Presentation at Kathmandu Model Hospital by Dr. Kiran Pandey, MS General Surgery Resident, NAMS (National Acadamy of Medical Sciences)

1. Namaskar
ENTERAL AND PARENTERAL NUTRITION

2. ENTERAL AND PARENTERAL NUTRITION
Dr. Kiran Pandey
MS GS Resident (NAMS)
Kathmandu Model Hospital

3. General Outlines
INTRODUCTION
GOALS
Outcomes
CONTRAINDICATION
 INDICATIONS
 COMPLICATIONS

4. Introduction
Nutrition support refers to enteral or parenteral
provision of calories, protein,
electrolytes, vitamins, minerals, trace elements,
and fluids.

5. Concerns
Malnutrition occurs in about 30 per cent of surgical
patients with gastrointestinal disease and in up to
60 per cent of those in whom hospital stay has
been prolonged because of postoperative
complications.
• Frequently unrecognised
• Patients malnutrition have a higher risk of
complications and an increased risk of death in
comparison with patients who have adequate
nutritional reserves

6. Metabolic response to starvation
• conversion of 200 g of liver glycogen into glucose.
• Additional stores of glycogen exist in muscle (500 g
• Low plasma insulin
• High plasma glucagon
• Hepatic glycogenolysis
• Protein catabolism
• Hepatic gluconeogenesis
• Lipolysis: mobilisation of fat stores (increased fat oxidation)–
• overall decrease in protein and carbohydrate oxidation
• Adaptive ketogenesis
• Reduction in resting energy expenditure (from approximately
• 25–30 kcal/kg per day to 15–20 kcal/kg per day

7. Metabolic response to trauma and
sepsis
• Increased counter-regulatory hormones.
• Increased energy requirements (up to 40 kcal/kg per
day)
• Increased nitrogen requirements
• Insulin resistance and glucose intolerance
• Preferential oxidation of lipids
• Increased gluconeogenesis and protein catabolism
• Loss of adaptive ketogenesis
• Fluid retention with associated hypoalbuminaemia

8. GOALS
 To alter the course and outcome of the critical illness.
 During recovery from acute illness anabolism >catabolism
1. Provides substrate for the anabolic state
2. Provide carbohydrates as a preferred source of energy
during this time as fat mobilization will be impaired
3. Provides protein to reduce muscle breakdown for
GLUCONEOGENESIS

9. NUTRITIONAL ASSESSMENT
• Laboratory techniques
• No single biochemical measurement
• Albumin is not a measure of nutritional status.
• Low serum albumin level (<30 g/L) is an
indicates poor prognosis, invariably occurs
because of alterations in body fluid
composition and increased capillary
permeability related to ongoing sepsis

10. NUTRITIONAL ASSESSMENT
Body weight and anthropometry
Estimate weight loss.
BMI of less than 18.5 indicates nutritional impairment and a BMI below 15 is
associated with significant hospital mortality.
 BMI<18.5
 Unintentional loss of>5 lb or 5% of the body weight over one month.
 unintentional loss of more than 4.5 kg (10 lb) or 10% of body weight over six
months.
 Temporal muscle wasting, sunken supraclavicular fossae, decreased adipose
stores, and
Skinfold thicknesses and mid-arm circumference
Bioelectrical impedence analysis (BIA) permits estimation of intra- and
extracellular fluid volumes
Clinical

12. MUST

13. Signs of vitamin deficiencies

14. Daily requirements
sodium: 50–90 mM/day;
potassium: 50 mM/day;
calcium: 5 mM/day;
magnesium: 1 mM/day.
• total energy requirement of a stable patient
with a normal or moderately increased need is
approximately 20–30 kcal/kg

15. Fat
• Energy during parenteral nutrition should be
given as a mixture of fat together with glucose.
• No any particular ratio of glucose to fat until
• the basal requirements for glucose (100–200
g/day) and essential fatty acids (100–200 g/week)
are met.
• Immunosuppressive effects of LCT emulsions
occurs if the recommended infusion rates (0.15
g/kg per hour)

16. Carbohydrate
• Obligatory glucose requirement is equivalent
to about 2 g/kg per day
• Physiological maximum glucose that can be
Oxidised is 4 mg/kg per minute (1500
kcal/day in a 70-kg person), with the
nonoxidise glucose converted to fat.

17. Protein
• The basic requirement for nitrogen in patients
without pre-existing malnutrition and without
metabolic stress is 0.10–0.15 g/kg per day. In
hyper-metabolic patients, the nitrogen
requirements increase to 0.20–0.25 g/kg per
day.

18. Vitamins, minerals and trace
elements
The water-soluble vitamins B and C act as coenzymes in
collagen formation and wound healing
Postoperatively, the vitamin C requirement increases
to 60–80 mg/day.
Supplemental vitamin B12 is often indicated
in patients who have undergone intestinal resection or
gastric surgery and in those with a history of alcohol
dependence.
Absorption of the fat-soluble vitamins A, D, E and K is
reduced in steatorrhoea and the absence of bile.

19. Vitamins and trace elements:
Have a lower mortality rate than patients who
did not receive vitamins or trace elements.
Improvement in the duration of mechanical
ventilation
Provide vitamins and trace elements to most
critically ill patients, regardless of the type of
nutrition support that they are receiving.

20. Outcome:
In Adequately nourished patients:
Enteral nutrition may decrease the incidence of
infection in critically ill patients but no
mortality benefit
Mechanism unknown , but preservation of gut
immune function and reduction of
inflammation may play a role

21. Outcome:
In patient with malnutrition:
Most studies excluded malnourished patient
It is believed enteral nutrition beneficial to
patient with prolonged period of inadequate
intake.
Some observational evidence shows
progressive
 caloric deficit increase mortality.

22. Parenteral nutrition(PN)
Early parenteral nutrition (up to 48 hours) does not alter
mortality but increase risk of nosocomial infection
No consistent evidence in critically ill patients suggesting
that early provision of parenteral nutrition improves
ventilator-free days or length of stay in the ICU or
hospital
Optimal time for starting PN is unknown
Typically is not started in one to two weeks

23. Reviewing Articles

24. Reviewing Articles

25. Enteral access:
 Gastric(NG or OG tube, PEG tube, percutaneous radiologic
gastrostomy tubes, and surgical gastrostomy tubes)
 Post-pyloric usually ending in the first or 2nd part of duodenum
 Prolonged inability to tolerate gastric feeding
 Gastric outlet obstruction
 Duodenal obstruction
 Gastric or duodenal fistula
 Severe GERD
 The inability to have a gastric
 enteral access tube due to
altered anatomy

26. Enteral access:

27. Formulation for EN:
• Standard
• Concentrated
• Predigested

28. Standard:
 Isotonic to serum, Lactose-free
Caloric density of approximately 1 kcal/mL
Intact (non hydrolyzed) protein content of
about 40 g/1000 ml (40 g/1000 kcal)
Mixture of simple and complex carbohydrates
Long-chain fatty acids
Essential vitamins, minerals, and
micronutrients

29. Concentrated:
Critically ill patients requiring volume
restriction ( patients with respiratory failure,
or volume overload).
Is similar to standard EN, but mildly
hyperosmolar
Has a caloric density of 1.2, 1.5, or 2.0 kcal/mL

30. Predigested:
Predigested enteral nutrition differs from
standard enteral nutrition:
 the protein is hydrolyzed to short-chain peptides and
the carbohydrates are in a less complex form.
 The total amount of fat may be decreased
 increased proportion of medium-chain triglycerides
 has caloric density of 1 or 1.5 kcal/mL.

31. When to use predigested?
• Thoracic duct leak, chylothorax, or chylous ascites,
since the medium-chain triglycerides do not enter
the lymphatic capillaries in the small intestine
• Digestive defects (eg, malabsorptive syndromes that
are unresponsive to supplementation of pancreatic
enzymes)
• Failure to tolerate standard enteral nutrition

32. Monitoring:
 Patients on tube feeding are at risk for fluid imbalance, gut
dysfunction, and electrolyte imbalance
 Gastric residuals should be measured if
abdominal pain
abdominal distension, or
deterioration in hemodynamics or overall status.
 If GRV is measured, volumes of <500 ml,
Continue the feeds unless other signs of intolerance, such
as distension, nausea, or vomiting present.

33. Complications of EN:
Aspiration
Diarrhea
Metabolic abnormalities
Mechanical complication

34. Diarrhea
 15-18% of critically ill patient
 Alteration of intestinal transit or microflora
 Usually A/W concomitant use of medications as antibiotic,
PPIs, analgesics
 fiber is the best accepted therapeutic intervention for
enteral nutrition associated diarrhea , but it is
contraindicated in patients with impaired peristalsis

35. Metabolic abnormalities:
Hyperglycemia, micronutrient deficiencies, and
refeeding syndrome.
Refeeding synd:
Potentially fatal resulting from rapid changes in
fluids and electrolyte when malnourished patient
is given oral , enteral , parenteral feeding.
Manifest as severe hypophosphatemia (CV
collapse, resp. failure, Rhabdomyolysis, seizure,
delirium)
Hypo Mg and hypo K can occur.

36. Mechanical :
 Constipation
Fiber bezoar on enteral feeding with fiber.
More prevalent in patients with impaired
peristalsis like being on vasopressors.
Cause impaction, bowel distention,
perforation, and death if not treated early.

37. Contraindications:
Hemodynamically unstable patients
predisposed to bowel ischemia.
Hemodynamic instability is not by it self
contraindication for enteral feeding if there is
evidence of good perfusion and intravascular
resuscitation
Bowel obstruction , severe and protracted
ileus, major UGIB,
intractable vomiting and diarrhea,
High output fistula, severe

38. Indication:
No contraindication to enteral nutrition,
Start enteral feeding early(within 48hrs)
lowers mortality and fewer infection.
For adequately nourished patients who have
contraindications to enteral nutrition
Should NOT initiate early parenteral nutrition
before one to two weeks, parenteral nutrition
increases the risk of infection and prolong
mechanical ventilation, ICU stay, and hospital
stay

39. Indication:
For inadequately nourished patients who have
contraindications to enteral nutrition that are
expected to persist for a week or more, we
can initiate PN within the first few days.
Although the effects of parenteral nutrition in
such patients are unknown; but failure to treat
the malnourishment will result in a
progressive caloric deficit, which is associated
with increased morbidity.

40. Parenteral nutrition:
Appropriate access must be obtained
Composition and infusion rate determined.
PN given for more than a few days must be via
central venous catheter
high osmotic load is not tolerated by
peripheral veins
Peripheral vein if it is significantly more
diluted, so called peripheral parenteral
nutrition.

41. Parenteral Access

42. Total parenteral nutrition (TPN)
• Provision of all nutritional requirements by
means of the intravenous route and without the
use of the gastrointestinal tract.
• Parenteral nutrition is indicated when energy and
protein needs cannot be met by the enteral
administration of these substrates.
• Common clinical indications , massive resection
of the small intestine, intestinal fistula or
prolonged intestinal failure for other reasons
• catheter inserted in the central vein or via a
peripheral line.

43. Total parenteral nutrition (TPN)
Contains safe and non-toxic fat emulsions
isotonic and have carbohydrates, fats and
amino acids mixed together.
The energy requirements are rarely in excess of
2000 kcal/day (25–30 kcal/kg per day).

44. Peripheral Venous Access
short-term feeding of up to 2 weeks
catheter inserted into a peripheral vein and
manoeuvred into the central venous system
(peripherally inserted central venous catheter
(PICC) line) or by using a conventional short
cannula in the wrist veins.
mean duration of survival of 7 days.
Leads to thrombophlebitis damaging the vein
irrevocably

45. Central Venous Access
Parenteral nutrition:
 Long-term parenteral nutrition requires a tunneled
central venous catheter (eg,Hickman catheter,
Groshong catheter, or implanted infusion port) or a
peripherally inserted central catheter (PICC)
 Catheter inserted via subclavian or internal or external
jugular vein.
 Post-insertion chest x-ray is essential before feeding is
started to rule out pneumothorax and catheter tip in
the distal superior vena cava to minimise the risk of
central venous or cardiac thrombosis.

46. Dextrose:
Variety of concentration, most commonly
40,50 and 70 percent
Titrated according to individual factors such as
severity of the illness, caloric needs of the
patients an ability to tolerated fluid volume.
Caloric contribution of dextrose is 3.4kcal/gm

47. Amino acid and electrolytes:
AA stock solutions come in concentration of
5.5 to 15 %
Higher concentration are used to minimize
volume and electrolytes delivered to patient.
AA solutions contains most essential and non-
essential AAs.
Except arginine and glutamine.
Caloric contribution of AA is 4kcal/gm

48. Lipids
Lipid emulsion consists of long-chain omega-6
triglyceride derived from soybean and safflower
oils and then emulsified using eg phospholipids
and glycerin.
The caloric contribution of a typical lipid emulsion
is 2 kcal/mL in 20 percent emulsion and 1.1
kcal/mL in 10 percent emulsion.
Use of intravenous fat emulsions should be done
with care in patients with prior allergy to eggs as
very rare allergic reactions have been reported.

49. Monitoring:
Routine monitoring is fluid intake and output
Measure serum electrolytes, glucose, calcium,
magnesium, and phosphate daily, or more,
until they are stable.
Measure aminotransferases, bilirubin, and
triglyceride at least once each week during
treatment.

50. Complication:
Blood stream infection
Metabolic affect
Complications related to Venus access

51. Blood stream infection:
Factors A/W blood stream infection :
 Poor patient hygiene
 Inserting central Cath in emergent circumstances
 Severity of illness
 Duration of central Venous catheterization
 Proper hand hygiene and maximal barrier
precautions during insertion of the central
venous catheter are associated with fewer
bloodstream infections

52. Metabolic affect:
Includes hyperglycemia, serum electrolyte
alterations, macro- or micro-nutrient excess or
deficiency, re-feeding syndrome , Wernicke's
encephalopathy , and hepatic dysfunction.

53. Venous access:
Bleeding
Vascular injury
Pneumothorax
Venous thrombosis
Arrhythmia
Air embolism.

54. Calories:
Energy expenditure is high in the critically ill.
Improvement in mechanical ventilation, pain,
anxiety, and temperature control, the caloric
expenditure of the critically ill may not exceed
resting energy expenditure.
Start with 8 to 10 kcal/kg per day.
Attempting to achieve a goal of 25 to 30
kcal/kg per day after one week .

55. Review

56. Protein:
Mild to moderate illness 0.8 to 1.2 g/kg
protein per day.
Critically ill patients 1.2 to 1.5 g/kg per day.
Patients with severe burns may benefit from
as much as 2 g/kg per day.

57. Summary:
 For critically ill surgical patients without contraindications to enteral
nutrition, it is recommended early (eg, within 48 hours) enteral
nutrition.
 For critically ill patients who are hemodynamically unstable and
have not had their intravascular volume fully resuscitated early
enteral nutrition is contraindicated
 For adequately nourished patients who have contraindications to
enteral nutrition, it is recommended NOT initiating early parenteral
nutrition While the optimal time for starting parenteral nutrition in
these patients is unknown, usually it is not recommended to start
parenteral feeding before one to two weeks.

58. Summary contd…
 For malnourished patients who have contraindications
to enteral nutrition that are expected to persist one
week or less, it has been suggested NOT initiating
parenteral nutrition.
 For malnourished patients who have contraindications
to enteral nutrition that are expected to persist greater
than one week, then suggest parenteral nutrition .
 An acceptable initial nutritional goal is 8 to 10 kcal /kg
per day and then 18 to 25 kcal/kg/day and 1.5 grams of
protein/kg per day after five to seven days.

59. References
• Uptodate
• Bailey & Love's Short Practice of Surgery
• Harrsion principle of internal medicine
• Pubmed
• NEJM

60. Best Wishes