parenteral nutrition

2.  Until the early 1960s, the use of intravenous nutrition
was restricted to high concentrations of dextrose and
electrolytes.
 In 1962, Wretlind and colleagues developed lipid
infusions as the principle source of calories for
parenteral feeding.
 In 1966, Dudrick and Rhoads developed parenteral
nutrition (PN) for patients who had lost their small
bowel.
 In 1976, Solassol and Joyeux developed the three-in-
one mixture by putting sugars, lipids and amino acids
in a single bag.
 In 1978, Shils and colleagues and Jeejeebhoy and
colleagues developed ‘home’ PN to reduce costs.

3.  Human nutrition is the provision to obtain the
essential nutrients necessary to support life
and health
 Nutrients are the substances that are not
synthesized in sufficient quantity in the body
and therefore must be supplied from diet
 Macronutrients mainly carbohydrates, fats,
protein, dietary fiber and water
 Micronutrients: vitamins, minerals and trace
elements

4.  Protein (Amino acids)
 Fat
 Carbohydrate
 Dietary fiber
 Water and electrolytes
 Vitamins
 minerals
 Trace elements

5.  Pts should be assessed for PEM as well as specific
nutrient deficiencies
History: assess for change in diet pattern (size,
number and content of meals)
 Unintentional weight loss
 Evidence of malabsorption
 Symptoms of specific nutrient deficiencies
 Look for factors which may increase metabolic
stress (infection, inflammation, malignancy)
 Functional status (bed ridden, suboptimally
active, fully active)

6.  By WHO criteria, pts can be classified by BMI as
underweight (<18.5),
normal weight (18.5-24.9),
overweight (25-29.9),
 class I obesity(30-34.9),
class II obesity(35-39.9)
class III obesity(>40)
 Pts who are extremely underweight (BMI<14
kg/m2) or those with rapid, severe weight loss
have high risk of death and should be considered
for admission to the hospital for nutritional
support

7.  Look for tissue depletion(loss of body fat and
skeletal muscle wasting)
 Assess muscle function (strength testing of
individual muscle groups)
 Fluid status: dehydration or fluid overload
 Look for sources of protein or nutrient losses:
large wounds, burns, nephrotic syndrome,
chronic diseases, GI losses of nutrients,
surgical drains.
 Lab parameters: plasma albumin, electrolytes,
vitamins and minerals

9.  Critical illness induces anorexia and the inability
to eat normally, predisposing patients to serious
nutritional deficits, muscle wasting, weakness,
and delayed recovery, longer stay in hospital
 For critically ill pts provision of specialized
nutritional support considered which represent
major advance in medical therapy
 Although at least 15-20% of pts in acute care
hospitals have evidence of significant
malnutrition, only a small fraction will benefit
from SNS

10.  Nutritional support, via either enteral or
parenteral routes, is used in three main settings:
(1) To provide adequate nutritional intake
during recuperative phase of illness or injury
(2) to support the pts during systemic response
to inflammation, injury or infection during an
extended critical illness
(3) pts with permanent loss of intestinal length
or function

11.  Decision to use SNS should be based on the
likelihood that preventing PEM will increase
the likelihood of recovery, reduce infection
rate, improve healing and shorten the stay in
hospital
 SNS should be recommended only when
potential benefits exceed risks, and it should
be undertaken with consent of the pt

13.  Efficacy studies have shown that
malnourished pts undergoing major
thoracoabdominal surgery benefit from SNS,
critical illness requiring ICU care, including
major burns, major trauma, severe sepsis,
closed head injuries and severe pancreatitis,
all benefit from early nutritional support, as
indicated by reduced mortality and morbidity

14.  Refers to feeding via a tube placed into the gut to
deliver liquid formulas containing all essential
nutrients
 Preferred route because of benefits derived from
maintaining the digestive, absorptive and
immunological barrier function of GIT
 Enteral/tube feeding is useful in pts who have
functional GIT, but who cannot digest or ingest
adequate amount of nutrients
 Short term (<6 weeks) tube feeding can be
achieved by nasogastric, nasoduodenal or
nasojejunal tubes

15.  Long term feeding (>6 wk) usually requires
gastrostomy or jejunostomy tube that can be
placed percutaneously by endoscopic (PEG) or
radiographic assistance
 Enteral feeding is often required in pts with
anorexia, impaired swallowing, or bowel
disease. The bowel and its associated
digestive organs derive 70% of their required
nutrients directly from food in lumen
 Enteral formulas: standard (osmolality- 300)
and modified
 Complications of enteral feeding include
mainly aspiration pneumonia and diarrhoea

16.  Enteral nutrition is associated with fewer complications than
parenteral nutrition and is less expensive to administer.
 However, the use of enteral nutrition alone often does not
achieve caloric targets.
 In addition, underfeeding is associated with weakness,
infection, increased duration of mechanical ventilation,
increased duration of hospital stay and death.
 Combining parenteral nutrition with enteral nutrition
constitutes a strategy to prevent nutritional deficit but may
risk overfeeding which has been associated with liver
dysfunction, infection, and prolonged ventilatory support.

17.  The consequences of major surgeries and PEM
can lead to hypermetabolism and subsequent
malnutrition. A strong association exist between
malnutrition and increased post operative
morbidity and mortality.
 The administration of TPN can prevent the effects
of starvation in pts with non functional GIT
 Parenteral nutrition should be considered if
energy intake has been inadequate for more than
7-10 days and enteral feeding is not feasible.
(based on ICU focused meta- analysis discussed
in 2009 ASPEN)

18. The gut should always be the
preferred route for nutrient
administration.
 Therefore, parenteral nutrition is
indicated generally when there is
severe gastro-intestinal dysfunction
(cannot take sufficient food or feeding
formulas by the enteral route) .

19.  It involves the continuous infusion of a
hyperosmolar solution containing
carbohydrates, proteins, fat and other
necessary electrolytes through an indwelling
catheter inserted into (usually) SVC to meet
the nutritional needs of the patient.
 PN through a peripheral vein is limited by
osmolality and volume constraints
 Solutions that contain more than 3%
aminoacid and 5% glucose are poorly
tolerated peripherally

20.  Peripheral parenteral nutrition (PPN)
administered through a peripheral intravenous
catheter.
The osmolarity of PPN solutions generally is limited
to 1,000 mOsm (approximately 12% dextrose
solution) to avoid phlebitis.
Thus, large volumes (>2,500 mL) are needed.
Temporary nutritional supplementation with PPN
may be useful
Generally intended as supplement to oral feeding
and is not optimal for critically ill pts

21.  Total parenteral nutrition (TPN)
provides complete nutritional support
The solution, volume of administration, and
additives are individualized based on an
assessment of the nutritional requirements.

22.  TPN formulation without lipid (2-in-1
solution)
Calories from amino acids- 20 to 25%
Calories from dextrose- 75-80%
 TPN formulation with lipid ( 3-in-1 solution)
 calories from amino acids- 20 to 25%
 calories from lipids- 20%
 calories from dextrose- 55 to 60 %

23.  Special solutions that contain low,
intermediate, or high nitrogen concentrations
as well as varying amounts of fat and
carbohydrate are available for pts with
diabetes, renal or pulmonary failure, or
hepatic dysfunction.

24.  Additives:
Electrolytes (i.e., sodium, potassium, chloride,
acetate, calcium, magnesium, phosphate) should be
adjusted daily.
The number of cations and anions must balance;
this is achieved by altering the concentrations of
chloride and acetate.
If the serum bicarbonate is low, the solution should
contain more acetate.
The calcium:phosphate ratio must be monitored to
prevent salt precipitation.

25.  Medications:
Albumin, H2-receptor antagonists, heparin, iron,
dextran, insulin, and metoclopramide can be
administered in TPN solutions. However, not all
medications are compatible with 3-in-1 admixtures.
Regular insulin should initially be administered
subcutaneously according to a sliding scale, based on a
determination of the blood glucose level. After a stable
insulin requirement has been established, insulin can be
administered in the TPN solution, generally at two thirds
of the daily subcutaneous insulin dose.

26.  Crystalline amino acid solutions containing 40-
50% essential and 50-60% non essential amino
acids are used to provide protein needs
 Some amino acid solutions have been modified:
rich in branched chain amino acids for hepatic
encephalopathy, rich in essential amino acid for
renal insufficiency pts
 Glucose in IV solutions is hydrated; each gm of
dextrose monohydrate provides 3.4 kcal. While
there is no absolute requirement of glucose in
most pts, providing >150g glucose/d maximizes
protein balance

27.  Lipid emulsions are available as 10%
(1.1kcal/ml) or 20% (2 kcal/ml) solutions and
provide energy as well as source of essential
fatty acids.
 Rate of infusion should not exceed 1
kcal/kg/h

28.  Climomel N5-800
 Clinimix N9G-20E
 Kabiven
 Vitrimix
 Celemix-G

29.  gastrointestinal cutaneous fistula
Renal failure (ATN)
 Short bowel syndrome
Severe burns
Hepatic failure
Crohn’s disease
Anorexia nervosa
Acute radiation enteritis
Acute chemotherapy toxicity
Prolonged ileus
Weight loss preliminary to major surgery

30. Energy
 Basal energy requirement is the function of the
individual's weight, age, gender, activity level and
the disease process
 The major components of energy output are
resting energy expenditure and physical activity;
minor sources include the energy cost of
metabolizing food and shivering thermogenesis.
 Total energy expenditure= resting energy
expenditure (70% of TEE) +thermic effect of food
(10% of TEE) + energy expenditure of physical
activity (20% of TEE)

31.  Average energy intake is about 2600 kcal/d for
men and 1900 kcal/d for female, though these
estimates vary with body size and activity level
 Formula for estimating REE are useful for
assessing the energy needs of an individual
whose weight is stable
 For males, REE=900+10m, and for females,
REE=700+7m, where m is mass in kilograms
 Calculated REE is the adjusted for physical
activity level (multiplying by 1.2 for sedentary,
1.4 for moderately active and 1.8 for very active)

32. TEE = REE + Stress Factor + Activity
Factor
Rest Energy Expenditure
 Adults (18-65) 20-30 kcal/kg
 Elderly (65+) 25 kcal/kg
 For burns Patients 30-35kcal/kg
Other factors:
 Pregnancy: Add 300 kcal/day
 Lactation: Add 500 kcal/day
 Obese or Super obese 15-20 kcal/kg

33. peritonitis + 15%
• soft tissue trauma + 15%
• fracture + 20%
• fever (per oC rise) + 13%
• Moderate infection + 20%
• Severe infection + 40%
• <20% BSA Burns + 50%
• 20-40% BSA Burns + 80%
• >40% BSA Burns + 100%

34. BMI (kg/m2) Energy requirement (kcal/kg/d)
15 35-40
15-19 30-35
20-24 20-25
25-29 15-20
30 and >30 <15
These values are recommended for critically ill pts and obese pts;
add 20% of total calories in estimating energy requirement in non
critically ill pts

35.  Requirement 2g/kg/day
 1grams=5kcal/g
 40-50 percent of total nutrition
 Generally, because glucose is an essential
tissue fuel, glucose and amino acids are
provided parenterally until the level of resting
energy expenditure is reached. Fats are
added thereafter

36.  Requirement 3 g/kg/day
 1 gram= 9kcal/g
 30-40 percent of nutrition
 Liver can synthesize most fatty acids, but
humans lack the desaturase enzyme needed
to produce n-3 and n-6 fatty acid series.
Therefore linoleic acid should constitute at
least 2% and linolenic acid at least 0.5% of
daily caloric intake to prevent essential fatty
acid deficiency

37. Clinical condition requirement
normal 0.8
Metabolic stress (illness, injury) 1.0-1.5
Acute renal failure (undialyzed) 0.8-1.0
hemodialysis 1.2-1.4
Peritoneal dialysis 1.3-1.5
Additional protein intake may be needed to compensate for
excess protein loss in specific patient population such as
burn injuries, open wounds, protein losing Enteropathy /
Nephropathy. A lower protein intake may be necessary in
patient with chronic renal insufficiency who are not treated
by dialysis and certain patients with hepatic encephalopathy

38.  The standard enteral and parenteral formulas
contain protein of high biological value and
meet the requirements for the eight essential
amino acids
 Protein or nitrogen balance provides a
measure of feeding efficacy of PN or EN
 Calculated as protein intake/6.25 minus 24h
urine urea nitrogen plus 4g nitrogen, which
reflects the other losses

39. Nitrogen Balance = N input - N output
6.25 g protein provides 1 g of nitrogen as
100grams contains 16 g nitrogen
N input = (protein in g / 6.25)
N output = 24h urinary urea nitrogen + non-urinary
N losses
 +4 to + 6: Net anabolism
 +1 to - 1: Homeostasis
 -2 to – 1: Net catabolism

40. ESTIMATING ADULT FLUID REQUIREMENTS
By caloric intake : 1ml/calorie
 Example: 1800 calorie diet = 1800 calories x
1ml= 1800ml
By body weight and age : average requirement
is 30 ml/kg/d
 16-55 years 35 ml/kg/d
 56-65 years 30 ml/kg/d
 > 65 years 25 ml/kg/d

41.  Sodium 70 – 100 mEq/day
 Chloride 70 – 100 mEq/day
 Potassium 70 – 100 mEq/day
 Calcium 10 – 20 mEq/day
 Magnesium 15 – 20 mEq/day
 Phosphorus 40-60 mEq/day
 Acetate 0 – 60 mEq/day

42.  Vitamin A 3300 IU
 Vitamin D 200 IU
 Vitamin E 10 IU
 Vitamin K - 150 mcg
 Ascorbic acid 100 mg
 Folic Acid 0.4 mg
 Niacin 40 mg
 Riboflavin (B2) 3.6 mg
 Thiamin (B1) 3 mg
 Pyridoxine (B6) 4 mg
 Cyanocobalamin (B12) 5 mcg
 Pantothenic acid 15 mg
 Biotin 60 mcg

43.  Zinc 2.5-4 mg
 Copper 0.5-1.5mg
 Chromium 10-15 mcg
 Selenium 20-60 mcg
 Manganese 150-800 mcg

44.  Introduction of TPN should be gradual. For
example, approximately 1,000 kcal is provided
the first day. If there is metabolic stability (i.e.,
normoglycemia), this is increased to the caloric
goal over 1 to 2 days.
 TPN solutions are delivered most commonly as a
continuous infusion. A new 3-in-1 admixture
bag of TPN is administered daily at a constant
infusion rate over 24 hours. Additional
maintenance intravenous fluids are unnecessary,
and total infused volume should be kept constant
while nutritional content is increased.

45.  Cyclic administration of TPN solutions may be useful
for
(1) those who will be discharged from the hospital
and subsequently receive home TPN,
(2) those with limited intravenous access who require
administration of other medications, and
(3) those who are metabolically stable and desire a
period during the day when they can be free of an
infusion pump.
 Cyclic TPN is administered for 8 to 16 hours, most
commonly at night. This should not be done until
metabolic stability has been demonstrated for
patients on standard, continuous TPN infusions.

46.  Venous access
 The infusion of hyperosmoler nutrient solution
requires a large bore, high flow vessel to
minimize vessel irritation and damage.
 Percutaneous subclavian vein catheterization
and PICC are the most commonly used
techniques for parenteral nutrition
 Catheter can be placed via the subclavian vein,
the jugular vein (less desirable because of the
high rate of associated infection), or a long
catheter placed in an arm vein and threaded
into the central venous system (a peripherally
inserted central catheter line)
 Position of catheter is confirmed by radiograph

48. ADVANTAGES DISADVANTAGES
 Bed side technique
 Avoids complications
of central venous
catheter
 Avoid multiple venous
cannulations
 Hypertonic solutions
can be given
 Trained personnel is
needed
 Line blockage
 Mal position
 Phlebitis
 Line sepsis
 thrombosis

51. advantages disadvantages
 Central access needed
 Multiple lumen can be
used in acute
emergency
 Hypertonic solutions
can be given
 Can be placed for than
6 weeks
 Inserted in theatre
 Increase infection rate
 Multiple complications

53. advantages disadvantages
 Convenient exit site
 Long lasting than non
tunnels
 Hypertonic solutions
can be given
 Removal needs surgical
dissection
 Catheter related sepsis
 Other complications

56. Clinical Data Monitored Daily
General sense of well-being
Strength as evidenced in getting out of bed, walking, resistance exercise as
appropriate
Vital signs including temperature, blood pressure, pulse, and respiratory rate
Fluid balance: weight at least several times weekly, fluid intake (parenteral and
enteral) vs. fluid output (urine, stool, gastric drainage, wound, ostomy)
Parenteral nutrition delivery equipment: tubing, pump, filter, catheter,
dressing
Nutrient solution composition

57. Laboratory Daily
Finger-stick glucose Three times daily until stable
Blood glucose, Na, K, Cl, HCO3, BUN Daily until stable and fully
advanced, then twice weekly
Serum creatinine, albumin, PO4, Ca,
Mg, Hb/Hct, WBC
Baseline, then twice weekly
INR Baseline, then weekly
Micronutrient tests As indicated

58.  Discontinuation of TPN should take place
when the patient can satisfy 75% of his or her
caloric and protein needs with oral intake or
enteral feeding.
 To discontinue TPN, the infusion rate should
be halved for 1 hour, halved again the next
hour, and then discontinued.
 Tapering in this manner prevents rebound
hypoglycemia from hyperinsulinemia.
 It is not necessary to taper the rate if the
patient demonstrates glycemic stability.

59. Complications
Of TPN
Mechanical
metabolicinfectious

60. Air embolism
 pneumothorax
 hemothorax
Cardiac tamponade
Injuries to arteries and veins
Injury to thoracic duct
Brachial plexus injury

61.  Early or nutrient related
 hyperglycemia
 hypoglycemia
 hyperlipidemia
 refeeding syndrome
 late or related to long term administration
 hepatic dysfunction
Steatosis, steatohepatitis, lipidosis, cholestasis,
cirrhosis
 biliary complications: acalculous cholecystitis, Gb
sludge, cholelithiasis
Metabolic bone disease: osteomalaacia, osteopenia

62.  Fluid overload
 Hypo/hypernatremia
 Hypercalcemia
 Hypo/hyperkalemia
Infection :
 Catheter related sepsis is most common life
threatening complication
 Causes: staph epidermidis and staph aureus,
enterococcus, candida, E coli, psuedomonas,
klebsiella etc in immunocompromised pts

63.  Severe electrolyte and fluid shifts that may
result from refeeding after severe weight loss
(PEM)
 Hypophosphatemia is the hallmark of
refeeding syndrome due to shift from fat to
glucose metabolism.
 Hypokalemia and hypomagnesemia
 ↓K and ↓PO4→ ATP deficiency which can be
life threatening.

64.  Store reconstituted PN bags in a refrigerator until
use
 Always use aseptic techniques while connecting and
infusing PN
 Always use an infusion set with in-built air vent and
0.2 m filter
 Never insert a needle for air venting in a PN bag
 Never add any medication to the PN bag
 Avoid frequent changes in the formulation of the PN
solution
 Infuse the prescribed volume and avoid wastage of
PN solution

65.  Clinical trials and meta-analysis of parenteral
feeding in the perioperative period have
suggested that preoperative nutritional
support may benefit some surgical patients,
particularly those with extensive malnutrition.
 Short-term use of parenteral nutrition in
critically ill patients (duration <7 days) when
enteral nutrition may have been instituted is
associated with higher rates of infectious
complications

66.  Parenteral feeding with complete bowel rest
results in augmented stress hormone and
inflammatory mediator response to an
antigenic challenge .
 In cancer patients, parenteral nutrition has
not been shown to benefit clinical response,
survival, or toxic effects of chemotherapy,
while infectious complications increased.
 Following severe injury, parenteral nutrition is
associated with higher rates of infectious
risks when compared with enteral feeding

67.  the early initiation of parenteral nutrition to
supplement insufficient enteral nutrition
during the first week after ICU admission in
severely ill patients at risk for malnutrition
appears to be inferior to the strategy of
withholding parenteral nutrition until day 8
while providing vitamins, trace elements, and
minerals. Late parenteral nutrition was
associated with fewer infections, enhanced
recovery, and lower health care costs

68.  Subjects receiving intravenous feedings and
bowel rest had significantly exaggerated
response to injury

69.  Strict asepsis
 24-hr TPN prepared at a time
 Changing infusion sets daily
 New amino acid, lipid bottles daily
 Separate IV access for other drugs
 Serum Na, K on alt. days;
renal parameters biweekly;
LFT, triglycerides weekly