Supportive and Palliative Care (Nutrition)

Question 1

Causes of malnutrition

Answer 1

Decrease intake absorption:
- Cancer → loss of appetite, taste changes. N/V
- Dialysis
- Malabsorption due to surgery
- Advanced abdominal cancer and ascites
- Stress: burns, trauma, surgery

Increased expenditure losses

Question 2

Effects of malnutrition

Answer 2

Increased complications
Poor wound healing
Compromised immune status
Impairment of organ functions
Increased mortality
Increased use of healthcare resources

Question 3

What are the four steps done during nutritional screening and assessment

Answer 3

1. Nutritional screening
2. Refer to dietitian/nutritional specialist
3. Nutritional assessment
   An in depth, systemic process that integrates and interpret pt data to identify nutrition-related problems
   A: Anthropometric- height, weight
   B: Biochemicals- electrolytes, albumin (low)
   C: Clinical- Hx, physical exam
   D: Diet
4. Formulation of nutritional regime

Question 4

What is a common nutritional assessment used

Answer 4

Seven-point subejctive global assessment (SGA)

Question 5

What is total energy expenditure dependent on?

Answer 5

resting/basal metabolic rate, physical activity, stress factor

Question 6

What are the 3 modes of measurement for energy?

Answer 6

1. Indirect calorimetry
2. Weight based
3. Predictive equations (schofield and harris-benedict eqn)

Question 7

How does indirect calorimetry measure energy?

Answer 7

Measurement of gas exchange during consumption of substrates to produce required energy

Question 8

How does weight based measurements measure energy

Answer 8

25-35 kcal/kg for general hospitalized patients (ESPEN)

Question 9

What is the disadvantage of using predictive equations to measure energy?

Answer 9

Only estimates basal metabolic rate so need to adjust for activity and stress factor
Lower accuracy than calorimetry but is most commonly used in clinical setting

Question 10

Which mode is the gold standard for measuring energy

Answer 10

Indirect calorimetry but it is tedious so not commonly used

Question 11

What are the protein requirements for different individuals (healthy, CKD pts)

Answer 11

Healthy: 0.8g/kg/day
CKD:
- Not on dialysis: 0.6-0.8g/kg/d
- HD/PD: 1.2g/kg/d -> protein is lost during HD/PD
- CRRT: Up to 2g/kg/d

Question 12

What is enteral nutrition?

Answer 12

“Nutrition provided through the gastrointestinal tract via a tube, catheter, or stoma that delivers nutrients distal to the oral cavity.” - ASPEN

Question 13

What are some examples where enteral nutrition is used?

Answer 13

For patients who are unable to receive/tolerate adequate nutrition by the oral route

Examples:
Swallowing impairment eg. post stroke
Mechanical ventilation eg. have tube for breathing alr
Altered mental status eg. lose consciousness
Motility disorders eg. gastroperesis (diabetes)

Question 14

What are the types of enteral access devices?

Answer 14

Pre-pyloric (NG, PEG)
Post-pyloric (NJ, PEJ)

Question 15

Which enteral access devices is preferred and why?

Answer 15

Pre-pyloric:
- More physiologic: maximise potential of GIT.
- Higher tolerance to bolus feeding
- Higher tolerance to a wide range of enteral products
- May be used for venting

Question 16

When is pre-pyloric devices not used?

Answer 16

Pts with delayed gastric emptying

Question 17

When is post-pyloric devices used and why?

Answer 17

Only used in conditions that result in dysfunctionality in proximal GIT due to high risk of tube clogging

Question 18

What is the advantage of using post-pyloric devices

Answer 18

Smaller bore so less discomfort
Minimize aspiration risk

Question 19

When is stomy tubes used over nasal tubes?

Answer 19

Inserting stomy tube is a small surgical procedure so it is more difficult to insert and remove. The wound may not heal after removing so it is more for pts that need it for lifelong

Question 20

What are the 2 modes of administering enteral feeds and which is better tolerated and why?

Answer 20

Bolus:
Usually by gravity- mimics oral intake
More physiologic
No pump required, just pour
Greater freedom for ambulation

Continuous:
Pump assisted delivery at a constant rate
Better tolerated- Split into smaller meals so less bloated
Lower risk of aspiration

Question 21

What are the 4 types of EN formulas and their compositions?

Answer 21

Modular:
Contains single nutrient
Used as fortifier to enhance a specific nutritional component / augment oral diet
Not meant as meal replacement

(Semi) elemental:
High osmolarity → diarhhoea
Contains partially/ completely hydrolyzed nutrients
For patients with impaired GI function, impaired tolerance to standard feeds

Polymeric:
Contains intact macronutrients eg. complex sugars etc
Requires sufficiently functional GIT

Immune-modulating/disease-specific:
Contains additions / restrictions of specific nutrients to meet needs for disease management
May or may not meet individual’s full nutritional needs

Question 22

Provide some examples for the different types of EN formula

Answer 22

Modular: Myotein, valens enersus
Semi-elemental: peptamen
Polymeric: Ensure, resource fruit, boost
Disease-specific:
- Diabetes: glucerna
- Increased protein: Fresubin
- CKD: Nepro
- Infl. disease/cancer: NutriFriend

Question 23

What is the consequences of drug interactions with EN formulas?

Answer 23

Precipitation
Curdling, clumping of protein
Alteration of dosage form (e.g. sustained/modified release/enteric coated)

Question 24

How to prevent and mitigate drug-nutrient interactions

Answer 24

Stop feeding, flush access device before and after drug administration
Use therapeutic alternatives available in appropriate dosage form

Question 25

What are common complications of enteral feeding

Answer 25

1. Occlusion of feeding tube (if nvr flush properly esp small bore) - Jejunal > gastric tube - Medication administration - Formula – concentrated/high protein/fibre-enriched 2. Tube migration: when pt coughs 3. Infections secondary to microbial contamination 4. Aspiration 5. Nausea/vomiting 6. Diarrhea/Constipation 7. Refeeding syndrome

Question 26

What are some strategies to maximise tolerance to EN

Answer 26

- Continuous instead of bolus - Use of prokinetic agents (e.g. metoclopramide, domperidone, IV erythromycin) - Post-pyloric feeding if intolerant to gastric feeding eg. gastroperesis - Use of isotonic formula (e.g. boost isocal) - Semi-elemental/elemental feeds for patients with malabsorptive issue (e.g. short bowel syndrome)

Question 27

What are some advantages of enteral feeding

Answer 27

- Maintain functional integrity of the gut - Undergo first-pass metabolism, promote efficient nutrient utilization - Maintains normal gallbladder function - Maintain gut-associated and mucosal-associated lymphoid tissues - Less complications than PN – e.g. line related sepsis, IFALD - Less expensive

Question 28

What are some indications for parenteral nutrition?

Answer 28

For patients who are unable to receive or tolerate adequate nutrition by enteral route Examples: - Paralytic ileus: dismotility of intestines - Small bowel obstruction - High output / proximal fistula - Mesenteric ischemia: blood vessel supply to intestine is compromised

Question 29

What are the two types of parenteral access?

Answer 29

Peripheral: Tip position is located outside of central vessels Central: Position of catheter tip is in large bore blood vessel e.g. distal superior vena cava, inferior vena cava, right atrium

Question 30

What are two differences btw the different parenteral accesses

Answer 30

Peripheral: Requires frequent re-site (every 72hrs) Nutrient delivery limited by osmolarity and concentration Central: Can be used for longer term care (dont need re-site so frequently) Blood flow is very high so can give more nutrients in smaller volume

Question 31

4 Examples of central catheters

Answer 31

1. Non-tunnelled central venous catheter - Max 2wks, tube is short so highest risk of infection 2. Tunnelled central venous catheter - Go under skin so lesser infection 3. Peripherally inserted central catheter (PICC) 4. Port-a-cath: For cancer pts on chemo

Question 32

What does parenteral nutrition composed of

Answer 32

Nutrition in its simplest, most elemental form and admixture of multiple components eg. dextrose solution, a.a, electrolytes, lipid emulsion

Question 33

What are some major concerns of parenteral nutrition composition?

Answer 33

Stability and compatibility

Question 34

What are the consequences of drug interactions with PN

Answer 34

Precipitation Loss of drug activity Phase separation of lipid emulsions: cause cracking Toxicity

Question 35

How to prevent and mitigate drug-nutrient interaction with PN

Answer 35

- Administer via separate peripheral IV cannula - If needed, pause PN administration, flush access device before and after drug administration before resuming PN infusion

Question 36

What are some device related complications of PN devices

Answer 36

1. Occlusion in IV catheter - Thrombosis / clotting - Inappropriate flushing techniques - Precipitates as a result of drug incompatibilities, crystallization - Lipid residues 2. Mal-positioning 3. Catheter-related bloodstream infection (CRBSI)

Question 37

What are some metabolic complications of PN

Answer 37

1. Refeeding syndrome 2. Hyper/hypoglycemia 3. Fluid overload 4. Intestinal failure associated liver disease (IFALD) - Associated with prolonged not eating 5. Metabolic bone disease: osteomalacia

Question 38

Pathophysiology of refeeding syndrome

Answer 38

Malnutrition --> body draws electrolytes from intracellular stores and reduces renal excretion --> causes hypoK, hypoMg, hypoP, edema and thiamine deficiency.

Question 39

How to manage refeeding syndrome

Answer 39

1. Identify high risk pts 2. Check serum electrolytes at baseline 3. Correct deficiencies prior to feeding, defer feeding if electrolytes are critically low 4. Administer thiamine (Vit B1) supplement 5. Initiate feeding slowly and gradually increase over next few days to meet nutritional requirements (Start low and go slow!) 6. Continue to monitor electrolytes as feeding progresses, adjust amount of replacements as needed

Question 40

According to NICE guidelines, what is the criteria for high risk patients for refeeding syndrome

Answer 40

One of the following: BMI <16 Unintentional weight loss >15% in past 3-6m Little or no nutritional intake >10d Low K, Mg, P before feeding OR >=2 of the following: BMI <18.5 Unintentional weight loss >10% in past 3-6m Little or no nutritional intake >5d Hx of alcohol misuse or drugs incl insulin, chemotx, antacids or diuretics.

Question 41

What is the activity factor for little or no exercise when calculating energy using predictive equations?

Answer 41

1.2

Question 42

What is the stress factor for cancer when calculating energy using predictive equations?

Answer 42

1.1-1.5