Peripheral Administration of Hypertonic Saline
Hypertonic saline can be safely administered peripherally at rates up to 50 mL/hour for continuous infusions and up to 999 mL/hour for bolus administration with appropriate monitoring and precautions.
Administration Rates and Safety
Continuous Infusions
- Maximum recommended rate: 50 mL/hour for 3% hypertonic saline 1
- Appropriate catheter size: 16-20 gauge peripheral IV 1
- Duration: Can be safely administered for periods ranging from 1-124 hours 1
Bolus Administration
- Bolus doses can be administered at rates up to 999 mL/hour through peripheral IVs 2
- Median administration rate in emergency situations: 760 mL/hour (IQR 500-999) 2
- No episodes of extravasation or phlebitis were reported even at these high rates 2
Complication Rates
Peripheral administration of 3% hypertonic saline carries a low risk of complications:
- Infiltration: 3.3% (95% CI = 1.8-5.1%) 3
- Phlebitis: 6.2% (95% CI = 1.1-14.3%) 3
- Erythema: 2.3% (95% CI = 0.3-5.4%) 3
- Edema: 1.8% (95% CI = 0.0-6.2%) 3
- Venous thrombosis: 1% (95% CI = 0.0-4.8%) 3
Best Practices for Administration
IV Access Considerations
- Preferred catheter size: 18 gauge (range 16-20 gauge) 2
- Optimal placement site: Antecubital fossa (48.6% of successful administrations) 2
- Avoid small distal veins in hands or feet
Monitoring Requirements
- Serum sodium should be measured within 6 hours after administration 4
- No additional doses should be given if serum sodium is ≥155 mmol/L 4
- Monitor for signs of infiltration, erythema, swelling, or phlebitis at the IV site
Osmolarity Considerations
- For peripheral administration, solutions with osmolarity <900 mOsm/L are generally recommended 5
- 3% hypertonic saline has an osmolarity of 1026 mOsm/L 5 but has been shown to be safe peripherally despite exceeding this threshold
Clinical Implications
The traditional practice of requiring central venous access for hypertonic saline administration may be unnecessarily restrictive. The concern regarding peripheral administration risks appears to be overstated based on current evidence 1, 3, 6. Peripheral administration offers several advantages:
- Avoids complications associated with central line placement (pneumothorax, arterial injury, bloodstream infection)
- Allows for more rapid treatment in emergency situations
- Reduces delays in therapy initiation
Cautions and Contraindications
- Patients with renal or cardiac compromise require more frequent monitoring 4
- Maximum change in serum osmolality should not exceed 3 mOsm/kg/hour 4
- For sodium correction, maintain a rate of 0.5-1 mEq/L/hour 4
The evidence clearly demonstrates that peripheral administration of hypertonic saline is a safe and effective option for both continuous infusions and bolus administration when appropriate monitoring and precautions are in place.