8: Nutrition

Question 1

Over what time scale do you feed a critical patient?

Answer 1

Correct fluids and electrolytes over 24h, then feed on days 2 and 3

Question 2

What three kinds of patients should you feed?

Answer 2

Anorexic for three days, recent weight loss above 10%, catabolic state e.g. burns or sepsis

Question 3

How good is using bloods to estimate nutritional need?

Answer 3

Inaccurate

Question 4

What is BER for cats?

Answer 4

BW x 50 kcals/day

Question 5

What is BER for dogs and cats over 2kg?

Answer 5

BW x 30 + 70 kcals/day

Question 6

What % of the BER do you initially give?

Answer 6

50%, then increase

Question 7

In which situations is this calorie estimate an underestimate?

Answer 7

Long term or catabolic state

Question 8

How often should you weight the animal?

Answer 8

At least once a week, daily if possible

Question 9

Which kind of animals suffer accelerated starvation?

Answer 9

Concurrent injury, infection or neoplasia

Question 10

What ultimately kills the animal in starvation?

Answer 10

Calorie loss causes body protein loss

Question 11

What signs do you see in refeeding syndrome in cats?

Answer 11

Cardiac, respiratory, NM, haematology

Question 12

What is the cause of refeeding syndrome?

Answer 12

Already has low K and P and sudden insulin release causes increased cell uptake

Question 13

How do you prevent refeeding syndrome?

Answer 13

Slowly increased calories and give high protein rather than high carb diet

Question 14

When is the only time you should use appetite stimulants?

Answer 14

If already interested in food

Question 15

What are some examples of appetite stimulants?

Answer 15

Valium, mirtazapine, midazolam

Question 16

How do you feed if they are food-aversive?

Answer 16

Tube feed

Question 17

When should you not use an NG tube?

Answer 17

If oral, pharyngeal, oesophageal or nasal disease

Question 18

What length should an NG tube be?

Answer 18

75% of nose to last rib

Question 19

Where does an NG tube end and why?

Answer 19

Distal oesophagus to avoid acid reflux

Question 20

Which kind of tubes are better tolerated for the long term?

Answer 20

Oesophagostomy or gastrostomy

Question 21

When should you not use an oesophagostomy tube?

Answer 21

In oesophageal disease

Question 22

What is a disadvantage of oesophagostomy tube?

Answer 22

Need GA to place

Question 23

What kind of timescale are gastrostomy tubes used for?

Answer 23

Over 5 days

Question 24

How are gastrostomy tubed usually placed?

Answer 24

Endoscopically

Question 25

What are the next most important factors after fluids and electrolytes?

Answer 25

Energy then protein, minerals and vitamins are last

Question 26

What are two common ways malnutrition can develop in a hospital?

Answer 26

Lack of records, witholding food for GA

Question 27

When does muscle protein loss occur compared to other changed in malnutrition?

Answer 27

Last - already serious by the time they lose muscle mass

Question 28

How long a period of anorexia does it take for stomach capacity to halve?

Answer 28

48 hours, so must introduce tube feeding slowly - and also see reduced gastric tone and emptying

Question 29

What happens to BER in uncomplicated starvation?

Answer 29

Lowers, because reduced insulin reduces the conversion of T4 to active T3

Question 30

In initial starvation, what is the glucose source?

Answer 30

Glycogen - used up within days

Question 31

After about a week, what is the main source of glucose?

Answer 31

Stored fat

Question 32

What is the glucose source in late starvation?

Answer 32

Back to body protein again

Question 33

What diet components do dogs need more of in stress and starvation?

Answer 33

More protein and fat, less CHO

Question 34

Which tissues are obligate glucose users?

Answer 34

RBCs, renal medullary cells, nervous tissue, fibroblasts, some tumours

Question 35

Which are the first body proteins to be used?

Answer 35

Plasma proteins, visceral proteins, muscle

Question 36

Which are the last body proteins to be used?

Answer 36

Bones, ligament, cartialge

Question 37

Which are the proteins lost in the first 2-3 days?

Answer 37

Liver protein - all albumin and fibrinogen

Question 38

What happens to the GI tract when it proteins are used up?

Answer 38

Reduced mass, flattened villi, reduced brush border activity, CHO and fat digestion affected first

Question 39

What are the effects on the immune system when protein is being used up?

Answer 39

Can't make antibodies, reduced lymphocytes, reduced barrier function of skin and mucosa, reduced inflammatory response

Question 40

What are the terminal changes in starvation as protein becomes the primary energy source again?

Answer 40

Very thin SI wall, intercostal and diaphragm muscles fail

Question 41

Why does concurrent injury accelerate starvation?

Answer 41

Stress overrides the BMR down-regulation

Question 42

Why does injury accelerate starvation?

Answer 42

FIbroblasts use all the glucose, increased protein and amino acid requirements for wound healing, proteins are lost in haemorrhage, burns etc

Question 43

How does fever affect energy requirements?

Answer 43

Increases

Question 44

How does early feeding affect animals with tumours?

Answer 44

Doesn't increase survival time, but does improve QOL as faster recovery and increased immunocompetence

Question 45

What are two indications for a restricted protein food?

Answer 45

Hepatic encephalopathy or severe uraemia

Question 46

Why should food fed by tube be iso-osmolar?

Answer 46

To prevent diarrhoea

Question 47

What are the problems with feeding cold food?

Answer 47

Cold food can induce vomiting, give rapid gastric emptying giving diarrhoea, and patient has to spend energy warming it

Question 48

What are three fatal complications of TPN?

Answer 48

Sepsis, thrombosis, intestinal atrophy

Question 49

What happens to enterocytes in TPN?

Answer 49

Hypofunctional, hypoplastic, altered myoelectrical activity, increased upper GI bleeding

Question 50

When is the only time you should use TPN?

Answer 50

Only if can't absorb enteral nutrition for over a week

Question 51

What is the appetite stimulant of choice?

Answer 51

Mirtazipine

Question 52

When is the only time vitamin B works to stimulate appetite?

Answer 52

If depleted

Question 53

For how lon can you use an oesophagostomy tube?

Answer 53

Several weeks

Question 54

Why is a polyurethane tube better than PVC?

Answer 54

PVC is cheaper but hardens in stomach acid and kinks so hard to remove

Question 55

For how long can you use an NG tube?

Answer 55

Less than 1 week

Question 56

Can you send home with an oesophagostomy tube?

Answer 56

No

Question 57

For how long must a gastrotomy tube be in place before the adhesions form between the stomach and body wall?

Answer 57

At least 5-7 days - contraindicated below this

Question 58

How do you know when to remove a feeding tube?

Answer 58

Until eating 85% of requirements voluntarily