Nutritional history, examination and assessment

Question 1

How much of the UK pop is affected by malnutrition?

Answer 1

5%- all ages - under or overweight
30% acute hospital admissions
35% of care home admission
10% presenting to GP

Question 2

Why do people become malnourished?

Answer 2

Difficulty eating and swallowing
Depression
Hospital environment 
medication 
increased nutritional requirements 
nausea and vomiting
anxiety
pain
malabsorption

Question 3

What are the effects of malnutrition?

Answer 3

impaired survival
poor wound healing
anastomotic leaks 
bed sores 
increased sepsis 
poor motivation 
delayed rehabilitation

Question 4

What is the NICE guidance on malnutrition upon patient admission to hospital?

Answer 4

pt should be screened for malnutrition within 24 hours of admission and weekly

Question 5

When is BMI not applicable?

Answer 5

for children

and pregnant women

Question 6

What are the levels of BMI?

Answer 6

Underweight <18.5
Normal 18.5-25
Overweight 25-30
Obese >30

Question 7

What is the recommended tool by NICE to assess malnutrition?

Answer 7

MUST

• M = malnutrition
• U = universal
• S = Screening
• T = tool

= BMI, unintentional weight loss and acute illness score

Question 8

What are the limitations of BMI/MUST?

Answer 8

Fluid increases
Lean body mass (muscle) wastage
Weight and BMI likely to remain the same or increase
Poor intake from chronic illness

Question 9

Is obesity classified as malnutrition and if so why?

Answer 9

yes, calorific excess can hide micronutrient and vitamin deficiencies
loss of weight in obese people may be obscure
obese pts very rarely appear classically malnourished

Question 10

What are the problems with anthropometrics?

Answer 10

Like weight, a change is better than a one off measurement
Inter-observer variation
Intra-observer variation - some people will measure it differently each time
Time consuming

Question 11

What is a much better test than anthropometrics?

Answer 11

hand grip test

• use non-dominant hand
• functional measure of nutritional status
• correlates well with nutritional depletion and repletion
• less intra and inter observer variation
• and very quick and easy

Question 12

What are some key questions to ask to determine whether a pts weight has changed?

Answer 12

change in clothes/dress size
belt notch
denture fit - if someone loses weight dentures may not fit properly 
temporalis wasting 
skin lesions

Question 13

Why shouldn’t you rely on serum markers when assessing malnutrition?

Answer 13

albumin and other serum protein markers = have marked limitations
all are affected by active inflammation
albumin also affect by IV fluid and liver dysfunction
many pt with severe malnutrition and BMI <14 will have normal albumin levels

trace elements are also affected by acute inflammation
- iron bound into cells so serum levels fall
copper levels rise as toxic to bacteria

Question 14

What are the limitations of scanning?

Answer 14

E.g dexa and ct scans

- both limited by use of ionising radiation, time consuming and expensive

Question 15

What does a dexa scan do?

Answer 15

differentiates fat mass from lean mass and bone mass

- increase in extracellular fluid = appears as lean mass

Question 16

What does bioelectrical impedance analysis do?

Answer 16

determine fat free mass, total body water, intra-cellular and extracellular water in an individual with no disturbance in water and electrolytes
uses multiple frequencies of current and noting the impedence
relies on using appropraite population, age and pathology specific equations

Question 17

What are the pros and cons of bioelectrical impedence analysis ?

Answer 17

portable, cheap and acceptable to pt

clinical use at extremes of BMI (<16 and >34) or abnormal hydration it cannot be recommended

useful clinical research technique but not for routine clinical use

Question 18

How can you help to assess a pts portion size?

Answer 18

use:

• pictures of food
• models of food
• weighed record most accurate but quite impractical
• food bought record (supermarket)

Question 19

What do the red trays/jugs/beakers mean in hospital?

Answer 19

more attention needs to be paid to these pts, what’s being eaten and what’s being left

Question 20

What is refeeding syndrome and what are the characteristic features of it?

Answer 20

sudden change from a catabolic to an anabolic state
With glucose as the main energy source there is a sudden shift of electrolytes and minerals
change in fluid dynamics
vitamin deficiencies cause abnormal biochemical pathways

Question 21

What are the characteristic features of starvation state?

Answer 21

Glycogen stores depleted
Intra and extra-cellular ions are depleted overall but serum conc may well be normal due to body water losses at the expense of intracellular stores
fat metabolism is the prime source of energy

Question 22

What can hypophosphataemia cause?

Answer 22

weakness, myalgia, rhabdomyolysis, dyspnoea, ataxia, delirium, convulsions and coma

Question 23

What can hypomagnesaemia cause?

Answer 23

implicated in hypokalaemia and hypocalcaemia
it is required for ADP/ATP production
lack of it can cause carpal spasms - can’t unscrew their hands

Question 24

What can hypocalcaemia and hypomagnesaemia lead to ?

Answer 24

tetany and together with hypokalaemia they can cause cardiac arrhythmias

Question 25

What can happen if during starvation your biochemistry adapts to lipid metabolism?

Answer 25

it can lead to hyperglycaemia which can lead to hyperosmosis which leads to poor neutrophil function, cerebral oedema, convulsions and coma

Question 26

Why is thiamine important and what does a deficiency in it cause?

Answer 26

essential for glucose metabolism to produce energy 
therefore lack of it can lead to:
- wernicke's encephalopathy 
- chronically = korsakoff's syndrome 
- dry beri-beri

Question 27

What effect does the increased Na excretion during starvation have?

Answer 27

leads to a negative balance
upon feeding sodium urinary losses stop and therefore there is reduced urine output
sodium and water retention together with hyperglycaemia may lead to cerebral oedema

Question 28

What is the NICE guidance with regards to starting re-feeding?

Answer 28

starting nutrition support at a max of 10kcal/kg/day and increasing levels slowly to meet or exceed full needs by 4-7 days
- use only 5kcal/kg/day in extreme cases

It is vital to monitor cardiac rhythm and restore circulatory volume and monitor fluid balance and overall clinical status closely

Question 29

What are the recommendations for Na and water ?

Answer 29

keep fluid input low, enough to maintain renal function

• about 20-30ml/kg/day
• restrict sodium to <1mmol/kg/day

this can cause challenges when trying to replace electrolytes

Question 30

What type of feeding is more likely to cause refeeding hypophosphataemia?

Answer 30

enteral tube feeding instead of paraenteral feeding