The presentation describes the acute response of the body to stress, making nutritional assessment, nutritional therapy options and complications.

1. BY : DR RUHAMA YOSEPH
(MD)

2.  Introduction
 Metabolic response to stress
 Nutritional assessment
 Estimating macronutrient requirements
 Nutritional therapy
 Principles
 Options
 Special considerations
 Complications
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3.  Malnutrition contributes greatly to illness,
morality and cost of health care
 Incidence 30-55%
 Generally 3 types
 Marasmus: prolonged, non-stressed starvation
 Kwashiorkor-like (hypoalbuminemic): acute in
onset, stress resulting in visceral protein loss
 Marasmic-hypoalbuminemic: stress induced loss
of adaptive mechanisms
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4.  Indications for nutritional support:
 Preventing and treating malnutrition of patients
unable/unwilling to take oral feeding
 Will nutrition improve prognosis/quality of life?
 Can it be utilized by the stressed septic patient?
 During the acute phase of stressful illness, goal
is to provide energy substrates to aid cellular
functions
 Repletion of lost fat and muscle tissue must
wait until the anabolic phase of the illness.
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5. Catabolism
Anabolism
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Anabolism Catabolism

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DIET
Fatty acids Triglycerides
Glucose
Glycogen
Amino acids
Adipose
Tissue
Protein
Muscle
LIVER
Urea

7.  In depressed glucose intake glucose level in
blood maintained by 2 mechanisms:
1. Fatty acid used as alternative fuel
2. Activation of glucose producing pathways
 Glycogenolysis
Since glycogen store is limited this can’t last
>48 hrs
 Gluconeogenesis
Other carbon sources used to produce glucose
in liver & to lesser extent in kidneys
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8.  Substrates for gluconeogensis are:
 Lactate/ pyruvate (supplies 60-70% of the
carbon)
 Glycerol derived from triglycerides
 Amino acids from peripheral tissue and liver
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9.  Factors that decrease mitochondrial
oxidation, and thus increase lactate
production, increase gluconeogenesis
 Starvation, 90% inhibition of whole body glucose
oxidation
 In type I DM, 70% inhibition
 In Type II DM, 40% inhibition
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10.  Alanine is used as a substrate for
transamination reactions in the liver and
kidney
 In cases of protein breakdown, amino acids
act as substrates of gluconeogensis via
alanine
 That is why in malnutrition exogenous
glucose is essential to spare the loss of body
protein mass
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11.  In prolonged starvation, ketone bodies are
produced from incomplete oxidation of fatty
acids. This body’s adaptation mechanism.
 Some cells, such as cardiac, muscle and
kidney cells, adapt to use ketone bodies as
fuel
 As a result; muscle protein is spared and the
need for glucose is reduced
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12.  Allostasis mechanisms become insufficient to
maintain hemostasis
 Allostasis- achieving stability of internal environment
through physiological or behavioral changes
 There are three phases of response to stress:
1. Ebb phase (24 hrs)
2. Flow phase
3. Anabolic phase (months)
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13.  During ebb phase there would be
hypoperfusion, hypoxia, hypometabolism… and
resuscitative measures are important
 Flow- there is catabolism & hypermetabolism.
Duration depends on severity of injury
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EBB
FLOW

14.  During Anabolic phase, there is repair of
injury and return to normal metabolic
environment
 In “second hits” the changes will be
perpetuated
 Hypothalamus-pituitary axis is central
allostatic means to overcome the changes
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15.  Stress induces hormonal response via
stimulation of the hypothalamus by humoral
factors (TNF-α, Il-1) and limbic system
(emotional factors)
 Stimulated Hypothalamus:
 Activates sympathetic nervous system
 Adjusts body temperature
 Releases hormones to stimulate pituitary gland
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16. Hypothalamus
Sympathetic
nervous
system
Adrenal
medula
Catecholamine
↑
Pancreas
↑Glucagon
CVS
Pituitary
gland
ACTH
↑ cortisol
↑GH,
Prolactin,
ADH
Body
temperature
regulation
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17.  Glucocorticoid:
 secretion is normally by circadian rhythm,
by control of hypothalamus-pituitary axis
 In stressed state, secretion increases 2-3 fold
 Exogenous steroids; attenuate response by
negative feedback mechanism
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18.  Action of cortisol:
 Activate gluconeogenesis
 Sensitize adipose tissue for lipolytic hormones
 Increases proteolysis
 Insulin resistance development
 Anti-inflammatory and immunosuppressive
effects
 Duration of action depends on degree of
surgical trauma
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19.  Growth hormone:
 During stress has biphasic response
 Initial 2-3 hrs, insulin like effect
 Later, anti-insulin like & anabolic effect
 Amino acids used for protein synthesis
 Insulin resistance, glucose intolerance
 Lipolysis (by stimulation of catecholamines)
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20.  Glucagon and Insulin:
 During surgery glucagon: insulin ratio
increases. This is an effect of sympathetic NS
activation and release of catecholamines
 Post-operatively, insulin increases
 In sepsis, these mechanism fail and
hypoglycemia results
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21.  Weight
 Albumin
 During stress liver reprioritizes acute phase
proteins
 Prealbumin
 A carrier protein which remains low if stress is
not addressed
 Normal is 16mg/dl
 Determined once or twice weekly
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22. 1. Kcals per kilogram body weight according
to weight & activity classification
Ideal weight and activity level from a
general chart can be used to obtain
multiplication factors
2. BEE x activity factor x stress factor
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23.  BEE x AF x IF Method
 There are two main methods to ascertain
basal energy expenditure (BEE)
 indirect calorimetry and
 prediction equation, the gold standard of which
is the Harris Benedict Equation (HBE).
 Once BEE has been determined, that figure is
multiplied by an activity factor (AF), then an
injury factor (IF) to determine total energy
needs.
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24.  HBE (Harris Benedict Equation):
 Men:
BEE (kcal/d) = 66.5 + (13.8 x W) + (5.0 x H) - (6.8 x A)
 Women:
BEE (kcal/d) = 655.1 + (9.1 x W) + (1.8 x H) - (4.7 x A)
Where:
W = weight in kg
H = height in cm
A = age in years
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25. Activity Factor (AF) Injury Factor (IF)
Bedrest 1.2 Minor Surgery 1.2
Ambulatory 1.3 Major Surgery 1.1-1.2
Anabolic Factor Mild Infection 1.0-1.2
Mild weight loss 1.05 Mod. Infection 1.2-1.4
Mod- severe weight loss
1.1-
1.15
Severe Infection 1.4-1.8
Skeletal trauma 1.2-1.35
Blunt trauma 1.15-1.35
Head trauma 1.4
Head trauma* 1.6
</20% BSA burns 1.0-1.5
20-40% BSA burns 1.5-1.85
>40% BSA burns 1.85-1.95
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26.  Recommendations:
 Normal patient 25-30 Kcal/kg/day
 Under weight 35-40
 Obese patient 20-25
 Morbidly Obese patient 10-20
 Re-feeding syndrome 20
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27.  Gram/Kg method
 Nitrogen balance method
 NPC: N ratio
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28.  Gram/kg method:
The simplest, but least precise, method to
estimate protein needs is by multiplying IBW
in kilograms by a factor appropriate for the
patient's condition
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29.  Nitrogen balance method:
A nitrogen balance study is the comparison of
nitrogen being consumed (orally or via IV)
compared to the amount of nitrogen being
lost from the body.
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Nitrogen In Nitrogen Out
Food Urine
TPN Feces
Sweat
Skin

30.  Steps to calculate nitrogen balance:
1. Determine nitrogen lost in urine by a 24 hour
urinary urea nitrogen test.
2. Add 4* to the UUN to account for non-urinary
losses of nitrogen
3. Determine nitrogen intake by dividing the
daily protein intake by 6.25
4. N-bal.= value from #3 - value from #4
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31.  Negative nitrogen balance is an undesirable
state that occurs with weight loss, traumatic
injury and some stressful/illness conditions.
 The best nutrition support can deter muscle
loss by no more than 50%
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32.  The non-protein kcalorie to nitrogen ratio
(NPC:N) is calculated as follows:
1. Calculate grams of nitrogen supplied per
day (1 g N = 6.25g protein)
2. Divide total non-protein kcalories by grams
of nitrogen
 NPC:N
 80:1 the most severely stressed patients
 100:1 severely stressed patients
 150:1 unstressed patient
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33.  Early management is better than late
 Enteral is superior to parenteral
 The dose of EN
 Composition of EN
 Optimizing EN
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34.  Early management, that is not later than 48
hrs is associated with good outcomes
 However patients should be well resuscitated
and hemodynamically stable
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35.  EN is preferred to TPN
 It uses normal physiologic action of digestion
and absorption
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36.  Use of GI tract for feeding
 Benefits :
 Maintains gut integrity by preserving IgA production
 Prevent paralytic ileus
 Attenuate metabolic response to stress
 Decrease incidence of stress-induced bleeding
 Prevents infectious complications when started early
 Hemodynamic stability is a pre-requisite for
start of EN
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37.  Indications:
 Protein-energy malnutrition with inadequate
oral nutrient intake for 5 or more days
 Less than 50% of required nutrient intake
orally for 5-7 days
 Severe dysphagia
 Coma
 Low output enterocutaneous fistula
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38.  Contraindications:
 Intestinal obstruction, ileus, or hypomotility
of the intestine
 Severe diarrhea
 High output enterocutaneous fistulas
 Severe acute pancreatitis or shock
 When prognosis does not warrant aggressive
nutritional support
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39.  EN can be administered by
 NG tube
 Duodenal tube
 Jejunal feeding tube, for those at risk of
pulmonary aspiration
 Ostomy tube feeding- surgically created if
patients must be on TF for extended time
 Esophagostomy
 Gasrtostomy
 Jejunostomy
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40.  Types of Formulas:
 Intact
Polymeric formulas which contain unaltered
molecules of protein, fats, carbohydrates
 Hydrolyzed
Monomeric formulas, contain predigested
proteins and simple carbohydrates, plus a small
amount of oil or a blend of medium chain
triglycerides
 Modular
Incomplete liquid supplement that contains
specific nutrients, usually a single macronutrient
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41.  The presence of bowel sounds is unnecessary
for initiation of tube feeding
 Ways of administration:
 Continuous drip
 Intermittent
 cyclic
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42.  Continuous drip feeding
 With help of gravity or pump
 Better tolerated
 The initial rate should be slow
 Then, steady rate maintained
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43.  Intermittent bolus feeding
 Consist of 250 - 300 mL given over 20 min- 2hr
period, followed by 25-60 mL water
 At least 3 hours between each bolus feeding.
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44.  Cyclic feeding
 Usually as a supplement to an inadequate oral
diet
 Provided often by a pump over 8-12 hr/d
continuous drip
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45.  Monitoring:
 Gastric residual Volume should be ordered Q4hrs
for patients fed with NGT or gastrostomy tubes
 Elevated RV is an indication to withhold feeding
and look for the cause
 Tight glycemic control (glucose <110mg/dL)
 Electrolyte management
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46.  Measuring ‘Residuals’
 Before each bolus feeding, gastric contents
should be suctioned out and returned to the
stomach before a new feeding is administered to
ensure that minimal residue remains from the
previous feeding.
 GRV is used as marker of risk of aspiration
 Acceptable RV is 250-350 mL
 …
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47.  Simply changing patients position to right side
may reduce RV
 Patients should be positioned with the head
elevated 30 degrees before and after feeding
 Gastric stimulants can be given to improve
gastric motility
 Metclorpramide
 Erythromycin
 Naloxone
 Domperidone
 …
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48.  Prevention of bacterial contamination is
crucial
 Especially with blenderized formulas
 Administration of medicine
 Tube should be flushed before and after
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49.  Monitoring of tolerance
 Symptoms to look for include:
 Diarrhea, nausea, cramping, constipation, aspiration
 Hydration status can be monitored via daily
weights, Hct, BUN, and electrolytes.
 Hypoalbuminemia is commonly implicated in the
development of diarrhea among TF patients.
 less than 3.5g/dl then dilute the formula, if less than
2.5g/dl enteral feeding may not be tolerated at all.
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50.  Complications of tube feeding:
 Dumping syndrome and regurgitation
 Diarrhea and dehydration
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51.  Calculation of Kcaloric and Protein Needs
of TF Patients is essential
 Obligatory Fluid Output
The adequacy of fluid intake of patient can
be estimated with the UOP
It is the minimum output of urine necessary
to remove wastes and is estimated to be 700
ml per day or 30 ml per hour.
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52.  It is the use of a site outside the GI tract,
specifically, the circulatory system, for
feeding.
 The general rule for deciding whether to use
enteral or parenteral feeding is, "If the gut
works, use it".
 Administered peripherally or by a central
route
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53.  Indications:
• GI tract obstruction
• Ileus
• Severe malabsorption
• Persistent nausea & vomiting
• Unusable GIT for 5-7 days
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54.  Here peripheral vein is used
 Provide partial or complete nutrition
depending on solution osmolarity
 A hypertonic PN solution results in an
osmotic gradient that causes water to enter
the blood vessel
 vessels will become inflamed and
thrombosed…
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55.  Protein and carbohydrate both contribute to
hypertonicity.
 Fat is isotonic and can therefore be
administered peripherally.
 Up to 1800-2500 kcal and 90g protein can be
supplied for short time only
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56.  Recommended infusion rates for PPN
IBW(kg) Infusion rate (cc/hr)
40 60 - 80
50 75 -100
60 90 -120
70 100 -140
80 120 -160
90 130 -170
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57.  (Hyperalimentation)
 Large amounts of nutrients in a hypertonic
solution can be supplied via TPN.
 Catheter is surgically placed into the
superior vena cava
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58.  Amino acid solutions
 Are used for protein synthesis rather than
energy supplementation
 Protein is provided as a crystalline amino
acid solution.
 Solutions vary in amino acid concentration
and amino acid composition.
 Nonprotein kcalorie to nitrogen
ratio of 80:1 to 150:1 is used
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59.  Dextrose solutions:
 Dextrose in solution has 3.4 kcal/gm (rather
than 4 kcal/gm).
 Dextrose solutions come in different
concentrations, and the solution is
abbreviated D(%solution)W.
 For example, D50W indicates a 50% dextrose in water
solution.
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60.  The maximum oxidation rate of glucose
allows Dextrose solutions not be
administered above 0.36g per kg body
weight/hour.
 Excess glucose is converted to fat →fatty
liver.
 In addition the conversion results in excess
CO2 which is undesirable for patients with
respiratory problems.
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61.  Lipid emulsions:
 Lipids in parenteral nutrition are used as a
source of essential fatty acids and energy.
 Are composed of soybean and/or safflower
oil, glycerol, and egg phospholipids
 Omega-6 fatty acids
 Approximately 4% of total kcaloric intake
should be EFAs
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62.  Since IV lipids are isotonic and calorically
dense, they are a good source of kcalories
for hypermetabolic patients, or patients
with volume or carbohydrate restriction
 IV lipids come in bottles of 10% or 20%
emulsions.
 The 10% emulsion contains 1.1 kcal/ml the
20% emulsion contains 2 kcal/ml
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63.  To prevent hyperlipidemia, lipid emulsions
are not provided continuously.
 Typically, lipids are administered 2-3 times
per week, but can be provided daily.
 Infusion times of 4-6 hours for 10% lipids and
8-12 hours for 20% lipids are recommended
 Can be immunosuppressive and pro-
inflammatory in high concentrations
 In any event, a total of 2.5g/kg lipids per
day should not be exceeded.
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64.  Evaluation of patient’s lipid tolerance:
 Test dose
 Serum triglycerides
 Serum triglycerides shouldn’t exceed 250mg/day
 Plasma turbidity
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65.  Contraindications for using lipid emulstion
include:
 Abnormal lipid metabolism
 Lipid nephrosis
 Acute pancreatitis (if concomitant with or caused
by hyperlipidemia)
 Severe egg allergies
 Relative CI:
 A blood coagulation disorder
 Moderate to severe liver disease
 Compromised pulmonary function
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66.  Minerals and Electrolytes:
 Standard mineral and electrolyte mixtures
are available, and are designed to meet the
normal range of daily mineral/electrolyte
requirements.
 Individual electrolyte levels can be altered to
meet the needs of patients.
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67.  Trace Elements:
 Standard trace element mixtures are
available
 Iron can be given intramuscularly as needed.
When transferrin levels are low, free iron
increases and can increase susceptibility to
infections
 Copper supplementation must be
administered with caution to avoid toxicity.
 Extra zinc may be needed by some patients
to promote wound healing
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68.  Vitamins:
 Single vitamin supplements can be added to the
solution.
 Vitamin preparations should be added to the TPN
solution just prior to administration
 Water soluble vitamins are provided at levels
greater than the RDA since rapid administration
exceeds renal threshold
 Fat soluble vitamins can become toxic, and are
provided in amounts equal to the RDA.
 Vitamin K is not provided, must be given IV or
IM, at a dose of 2-4 mg/wk, depending on
prothrombin time
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69.  Other components:
 Albumin-Can be added if serum albumin
levels are very low.
 Heparin-An anticoagulant used to prevent
blood clots from forming on the IV catheter.
 Insulin-Used if needed to regulate blood
glucose levels.
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70. Complications:
 Infection
Can occur at the PN catheter insertion site
 Technical Complications
Pneumothorax & hemothorax that can result
if the chest wall is perforated with catheter
needle.
 Metabolic Complications…
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71.  Metabolic complications:
 Hypoglycemia
 Hyperglycemia
 Hypo/hypernatremia
 Hypo/hyperkalemia
 Hypo/hyperphosphatemia
 Hypo/hypermagnesimia
 Hypo/hypervitaminosis
 Essential Fatty Acid Defficiency
 Hyperchloremic metabolic acisosis
 Metabolic alkalosis
 Pre-renal azotemia
 Hepatic complications
 Respiratory complications
 Copper, zinc defieincy
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72.  Administration:
 Should start gradually
 Termination should also be gradual (2 hrs
period), otherwise rebound hypoglycemia
 It is good to continue TPN when the tube
feeding is started
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73.  Pre-operative TPN was seen to be effective only
for patients with curable upper GI cancer
 Post-operative one indicated for patients who
are not anticipated to be started on feeding
within 7-8 days
 For patients started on MV, starting of enteral
nutrition in first 24-48 hrs was found to have a
significant effect in patient outcome
 Patients who had pancreaticodeudenectomy
despite their nutritional status are not
candidates
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74.  Miller’s Aneshesia, 7th ed
 The McGraw-Hill companies . Manual of
Critical Care. International Ed, 2009
 Clinical Practice Guidelines for Nutrition
Support in Mechanically Ventilated, Critically
Ill Adult Patients1. Dr. Daren Heyland
 Kingston General Hospital
 Tube Feeding Tutorial. http://www.csun.edu.
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75. THANKYOU!
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