The basics of nutrition and the diagnosis of malnutrition

Question 1

Nutrition definition

Answer 1

“The branch of science that studies the process by which living organisms take in and use food for the maintenance of life, growth, reproduction, the functioning of organs and tissues, and the production of energy.”

Question 2

Macronutrients

Answer 2

protein, fats, carbohydrates. Required in gram amounts and are major sources of energy and amino acids.

Question 3

Micronutrients

Answer 3

– vitamins, minerals, trace elements. Minerals required in gram or milligram amounts, trace elements required in microgram amounts

Question 4

Assessment of nutritional status

Answer 4

NICE CG32 states that:

• All hospital inpatients and all outpatients at their first clinic appointment should be screened. This should be repeated weekly for inpatients and when there is clinical concern for outpatients
• Groups of patients considered to be low risk may be opted out. There must be an explicit process for opt-out decisions within a clinical governance structure
• People in care homes to be screened on admission and where there is clinical concern
• Screening upon registration at GP surgeries and when there is clinical concern
• Screening should also be considered at other opportunities (e.g. health checks, flu injections)
• Screening should assess:
• BMI
• % unintentional weight loss
• Suggested tool is (MUST) as developed by BAPEN

Question 5

What is ‘MUST’ tool

Answer 5

• ‘MUST’ is a five-step screening tool to identify adults, who are malnourished, at risk of malnutrition (undernutrition), or obese. It also includes management guidelines which can be used to develop a care plan.
• It is for use in hospitals, community and other care settings and can be used by all care workers

Question 6

Nutrition support should be considered in people who are malnourished, as defined by any of the following

Answer 6

a BMI of less than 18.5 kg/m2

unintentional weight loss greater than 10% within the last 3–6 months

a BMI of less than 20 kg/m2 and unintentional weight loss greater than 5% within the last 3–6 months.

Question 7

For people who are not severely ill or injured, nor at risk of refeeding syndrome, the suggested nutritional prescription for total intake[7] should provide all of the following:

Answer 7

25–35 kcal/kg/day total energy (including that derived from protein)

0.8–1.5 g protein (0.13–0.24 g nitrogen)/kg/day

30–35 ml fluid/kg (with allowance for extra losses from drains and fistulae, for example, and extra input from other sources – for example, intravenous drugs)

adequate electrolytes, minerals, micronutrients (allowing for any pre-existing deficits, excessive losses or increased demands) and fibre if appropriate.

Question 8

Criteria for determining people at high risk of developing refeeding problem

Answer 8

Patient has one or more of the following:

• BMI less than 16 kg/m2
• unintentional weight loss greater than 15% within the last 3–6 months
• little or no nutritional intake for more than 10 days
• low levels of potassium, phosphate or magnesium prior to feeding.

Or patient has two or more of the following:

• BMI less than 18.5 kg/m2
• unintentional weight loss greater than 10% within the last 3–6 months
• little or no nutritional intake for more than 5 days
• a history of alcohol abuse or drugs including insulin, chemotherapy, antacids or diuretics.

Question 9

The prescription for people at high risk of developing refeeding problems should consider:

Answer 9

starting nutrition support at a maximum of 10 kcal/kg/day, increasing levels slowly to meet or exceed full needs by 4–7 days

using only 5 kcal/kg/day in extreme cases (for example, BMI less than 14 kg/m2 or negligible intake for more than 15 days) and monitoring cardiac rhythm continually in these people and any others who already have or develop any cardiac arrythmias

restoring circulatory volume and monitoring fluid balance and overall clinical status closely

providing immediately before and during the first 10 days of feeding: oral thiamin 200–300 mg daily, vitamin B co strong 1 or 2 tablets, three times a day (or full dose daily intravenous vitamin B preparation, if necessary) and a balanced multivitamin/trace element supplement once daily

providing oral, enteral or intravenous supplements of potassium (likely requirement 2–4 mmol/kg/day), phosphate (likely requirement 0.3–0.6 mmol/kg/day) and magnesium (likely requirement 0.2 mmol/kg/day intravenous, 0.4 mmol/kg/day oral) unless pre-feeding plasma levels are high. Pre-feeding correction of low plasma levels is unnecessary.

Question 10

Obvious indicators of dysphagia

Answer 10

Difficult, painful chewing or swallowing

Regurgitation of undigested food

Difficulty controlling food or liquid in the mouth

Drooling

Hoarse voice

Coughing or choking before, during or after swallowing

Globus sensation

Nasal regurgitation

Feeling of obstruction

Unintentional weight loss – for example, in people with dementia

Question 11

Less obvious indicators of dysphagia

Answer 11

Change in respiration pattern

Unexplained temperature spikes

Wet voice quality

Tongue fasciculation (may be indicative of motor neurone disease)

Xerostomia

Heartburn

Change in eating habits – for example, eating slowly or avoiding social occasions

Frequent throat clearing

Recurrent chest infections

Atypical chest pain

Question 12

Vitamin D is converted to

Answer 12

25hydroxyVitaminD in the
liver and then on to 1,25-dihydroxyVitaminD in the kidney. It is this
which has potent metabolic effects

Question 13

There are two types of Vitamin D:

Answer 13

• Ergocalciferol (Vitamin D2) a plant product and
  -Colecalciferol (Vitamin
  D3) which is a fish or mammal
  product.

Question 14

what should not

be used for the treatment of simple Vitamin D deficiency.

Answer 14

‘Activated Vitamin D’ preparations such as Calcitriol or Alfacalcidol.

They are ineffective in treating simple Vitamin D deficiency and can cause severe adverse effects, particularly hypercalcaemia.

Question 15

Vit D ‘insufficiency’

Answer 15

between 25 and 50 nmol/L

Question 16

at risk of Vitamin D deficiency

Answer 16

1. increased need:
•	 pregnant and breastfeeding women
•	 infants
•	 twin and multiple pregnancies
•	 adolescents
•	 obesity

2. Reduced sun exposure:
   • northern latitude, especially above 50 degrees latitude (eg UK)
   • season – in winter and spring
   • Asian and African people – dark skin needs more sunshine to
   make Vitamin D
   • wearing concealing clothing
   • immobility, eg inpatients or those with conditions like cerebral
   palsy
   • excessive use of sun block – most block UVB more than UVA
3. Limited diet (but remember sunshine is most important source
   of Vitamin D):
   • vegetarians and vegans
   • prolonged breastfeeding – even if mother has sufficient Vitamin D
   • exclusion diets – eg milk allergy
   • malabsorption
   • liver disease
   • renal disease
   • some drugs – eg Anticonvulsants, Anti-TB drugs

Question 17

The Department of Health and the Chief Medical Officers recommend a

Answer 17

dose of 7-8.5 micrograms (approx 300 units) for ALL children from six
months to five years of age

Question 18

high level of PTH is usually due to

Answer 18

Vitamin D deficiency or a lack of Calcium in the diet. Other causes (eg parathyroid tumours or renal failure) are rare

Question 19

COMA used four types of Dietary Reference Values:

Answer 19

Estimated Average Requirements (EARs)
The EAR is an estimate of the average requirement of energy or a nutrient needed
by a group of people (i.e. approximately 50% of people will require less, and 50% will
require more).

Reference Nutrient Intakes (RNIs)
The RNI is the amount of a nutrient that is enough to ensure that the needs of
nearly all a group (97.5%) are being met.

Lower Reference Nutrient Intakes (LRNIs)
The LRNI is the amount of a nutrient that is enough for only a small number of
people in a group who have low requirements (2.5%) i.e. the majority need more.

Safe Intake
The Safe intake is used where there is insufficient evidence to set an EAR, RNI or
LRNI. The safe intake is the amount judged to be enough for almost everyone, but
below a level that could have undesirable effects.

Question 20

Step 1 of MUST tool

Answer 20

Step 1: Measure height and weight to get a BMI score using chart provided. If unable to obtain height and weight, use the alternative procedures shown in this guide. BMI kg/m2

BMI >20(>30 Obese) = Score 0
BMI 18.5 -20 = Score 1
BMI <18.5 = Score 2

Question 21

Step 2 of MUST tool

Answer 21

Step 2: Note percentage unplanned weight loss and score using tables provided.

% Score
<5 = 0
5-10 = 1
>10 = 2

Question 22

Step 3 of MUST tool

Answer 22

Step 3: Establish acute disease effect and score.

• If patient is acutely ill and there has been or is likely to be no nutritional intake for >5 days give Score of 2

Question 23

Step 4 of MUST tool

Answer 23

Step 4: Add scores from steps 1, 2 and 3 together to obtain overall risk of malnutrition.

Score 0 Low Risk:
Repeat screening: Hospital – weekly, Care Homes – monthly, Community – annually for special groups e.g. those >75 yrs

Score 1 Medium Risk:
Document dietary intake for 3 days if subject in hospital or care home. If improved or adequate intake – little clinical concern; if no improvement – clinical concern - follow local policy
Repeat screening: Hospital – weekly, Care Home – at least monthly, Community – at least every 2-3 months

Score 2 or more High Risk:
Refer to dietitian, Nutritional Support Team or implement
local policy.
Improve and increase overall nutritional intake
Monitor and review care plan: Hospital – weekly, Care Home – monthly, Community – monthly

Question 24

Step 5 of MUST tool

Answer 24

Step 5: Use management guidelines and/or local policy to develop care plan.