Parenteral Nutrition

Question 1

A sterile intravenous solution of essential nutrients bypassing the digestive/absorptive system, because the GI tract is not functioning or cannot be used.

Answer 1

Parental Nutrition

Question 2

1. GI tract inaccessible or unsafe for EN
2. Non-functioning GI tract
3. Bowel rest

Answer 2

Indications for PN use

Question 3

2-in-1 Formulation Includes?

Answer 3

Protein and Dextrose

Question 4

3-in-1 Formulation Includes?

Answer 4

Protein, Dextrose, and Intravenous Fat Emulsions (IVFE)

Question 5

Components of PN

Answer 5

Amino Acids
Carbohydrate (dextrose)
Fat (lipid emulsion)
Vitamins
Minerals
Electrolytes
Fluid
AA, CHO, and electrolytes contribute to increased concentration or osmolarity

Question 6

Synthetic Crystalline AA

Answer 6

4 kcals/g

Biologically utilizable for protein synthesis

Question 7

Dextrose

Answer 7

Primary source of CHO in PN.
50% (D50)
70% (D70) - most common
Yields 3.4 kcals/g
CHO content should not exceed 7 g/kg/day

Question 8

Emulsified Lipid Particles

Answer 8

Contains:
Egg yolk phospholipid as an emulsifier that prevents separation.
Soybean or safflower oil
Water
Glycerol- makes emulsion isotonic or bland
Most common concentration is 20% (2 kcals/ml)

Question 9

Essential Fatty Acid Deficiency (EFAD)

Answer 9

Lipid or IVFE prevents EFAD.
2-4% linoleic and 0.25-0.5% of alpha linoleic needed for prevention.
EFAD can develop after 4 weeks of fat-free PN.
Topical EFA application has been shown to be effective in preventing EFAD, but not curing it.

Question 10

Intralipid, Omegaven, SMOF

Answer 10

Types of IV lipids. Fat content of PN formulation should not exceed 30% of total daily kcals.

Question 11

Vitamins

Answer 11

Available as injectable multivitamin (MVI) infusions. 10 mL daily should be added to PN.

Question 12

Chromium, Copper, Manganese, Selenium, Zinc, and Iron (as Iron Dextran) are what?

Answer 12

Multiple Trace Elements (MTE). Individual trace elements can be added if serum levels are low. 3 mL dose unless concentrate then 1 mL dose.

Question 13

Iron Dextran

Answer 13

Test dose must first be administered to rule out an allergic reaction to IV iron. Can be added to PN. Does not come in standard MTE. Iron cannot be added to lipid-base PN because it destabilizes the formula.

Question 14

Calcium Gluconate, Magnesium Sulfate, Phosphate, Potassium, and Sodium are?

Answer 14

Electrolytes

Question 15

Potassium

Answer 15

Key to nerve impulse transmission and muscle contraction. Abnormalities can be mild to life-threatening.

Question 16

Phosphorus

Answer 16

Shifts into cell during anabolism (refeeding syndrome). PN should not be started when PO4 levels are very low (<2.0)

Question 17

Magnesium

Answer 17

Shifts into cell during anabolism.

Question 18

Calcium

Answer 18

60% bound to albumin. Ionized Ca level more accurate. Corrected Ca formula is a way to get correct Ca levels.

Question 19

Chloride

Answer 19

Helps maintain osmotic pressure, acid-base balance.

Question 20

Acetate

Answer 20

Helps maintain acid-base balance.

Question 21

Fluid

Answer 21

All substances added to PN require a minimum amount of fluid to allow mixture to be compatible.

Question 22

Peripheral IV

Answer 22

Tip in vein of hand or arm. Short-term, 5 days to 2 weeks.

Question 23

Central IV

Answer 23

Tip in mid to lower Superior Vena Cava by the heart. Long-term therapy >2 weeks.

Question 24

Peripheral IV Catheter

Answer 24

An IV inserted into the arm or hand where the tip stops in the arm or hand.

Question 25

Peripherally Inserted Central Catheter (PICC)

Answer 25

Used for PN administration if the anticipated length is 4-6 weeks.

Question 26

Hickman

Answer 26

Tunneled catheter; most appropriate for long-term therapy outside of the acute care setting (4 weeks-years).

Question 27

Mediport

Answer 27

Usually used for chemotherapy but occasionally can be used for long-term PN.

Question 28

Central Venous Catheter (CVC)

Answer 28

Temporary non-tunneled central IV for short-term ON use, placed in the subclavian or jugular vein.

Question 29

Femoral Catheter

Answer 29

Associated with a higher risk of venous thrombosis and catheter related sepsis; they are not recommended for PN administration unless no other venous access can be attained.

Question 30

Compatible PN Formula

Answer 30

Is one that does not develop the formation of precipitates.

Question 31

Precipitates

Answer 31

Come from the additives that react with one another which can cause harm to the patient. Macro-precipitates exceeding 5 microns and pass into the central circulation can cause a blockage.

Question 32

1.2 Micron Filter

Answer 32

Eliminates or reduces infusion of particulates, mino precipitates, microorganisms, pyrogens, and air.

Question 33

Liquid Precipitates

Answer 33

Separation of oil (lipid) and water as in a 3-to-1 formulation.

Question 34

Solid Precipitates

Answer 34

Incompatible combination of various salts added to PN resulting in the formulation of an insoluble product.

Question 35

Compatibility of PN Using Lipids

Answer 35

Formulas containing lipids are destabilized by numerous cations such as calcium, magnesium, sodium, potassium,, that are added to PN. This increases the risk of lipid droplet separation.

Question 36

Compatible Medications for PN

Answer 36

Regular Insulin
Famotidine (Pepcid)
Metoclopramide (Reglan)
Octreotide
Corticosteroids
Heparin

Question 37

Complications of PN

Answer 37

Hyperglycemia/Hypoglycemia
Catheter-related blood stream infection
PN-associated liver disease

Question 38

Hyperglycemia and PN

Answer 38

Causes: Dextrose in Pn
Treatment: Add regular insulin to PN. Decrease dextrose kcals. Before advancing dextrose kcals, ensure blood glucose is <200 mg/dL.

Question 39

Hypoglycemia and PN

Answer 39

Causes: PN is suddenly stopped or too much insulin in PN.
Treatment: Give juice if able to take oral diet. Give IV dextrose 50% if cannot take oral diet. Stop PN if too much insulin and give IVF with dextrose.

Question 40

Catheter-Related Blood Stream Infection

Answer 40

Common Organisms: Staphylococcus aureus, pseudomonas, enterococcus, and yeast.
Causes: Migration of skin flora at insertion site. Hub site. Seeded from remote source (abd abscess, wound, etc). Contaminated solution (rare).

Question 41

Non-Infectious Catheter-Related Complications

Answer 41

Catheter Occlusion
Catheter Breakage
Catheter Dislodgement

Question 42

PN Associated Liver Disease

Answer 42

Causes: Over-feeding (dextrose, fat, total kcals). Soy-based IVFE. Continuous infusion of PN.
Treatment: Decrease total kcals. Limit or stop IVFE. Cycle PN.

Question 43

Continuous Infusion

Answer 43

24hr continuous infusion. Usually used solely in hospital setting. Always used for Peripheral PN (PPN), but can be used for Central PN (CPN). PN is always started at a 24 hr infusion.

Question 44

Cycled

Answer 44

8-16 hrs. Usually when a pt is being discharged from the hospital to home or another facility. Only used in Central PN.

Question 45

Transitional Feedings

Answer 45

The process of weaning a pt off of PN to EN or oral diet. PN should not be discontinued until the pt is tolerating >50% of energy and protein needs from either TF or oral diet.

Question 46

Transitioning Off of PN in the Hospital

Answer 46

Taper calories and protein down by approximately half. Decrease PN volume based on TF volume or oral intake. Decrease hourly PN rate by half during the last hour of PN to prevent hyperglycemia.

Question 47

Transitioning Off of PN at Home

Answer 47

Decrease infusion days from 7 days per week to 3-4 days. Check lab work the following week. If labs are ok, continue to decrease infusion days or stop PN. Have central catheter removed if ok to stop.