‫للا الرَّ ْح َم هن الرَّ هح همم‬
‫بسم ه‬
‫” َذله ُك َما هممَّا َعلَّ َم هني َربِّي‬
‫إه ِّني َت َر ْك ُ‬
‫اّلل“‬
‫ون هب َّ ه‬
‫ت هملَّ َة َق ْو ٍم ال م ُْؤ هم ُن َ‬
Ain-Shams university
Faculty of Medicine
Department of Anesthesiology, ICU, and Pain
management
CME Program – ICU course
Parenteral
Nutrition
By
Ahmed El-Shaer, MD
Def. :a method of feeding patients by
infusing a mixture of all necessary
nutrients into the circulatory system,
thus bypassing the GIT.
Also referred to as:
intravenous nutrition,
parenteral alimentation, and
artificial nutrition.
The gut should always be the preferred
route for nutrient administration.
Therefore, parenteral nutrition is indicated
generally when there is severe gastrointestinal dysfunction (patients who cannot
take sufficient food or feeding formulas by
the enteral route) .
Categories of PN
If enteral feeding is completely stopped or
ineffective, Total Parenteral Nutrition is
used (TPN).
If enteral feeding is just “not enough” ,
supplementation with Partial Parenteral
Nutrition (PPN) is indicated.
INDICATIONS
In well-nourished adults, 7 - 10 days of
starvation with conventional intravenous
support (using 5% dextrose solutions) is
generally accepted.
If the period of starvation is to extend beyond
this time, or the patient is not well-nourished,
Total Parenteral Nutrition (TPN) is necessary
to prevent the potential complications of
malnutrition.
Indications for TPN
Short-term use
Bowel injury, surgery, major trauma or burns
Bowel disease (e.g. obstructions, fistulas)
Severe malnutrition
Nutritional preparation prior to surgery.
Malabsorption - bowel cancer
Severe pancreatitis
Malnourished patients who have
of aspiration
Long-term use (HOME PN)
Prolonged Intestinal Failure
Crohn’s Disease
Bowel resection
high risk
Partial Parenteral Nutrition:
PPN can be used to supplement Ordinary or
Tube feeding esp. in malnourished patients.
Indications:
Short bowel syndrome
Malabsorption disorders
Critical illness or wasting disorders
Enteral versus parenteral
nutrition
As far as gastrointestinal failure is concerned,
long term parenteral nutrition is a life-saving
procedure.
Enteral nutrition has the advantage over
parenteral nutrition of lower % of infectious
complications.
Parenteral nutrition has been shown to lead to
changes in intestinal morphology and function
and an increase in permeability (with higher %
of bacterial translocation)
Nutritional Requirements
Energy: Glucose
Lipid
Amino acids (Nitrogen)
Water and electrolytes
Vitamins
Trace elements
Requirements:
Energy
Basal energy requirements are a function of
the individual's weight, age, gender, activity
level and the disease process.
The estimation of energy requirements for
parenteral nutrition relies on predictive
equations.
Hospitalized adults require approximately 25-30
kcal/ kgBW/day.
However, these requirements may be greater in
patients with injury or infection.
Energy Requirements
Patient condition
Basal
metabolic
rate
Approximate energy
Requirement
(kcal/kg/day)
No postoperative
complications, GIT
fistula without infection
Normal
25-30
Mild peritonitis, long-bone
fracture, mild to moderate
injury, malnourished
25% above
normal
30-35
Severe injury or infection
50% above
normal
35-45
Burn 40-100% of total body Up to 100%
45-80
surface
above normal
Requirements:
Energy Sources: Glucose
The most common source of parenteral energy supply
is glucose, being:
 Readily metabolized in most patients,
 provides the obligatory needs of the substrate , thus
reducing gluconeogenesis and sparing endogenous
protein.
 1 gm of glucose gives 4 Kcals.
Most stable patients tolerate rates of 4-5 mg.kg-1.Min-1,
but insulin resistance in critically ill patients may lead
to hyperglycemia even at these rates, so insulin
should be incorporated acc. to blood sugar levels.
Requirements:
Energy Sources: Glucose
Route
Glucose in 5% solution can be safely
administered via a peripheral vein, but higher
concentrations require a central venous line.
20, 25, or even 50 % solutions are needed to
administer meaningful amounts of energy to
most patients for proper volume administration.
Requirements:
Energy Sources: Lipid
Fat mobilization is a major response to stress and
infection.
Triacylglycerols are an important fuel source in
those conditions, even when glucose availability is
adequate.
Need to be restricted in patients with
hypertriglyceridemia.
Requirements:
Energy Sources: Lipid
Lipids are also a source for the essential fatty
acids which are the building blocks for many of the
hormones involved in the inflammatory process as
well as the hormones regulating other body
functions.
Ideally, energy from fat should not exceed 40% of
the total (usually 20-30%).
Requirements:
Energy Sources: Lipid
Fat emulsions can be safely administered via
peripheral veins, provide essential fatty acids, and
are concentrated energy sources for fluid-restricted
patients.
They are available in 10, 20 and 30% preparations.
Though lipids have a calorific value of 9Kcal/g, the
value in lipid emulsions is 10Kcal/g due to the
contents of glycerol and phospholipids.
Requirements:
Nitrogen
Protein (or amino acids, the building blocks of
proteins) is the functional and structural
component of the body, so fulfilling patient’s
caloric needs with non-protein calories (fat and
glucose) is essential.
Protein requirements for most healthy
individuals are 0.8 g/kg/day.
Requirements:
Nitrogen
With disease, poor food intake, and inactivity, body
protein is lost with the resultant weakness and
muscle mass wasting.
Critically ill patients may need as high as 1.5-2.5 g
protein/kg/day depending on the disease process:
(major trauma or burn > infection or after surgery > standard)
The amount should be reduced in patients with
kidney or liver disease.
Requirements:
Nitrogen
Daily Protein requirements
Condition
Basic requirements
Slightly increased
requirements
Moderately increased
requirements
Highly increased
requirements
Reduced requirements
Example
Normal person
Post-operative, cancer,
inflammatory
Sepsis, polytrauma
requirement
0.5-1g/Kg
1.5g/Kg
Peritonitis, burns,
2.5g/Kg
Renal failure, hepatic
encephalopathy
0.6g/Kg
2g/Kg
Requirements:
Nitrogen
Nitrogen Balance =
Protein intake in grams ÷ 6.25 – UUN (in grams) + 3
The nitrogen lost in urine derives primarily from amino
acids released by protein breakdown in response to
catabolic mediators that include stress hormones
(corticosteroids, catecholamines) and cytokines.
It is a way to assess the sufficiency of protein intake
for the patient.
Requirements:
Nitrogen
Parenteral amino acid solutions provide all known
essential amino acids.
Available a.a. preparations are 3.5 - 15 % (ie
contains 3.5-15 gms of protein or a.a.s/100 mL
solution).
1gm of protein = 0.16 gm of N2.
Requirements:
Nitrogen
Special a.a. solutions are also available containing
higher levels of certain a.a.s, most commonly the
branched-chain ones (valine, leucine and
isoleucine), aimed at the management of liver
diseases, sepsis and other stress conditions.
Conversely, solutions containing fewer a.a.s
(primarily the essential ones) are available for
patients with renal failure.
Requirements:
Nitrogen
Arginine was added to enteral formulae
claiming positive effects on immune function
and length of hospital stay.
In some clinical trials, glutamine-enriched
solutions improved nitrogen balance and gut
morphology.
Requirements:
Fluids and electrolytes
20–40 mL/kg - daily – young adults
30 mL/kg – daily – older adults
Sodium, potassium, chloride, calcium,
magnesium, and phosphorus ( as per the table)
Daily lab tests to monitor electrolyte status
Requirements:
Fluids and electrolytes
Nutrient
Water
Sodium
Potassium
Magnesium
Calcium
Phosphate
Chloride/Acetate
Requirements (/Kg/day)
20-40 mL
0.5-1.0 mmol
0.5-1.0 mmol
0.1-0.2 mmol
0.05-0.15mmol
0.2-0.5mmol
So a to maintain acid-base balance
(normally 0.5 mmol for Cl- , & 0.1mEq for Acetate)
Requirements:
Fluids and electrolytes
Normalization of acid-base balance is a priority and
constant concern in the management of critically ill
patients.
Most electrolytes can be safely added to the
parenteral amino acid/dextrose solution.
Sodium bicarbonate in high concentrations will tend to
generate carbon dioxide at the acidic pH of the amino
acid/glucose mix.
Requirements:
Vitamins
These requirements are usually met when
standard volumes of a nutrient mix are provided.
Increased amounts of vits are usually provided to
severely ill patients.
Vitamins are either fat soluble (A,D,E,K) or water
soluble (B,C). Separate multivitamin commercial
preparations are now available for both.
Requirements:
Vitamins
Multivitamin formulations for parenteral use for
adult patients usually contain 12 vitamins at levels
estimated to provide daily requirements.
Additional amounts can be provided separately
when indicated.
Most adult vitamin formulae do not contain vitamin
K, which is added according to the patient’s
coagulation status.
Requirements:
Trace minerals
These are essential component of the parenteral
nutrition regimen.
A multi-element solution is available commercially,
and can be supplemented with individual minerals.
may be toxic at high doses.
Iron is excluded, as it alters stability of other
ingredients. So it is given by separate injection (iv
or im).
Requirements:
Trace minerals
minerals excreted via the liver, such as copper and
manganese, should be used with caution in patients
with liver disease or impaired biliary function.
Mineral
Zinc
Copper
Recommended dietary
allowance (RDA) for daily
oral intake (mg)
15
2-3
Suggested daily
intravenous intake
(mg)
2.5-5
0.5-1.5
Manganese
Chromium
Iron
2.5-5
0.05-0.2
10 (males)-18 (females)
0.15-0.8
0.01-0.015
3
Osmolarity:
PPN: Maximum of 900 milliosmoles / liter
TPN: as nutrient dense as necessary (>900
m.osmol and up as high as 3000).
Amino acids (10 m.osmol/gm), dextrose (5
m.osmol/gm) and electrolytes (2 m.osmol
/mEq) contribute most to the osmolarity, while
lipids give 1.5 m.osmol/gm.
Application:
The Solution
Manually mixed in hospital pharmacy or
nutrition-mixing service,
premixed solutions,
Separate administration for every element
alone in a separate line.
Application:
Venous access
PPN: (<900 m.osmol/L): a peripheral line can be
enough.
TPN: Central venous access is fundamental,
Ideally, the venous line should he used
exclusively 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)
Once the correct position of the catheter has been
established (usually by X ray), the infusion can
begin.
Application:
Initiation of Therapy
TPN infusion is usually initiated at a rate of 25 to 50
mL/h. This rate is then increased by 25 mL/h until the
predetermined final rate is achieved.
Administration
To ensure that the solution is administered at a
continuous rate, an infusion pump is utilized to
administer the solution. In hospitalized patients,
infusion usually occurs over 22-24 h/day. In
ambulatory home patients, administration usually
occurs overnight (12-16 h).
Monitoring
Policy: to monitor:
1- Effecacy: electrolytes (S. Na, K, Ca, Mg, Cl,
Ph), acid-base, Bl. Sugar, body weight, Hb.
2- Complications: ALT, AST, Bil, BUN, total
proteins and fractions.
3- General: Input- Output chart.
4- Detection of infection:
Clinical (activity, temp, symptoms)
WBC count (total & differential)
Cultures
Monitoring
Monitoring
Complications of TPN
Sepsis
Pneumothorax
Air embolism
Clotted catheter line
Catheter displacement
Fluid overload
Hyperglycemia
Rebound Hypoglycemia
Complications of TPN
Catheter-related complications
o Catheter sepsis: which can be localized or systemic
(skin portal, malnutrion, poor immunity).
ccc by: fever, chills, ±drainage around the catheter
entrance site, Leukocytosis, +ve cultures (blood &
catheter tip).
ttt:1- exclusion of other causes of fever
2- short course of anti-bacterial and antifungal
therapy (acc. to C&S)
3- Catheter removal may be required
Complications of TPN
Catheter sepsis (Cont.):
Prevention: a rigorous program of catheter care:
 Only i.v. nutrition solutions are administered through
the catheter, no blood may be withdrawn from the
catheter.
 Catheter disinfection and redressing 2 to 3 times
weekly.
 The entrance site is inspected for signs of infection
and if present, culture is taken or the catheter is
removed.
 Other catheter-related complications:
Thromboembolism, pneumothorax, vein or artery
perforation, and superior vena cava thrombosis
Complications of TPN
 Metabolic Complications
o Hyperglycemia (an elevated blood sugar):
Associated with the infusion of excess glucose in the
feeding solution or the diabetic-like state in the
patient associated with many critical illnesses.
It can result in an osmotic diuresis (abnormal loss
of fluid via the kidney), dehydration, and
hyperosmolar coma.
ttt: decrease the amount of infused glucose (to<4
mg/kg/min) OR insulin can be administered (either
S.C. inj. or incorporation in the infusion bag).
Complications of TPN
Metabolic Complications
o Hypertriglyceridemia (High S. Triglycerides)
Associated with excess infusion of fat emulsion.
N.B. Infusion of both glucose and fat emulsion in
excess may result in pulmonary insufficiency.
Excess glucose infusion –> excess carbon
dioxide (CO2) production a result of glucose
metabolism.
Excess lipid infusion --> the lipid particles may
accumulate in the lungs and reduce the
diffusion capacity of respiratory gases.
Complications of TPN
Metabolic Complications
o liver toxicity (also know as parenteral nutrition
cholestasis): It causes severe cholestatic jaundice,
elevation of transaminases, and may lead to
irreversible liver damage and cirrhosis.
Multiple causes have been proposed, including high
infusion rates of aromatic amino acids, high proportion
of energy intake from glucose, e.t.c..
There is no specific treatment, other than anticholestatic
therapy.
Complications of TPN
Metabolic Complications
o Intestinal bacterial translocation:
The lack of direct provision of nutrients to the intestinal
epithelia during total parenteral nutrition Trophism and
altered permeability of the GI mucosa, thus compromising
any potential recovery of the patient’s ability for enteral
feeding, and allowing bacterial entery to blood stream 
sepsis
Prevention is to provide a minimal enteral nutrition supply to
avoid or minimize this risk.
Complications of TPN
Metabolic Complications
o Other metabolic complications:
Electrolyte imbalance, mineral imbalance, acid-base
imbalance, toxicity of contaminants of the parenteral
solution.
Complications of TPN
Mechanical Complications
Catheters and tubing may become clotted or twist and
obstruct.
Pumps may also fail or operate improperly.
HOME PARENTERAL NUTRITION
Patients who are unable to eat and absorb adequate
nutrients for maintenance over the long term may be
candidates for home parenteral nutrition e.g. extensive
Crohn's disease, mesenteric infarction, or severe
abdominal trauma.
patients must be able to master the techniques
associated with this support system, be motivated,
and have adequate social support at home.
HOME PARENTERAL NUTRITION
A patient who is judged to be a candidate for
home parenteral nutrition requires an indwelling
Silastic catheter designed for long-term
permanent use.
The nutrient solutions are prepared weekly and
delivered to the patient's home.
The patient sets up the infusion system and
attaches the catheter to the delivery tubing in
the evening for infusion over the next 12-16 h.
The intravenous nutrition is terminated by the
patient the next morning.
‫سى أَنْ َي ْه ِد َينِي َر ِّبي لَ ْق َر َ ِننْ ذ ََار َر َ‬
‫ددر“‬
‫” َوقُلْ َع َ‬
Among the indications for parentral nutrition
Short bowl syndrome, T
Surgical GIT resection followed by more than 5
days fasting in a cachectic patient, T
Polytrauma, F
Intractable malabsorption, T
Prolonged mechanical ventilation F
For energy requirements
hospitalized adults require approximately 25-30
kcal/kg/day T
A single measurement of energy expenditure by
indirect calorimetry will provide a reliable
estimate of average requirements. F
The most common source of parenteral energy
supply is glucose. T
Glucose in 5% solution can be safely
administered via a peripheral vein, T
With severe infection or injury, basal metabolic
rate rises about 25% above normal F
Regarding Nitrogen balance
A 70 Kgs normal adult male requires about 60
gms of protein daily T
Stress induces catabolic state and hence, a
positive Nitrogen balance F
Special amino acid solutions containing higher
levels of branched-chain amino acids (valine,
leucine and isoleucine) are useful in the
management of liver diseases. T
With renal failure, reduction of the amino acid
load is recommended. T
Glutamine is essential for gut function. F
During Monitoring of TPN
Hyperglycemia can be tolerated so long as
there is no ketosis F
New-onset glucose intolerance in patients
receiving TPN may represent an early sign of
sepsis. T
Serum levels of electrolytes including
magnesium and phosphorus should be checked
daily until stabilized, then two times daily. F
Overfeeding the patients markedly increases
metabolic and respiratory complications. T
Indirect calorimetry is very useful in
mechanically ventilated patients with an FiO
Complications of parentral nutrition
The most frequent catheter-related complication is
SVC thrombosis F
Catheter sepsis is characterized by the classic signs
of infection: chills, fever, and white blood cell count is
usually elevated T
Hyperglycemia is a very serious, relatively common,
problem T
Excessive infusion of aromatic amino acids, glucose,
and lipids may lead to the development of liver
toxicity (cholestasis). T
Excess glucose infusion leads to excess O2
consumption, while with lipid infusion, the lipid
particles may accumulate in the lungs and reduce
the diffusion capacity of respiratory gases. F