Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

aa 442 > lecture 4 > Flashcards

lecture 4 Flashcards

1
Q

Parenteral Nutrition (PN)

A

Advanced form of MNT
– Prescribing PN independently is not an entry-level competency
– Entry-level competencies (ICDEP)
• Calculate PN regimen requirements (ICDEP, 3.02q)
• Design PN feeding regimens (ICDEP, 3.02r)
• Identify necessary changes to nutrition care plans (3.04c)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

PN: “Ingredients”

A

1.Protein
2.CHO- Dextrose
3.Fat (lipid emulsions)
4.Electrolyte
5.Multivitamin
6.Trace Elements
Extras: medication, ex. insulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Indications for parenteral nutrition

A

• A form of nutrition therapy for those:

  1. Non-functional GI Tract
  2. Unable to meet nutritional requirement via po and/or EN
  3. Inadequate PO and/or EN or NPO status for prolongued period i.e. 5-7 days

• Can be used to provide all requirements or “top-up”
– Total parenteral nutrition (TPN)
– Supplemental PN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Non-Functional GI Tract

A 
• Significant	malabsorption
– i.e.	Short	bowel	syndrome,	
persistent	diarrhea
• Bowel	obstruction
• Prolonged	ileus
• GI	ischemia
• Intractable	vomiting
– Hyperemesis	gravidarum
• GI	fistula
• GI	bleed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Populations PN Commonly Used

A 
Acute	exacerbations	of	Crohn’s
• GI	fistulas
• Short	bowel	syndrome
• Acute	pancreatitis
• Critically	ill
• Cancer	patients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Contraindications to PN

A
  1. Functioning GI tract- if it works, use it
  2. Anticipated Duration/need less than 7 days- not always obvious
  3. Prognosis in which goals of care do not warrant agressive nutrition support
    - not a black and white scenario, for example people with more than 3 months to live
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Routes of PN Infusion

A 
• Central	(CPN)
– Infused	through	a	
large	diameter	vein
• Subclavian,	internal	
jugular

• Peripheral
– Infused through a
small diameter vein
• Anticubital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

CPN (central vs. peripheral) vs PPN Choice Dependent Upon

A
  1. aNTICIPATED DURATION OF THERAPY
  2. Osmolarity
  3. Energy requirement
  4. Fluid Tolerance
  5. Cnetral line contraindication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

PPN (peripheral parenteral nutrition)- Indications

A

Short-term periods of PN
– Up to 14 days

  • Patient reasonably nourished
  • Have peripheral vein access (sometimes malnourished patients have bad vein access)

• Catheterization of a central vein is
contraindicated or not possible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

PPN - Contraindications

Maximum solution osmolarity =

A

• Large calorie, nutrient or electrolyte needs (can cause blood clots, inflammation, infection- irritates vein)
– Maximum solution osmolarity = _900mOsm/L__________
• Fluid restriction (would need the soluation to be more concentrated)
• Need for prolonged PN (>2 weeks)
• Renal or liver compromise
• Severe metabolic stress
• Poor peripheral vein access

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

PPN - Complications

A 
• Phlebitis
– Inflammation	of	a	
vein (caused by concentrated solution, too loong of a period)
• Thrombosis
• Pain
• Infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

PPN – Advantages vs Central PN

A

• Venous access “relatively” easy vs central line insertion
• Decreased complications and infectious risk associated with
central lines
• BUT… IV sites usually changed often to maintain patency of the
vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Central PN: Sites for Access

A 
PN	delivered	to	a	large-diameter	vein
– i.e.	superior	vena	cava	adjacent	to	right	
atrium	
• Several	different	types	of	catheters
– PICC	(peripherally	inserted	central	
catheter)
– CVC	(central	venous	catheter)
– Tunnelled
– Implantable	ports
– See	RQHR	Table	4.1	p.70	&	Chapter	5	
Nelms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Indications for Central PN (vs PPN)

A

• Requiring PN > 14 days
• Can accommodate a hyperosmolar solution
– Required to provide adequate nutrition
– The central vein can tolerate a hypertonic solution because the high
blood flow and volume of blood present rapidly dilutes the
hypertonic solution so that it doesn’t damage the blood vessel.
• Easier to maintain than peripheral access

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Macronutrient Components of PN: Protein

A

• Protein: essential for anabolic processes
– Nitrogen balance must be maintained to minimize breakdown of protein for
gluconeogenesis
• Form in PN:
– Cyrstalline amino acids (essential and non-essential)
• Commercially available concentrations range from 3.5 - 20%
– Several different products (Nelms Table 5.5)
– TravasolTM (3.5%, 4.25%, 5.5%, 8.5%, 10%)
– i.e. 5.5% = 55 g protein per 1 L solution
• 4 kcal/g protein when oxidized for energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Macronutrient Components of PN: Protein

A

• Protein: essential for anabolic processes
– Nitrogen balance must be maintained to minimize breakdown of protein for
gluconeogenesis
• Form in PN:
– Cyrstalline amino acids (essential and non-essential)
• Commercially available concentrations range from 3.5 - 20%
– Several different products (Nelms Table 5.5)
– TravasolTM (3.5%, 4.25%, 5.5%, 8.5%, 10%)
– i.e. 5.5% = 55 g protein per 1 L solution
• 4 kcal/g protein when oxidized for energy

• Amino acid products typically assumed to be 16% nitrogen
– 1 g Nitrogen = 6.25_________
• Useful when determining nitrogen balance in some clinical
scenarios
– Nitrogen balance = (protein intake g/d ÷ 6.25) - (UUN g/d + 4 g/d)
• UUN = urinary urea nitrogen
• Requires 24h urine collection

17
Q

Macronutrient Components of PN: Carbohydrate

A

• Primary source of energy
• Dextrose monohydrate: 3.4______ kcal/g
• Available concentrations: 2.5% – 70%
– i.e. 10% solution = 100 g CHO per 1L solution
– Maximum concentration for PPN: 10% dextrose
• > 10% delivered peripherally will result in thrombophlebitis

18
Q

Macronutrient Components of PN: Carbohydrate

A

• Maximum oxidative rate: 4-5______ mg/kg/min
– Excessive administration:
• Hyperglycemia
• Hepatic abnormalities (i.e. fatty liver, cholestasis)
• Excess CO2 production / ventilatory drive
• Overfeeding
• Minimum (amount of CHO) required for protein sparing (not to degrade muscles): 1____ mg/kg/min

19
Q

Macronutrient Components of PN: Lipid

A

• Dual role of lipid
– Source of (non-protein) energy (1 g lipid = 9 kcal)
– Source of essential fatty acids (prevent EFA deficiency)
• Linoleic & alpha-linolenic
• PN lipid emulsions available in following concentrations:
– 10% (1.1 kcal/mL)
– 20% (2.0 kcal/mL)
– 30% (3.0 kcal/mL)

20
Q

Different types of lipid emulsions

A 
1st generation
– IntralipidTM
• Soybean	oil	
• Egg	yolk	phospholipid	(emulsifier)
• Glycerol	(ensures	emulsion	in	isotonic)
– High	in	n-6	fatty	acids
• Pro-inflammatory
• Associated	with	hypertrigylceridemia,	liver	disease	etc.	
• 2nd generation
– Balanced	blends	of	n-3,	n-6,	n-9	PUFA’s
• LCT	+	MCT	mixtures
• Fish	oil	emulsions
• Olive	oil	based	lipid	emulsions
– Anti-inflammatory	properties
– Associated	with:
• Reduced	PN-associated	liver	disease
• Improved	outcomes	septic	patients
22/11/17
9
Glucose 10-40%
Na, K, Ca, P
Amino acids
Na, K, Mg
Lipid emulsions
Trace elements
Vitamins
Modern PN – All-in-One Admixtures
No significant differences
Apparent
insignificant
differences
Special solutions
(glutamine)
- many types of emulsions
(LCT, MCT/ LCT, omega-3-
FA, structured)
- Special solutions (omega-3-
FA)
No major
differences
Minor differences
(iron, manganese)
Lipid emulsions
nowadays
Long - chain triglycerides (LCT)
LCT+MCT mixtures
Fish oil emulsions
Olive oil based lipid emulsions
SMOF-emulsion
Basics in clinical nutrition, ESPEN 2004.
Fürst P. J. Nutr. 128: 789-796, 1998.
Wirtitsch M. Et al
21
Q

2nd Generation Lipid Emulsions: SHR

A 
• ClinOleic®
–20%	soybean	oil
–80%	olive	oil
• SMOFlipid®
–30%	soybean	oil	(S)
–30%MCT	(M)
–25%	olive	oil	(O)
–15%	fish	oil	(F)
22
Q
  • Minimum amount of fat to prevent EFA deficiency

* Typical adult dosing:

A

8-10% of energy requirements
– 500 mL Intralipid® weekly
• Hypertriglyceridemia à restrict amount
• Typical adult dosing:
– 25-30% of energy requirements
– Maximum 1-1.5_____ g/kg/d non-ICU patients; ICU patients 1______ g/kg/d
– Infusion rate should not exceed 0.11_____ g/kg/h

23
Q

Nutrient Admixtures

A

• 3-in-1 / Total Nutrient Admixture (TNA) solution
– Incorporates all PN components (aa, dextrose, lipid, electrolytes,
vitamins, trace elements) in form of an emulsion
• 2-in-1 solution
– Incorporate all constituents except lipids (can be hung separately)

24
Q

PN Additives

A

• Additives – Electrolytes – Vitamins – Trace Elements • American Medical Association originally released recommendations for vitamins and trace elements (1979) – ASPEN recommended modifications in 2012 • Refer to SHR order sets & RQHR handbook • Adjusting doses is NOT entry level – Restricted activity

25
Q

PN Additives: Electrolytes

A

• Standard daily electrolyte requirements – Sufficient for most patients – Needs change based on condition • Disease state (i.e. renal failure) • Excess losses (diarrhea, vomiting, fistula, ostomy) • Refeeding syndrome, etc.

3-in-1 Adult Parenteral Nutrition Orders
Order Writing
- A daily order is required for the first seven days of therapy and, at a minimum, a once weekly order is
required after day 7 (e.g. day 1, 2, 3, 4, 5, 6, 7, 14, 21 etc.)
- When new orders are written, the previous order will be discontinued.
Daily Electrolyte Additions*
To prevent stability and compatibility problems, electrolyte additions cannot exceed established limits.
Pharmacy will prepare parenteral nutrition with the maximum safe amounts possible. Any changes will be
documented in the health record and prescri

26
Q

PN Additives: Vitamins

A

Standard PN preparations contain recommended IV doses of

fat and water soluble vitamins

27
Q

Fluid Considerations

A

• Requirements based on conditions
– Estimated using various formulas (RQHR handbook)
– Increased
• Increased renal, GI, dermal, respiratory losses
– Decreased
• Cardiac or renal insufficiency
• When doing nutrition assessment, fluid intake from all sources
must be considered

aa 442 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions