalopathy 6

Following these guidelines for 3% sodium chloride administration ensures effective treatment while minimizing the risk of complications from either under-correction or over-correction of serum sodium levels.

References

Research

Hyponatraemia-treatment standard 2024.

Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, 2024

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Treatment of hyponatremic encephalopathy with a 3% sodium chloride protocol: a case series.

American journal of kidney diseases : the official journal of the National Kidney Foundation, 2015

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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