Can D5 (Dextrose 5%) be given to a malnourished person?

D5 Administration in Malnourished Patients

D5 (5% dextrose) can be given to malnourished patients, but only as a short-term bridge measure (typically <12 hours) and must be accompanied by thiamine administration to prevent Wernicke's encephalopathy—it should never be used as the sole nutritional intervention. 1, 2

Critical Safety Requirements Before D5 Administration

Thiamine must be administered prior to starting any glucose infusion in malnourished patients to reduce the risk of precipitating Wernicke's encephalopathy. 1, 2 This is non-negotiable in the malnourished population.

Monitoring for Refeeding Syndrome

When initiating any nutritional support (including D5) in severely malnourished patients, you must monitor for refeeding syndrome: 2, 3

• Check phosphate, potassium, and magnesium levels before starting and daily for the first 3-5 days 2
• Monitor blood glucose regularly to detect both hypoglycemia and hyperglycemia 1, 2
• Refeeding syndrome can present with hypoglycemia, hypophosphatemia, hypomagnesemia, and hypokalemia 3

When D5 is Appropriate (Limited Scenarios)

D5 may be used for short-term glucose provision when patients must abstain from food for more than 12 hours, at a dose of 2-3 g/kg/day. 1, 2 This represents a temporizing measure only, not definitive nutritional support.

Why D5 Alone is Inadequate for Malnutrition

Using D5 alone without addressing protein, lipid, and micronutrient needs is harmful. 2 Here's what malnourished patients actually require:

Complete Nutritional Support Components

• Energy: 1.3x Resting Energy Expenditure, with glucose covering only 50-60% of non-protein energy requirements 2
• Protein: Amino acids at 1.2-1.5 g/kg/day 2
• Lipids: Remaining energy needs from fat emulsions 2
• Micronutrients: Water-soluble vitamins and trace elements daily from day one 2

Appropriate Nutritional Interventions by Severity

For moderately to severely malnourished patients (NRS-2002 ≥5) who cannot be fed orally or enterally, parenteral nutrition should be started immediately. 4, 2 The evidence shows:

• Enteral nutrition is preferred over parenteral nutrition when the GI tract is functional 4
• Early enteral feeding (within 24-48 hours) reduces infectious complications (RR 0.50, CI 0.37-0.67) and shortens ICU stay compared to early parenteral nutrition 4
• Preoperative nutritional support for 7-14 days is recommended for severely malnourished surgical patients (NRS ≥5) 4

Peripheral vs Central Administration

If D5 must be used peripherally as a bridge, it can be given without dilution. However, D50 (50% dextrose) must be diluted for peripheral administration to prevent vein irritation. 2

Clinical Decision Algorithm

1. Assess malnutrition severity using Subjective Global Assessment (SGA) or NRS-2002 4, 2
2. Administer thiamine immediately before any glucose 1, 2
3. If oral intake possible: Dietary counseling ± oral nutritional supplements for minimum 3 months 4
4. If oral intake inadequate and GI tract functional: Enteral tube feeding 4
5. If GI tract non-functional or contraindicated: Total parenteral nutrition with complete macro/micronutrients 4, 2
6. D5 only if: Temporary bridge (<12 hours) while arranging definitive nutritional support 1, 2

Common Pitfalls to Avoid

• Never use D5 as definitive nutritional therapy—it provides only glucose without protein, essential fatty acids, or micronutrients 2
• Failing to give thiamine before glucose can precipitate Wernicke's encephalopathy in malnourished patients 1, 2
• Not monitoring for refeeding syndrome when initiating any nutritional support in severely malnourished patients 2, 3
• Delaying enteral nutrition when the GI tract is functional—early EN reduces complications even in apparent ileus 4