2. M E D I C A L N U T R I T I O N
The use of oral nutritional
supplements, EN and PN.
under the supervision of
health practitioners for the
nutritional management of a
condition or disease
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4. CRITICALLY I LL
• One who has an illness or injury impairing
one or more vital organ systems such that
there is a high probability of imminent or life-
threatening deterioration in the patient's
condition”
• Most critically ill patients are unable to
provide their own nutrition. In these patients,
artificial nutrition is often provided.
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5. • Nutrition support refers to the provision of
either EN provided by an enteral access
device and/or PN provided intravenously.
• Critically ill patients may also receive IV fluid
intake or sedative medications, some of
which provide energy
CRITICALLY I LL
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12. QUALITY
• Isocaloric nutrition is the administration of
energy within 70: 110 % of the defined target
• Hypocaloric <70% of the defined target
• Trophic feeding 30-40% of target
• Overfeeding >110% of the defined targe
• A low protein treatment of CKD or AKI/AKD is
0.7 g/kg/d of protein.
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13. TROPHIC FEEDING
is a minimal administration of nutrients via GIT having beneficial effects
e.g.,
• Preserving intestinal epithelium
• Stimulating secretion of brush border enzymes
• Enhancing immune function
• Preserving epithelial tight cell junctions
• Preventing bacterial translocation
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15. NUTRITIONAL
INITIATION
Medical nutrition therapy shall be considered for all patients
staying in the ICU, mainly for more than 48 h
A general clinical assessment should be performed to
assess malnutrition in the ICU, until a specific tool has been
validated.
Among all the screening tools, only the NRS 2002 and the
Nutrition Risk in the Critically ill (NUTRIC) have been
extensively studied
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16. Crit Care. 2011;15(6):R268.
NRS ≥3 indicated severe risk of
malnutrition.
NRS = 0 indicated absence of
malnutrition.
NUTRIC SCORE
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22. LABORATORY TOOLS
• Inflammation ↥ C-reactive protein (CRP) +
hypoalbuminemia.
• Albumin and isolated pre-albumin (not good
nutritional markers), low values being a response to
inflammation (negative acute phase proteins)
• Albumin is a marker of severity of the condition and
reflects the inflammatory status
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25. ORAL OR
ENTERAL
• Oral diet shall be preferred over EN or PN in
critically ill patients who can eat.
• If oral intake is not possible, early EN (within
48 h) in critically ill adult patients should be
performed/initiated rather than delaying EN
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26. ENTERAL N.
• Continuous rather than bolus EN should be
used.
• Gastric access should be used as the
standard approach to initiate EN.
• In patients with gastric feeding intolerance not
solved with prokinetic agents, and at high risk
for aspiration post pyloric feeding should be
used.
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27. PROKINETIC
S
• Iv erythromycin should be used as
a first line.
• Alternatively, iv metoclopramide or
metoclopramide + erythromycin can
be used.
• Effectiveness of prokinetics is ↓ to
one third after 72 h and should be
discontinued after three days.
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28. PROKINETIC
S
Monitoring of established EN with
continued
measurements of GRV may not be
necessary; however, EN should be
delayed when GRV is >500 mL/6 h.
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32. PARENTERA
L N.
• Early and progressive PN can be provided
instead of no nutrition in case of
contraindications for EN in severely
malnourished patients.
• In case of contraindications to oral and EN, PN
should be implemented within 3-7 days
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33. PARENTERA
L N.
•Inability to maintain nutritional status due to severe
diarrhea or vomiting
•Small bowel obstruction
•Hypercatabolic states due to sepsis, polytrauma, and
major fractures
•An anticipated period of nothing by mouth (NPO) > 7
days as in patients with inflammatory bowel disease
exacerbations as well as critically ill patients
Total Parenteral Nutrition - StatPearls - NCBI Bookshelf (nih.gov)
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34. PARENTERA
L N.
•Chronic intestinal obstruction as in intestinal cancer
•Bowel pseudo-obstruction with food intolerance.
•To rest the bowel in cases of GI fistulas with high flow
•Infant’s gastrointestinal system is immature or has a
congenital gastrointestinal malformation
•Post-operative bowel anastomosis leak
Total Parenteral Nutrition - StatPearls - NCBI Bookshelf (nih.gov)
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39. ENERGY
REQUIREMENT
In critically ill mechanically
ventilated patients, EE
should be determined by
using indirect calorimetry.
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40. INDIRECT CALORIMETRY
The method by which metabolic rate and substrate utilization are estimated in
human beings starting from respiratory gas exchange measurements and urinary
nitrogen excretion.
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41. START LOW
• If used indirect calorimetry ; hypocaloric nutrition
should be administered in the early phase of acute
illness. After day 3, caloric delivery can be ↑ up to
80-100% of measured EE.
• If used predictive equations hypocaloric nutrition
(< 70%) preferred over isocaloric nutrition for the
first week of ICU stay.
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42. In patients who do not tolerate full
dose EN After all strategies to
maximize EN tolerance have been
attempted
Add PN after 7-10 days if they are
unable to meet >60% of energy and
protein requirements by the EN.
TRY EN THEN ADD
PN
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43. CHARBS
RATE
The amount of glucose
(PN) or carbohydrates
(EN) administered to ICU
patients should not
exceed 5 mg/kg/min.
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44. • Hyperglycemia
• Enhanced CO2 production
• Enhanced lipogenesis
• Increased insulin requirements and no
advantage in protein sparing in comparison with
a lipid-based energy provision
EXCESS
CHARBS
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45. LIPIDS
• The administration of intravenous lipid
emulsions should be generally, a part of PN.
• Intravenous lipid (including non-nutritional
lipid sources) should not exceed 1.5 g
lipids/kg/day and should be adapted to
individual tolerance.
• Propofol is s a source of FA. This lipid
solution contains 1.1 kcal/mL and can
provide a large calorie load over and above
nutritional support
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46. I V LIPIDS COMPOSITION
• lipid emulsions : should include medium chain triglycerides, n-9
monounsaturated FAs, and n-3 polyunsaturated FAs.
• Smoflipid is a lipid emulsion for intravenous infusion that
contains a mixture of soybean oil, medium-chain triglycerides
(MCTs), olive oil, and fish oil
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47. GLUCOSE/ LIPID RATIO
The Goal : improving nitrogen
balance with a high ratio suggested.
Administration of marked amounts of
lipids can lead to liver function test
abnormalities
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48. GLUCOSE/ LIPID RATIO
Excess unsaturated fat Impaired
lung function and immune
suppression.
Close monitoring of triglycerides and
liver function tests may guide the
clinician for the best ratio.
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49. B U I L D I N G
H E A L I N G
I M M U N I T Y
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50. T H E C ATA B O L I C R E S P O N S E
Preiser et al. Critical Care (2021) 25:424
marked muscle mass loss of up to 1
kg per day over the first 10 days of
ICU stay and is associated with ICU-
Acquired Weakness .
Nitrogen losses increase fourfold
within the first 24 h of ICU stay .
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51. PROTEINS
Physical activity may improve the beneficial effects of
nutritional therapy.
During critical illness, 1.3 g/kg protein equivalents per
day can be delivered progressively.
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52. HIGH PROTEIN INTAKE
Preiser et al. Critical Care (2021) 25:424
A high-ptn. intake
(1.8g/kg/day)
should always be
accompanied by daily
monitoring of
plasma urea and
creatinine together
with base excess
If plasma urea ↑
monitor urea
excretion in urine and
may ↓ protein intake
and eventually renal
replacement therapy.
If base excess ↑ ↓
protein intake (with
other causes are
excluded).
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53. GLUTAMINE
It transports nitrogen between cells and/or organs and serves as
a metabolic fuel in rapidly proliferating cells.
Under physiological conditions, sufficient endogenous GLN
stores are maintained by both daily nutritional intake (80 g of
mixed protein contains approximately 10 g GLN)
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54. In critically ill trauma, additional EN doses of GLN (0.2-0.3 g/ kg/d)
can be administered for the first five days with EN.
In case of complicated wound healing, it can be administered for a
longer period of ten to 15 days.
In ICU patients except burn and trauma patients, additional enteral
GLN should not be administered.
In unstable and complex ICU patients, suffering from liver and renal
failure, parenteral GLN –dipeptide shall not be administered.
GLUTAMINE
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55. OMEGA 3
• Omega-3-enriched EN within nutritional doses can be
administered.
• Parenteral lipid emulsions enriched with Fish oil dose 0.1-
0.2 g/kg/d can be provided in patients receiving PN.
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56. E L E C T R O L Y T E S
R E C O M M E N D A T I
O N / L O F T P N
Sodium: 100 to 150 mEq
Magnesium: 8 to 24 mEq
Calcium: 10 to 20 mEq
Potassium: 50 to 100 mEq
Phosphorus: 15 to 30 mEq
Total Parenteral Nutrition - StatPearls - NCBI Bookshelf (nih.gov)
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57. Trace elements and vitamins
essential for the metabolism of carbohydrates, proteins and lipids
for immunity
antioxidant defense
for endocrine function,
for DNA synthesis, gene repair and cell signaling.
MICRONUTRIENTS
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58. MICRONUTRIENTS
Preiser et al. Critical Care (2021) 25:424
They work as a web, and 24 of them are "essential," meaning that
nutrition is the only source.
The body stores of MNs are variable but generally insufficient to
ensure normal metabolism beyond one week.
The MNs needs will depend on the presence of prior deficiency,
food intake before admission, particular body fluid losses, disease,
and feeding rate.
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59. • During the early phase, as EN cannot cover the everyday needs and
the higher needs associated with critical illness, early intravenous
delivery of doses like those used in PN is rational (1 vial multitrace
element and multivitamin+100–200 mg thiamine)
Preiser et al. Critical Care (2021) 25:424
MICRONUTRIENTS
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60. A N T I O X I D A N T S
• Oxidative stress :an imbalance between increased reactive oxygen and
nitrogen species and endogenous antioxidant mechanisms oxidative
damage to proteins and lipids .
• Seen in severe critical care conditions requiring mechanical ventilation, e.g.,
septic shock, severe pancreatitis, ARDS, major burns and trauma
Copper, Selenium, Zinc, and vitamins E and C
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61. A N T I O X I D A N T S
• Their levels are decreased in conditions of intense inflammation.
• Low serum Se is associated with intense inflammation, organ failures and
poor outcome in children and adults
• Antioxidants as high dose monotherapy should not be administered without
proven deficiency.
• ASPEN 2016 - recommend the provision of a combination of antioxidant
micronutrients “in safe doses” (i.e. 5-10 times Dietary reference intakes
DRI)
Copper, Selenium, Zinc, and vitamins E and C
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62. A S C O R B I C A C I D
• Enhance response to vasopressors
• Inhibits inflammatory microcirculation microthrombi formation
• Augments antibacterial defenses
Copper, Selenium, Zinc, and vitamins E and C
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The A.S.P.E.N./society of critical care medicine guidelines suggest using either NRS 2002 or NUTRIC/m NUTRIC for nutritional screening in critically ill patients.
The NUTRIC score is more useful in critically ill patients as it was developed in critically ill patients and recent food intake and weight change which is difficult to obtain in ICU patients were not included.
This evaluation is weak as has been stated:
‘carbohydrate could be theoretically eliminated from the diet, but it
is probably safe(r) to give 150 g/day: This may be explained by
organ preference on glucose such as the brain (100e120 g/day), red
blood cells, immune cells, renal medulla and all the transparent
tissues of the eyes
This evaluation is weak as has been stated:
‘carbohydrate could be theoretically eliminated from the diet, but it
is probably safe(r) to give 150 g/day: This may be explained by
organ preference on glucose such as the brain (100e120 g/day), red
blood cells, immune cells, renal medulla and all the transparent
tissues of the eyes