What is the recommended caloric intake for a burn patient?

Caloric Intake for Burn Patients

For adult burn patients, use the Toronto formula to calculate energy requirements, or provide 25-30 kcal/kg/day during the recovery phase, with 1.5-2 g/kg/day of protein. 1

Energy Requirements by Phase

Acute Phase (First Days to Weeks)

• Limit energy provision to 20-25 kcal/kg/day during the acute and initial phase of critical illness, as excess calories may be associated with less favorable outcomes 2
• For burns exceeding 30% TBSA, energy expenditure consistently reaches approximately 2X the predicted resting metabolic rate (RMR) 3
• Resting metabolic rate can reach up to 180% of basal rate in the first week following thermal injury 1

Recovery/Anabolic Phase

• Advance to 25-30 kcal/kg/day during the anabolic recovery phase 2
• The metabolic rate remains elevated to 130-150% at the time of full healing, 120-140% at 6 months, and 110-120% at 12 months per the Harris-Benedict equation 1

Calculation Methods

Preferred Approach: Toronto Formula

• The Toronto formula is the most accurate proxy for energy expenditure in adult burn patients when indirect calorimetry is unavailable 1
• Serial indirect calorimetry is regarded as the best option to fully meet evolving energy targets, as metabolic needs change throughout recovery 1

Pediatric Patients

• Use the Schofield formula for children 1
• Children require proportionally higher caloric intake due to higher surface area-to-weight ratio 4

Protein Requirements

• Provide 1.5-2 g/kg/day of protein for adults 1, 2
• Provide up to 3 g/kg/day of protein for children 1
• Burn patients oxidize amino acids at a rate 50% higher than baseline due to profound protein catabolism 1, 2
• Protein rates exceeding 2 g/kg/day have not demonstrated additional benefits 1

Macronutrient Composition

Carbohydrates

• Glucose oxidation increases from 4-5 to 7 g/kg/day after thermal injury 1, 2
• Avoid excess carbohydrate provision as it propagates hyperglycemia with subsequent exacerbation of inflammation, muscle breakdown, and excess fat production 1, 2
• Nearly all burn patients exhibit some degree of insulin resistance 1

Fats

• Use high-carbohydrate and low-fat formulas 2
• Low-fat diets help avoid exaggerated immunosuppression 1
• Evidence for omega-3 fatty acid supplementation remains inconclusive, with a recent systematic review unable to demonstrate benefit 1

Timing and Route

• Initiate enteral nutrition within 12-24 hours after burn injury 1, 2
• Early enteral nutrition (within 6-12 hours) attenuates the neuro-hormonal stress response and hypermetabolic response 1
• The oral or enteral routes are strongly preferred over parenteral nutrition 1, 2

Supplementation

• Add glutamine (or alpha-ketoglutarate) supplementation, which is associated with reduced gram-negative bacteremia, shorter hospital length of stay, and decreased mortality 1, 2
• Supplement copper, selenium, and zinc in higher-than-standard doses 2
• Provide micronutrient supplementation early in both adults and children 1

Clinical Outcomes

Adequate Nutrition (≥30 kcal/kg/24h)

• Mortality of 5.3% in patients receiving ≥30 kcal/kg/24h 5
• Reduced complication rates and shorter hospital stays 5

Inadequate Nutrition (<30 kcal/kg/24h)

• Mortality of 32.6% in patients receiving <30 kcal/kg/24h 5
• Pneumonia frequency increased by 2.0 times 5
• Sepsis frequency increased by 1.8 times 5
• Treatment duration 12.6 days longer 5

Common Pitfalls

• Do not use weight-based formulas alone without considering burn size and phase of recovery, as they fail to account for the profound hypermetabolism specific to thermal injury 1
• Avoid overfeeding during the acute phase, which can worsen outcomes and increase complications 2
• Monitor glucose closely given the profound insulin resistance and increased glucose oxidation in burn patients 1, 2
• Adjust nutrition therapy continuously based on disease progression and gut tolerance, as no single fixed amount applies throughout recovery 2