12.1 Nutrition Therapy for Wound Healing
Key Takeaways
- For adults with pressure injuries who are malnourished or at risk, the international guideline recommends about 30 to 35 kcal/kg/day of energy and 1.25 to 1.5 g/kg/day of protein, adjusted for weight change, medical conditions, and goals of care.
- High-calorie, high-protein oral nutritional supplements enriched with arginine, zinc, and antioxidants are suggested for adults with stage 2 or greater pressure injuries who are malnourished or at risk; in the OEPS trial they improved area reduction at 8 weeks.
- Supplement individual micronutrients only when deficiency is suspected or confirmed: for example, vitamin C for scurvy, zinc for short courses when low (long-term high-dose zinc causes copper deficiency), and vitamin D when deficient.
- Before feeding a severely malnourished patient, assess refeeding syndrome risk; start nutrition cautiously, give thiamine before feeding, and monitor phosphate, potassium, and magnesium closely during the first days.
- Nutrition plans must fit comorbidities and goals: glycemic control in diabetes, individualized protein targets in chronic kidney disease and dialysis, fluid needs in heavy exudate or fever, and comfort-focused eating near the end of life.
12.1 Nutrition Therapy for Wound Healing
Core Clinical Principle: A wound cannot be built from nothing. Once malnutrition or risk is identified, the plan should meet energy and protein needs, correct real deficiencies, keep the patient hydrated, and fit the patient's other conditions and goals, with a registered dietitian leading the details and the wound team tracking results.
The CWSP outline lists nutrition in Patient Management, and addressing and managing nutritional deficits is a listed task. Nutrition screening and diagnosis are covered in the assessment chapter, and the biology of individual micronutrients is covered with systemic barriers to healing.
Estimating Requirements
| Nutrient | Typical Target for Adults With Wounds | Adjust For |
|---|---|---|
| Energy | About 30 to 35 kcal/kg/day for adults with pressure injuries who are malnourished or at risk | Weight gain or loss goals, obesity (use adjusted weight or indirect calorimetry), critical illness |
| Protein | About 1.25 to 1.5 g/kg/day | Kidney function, dialysis, liver disease, large exudate losses, burns (higher needs) |
| Fluid | About 1 mL per kcal or roughly 30 mL/kg/day | Heart failure and kidney failure (restrict), fever, air-fluidized beds, heavy exudate (increase) |
Worked example: A 70-kg adult with a stage 4 pressure injury who is at nutritional risk needs about 70 × 30 = 2,100 to 70 × 35 = 2,450 kcal/day and about 70 × 1.25 = 88 to 70 × 1.5 = 105 g of protein/day, with about 2,100 to 2,450 mL of fluid if no restriction applies.
Major burns raise needs far above these values, and indirect calorimetry is the most accurate way to measure energy expenditure in critical illness.
Feeding Strategy
- Food first: Liberalize restrictive diets when possible, offer preferred foods, provide help with eating, treat oral problems, and schedule snacks.
- Oral nutritional supplements: Add high-calorie, high-protein supplements between meals when intake is inadequate.
- Enteral nutrition: Consider tube feeding when oral intake remains inadequate and it fits the patient's goals, after discussing benefits and burdens.
- Parenteral nutrition: Reserve for patients whose gastrointestinal tract cannot be used.
Wound-Specific Supplements
- Arginine, zinc, and antioxidants: In the OEPS trial (Cereda and colleagues, 2015), malnourished patients with stage 2 to 4 pressure injuries who received a high-calorie, high-protein supplement enriched with arginine, zinc, and antioxidants had greater pressure injury area reduction at 8 weeks (about 61% vs. 45%) than those receiving an equal-calorie, equal-protein formula without enrichment. The international guideline suggests these formulas for adults with stage 2 or greater pressure injuries who are malnourished or at risk.
- Hydrolyzed collagen and other amino acid products: Small studies suggest possible benefits, but the evidence is limited.
- Glutamine: Mainly studied in critical illness and burns, with mixed results; not routinely recommended for chronic wounds.
Micronutrients: Replace Deficiencies, Avoid Megadoses
| Nutrient | When to Supplement | Caution |
|---|---|---|
| Vitamin C | Scurvy or low intake (for example, restricted diets, alcohol use disorder) | Excess can raise kidney stone risk |
| Zinc | Confirmed or strongly suspected deficiency, for a limited course | Long-term high doses cause copper deficiency with anemia, neutropenia, and neuropathy |
| Vitamin A | Short courses to counter corticosteroid-impaired healing, or deficiency | Toxicity with prolonged high doses; avoid high doses in pregnancy |
| Vitamin D | Documented deficiency | Hypercalcemia with excess |
| Iron | Iron-deficiency anemia | Oral absorption falls with inflammation; intravenous iron may be needed |
| Multivitamin with minerals | Poor intake or multiple deficiencies | Reasonable low-risk baseline |
Refeeding Syndrome
When a starved patient starts eating, insulin release drives phosphate, potassium, and magnesium into cells and increases thiamine use. The result can be hypophosphatemia, arrhythmias, heart failure, respiratory failure, delirium, and Wernicke encephalopathy.
- High-risk patients: Very low BMI, little or no intake for many days, significant recent weight loss, low baseline electrolytes, chronic alcohol use, and conditions such as anorexia nervosa.
- Prevention: Check electrolytes before feeding; start with reduced calories (ASPEN consensus suggests about 100 to 150 g of dextrose or 10 to 20 kcal/kg in the first 24 hours) and advance gradually; give thiamine about 100 mg before feeding and continue for 5 to 7 days in high-risk patients; monitor and replace phosphate, potassium, and magnesium frequently for the first 72 hours or longer.
Special Populations
- Diabetes: Keep glucose controlled while meeting protein and energy needs; avoid overly restrictive diets that reduce intake. Hospital targets commonly aim for about 140 to 180 mg/dL.
- Chronic kidney disease not on dialysis: Protein goals are individualized with nephrology and the dietitian because low-protein diets slow kidney decline but may conflict with healing needs.
- Dialysis: Protein needs rise (commonly about 1.0 to 1.2 g/kg/day or more) because dialysis removes amino acids.
- Obesity: Patients can be malnourished; avoid aggressive calorie restriction during active wound healing, but preserve protein intake.
- After bariatric surgery: Replace protein, iron, B12, thiamine, copper, zinc, and fat-soluble vitamins as needed.
- End of life: Artificial nutrition rarely heals wounds in the last weeks of life; offer food for comfort and focus on symptom relief according to the patient's wishes.
Monitoring
- Weight weekly (or as appropriate), intake records, and tolerance of supplements.
- Wound measurements every 1 to 2 weeks to see whether the plan is working.
- Glucose, electrolytes, and kidney function as indicated.
- Avoid using prealbumin or albumin alone to judge repletion.
Clinical Traps
Trap 1: Megadosing Zinc for Months
High-dose zinc for a wound that is not zinc deficient offers no benefit and can cause copper deficiency anemia and neuropathy.
Trap 2: Full Feeding on Day 1 After Prolonged Starvation
Starting goal-rate tube feeds in a patient who has barely eaten for 2 weeks can trigger refeeding syndrome. Start low, give thiamine, and replace electrolytes.
A 70-kg woman with a stage 4 sacral pressure injury is at risk of malnutrition and has normal kidney and heart function. Using international pressure injury guideline targets, which daily energy and protein goals are most appropriate?
A malnourished 80-year-old man with a stage 3 pressure injury is eating only part of his meals. The team is choosing an oral nutritional supplement. Which option has the strongest evidence for improving pressure injury healing in this situation?
A 46-year-old man with alcohol use disorder has eaten almost nothing for 12 days and is admitted with an infected foot wound. His BMI is 16 kg/m², and his phosphate, potassium, and magnesium are at the low end of normal. The team plans to start tube feeding. What is the most appropriate approach?