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Nutrition Therapy in Burn-Injured Patients. Robin Saucier, RD, CNSC 28 September 2010. Burn Incidence and Treatment. In U.S. annually: 1,000,000 burns receiving medical treatment 4,000 fire and burn deaths 75% occur at scene of incident or during transport
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Nutrition Therapy in Burn-Injured Patients Robin Saucier, RD, CNSC 28 September 2010
Burn Incidence and Treatment In U.S. annually: • 1,000,000 burns receiving medical treatment • 4,000 fire and burn deaths • 75% occur at scene of incident or during transport • 40,000 admissions to hospital • 25,000 to hospital with specialized burn center • 94.4% survival rate when admitted to a specialized burn center • UCH is only ABA-verified burn center in Colorado Source: American Burn Association National Burn Repository (2005 report)
Types of Burns • Fire/flame (42%) • Scald (31%) • Hot object contact (9%) • Electrical (4%) • can continue to burn for up to weeks after initial insult, organ failure without significant skin involvement • Chemical (3%) • Other – radiation, skin disease, or unspecified/unknown etiology (6%) Source: American Burn Association National Burn Repository (2010 report)
Other conditions & considerations • Stevens-Johnson syndrome • Necrotizing fasciitis • Inhalation injury
Pathophysiology of Burns Severity • %TBSA • Depth of skin injury • Superficial (1st degree) • Partial thickness (2nd degree) • Full-thickness (3rd/4th degree) – incl muscle • ≥3rd degree requires grafting
Biphasic Metabolic Response • Ebb Phase Decrease in: cardiac output, oxygen consumption, REE, body temp, tissue perfusion. • Flow Phase • Acute response: Increase in: acute-phase proteins, catecholamines, cortisol, glucagon, cytokines, O2 consumption, REE, temp, tissue perfusion. • Adaptive response: Decrease in hypermetabolic rate, potential for restoration of body protein/LBM – can last for 9-12 months post-burn. • Fluid resuscitation: LR (per Parkland formula: 4ml/kg/%TBSA over first 24h) – can gain 5-13L of fluid • Metabolic rate peaks around 7-10 days post-burn.
Importance of Nutrition Intervention in Burns Protein-energy malnutrition occurs rapidly in burns and causes: • Impaired wound healing • Muscle wasting • Immunocompetence for months after initial injury • Growth retardation in children
Factors in Assessment • Severity (%TBSA/depth) • Age • Sex • Ventilatory status • Inhalation injury • Concomitant injuries • Medications/IV drips • Co-morbidities/PMH • Pre-burn nutritional status
Nutrition Assessment: Calories • Use pre-burn or usual weight, if known (fluid resuscitation may alter admit weight; ICU body wts not accurate indicator of body cell mass). • Adjusted body weight is appropriate with obesity (>120% IBW) • Use actual body weight even if below 100% ideal
Calculating Energy Requirements • Harris-Benedict equation x 1.5-2.0 • Ireton-Jones equation: EEE(v) = 1784 - 11(A) + 5(W) + 244 (S) + 239 (T) + 804 (B) EEE(s) = 629 - 11 (A) + 25 (W) - 609 (O)EEE=kcal/day: s=spontaneously breathing, v=ventilator-dependent; A=age (yrs); W=body weight - (actual dry weight) (kg); S=sex (male=1, female=0); T = trauma, B= burn, O=obesity defined as BMI>27 (if present=1, absent=0).
Calculating Energy Requirements • 25-45 kcal/kg • Curreri equation (be careful, often overestimates): 16-59yo: (25 x weight) + (40 x %TBSA) • Carlson equation REE for non-vented pt = BMR (0.89142 + 0.01335 × TBSA) × m² × 24 × activity factor of 1.25
Calculating Energy Requirements: Caveats • Energy surge reaches its peak around 7-10 days post-burn • Milner et al found that predictive equations most accurate in first 30 days post-burn • Predictive equations may over-estimate with sedation, paralytics (paralytics may decrease EE as much as 30%). • Indirect calorimetry most accurate but limitations. Utility of NICO? • NICO KCAL UTILIZATION: • VCO2 X 5.54 X 1440 = KCAL/Day
Nutrition Assessment: Protein • Primary goal is healing, closure, LBM sparing: do not reduce protein to preserve renal function. • Significant protein loss via wound exudate despite nutrition support • Estimated 110g/d during first 10 days post-burn • Estimated protein needs (depending on TBSA): • 20-25% overall calories • Superficial: 1.5-2.0 g/kg/d • Partial thickness: 2.0-2.5g/kg/d • Full thickness 2.5-3.0g/kg/d • In some cases up to 4g/kg/d/d
Nitrogen Balance • Nitrogen balance = N2 intake – (total UUN + fecal N2 loss + wound loss) • ≤10% TBSA open wound: 0.02g N2/kg/day • 11-30% TBSA open wound: 0.05g N2/kg/day • ≥30% TBSA open wound: 0.12g N2/kg/day
Nutrition Assessment: Glutamine • Only if NOT enrolled in Re-ENERGIZE. • Defer to unit RD if unsure or patient may still be enrolled. • Recommended dosage: • 0.5g glutamine/kg/day • Dosage is in 10g increments, given as bolus via FT in water
Glutamine Study • Based on the following hypotheses: • Enteral glutamine administration in adult subjects with severe thermal burn injuries decreases: • In-hospital mortality • Morbidity and length of care • The cost of care • Inclusion Criteria • ≥20% TBSA • Deep 2nd and/or 3rd degree burns requiring grafting • Age + TBSA = 60-119
Glutamine Study • Exclusion Criteria • ≥48 hours from admission to ICU to time of consent (if transferred may be enrolled up to 96 hrs post-burn at site investigator’s discretion) • Patients >80 yrs or <18 yrs of age • Liver cirrhosis – Child’s class C liver disease • Pregnancy • Associated multiple fractures or severe head trauma • Absolute contraindication for EN (intestinal occlusion or perforation, abdominal injury) • Patients with injuries from high voltage electrical shock • Patients who are moribund • Patients with BMI <18 or >50 • Enrollment in another industry-sponsored ICU intervention study
Glutamine Study • Prescribed energy needs: • Indirect calorimetry • Measured energy expenditure x 1.0-1.3, OR • Ireton-Jones equation, OR • Basal energy expenditure using Harris-Benedict equation • If ≥50% TBSA, use BEE x 1.7-2.0 • If ≤50% TBSA, use BEE x 1.5-1.6 • Energy needs to be adjusted according to progression of wound healing.
Glutamine Study • Prescribed Protein Needs • If ≥50% TBSA, use 2.0-3.0g/kg/d • If ≤50% TBSA, use 1.5-2.0(+) g/kg/d • Protein needs to be adjusted according to progression of wound healing & other biochemical markers. • Glutamine not included in protein allocation.
Feeding Modalities • If <20% TBSA, can trial high kcal/prot diet with po supps, calorie count. 10-20% TBSA may still need enteral nutrition if po suboptimal. • If ≥20% TBSA or <90% IBW, EN indicated. Usually started within first 24h of admission. • TPN only indicated when EN fails, or in cases of abdominal compartment syndrome, significant pressor usage, etc.
Enteral Nutrition • Feeding tubes placed within 4 hours of admission, EN started as soon as placement confirmed • Osmolite 1.2/1.5 as standard formula • If +inhalation injury, SIRS/sepsis, ALI, ARDS: consider Oxepa (caution with large burns – high fat, vitamin A content) • If co-morbid conditions indicate (e.g., neuro trauma), can use Nutren 2.0 for lower carb, fluid content. • Pt may become hypernatremic, TF’s may be changed to diluted (1:1, 1:2 with H2O) • Prune juice often added as part of bowel regimen, especially with rectal tube. • Include kcal given from Prostat in total kcals estimated/received
Additional Supplementation • Daily MVI • 500mg Ascorbic Acid BID • 220mg Zinc (if not receiving IV trace elements) – length of tx unknown (10-14 days?) • ? 10,000 IU Vitamin A • Oxandrolone (anabolic steroid to decrease loss of LBM, promote wound healing, counteract lysis during hypermetabolic state) • IV Trace elements (copper, zinc, selenium) for >20% TBSA. Requires central access. • 14d course for 20-60% burn • 21d course for >60% burn
Monitoring: Clinical Course • Review: Residuals, abd exam, stool output (rectal tube), I/O’s, significant changes in insulin gtt rates • Surgical course: OR/grafting, wound healing (% open wound) – closure may not significantly decrease hypermetabolic response. • Indirect calorimetry as indicated (appropriate with large burns when pt not responding to current nutrition therapy)
Monitoring: Lab Values • Prealbumin & CRP checked Q Monday • Sodium – loop diuretics, wound losses, fluid overload, hypertension • Potassium – wound losses, diuretic therapy, renal failure • Calcium – wound losses, chronic immobility • Phosphorus – immobility, renal failure
Adjusting Needs • Needs max around 7-10 days post-burn • May consider adjusting needs weekly until burns covered • Predictive equations may not be reliable after 30 days post-burn • Adjust needs for % open area: • Decreases needs: grafting, re-epithelialization • Increases needs: wound infection, graft loss, donor sites
Long-term Follow-up • Cycling TF’s: Allow for improved appetite as po increases • 50-100% TF volume often delivered over 12-16h if pt can tolerate volume until po >50% est needs. • Calorie count • High calorie/high protein diet • Oral supplementation
References • Gottschlich MM, Mayes T. Burns. In: Merritt R ed. The Aspen Nutr Support Practice Manual. 2nd ed. 2005:296-300. Silver Spring, MD: ASPEN. • Chan MM, Chan MM. Nutritional therapy for burns in children and adults. Nutrition, March 2009 25(3): 261-9. • Carlson DE et al. Resting energy expenditure in patients with thermal injuries. Surg Gynecol Obstet. 174(4):270-6. • Milner EA et al. A longitudinal study of resting energy expenditure in thermally injured patients. J Trauma. 37(2):167-70. • Cresci G, Gottschlich MM, Mayes T, Mueller C. Trauma, Surgery, and Burns. In: Gottschlich MM ed. Nutr Support Core Curriculum: A Case-Based Approach – the Adult Patient. 2007:455-476. Silver Spring, MD: ASPEN. • Berger MM. Antioxidant micronutrients in major trauma and burns: evidence and practice. Nutr Clin Practice. 2006;21(5):438-446. • Berger MM et al. Reduction of nosocomial pneumonia after major burns by trace element supplementation: aggregation of two randomised trials. Crit Care. 2006; 10:R153.