NUTRITIONAL SUPPORT IN ICU PATIENT ENTRAL AND PARENTRAL

2. Khalid Shawkey
Internist
ICU Unit
Internal Medicine department
Zagazig University

5. Body weight
• Maintained at a set point by balance between energy
intake and total energy expenditure
• Weight gain
- Increase in energy intake
- Decrease in energy expenditure (hypothyroidism)
- Fluid retention (heart failure or ascites)
• Weight loss
- Decrease energy intake due to loss of appetite ( cancer
and chronic diseases)
- Increase in energy requirement (sepsis and severe
trauma)

6. Why are so many hospital patients
malnourished?
1 Increased nutritional requirements (eg sepsis, burns,
surgery)
2 Increased nutritional losses (eg malabsorption, output from
stoma)
3 Decreased intake (eg dysphagia, nausea, sedation, coma)
4 Eff ect of treatment (eg nausea, diarrhoea)
5 Enforced starvation (eg prolonged periods nil by mouth)
6 Missing meals through being whisked off , eg for
investigations
7 Difficulty with feeding (eg lost dentures; no one available to
assist)
8 Unappetizing food

7. Screening of nutritional status
• To all patients on admission to hospital and
during their hospital stay
History:
- Recent weight loss
- recent reduced intake
- diet change
- nausea, vomiting, pain , diarrhoea which
might have led to reduced intake.

8. Examination:
- State of hydration : dehydration can go hand-in-hand
with malnutrition, and overhydration can mask
malnutrition.
- Evidence of malnutrition: skin hanging off muscles (eg
over biceps); no fat between fold of skin; hair rough
and wiry; pressure sores; sores at corner of mouth.
- Calculate body mass index :BMI <20kg/m2 suggests
malnour ishment.
- Anthropomorphic indices, eg mid arm circumference,
skin fold measures and grip strength are also used.

9. Investigations:
• plasma proteins: albumin, pre-albumin
(shorter half life than albumin),
transferrinƒ(decrease may indicate decreased
nutritional status or disease state)
• thyroid-binding globulin, retinol-binding
protein (may be too sensitive)

10. Who need nutritional support
Patient malnourished or at risk of
malnutrition
• Malnutrition
- BMI<18.5 kg/m2
- Unintentional weight loss >1% within the last
3-6 months
- BMI<20 kg /m2 and unintentional weight loss
>5%within the last 3-6 months

11. • At risk of malnutrition
- Eaten little or nothing for >5 days or likely to
eat little or nothing for the next 5 days or
longer
- Poor absorptive capacity or high nutrient
losses (malabsorption , fistula , short bowel
syndrome ) or increased nutritional needs (
burn , trauma and sepsis)

13. Benefits of Nutritional Support
• Preservation of nutritional status
• Prevention of complications of protein
malnutrition
•  Post-operative complications

14. Entral nutrition
• Cheaper
• More physiological (nutrients in the intestinal
lumen prevent atrophy of the gut and
pancreas)
• prevents gallstones by stimulating gallbladder
motility
• Fewer complications
• Should be used if the gastrointestinal tract is
functioning normally

15. Relative Contraindications
• non-functioning gut (e.g. intestinal
obstruction, enteroenteral or enterocutaneous
fistulae)
• uncontrolled diarrhea
• GI bleeding

16. Enteral versus Parenteral Nutrition for
Acute
Pancreatitis
• Cochrane DB of Syst Rev 2010;1:CD002837
• Purpose: Compare EN versus TPN on mortality, morbidity
and hospital stay in patients with pancreatitis.
• Study Selection: RCTs of TPN versus EN in pancreatitis.
• Results: Eight trials (n=348) were included.Enteral nutrition
decreases RR of death (0.50), multiple organ failure (0.55),
infection (0.39) and other local complications (0.70). It also
decreased hospital stay by 2.37 d.
• Conclusion: EN reduces mortality, organ failure, infections
and length of hospital stay in patients with pancreatitis.

17. Routes of entral nutrition
• Per mouth
• Naso gastric tube for short term enteral
nutrition
• nasojejunal (NJ) tube
• Percutanous endoscopic gastrostomy(PEG) for
patients who need feeding for longer than 2
weeks
• Percutanous jejunostomy

23. ENTERAL NUTRITION FORMULAS
• Polymeric feeds consist of whole protein, carbohydrate, fat as
a liquid, with or without fibre (eg Osmolite, Isocal, Ensure,
Jevity ). Normally contain ~1kCal/mL and 4–6g protein per
100mL. Most people’s requirements are met with 2L/24h.
• Elemental feeds consist of protein as amino acids,
carbohydrate as simple sugars, fat content low (therefore high
osmolarity) (e.g. Vivonex)
• Also disease-specifi c feeds, eg in liver cirrhosis with hepatic
encephalopathy branched-chain amino acid-enriched
formulae, High energy low electrolyte diet for dialysis
patients and low carbohydrate high fat solutions for ventilated
patients.

25. standard enteral formula
• Tolerated by the majority of patients.
• Composition: polymeric/whole protein,
maltodextrins, vegetable fat, electrolytes and
micronutrients.
• Nutrison: 1 kcal/ml & 4g protein/100ml.
• Energy: 1.5 kcal/ml & 6g protein/100ml.
• Protein Plus: 1.25 kcal/ml & 6.3g protein/100ml

26. Guidelines for success
• Use fine-bore (9 Fr) nasogastric feeding tube when possible.
• Elevation of the head of the bed
• Check position of nasogastric tube (pH testing) or
nasoduodenal tube (X-ray) before starting feeding.
• continuous gastric infusion is initiated using a half-strength
diet at a rate of 25-50 mL/h. This can be advanced to full
strength as tolerated to meet the energy target.
• Weigh weekly, check blood glucose and plasma electrolytes
(including phosphate, zinc, and magnesium, if previously
malnourished).
• Treat underlying conditions vigorously, eg sepsis may
impede +ve nitrogen balance.
• Close liaison with a dietician is essential.

27. Complications of entral feeding
Gastrointestinal
• Distension
• Nausea and vomiting
• Diarrhoea
• Constipation
• Intestinal ischaemia

28. Infectious
• Aspiration pneumonia
• Bacterial contamination
Mechanical
• Malposition of feeding tube
• Sinusitis
• Ulcerations / erosions
• Blockage of tubes

29. Parenteral nutrition
the practice of feeding a person intravenously,
by passing the usual process of eating and
digestion

30. Indications
• short term (<1 mo)
- ƒwhenever GI tract not functioning
- ƒonly situations where PN has been well shown to
increase survival are after bone marrow transplant
and in short bowel syndrome, some evidence for
benefit in gastric cancer, but often used in ICU,
perioperatively and difficult to control sepsis
- preoperative: only useful in severely malnourished
(e.g. loss of >15% of pre-morbid weight, serum
albumin <28 g/L or <2.8 g/dL), and only if given for ≥2
wk

31. - ƒrenal failure: PN shown to increase rate of recovery; no
increase in survival
- ƒliver disease: branched chain amino acids may shorten
duration of encephalopathy; no increase in survival
- IBD: PN closes fistulae and heals acute exacerbations of
mucosal inflammation, but effect is transient (EN is equally
effective)
- some evidence for efficacy, but convincing data not available
for:
Š.radiation/chemotherapy-induced enteritis
Š.AIDS with wasting diarrhea
Š.severe acute pancreatitis

32. • long term (>1 mo): can be given at home
- severe untreatable small bowel disease (e.g.
radiation enteritis, extensive CD, high output
fistulae)
- following surgical resection of >70% of bowel
(e.g. bowel infarction)
- severe motility diseases (e.g. scleroderma
affecting bowel)

33. Relative Contraindications
• functional GI tract for enteral nutrition
• active infection; at least until appropriate
antibiotic coverage
• inadequate venous access; triple-lumen
central venous lines usually prevent this
problem
• unreliable patient or clinical setting

34. Two primary types of PN
• Central parenteral nutrition (CPN) and
• Peripheral parenteral nutrition (PPN).

35. Central parenteral nutrition or total
parenteral nutrition (TPN)
• provides nutrients through a large-diameter vein, usually
the superior vena cava by access of the subclavian or
internal jugular vein.
• With CPN a hyperosmolar formula (1300 to 1800 mOsm/L)
can be provided consisting of glucose (15% to 25% final
concentration), amino acids, and electrolytes to fully meet
the nutrient needs of the patient.
• Central parenteral nutrition can be maintained for
prolonged periods and can be adjusted to meet nutrient
and volume needs for patients who may require a fluid
restriction (1). When venous access for the delivery of
nutrients is required for greater than 2 weeks, CPN is
indicated (2).
1. Mirtallo JM. Introduction to parenteral nutrition. In: Gottschlich MM, ed. The Science and Practice of Nutrition
Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001.
2. ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral
nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA.

37. Peripheral parenteral nutrition
• uses the peripheral vein as venous access. This form of parenteral nutrition is
similar to CPN except lower formula concentrations have to be provided due to
use of the peripheral vein that can only tolerate solutions providing less than 900
mOsm/L.
• Compared with CPN formulas, PPN formulas have a lower dextrose concentration
(5% to 10% final) and amino acid (3% final) concentrations.
• Because of the inability to infuse higher concentrations via the peripheral vein,
larger fluid volumes often have to be administered in PPN to provide comparable
energy and protein doses seen with CPN. This poses a challenge for patients
requiring fluid restriction.
• The maximum volume of PPN usually tolerated is 3 L/day (125 mL/hour).
Repletion of nutrient stores is not a goal of PPN, and it is not intended to be used
in severely malnourished patients (1).
• PPNis indicated only for mildly to moderately malnourished patients when they
are unable to ingest adequate energy orally or enterally, or when CPN is not
feasible. Typically, PPN is used for short periods (up to 2 weeks) because of limited
tolerance and vulnerability of peripheral veins (eg, risk of peripheral venous
thrombophlebitis) (1).
1. ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the
use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26
(suppl)(1):1SA-138SA.

38. Requirements
• The components of parenteral nutrition include
adequate fluid (30 mL/kg body weight/24 h for
adults, plus any abnormal loss);
• energy from glucose, amino acids, and lipid
solutions;
• nutrients essential in severely ill pts, such as
glutamine, nucleotides, and products of
methionine metabolism; and electrolytes,
vitamins, and minerals.

39. Caloric Requirements
Schofield Equation
25 to 30 kcal/kg/day
How Much CHO & Fats?
4-7 mg/kg/min/24h (Espen 2009) of glucose
Contain 4 kcal /g
CHO usually form 60-70 % of calories
0.7-1.5 g / kg Lipid(Espen 2006)
Contain 9 kcal/g
Fats usually form 30 to 40% of calories

40. How Much Protein to Give?
Non-stress patients 0.8 g / kg / day
Mild stress 1.0 to 1.2 g / kg / day
Moderate stress 1.3 to 1.75 g / kg / day
Severe stress 2 to 2.5 g / kg / day
Contain 4 kcal/g
15-20% of total calories

41. Electrolyte Requirements
Cater for maintenance + replacement needs
Na+ 1 to 2 mmol/kg/d (or 60-120 meq/d)
K+ 0.5 to 1 mmol/kg/d (or 30 - 60 meq/d)
Mg++ 0.35 to 0.45 meq/kg/d (or 10 to 20 meq /d)
Ca++ 0.2 to 0.3 meq/kg/d (or 10 to 15 meq/d)
PO4
2- 20 to 30 mmol/d

42. Trace Elements
Zn 2-4 mg/day
Cr 10-15 ug/day
Cu 0.3 to 0.5 mg/day
Mn 0.4 to 0.8 mg/day

43. DISEASE SPECIFIC FORMULATIONS
• Renal failure
eg. kidmin
- High energy feeds is used (2kcal/ml) to reduce
volume
- In TPN essential amino acids may stimulate
protein synthisis and reduce urea by recycling
nitrogen into non essential amino acids
- Low sodium and potassium feeds with
supplemental vitamins may be required

44. COPD
- Malnutrition is common
- Ventilatiun in respiratory failure has high
energy expenditure
- Over feeding with carbohydrate causes high
co2 production
- Feed should contain less carbohydrate and
high fat
- Fat oxidation produce 30% less co2

45. Hepatic failure
eg. AMINOLEBAN
- Impaired fat metabolism and carbohydrate
intolerance are common
- Use of branched chain ( instead of aromatic )
amino acids may improve mental status in
hepatic encephalopathy
- TPN must contain less sodium and volume
because of aldosterone induced water
retention

46. Complications of TPN
• Catheter related
-sepsis
-Thrombosis
-embolism
-pneumothorax
• Metabolic
-hyperglycemia
-hypercalcemia
• Electrolyte disturbances
• Liver dysfunction and gall stones
• Fluid overload

47. Stopping TPN
• Stop TPN when enteral feeding can restart
• Wean slowly to avoid hypoglycaemia
• wean TPN while introducing enteral feeding and stop
when enteral intake meets TEE

48. Monitoring of artificial nutrition
• Fluid balance (weight, intake vs. output)
• Glucose, electrolytes, BUN (daily until stable,
then 2x per week)
• Serum creatinine, albumin, phosphorus,
calcium, magnesium, Hb/Hct,
• WBC (baseline, then 2x per week)
• INR (baseline, then weekly)
• Micronutrient tests as indicated

49. Nutritional Balance
Nutritional Balance = Ninput - Noutput
1 g N = 6.25 g protein
Ninput = (protein in g x 6.25)
Noutput = 24h urinary urea nitrogen + non-
urinary N losses
(estimated normal non-urinary Nitrogen losses
about 3-4g/d)

50. Refeeding syndrome
• Occurs within few days of refeeding
• Underrecognized and can be fatal
• The shift from the use of fat as energy source
during starvation to use of carbohydrate during
refeeding
• Carbohydrate lead to augmentation of insulin
release with rapid intracellular passage of
phosphate , magnisium and potassium that lead
to hypophosphatemia , hypomagnesemia and
hypokalemia

51. • Hypophosphatemia lead to multiple organ
dysfunction ( muscle weakness,
rhabdomyolysis, cardic failure , immune
suppression, hemolytic anemia
,thrombocytopenia ,hallucinations and fits)

52. NICE 2006 criteria for who at risk for
refeeding syndrome
• 2 of the following
- BMI < 18.5 KG/M2
- Unintentional wt loss >10% in the last 3-6 months
- History of alcohol abuse or drug including insulin ,
diuritics , chemotheraby and antacids
• One of the following
- BMI < 16 kg/m2
- Unintentional wt loss > 15% in the last 3-6 months
- Little or no nutritional intake for more than 10 days
- Low level of K ,Ph , Mg prior to feeding

53. • Begin feeding at 25-50% of estimated calorie
requirement
• Increasing by 100 calories per day
• Restore circulatory volume and monitor fluid
balance and overall clinical status closely
• Serum phosphate ,mg, ca , k , urea and creatinine
should be checked daily for the first week
• parenteral phosphate administration (eg
18mmol/d) in addition to oral supplementation

54. Immunonutrition
• Use compounds that may improve metabolic and
immune response in critically ill patients
• Glutamine, an amino acid and primary energy
source for enterocytes , preserve intestinal
integrity
• Arginine stimulate immune function and nitrogen
balance
• Omega 3 unsaturated fatty acids from fish oil are
anti inflammatory agent and immunomodulators