When is Dextrose Normal Saline (DNS) indicated?

Indications for Dextrose Normal Saline (DNS)

Dextrose Normal Saline (DNS) is primarily indicated for patients with hypovolemic hypernatremia, maintenance fluid therapy in patients requiring both electrolytes and glucose, and as maintenance fluid in burn patients to prevent hypoglycemia and maintain electrolyte balance.

Primary Indications

1. Hypovolemic Hypernatremia Management

• After initial stabilization with isotonic saline (0.9% NaCl), DNS (5% dextrose in 0.9% normal saline) is appropriate for patients with hypovolemic hypernatremia 1
• Provides both volume replacement and glucose to prevent hypoglycemia
• Particularly useful in elderly patients with elevated serum osmolality (>300 mOsm/kg) who appear unwell 1

2. Maintenance Fluid Therapy

• Indicated as maintenance fluid in patients requiring both electrolytes and glucose supplementation
• Useful in patients whose oral intake is restricted or inadequate to maintain nutritional requirements 2
• Provides both sodium (154 mEq/L) and glucose (5%) to meet daily requirements

3. Burn Management

• Recommended as maintenance fluid in combination with Ringer's lactate in acute burn patients 3
• Helps maintain sodium levels and blood glucose within normal ranges
• Prevents hyponatremia that can occur when using Ringer's lactate alone 3

4. Severe Dehydration with Diarrhea

• For patients with severe dehydration due to infectious diarrhea who cannot tolerate oral rehydration
• After initial resuscitation with isotonic fluids, DNS can be used for maintenance 4
• The 2017 IDSA guidelines recommend 5% dextrose 0.25 normal saline with potassium chloride for maintenance in patients with severe dehydration who cannot drink 4

Clinical Decision Algorithm

1. Assess hydration status and electrolytes:

   • If severely dehydrated: Begin with isotonic fluids (0.9% NaCl or Ringer's lactate)
   • Once hemodynamically stable, consider DNS for maintenance

2. Consider specific clinical scenarios:

   • Burn patients: Use DNS as maintenance fluid alongside Ringer's lactate for resuscitation
   • Patients with restricted oral intake: DNS provides both calories and electrolytes
   • Patients with hypernatremia: DNS helps correct sodium levels while providing glucose

3. Monitor for complications:

   • Check blood glucose regularly to prevent hyperglycemia
   • Monitor electrolytes, especially in patients at risk for electrolyte disturbances
   • Assess fluid status to prevent volume overload

Contraindications and Precautions

• Not recommended as initial resuscitation fluid in hypovolemic shock (use isotonic fluids without dextrose) 1
• Use with caution in patients at risk for cerebral edema, as dextrose solutions can worsen cerebral edema 1
• Not appropriate for routine maintenance in non-diabetic patients undergoing elective surgery, as it may cause transient hyperglycemia 5
• Avoid in patients with diabetes without close glucose monitoring

Special Considerations for Pediatric Patients

• Recent evidence suggests isotonic fluids (0.9% saline with 5% dextrose) may be safer than hypotonic fluids (0.45% saline with 5% dextrose) for maintenance therapy in hospitalized children 6
• Isotonic fluids have lower risk of iatrogenic hyponatremia compared to hypotonic solutions 6
• For children with severe dehydration from diarrhea, after initial resuscitation with isotonic fluids, maintenance can include dextrose-containing solutions 4

Administration Guidelines

• For maintenance therapy, administer at standard maintenance rates
• For hypovolemic hypernatremia, the rate should be calculated to correct sodium at a safe rate (not exceeding 3 mOsm/kg/h) 1
• Slow infusion of hypertonic solutions is essential to ensure proper utilization of dextrose and avoid hyperglycemia 2

DNS provides both glucose and electrolytes, making it suitable for specific clinical scenarios where both components are needed. However, its use should be guided by the patient's clinical condition, with appropriate monitoring of glucose levels and electrolyte status.