Week 7- Parental nutrition

Question 1

what is malnutirion?

Answer 1

A deficiency or excess (or imbalance) of energy,
protein & other nutrients that causes measurable
adverse effects on the tissue/body size, shape,
composition & function & clinical outcome’

Question 2

what are the consequences of malnutrition?

Answer 2

◼ Impaired immunity
◼ Decreased wound healing
◼ Increased complications
◼ Poor response to medical or surgical
therapy
◼ Reduced growth or development of infant or
child
◼ Death!

Question 3

what is parenteral nutrio?

Answer 3

 Intravenous administration of nutritionally
balanced, physiochemical stable & sterile
combination of:
◼ Water
◼ Amino acids
◼ Glucose
◼ Lipids
◼ Vitamins
◼ Trace elements
◼ Electrolytes
 Can fulfil the total nutritional requirements or
can supplement an enteral feed or diet

Question 4

what are the reasons for PN?

Answer 4

 Short-term (inpatient)
◼ Post surgery if patient
NBM (gut rest) > 7
days
◼ Obstruction in gut
◼ Severe shock or gut
infection
◼ Malnourished or unable to eat
 Long-term (home PN)
◼ Non-functioning gut
◼ Not enough gut to function e.g. surgery
 Some patients can eat small amounts
 May or may not be permanent

Question 5

WHAT IS A PATIENTS MAINTENCE FLUID?

Answer 5

Maintenance fluid = 1500ml + (20ml x each

kg of weight > 20kg)

Question 6

what are some factors that would affet their fluid requirments?

Answer 6

 Dehydration
 Fever
 Acute anabolic state
 High temperature
 Low humidity
 G.I. losses
 Burns/wounds
 Blood loss
 Fluid overload
 High humidity
 Blood transfusion
 Drugs
 Cardiac failure
 Renal failure

Question 7

within protein how many amino acid are needed for protein synthesis and how many cannot be syntheised?

Answer 7

20 required for protein synthesis & metabolism
◼ 8 essential – cannot be synthesised
◼ 5 ‘conditionally essential’
 Patient’s needs exceed the synthesis in clinically
stressed conditions

Question 8

what is the adults maintenance calculation for energy a day?

Answer 8

-Majority of adults maintained on 25-35 nonprotein kcal/kg/day

Question 9

what are the 2 types of sources of enegry iN PN?

Answer 9

glucose recommended source for carbs

lipids

Question 10

why is glucose not used along for energy?

Answer 10

 Glucose should NOT be used ALONE
as the energy source because:
◼ Risk of hyperglycaemia
◼ Fatty infiltration of liver (as excess glucose
is converted to fatty acids)
◼ Excessive CO2 production
◼ Excessive consumption of oxygen
◼ Essential fatty acid deficiency

Question 11

how much lipid does a patient need for enegry a day?

Answer 11

Patients typically receive 2.5g

lipid/kg/day

Question 12

what are the advantages of lipid emulsion for energy?

Answer 12

 Large amount of energy in small amount of fluid
 Allows peripheral administration
◼ Isotonic
◼ Venoprotective effect
 Contains some fat-soluble vitamins (E and K)
 Prevents/reverses essential fatty acid deficiency

Question 13

what are the factors affecting micronutrients requirements?

Answer 13

-amount of trace element and vitamins
- Baseline nutritional state on starting PN
◼ Acute or chronic onset of illness
◼ Dietary history
◼ Duration & severity of inadequate nutritional intake
 Increased loss:
◼ Small bowel fistulae/aspirate – rich in zinc
◼ Biliary fluid loss – rich in copper
◼ Burn fluid loss – rich in zinc, copper, selenium
 Increased requirement:
◼ Increased metabolism
◼ Active growth
 Organ function
◼ Liver failure – copper & manganese clearance
reduced
◼ Renal failure – aluminium, chromium, zinc &
nickel clearance reduced

Question 14

what is the summary of the bags contents of a PN?

Answer 14

 Amino acids (► Nitrogen/protein)
 Glucose + Lipids (► Energy + fluid)
 Trace elements
 Vitamins
 Electolytes

Question 15

WHAT IS THE IMPORTANT INFORMATION ABUT PERIPHERAL ADMINISTRATION?

Answer 15

 Considered first-line for parenteral feeding
 Need good line care & low tonicity feeds
 Patients can be successfully maintained for many
weeks
 Can be complicated by phlebitis
 Peripheral solutions have an osmolarity of
approximately 800mOsmol/L
◼ Infused slowly into a large blood vessel with good blood
flow
 Indications
◼ Duration likely to be short-term
◼ Supplemental feeding
◼ Compromised access to central circulation
◼ No immediate facilities to insert central catheter
◼ High risk of fungal or bacterial sepsis
◼ Contraindication to central venous catherisation
 Contra-indications
◼ Inaccessible peripheral veins
◼ High osmolarity of the PN formulation
 High calorie/nitrogen requirements

Question 16

WHAT IS A SCRATCH BAG?

Answer 16

when a patient has needs higher than the normal so need more stuff made from scrtah

Question 17

what is the key infor for central aministeration?

Answer 17

 Indicated when:
◼ Longer-term feeding is anticipated
◼ Peripheral route is inaccessible
◼ High tonicity formulations are required
 Central solutions have an osmolarity of
approximately 2000mOsmol/L
 Solution is rapidly diluted into a central vein
 Inserted into either jugular or subclavian vein
 Position confirmed by x-ray
 Invasive & costly
- Always administered under control of
infusion pumps via a giving set
◼ Avoids overload of fluid, nutrition & electrolytes
 Should be administered at room
temperature
◼ Remove from refrigerator 3 hours before
connection

Question 18

what are the pharmaceutical issues for PN?

Answer 18

 Complex preparations
◼ Contain over 50 chemical entities
 Stability advice from manufacturers & third
party experts
 Issues
◼ Physical stability
◼ Chemical stability
◼ Microbial stability
 Visual inspection before release &
administration to the patient

Question 19

WHAT CAN BE A PHYSICAL STABILITY PROBLEM?

Answer 19

 Precipitation
◼ Potential to infuse solid particles – fatal emboli
◼ Prescribed nutrients may not be infused
◼ Cannot be seen if bag contains lipid
 Lipid destabilization
◼ Lipid globules may come together & coalesce
◼ Occlude the lung microvasculature – respiratory &
circulatory blockages
 All PN fluids are passed through a filter when
infused into patient

Question 20

WHAT CAN BE A PHYSICAL chemical PROBLEM?

Answer 20

 Vitamins
◼ Readily undergo chemical degradation
◼ Often define the shelf-life of the formulation
◼ Vitamin C is least stable - used as a
marker for vitamin degradation
 All bags are protected from light during
storage & infusion

Question 21

WHAT CAN BE A PHYSICAL chemical PROBLEM?

Answer 21

 Highly nutritious medium – potential for
microbial growth
 Manipulations performed using validated
aseptic techniques
 Staff are trained in aseptic technique when
connecting & disconnecting infusions

Question 22

what is the nutritional assessment for needing PN?

Answer 22

 Does the patient need nutritional intervention?
 What are their nutritional requirements?
 How long will the underlying disease last?
 Can the enteral route be used?
 What are the routes PN can be administered?

Question 23

WHAT ARE THE MONITORING PARAMETERS FOR pn?

Answer 23

 Clinical symptoms
 Temperature
 Blood pressure
 Fluid balance
 Weight, anthropometry
 Nitrogen balance
 Lipid tolerance
 Acid-base profile
 Liver function tests
◼ Abnormalities common
 Electrolyte profile
 Blood glucose
 Haematology, CRP
 Calcium, albumin

Question 24

what are some complications for PN?

Answer 24

 Line blockage
◼ Can be caused by:
 Fibrin sheath forming around the line or a
thrombosis blocking the tip
 Internal blockage of lipid, blood clot or salt &
drug precipitates
 Line kinking
 Blockage of a protective line filter
 Line sepsis
 Thrombophlebitis
 Refeeding syndrome
◼ A metabolic complication occurring when the
infused nutrition exceeds the tolerance of a
previously malnourished patient
◼ Start feeding slowly i.e. one bag over 48 hours
instead of 24 hours
◼ Add thiamine if at risk
◼ Can cause significant mortality or morbidity
◼ Characterised by generalised fluid and electrolyte
imbalance in patients with a history of severe weight
loss or chronic starvation

Question 25

WHAT DOES nice say for pn?

Answer 25

 Nutrition Support in Adults
 Consider PN in those who are malnourished or at
risk of malnutrition & either have:
◼ inadequate or unsafe oral and/or enteral nutritional
intake
◼ a non-functional, inaccessible or perforated (leaking)
gastrointestinal tract
 Introduce PN progressively & monitor closely
◼ No more then 50% of estimated needs for 1st 24-48
hours
 Stop PN when adequate oral and/or enteral
support is established