Transcript NUTRIENTS AND ENERGY METABOLISM

Metabolic Response to
Starvation and Trauma:
Nutritional Requirements
Objectives
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Explain the differences between metabolic
responses to starvation and trauma
Explain the effect of trauma on metabolic rate and
substrate utilization
Determine calorie and protein requirements during
metabolic stress
Metabolic Response to Fasting
GLUCOSE UTILIZED (g/hora)
I
II
III
40
IV
V
Exogenous
Glycogen
Gluconeogenesis
30
20
10
LEGEND
I
II
III
FUEL FOR
BRAIN
GLUCOSE
GLUCOSE
GLUCOSE
IV
GLUCOSE,
KETONES
V
GLUCOSE,
KETONES
Ruderman NB. Annu Rev Med 1975;26:248
Fasting – Early Stage
Muscle
Alanine / Pyruvate
Brain
Glucose
Glutamine
Glycerol
Gluconeogenesis
Ketogenesis
Fat
AGL
Ketones
Liver
Ureagenesis
Ketones
Urea
NH3
Intestine
Kidney
Fasting – Late Stage
Muscle
Alanine / Pyruvate
Brain
Glucose
Glutamine
Glycerol
Gluconeogenesis
Ketogenesis
Fat
AGL
Ketones
Liver
Ureagenesis
Ketones
Urea
NH3
Intestine
Kidney
Metabolic Reaction to Starvation
Hormone
Source
Norepinephrine
Norepinephrine
Epinephrine
Thyroid Hormone T4
Sympathetic Nervous System
Adrenal Gland
Adrenal Gland
Thyroid Gland (changes to T3
peripherally)
Landberg L, et al. N Engl J Med 1978;298:1295.
Change in Secretion
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

Energy Expenditure in Starvation
Nitrogen Excretion (g/day)
12
Normal Range
8
Partial Starvation
4
Total Starvation
0
10
20
Days
Long CL et al. JPEN 1979;3:452-456
30
40
Metabolic Response to Trauma
Flow Phase
Energy Expenditure
Ebb Phase
Time
Cutherbertson DP, et al. Adv Clin Chem 1969;12:1-55
Metabolic Response to Trauma:
Ebb Phase
• Characterized by hypovolemic shock
• Priority is to maintain life/homeostasis
 Cardiac output
 Oxygen consumption
 Blood pressure
 Tissue perfusion
 Body temperature
 Metabolic rate
Cuthbertson DP, et al. Adv Clin Chem 1969;12:1-55
Welborn MB. In: Rombeau JL, Rolandelli RH, eds. Enteral and Tube Feeding. 3rd ed. 1997
Metabolic Response to Trauma:
Flow Phase
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 Catecholamines
 Glucocorticoids
 Glucagon
Release of cytokines, lipid mediators
Acute phase protein production
Cuthbertson DP, et al. Adv Clin Chem 1969;12:1-55
Welborn MB. In: Rombeau JL, Rolandelli RH, eds. Enteral and Tube Feeding. 3rd ed. 1997
Metabolic Response to Trauma
Endocrine
Response
Fatty Deposits
Fatty Acids
Liver & Muscle
(glycogen)
Glucose
Muscle
(amino acids)
Amino Acids
Metabolic Response to Trauma
Nitrogen Excretion (g/day)
28
24
20
16
12
8
4
0
10
Long CL, et al. JPEN 1979;3:452-456
20
Days
30
40
Severity of Trauma: Effects on Nitrogen
Losses and Metabolic Rate
Nitrogen Loss in Urine
Major
Cirugía
mayor
Surgery
Quemadura
Moderate
to Severe
moderadaBurn
a grave
Infección
Infection
Sepsis
Severe
grave
Sepsis
Cirugía
Elective
electiva
Surgery
Basal Metabolic Rate
Adapted from Long CL, et al. JPEN 1979;3:452-456
Metabolic Response
to Starvation and Trauma
Metabolic rate
Body fuels
Body protein
Urinary nitrogen
Weight loss
Starvation
Trauma or Disease
conserved
conserved
wasted
wasted
slow
rapid
The body adapts to starvation, but not in the
presence of critical injury or disease.
Popp MB, et al. In: Fischer JF, ed. Surgical Nutrition. 1983.
Metabolic Response to Surgical Trauma
Metabolic Changes after Trauma
Muscle
Alanine / Pyruvate
Brain
Glucose
Glutamine
Glycerol
Gluconeogenesis
Ketogenesis
Fat
AGL
Ketones
Liver
Ureagenesis
Ketones
Urea
NH3
Intestine
Kidney
Determining Calorie Requirements
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Indirect calorimetry
Harris-Benedict x stress factor x activity factor
25-30 kcal/kg body weight/day
Metabolic Response to Starvation and
Trauma: Nutritional Requirements
Injury
Minor surgery
Long bone fracture
Cancer
Peritonitis/sepsis
Severe infection/multiple trauma
Multi-organ failure syndrome
Burns
Activity
Confined to bed
Out of bed
Stress Factor
1.00 – 1.10
1.15 – 1.30
1.10 – 1.30
1.10 – 1.30
1.20 – 1.40
1.20 – 1.40
1.20 – 2.00
Example:
Energy requirements for
patient with cancer in bed
= BEE x 1.10 x 1.2
Activity Factor
1.2
1.3
ADA: Manual Of Clinical Dietetics. 5th ed. Chicago: American Dietetic Association; 1996
Long CL, et al. JPEN 1979;3:452-456
Metabolic Response to Overfeeding
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Hyperglycemia
Hypertriglyceridemia
Hypercapnia
Fatty liver
Hypophosphatemia, hypomagnesemia, hypokalemia
Barton RG. Nutr Clin Pract 1994;9:127-139
Macronutrients during Stress
Carbohydrate
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At least 100 g/day needed to prevent ketosis
Carbohydrate intake during stress should be between
30%-40% of total calories
Glucose intake should not exceed
5 mg/kg/min
Barton RG. Nutr Clin Pract 1994;9:127-139
ASPEN Board of Directors. JPEN 2002; 26 Suppl 1:22SA
Macronutrientes during Stress
Fat
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Provide 20%-35% of total calories
Maximum recommendation for intravenous lipid infusion:
1.0 -1.5 g/kg/day
Monitor triglyceride level to ensure adequate lipid
clearance
Barton RG. Nutr Clin Pract 1994;9:127-139
ASPEN Board of Directors. JPEN 2002;26 Suppl 1:22SA
Macronutrients during Stress
Protein
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Requirements range from 1.2-2.0 g/kg/day during stress
Comprise 20%-30% of total calories during stress
Barton RG. Nutr Clin Pract 1994;9:127-139
ASPEN Board of Directors. JPEN 2002;26 Suppl 1:22SA
Determining Protein Requirements for
Hospitalized Patients
No Stress
Moderate Stress
Severe Stress
Calorie:Nitrogen Ratio
> 150:1
150-100:1
< 100:1
Percent Potein / Total
Calories
< 15%
protein
15-20%
protein
Protein / kg Body Weight
0.8
g/kg/day
1.0-1.2 g/kg/day
Stress Level
> 20%
protein
1.5-2.0
g/kg/day
Role of Glutamine in Metabolic Stress
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Considered “conditionally essential” for critical patients
Depleted after trauma
Provides fuel for the cells of the immune system and GI
tract
Helps maintain or restore intestinal mucosal integrity
Smith RJ, et al. JPEN 1990;14(4 Suppl):94S-99S; Pastores SM, et al. Nutrition 1994;10:385-391
Calder PC. Clin Nutr 1994;13:2-8; Furst P. Eur J Clin Nutr 1994;48:607-616
Standen J, Bihari D. Curr Opin Clin Nutr Metab Care 2000;3:149-157
Role of Arginine in Metabolic Stress
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Provides substrates to immune system
Increases nitrogen retention after metabolic stress
Improves wound healing in animal models
Stimulates secretion of growth hormone and is a precursor
for polyamines and nitric oxide
Not appropriate for septic or inflammatory patients.
“Giving arginine to a septic patient is like putting gasoline on an already burning fire. ”
- B. Mizock, Medical Intensive Care Unit, Cook County Hospital, Chicago, IL
Barbul A. JPEN 1986;10:227-238; Barbul A, et al. J Surg Res 1980;29:228-235
Key Vitamins and Minerals
Vitamin A
Vitamin C
B Vitamins
Pyridoxine
Zinc
Vitamin E
Folic Acid,
Iron, B12
Wound healing and tissue repair
Collagen synthesis, wound healing
Metabolism, carbohydrate utilization
Essential for protein synthesis
Wound healing, immune function, protein
synthesis
Antioxidant
Required for synthesis and replacement of red
blood cells
Summary
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Metabolic response to starvation is an adaptive
mechanism
Nutritional requirements increase during trauma