Nutrition & Burns - University of Colorado Denver

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Transcript Nutrition & Burns - University of Colorado Denver

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
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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
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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:
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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
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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=ventilatordependent; 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
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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
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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):
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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
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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
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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
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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
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(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
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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
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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 1216h if pt can tolerate volume until po >50%
est needs.
• Calorie count
• High calorie/high protein diet
• Oral supplementation
Why we do it
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.
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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.