ICM - Viva - Nutrition

Question 1

What % of patients are malnourished on arrival to ICU

Answer 1

50%

Question 2

Problems with malnutrition in ICU

Answer 2

Altered immunity - susceptible to infection

Prolonged MV

Increased LOS

Question 3

How to assess nutritional status of patients

Answer 3

Clinical - weight and weight loss (recent)
           Co-morbid illnesses
           Severity of illness
           Evidence of GI dysfunction
           MUST scoring
           Upper arm circumf

Lab - anthropometry and albumin, confounded by oedema and acute phase changes

Question 4

Ways to calculate energy needs

Answer 4

Indirect Calorimetry

Eqns - Harris-Benedict and Scholfied

Estimate based on IBW at 25-30kcal/kg/day (and add 20% in obesity)

Question 5

Evidence on energy calculation strategy for feeding

Answer 5

TIACOS - targeted energy based on indirect calorimetry

(Vs 25kcal/kg/day)

Calorimetry received more calories, increased MV and LOS
Trend to reduced mort

EDEN trial - Trophic feed (25% of target) for first 6 days changed vent length

Received fewer calories, but outcomes were as good as full feed

Question 6

Protein needs and rationale

Answer 6

Catabolism of protein is rapid.
Protein needs are higher than energy needs, and not met by provision
Open abdo is source of nitrogen loss, estimated at 2g nitrogen/litre fluid

Weight based - 1.2 - 2g/day

Negative N2 balance - excreting more N than taking in —> muscle loss

Balance = (Total protein in / 6.25) - (UUN +4)

Where UUN is nitrogen excreted in urine in 24 hours (+4 is insensible)

Question 7

Calorie split

Answer 7

Of the non protein calories

60% carbs
40% lipid

Question 8

Patients Requirements

Answer 8

Water. 30ml/kg
Sodium 1-2mmol
K 0.8 - 1.2
Ca. 0.1
Mg 0,1
Phos 0.4

Question 9

Routes

Answer 9

Oral
NG
NJ
PN

Enteral is preferential unless a reason not to

Question 10

Advantages of enteral

Answer 10

Physiological
Cheaper
No central line

GI tract integrity maintained - structure, perfusion, motility, less ulcers
Promotes immune function - mucosa assoc lymphoid, IgA

Question 11

Advantages of parenteral

Answer 11

Don’t need a functioning GI tract

Can start early - no delay

Less interruptions

Question 12

Disadvantage of Enteral

Answer 12

Needs a functioning tract
Diarrhoea
Risks with NG

Known to increase VAP risk
NG - sinusitis

Metabolic issues - electrolytes, high BM, refeeding

Question 13

Disadvantages of parenteral

Answer 13

Not physiological

Hyper osmolar and irritant - central access

Systemic infection

Expensive

Hypercholesterolamia

Lipid emulsion - fatty liver

Question 14

Evidence on route of feeding

Answer 14

CALORIES trial

No difference in mortality if fed enterally or parenteral lay

Question 15

How to improve enteral delivery

Answer 15

Prokinetic - erythromicin/metoclop

Post pyloric feed - NJ/Jej

Question 16

When to start feed

Answer 16

Enteral - within 24-48 hours of admission

After initial resus and haemodynamically stable

You don’t need flatus or bowel sounds to start

Question 17

If EN is failing, what do the guidelines suggest

Answer 17

ESPEN - start TPN at 24 hours if EN not tolerated

ASPEN - after 7-10 days if unable to meet 60% of energy by enteral route

Question 18

Evidence for early / late initiation of PN

Answer 18

EPaNIC - day 3 or day 8 PN

Late - increased survival, shorter MV and RRT

Question 19

Components of TPN

Answer 19

Standard formulations

40% is non protein calories as lipid and 60% carbs

Amino acids/vitamins (B1, folate,; fat soluble ADEK)

Trace element (zinc, copper selenium)

Electrolytes

Question 20

Any evidence for Immunomodulation from nutrition supplements

Answer 20

Glutamine
Maybe good in burns and trauma,
Facilitates nitrogen transport and reduce protein loss

REDOX trial - early glutamine in MOF was harmful, higher mortality

Arginine
NO prescursor
Improves macrophage and NK cells cytotoxicity
Harmful in sepsis

Omega 3 - anti-inflammatory
OMEGA trial stopped for futility, less vent free days

Selenium - scavenges oxygen free radicals
Non significant reduction in mortality

Question 21

Any evidence for Glycaemic targets in non diabetic?

Answer 21

NICE-SUGAR
Tight very conventional glucose control (tight 4.5 to 6) (convention less than 10

90 day mortality higher in tight group
More hypos

Previous small studies suggested tight might be better

Question 22

Refeeding pathophysio

Answer 22

Happens when nutrition is restarted in patients have starved

Chronic malnutrition - protein and fat metabolism, and phosphate loss

Reintroduce carbs - anabolic state, insulin surge,
Re uptake of phosphate, magnesium and potassium

Question 23

Effect of carb load in refeeding

Answer 23

Insulin release

Glycogen synthesis , Fat Synth, Protein Synth, (these need K, Mg, PO3)
PO3 uptake into cells

Hypophophate, Mg lost in urine

Form phosphorylated carb compounds —deplete ATP
Cellular dysfunction, decreased o2 delivery

Question 24

Presentation of refeeding

Answer 24

CVS - heart failure and arrhythmia

GI - Vomiting, constipation, anorexia

Resp - resp muscle weakness

MSK - weak, osteomalacia

Neuro - ataxia delirium’s, coma, Wernickes (thiamine)

Metabolic - Low PO, MG, K, Ca, Thiamine

Question 25

Risk factors for Refeeding Sybdrome NICE criteria

Answer 25

One of:
BMI <16.
Weight loss 15% in 3-6/12.
Little intake 10 days.
Low K, PO, Mg before.

Two of
BMI < 18.5
Loss of 10%
5 day Poor intake
Alcohol abuse

Question 26

Comorbidities that are Risk factors for refeeding

Answer 26

Decreased intake - eating disorder, alcohol,depression, NBM,

Decreased absorption - Malabsorption, IBD, CF, panc, short bowel

Increased catab - malignancy, inflammation

Question 27

Tx of refeeding

Answer 27

Monitor and look out for it
Risk assess

Electrolytes, vitamins and trace elements
Pabrinex for 3 days, then thiamine and vit B

Avoid fluid overload

Cautious re-institution of feed 10kcal/kg/day

Question 28

Vitamin A role and deficiency

Answer 28

Vision, growth

Night blindness, Xeropthalmia

Question 29

B1
What is it
Role
Deficiency

Answer 29

Thiamine
Co-enzyme in ATP production

Dry beri beri - wasting and paralysis, damaged nerves
Wet beri berry - high out put cardiac failure
Wernickes - ataxia, confusion, opthalmoplegia
Korsakoff - memory loss

Question 30

B2
What is it
Role
Deficiency

Answer 30

Riboflavin

Red cell production, anti-oxidant

Ariboflavinosis - Stomatitis, sore tongue and throat, fissured lips

Question 31

B3
What is it

Role

Deficiency

Answer 31

Niacin

Skin formation, Metabolism

Pellagra - diarrhoea, dermatitis, dementia

Question 32

What is vitamin B9? needed for? deficiency?

Answer 32

Folate

DNA/RNA production
RBC production

Glossitis, diarrhoea, confusion, anaemia

Foetal neural tube

Question 33

B12

Answer 33

Cobalamin

DNA and RNA
RBC

Pernicious anaemia
Subacute combined degeneration of the cord

Question 34

C

Answer 34

Collagen production, wound healing, teeth and bond maintain acne

Weakness, weight loss,
Scurvy

Question 35

D

Answer 35

Calcium absorption
Immune system

Rickets and osteomalacia

Question 36

Vit E

Answer 36

Anti ox, free radical scavenger

Dysarthria
Loss of tendon reflexes
Ataxia
Anaemia
Retinopathy

Question 37

Vit K

Answer 37

Coag, bone metabolism

Hypercoagulable

Question 38

Selenium

Answer 38

Converts T4 into T3

Hypothyroid
Osteochondropathy (Kasin Beck disease)

Question 39

Zinc deficiency

Answer 39

Hormone production

Diarrhoea
Acne
Motor disorder

Question 40

Role of Copper

Answer 40

Iron transport
Maintain bone, cardiac and connective tissue

Myelopdysplasia,
Anaemia

Question 41

Zinc

Answer 41

Bone production
Skin integrity
BM control

Bone demineralisation
Altered carb/fat metab
Impaired glucose tolerance