1. Nutritional Assessment Workshop
Nicola Riley
Concord Repatriation General Hospital
Emma McNamara

2. What is Nutritional Assessment?
“the evaluation of nutrition needs of individuals based upon appropriate biochemical, anthropometric, physical, and dietary data to determine nutrient needs and recommended appropriate nutrition intake including enteral and parenteral nutrition”
- American Dietetic Association

3. Nutritional Assessment & Clinical Application - Overall View
Nutrition Management:
Assessment
Intervention
Follow-up / Review
Evaluation
Consider:
Health care setting
Disease / condition
Lifecycle / physiological state

4. Nutritional Status
“Nutritional Status expresses the degree to which physiologic needs for nutrients are met”
Optimal NS = Balance between intake and requirement
Malnutrition
state caused by nutritional deficiency
Reversible by providing appropriate nutrition support
Deficiency vs Overload
(can be combination of both)
“whole person” focus, not just disease or condition focus.

5. Nutritional Risk
Critically unwell patients may be well nourished but high nutritional risk
Illness, injury, infection
Metabolic derangements
May have significant affect on nutritional status
May lead to malnutrition
Cannot be corrected by nutrition support alone
Patients at high nutritional risk will require early nutritional intervention and close monitoring

6. Why do we need to identify malnutrition?
Malnutrition is associated with:
 length of stay in hospital
 complications
 hospital costs
 mortality rates

7. Screening vs Assessment

8. Nutrition Screening Tools
Requirements
quick and simple to administer
sensitive enough to identify individuals at risk
appropriate for client group being screened
capable of being used by non-dietitians
reproducible when used by different observers
able to guide non dietetic staff into taking appropriate action for findings recorded

9. Malnutrition Screening Tool (MST)
Have you lost weight recently without trying?
If NO
If unsure
If YES, how much weight have you lost?
1 – 5 kg (2 – 11 lb)
6 – 10 kg (1 – 1½ st)
11 – 15 kg (1¾ - 2⅓ st)
> 15 kg (> 2⅓ st)
Unsure 2 1 3 4
Have you been eating poorly because of a decreased appetite?
If YES
Total
If the score is 2 or more please refer to the dietitian.
(Ref: Ferguson M et al, Nutrition 15: , 1999)

10. The Short Nutritional Assessment Questionnaire (SNAQ)
Score
Did you lose weight unintentionally?
>6kg in the past 6 month 3
>3kg in the past month 2
Did you experience a decreased appetite over the past month? 1
Did you use supplemental drinks or tube feeding over the past month?

12. Nutritional Assessment Tools
No single / standard way of assessing nutritional status
Various validated assessment tools developed
some disease specific
some age specific
2 examples
Mini Nutritional Assessment (MNA)
Subjective Global Assessment (SGA)

13. Mini Nutritional Assessment (MNA)
Screening and Assessment tool for the identification of malnutrition in the elderly
Considers:
Dietary Intake – foods, patterns
Weight change, BMI, Muscle circumferences
Functional impairment, Independence, Living arrangements
Psychological issues, Self assessment

14. Subjective Global Assessment
Valid assessment tool
Strong correlation with other subjective and objective measures of nutrition
Highly predictive of nutritional status in a number of different patient groups
Quick, simple and reliable

15. Subjective Global Assessment…features
Medical History
Weight change
Dietary intake
GI symptoms
Functional impairment
Physical Examination
Loss of subcutaneous fat
Muscle wasting
Oedema and ascites

16. Subjective Global Assessment …Classifications
A Well nourished
B Moderately malnourished or suspected of malnutrition
C Severely malnourished

17. Full Nutrition Assessment Step 1…Data collection
Systematic Approach
Assessment based on clinical/psychosocial/physical information
Dietary
Anthropometric
Biochemical
Physical
Including
Subjective (eg. signs/symptoms of nutritional problem, appetite)
Objective (eg. Lab results)

18. Data Collection… An Example… A B C D E
A Anthropometry
B Biochemical Data
C Clinical signs and symptoms, medical condition
D Dietary Intake
E Exercise (Energy balance – expenditure)
Consider current level, history and changes

19. Anthropometry Height Weight Weight history / pattern (% weight change)
Weight for Height
BMI
Growth Pattern, head circumference (paediatrics)
MAMC
TSF
Waist circumference
Hip circumference
WHR
Be aware of fluid status, presence of oedema.

20. Anthropometry – Body Composition Muscle, Fat, Bone, Water
Body Mass:
LBM – Body mass that contains small % (~3%) essential fat
[Essential fat + Muscle + Water + Bone]
Fat Free Mass (FFM)
Fat Store:
Essential Fat for physiological function, eg. fat stored in muscle, liver, heart
Storage fat in adipose tissue – visceral fat and subcutaneous fat

21. Body Compostion cont’d.
Practical Methods in Clinical Setting:
Weight, height & weight Hx
Skinfolds, circumferences
TSF, MAMC,WHR
More precise, occasional use:
Bioelectrical Impedance Analysis (BIA)
FFM, % body fat
Dynamometry (grip strength)
Precise, Expensive, Research purposes:
CT, MRI, Dexascan, TBK,TBN

22. Biochemistry & other Blood Tests (See also disease/condition specific lectures)
Objective measures
No single test is diagnostic
Consider “normal / recommended range” for various and combination of conditions, eg. age, gender, physiological state, disease type and stage
Consider clinical significance of test result
Test result may reflect immediate intake (eg glucose) or long term status (HbA1c)

23. Other factors to Consider…
Other factors can mask/influence test results eg.
Acute phase response due to stress / injury ( reduced albumin)
GI bleed (higher urea)
blood transfusion (higher serum K and Hb)
Surgery (lower Hb and albumin)

24. Acute Phase Response Inflammatory processes (shock, trauma, sepsis)
liver protein synthesis shifts from visceral proteins, e.g. albumin and prealbumin to acute phase proteins
Visceral proteins may reflect ‘nutritional risk’ not nutritional status

25. Nutritional Indicators
Ideal indicator or marker is sensitive and specific to nutritional intake
Commonly Used “Nutritional Indicators”
Albumin
Pre-albumin
Transferrin
Retinol-binding protein

26. Albumin Synthesised in the liver
May be useful indicator of nutritional status in “healthy” person.
Not a good indicator of protein status during critical illness (due to acute phase response)
Long half life (14-20 days) and large body pool  slow to respond to improvements in clinical status

27. Factors Affecting Serum Albumin Levels
Increased in:
Dehydration, blood transfusions, exogenous albumin
Decreased in:
Overhydration, hepatic failure, inflammation, infection, metabolic stress, post-op, bed rest, pregnancy, nephrotic syndrome.

28. Pre-albumin Also known as Transthyretin, thyroxine binding protein.
Synthesised in the liver
Relatively short half life (2 days)
Negative acute phase reactant -  with inflammatory response
May be useful in healthy population

29. Transferrin and RBP Transferrin Retinol Binding Protein (RBP)
Half life 8-10 days
Poor correlation with nutrition status
Involved with iron transport, influenced by iron status
Retinol Binding Protein (RBP)
Half life 12 hours
Affected by renal function, Vitamin A and Zn status
Unreliable measure of nutritional status

30. Biochemistry & other Blood Tests, cont’d (See also disease/condition specific lectures)
Interference – drugs, sampling
Nutrient-nutrient interactions, drug-nutrient interactions
Be aware of hydration status
Must interpret lab results with other nutritional parameters

31. Clinical issues to consider:
Medical history, treatment and medications
Significant factors affecting nutritional intake
Fluid balance – input and output, Bowel habits
Physical assessment of nutritional status
Clinical signs and symptoms

32. Clinical Signs and Symptoms
Subjective, impression
Descriptive, observation
Appearance
Visual examination
Needs clinical judgement
Eg muscle wasting, malnutrition
Symptoms
Recall, report by subjects
Descriptive
Eg nausea, itchiness, diarrhoea, anorexia

33. Dietary Intake Is intake meeting requirement?
(See relevant lectures in dietary intake, RDIs, etc)
Is intake meeting requirement?
Basic nutrition adequacy
Special requirement / disease / conditions
Consider factors affecting intake
Consider clinical, nutritional and psycho-social issues
Methods of collecting information/data
?Relevant and practical

34. Exercise – Energy Balance
Nutrition and exercise closely linked – metabolic and physical fitness
Functional capacity and Nutritional status
Correlation between muscle mass and physical strength, nutritional status and physical function
Energy Balance to attain optimal weight and body composition
Bed Rest / Inactivity
Negative effects on muscles, bone and CV system, eg. 8 g protein loss / day of bed rest
Exercise – affects on appetite, bowel function

35. Estimating Nutritional requirements
Consider
Energy
Protein
Fluid
RDIs for micronutrients

36. Estimating Energy Requirements
Indirect Calorimetry
preferred method
use of a metabolic monitor/cart
measures respiratory gas exchanges
Differences in oxygen and carbon dioxide content between air going in and air coming out  respiratory exchange  energy expenditure
(Ref: Mann & Truswell(ed) Essentials of Human Nutrition, Chap. 5)

37. Harris Benedict Equation
Devised in 1919
Multiple regression analysis of the gender, age, height and weight of 239 healthy volunteers
Recent review of data and methodology - still valid (Frankenfield et al, 1998, JADA)
Basal energy expenditure (BEE)
= energy expended by a fasting subject at rest in a ‘thermoneutral’ environment

38. Harris Benedict Equation
Males (kJ/24hr)
BEE = (57.5 x W) + (20.9 x H) - (28.3 x A)
Females (kJ/24hr)
BEE = (40.0 x W) + (7.7 x H) - (19.6 x A)
W = actual weight in kg, H = height in cm,
A = age in years.

39. Schofield Equation
Original equation (Schofield, 1985) derived from a study group of 5000 healthy adults
Modified by COMA Panel on Dietary Reference Values (UK Dept of Health, 1991)
excluded some data from developing nations
additional equations for people over age of 75 yrs, based on Italian data
Limitations - ?validity with obese clients, some ethnic groups, ?applicable to Australian population.

40. Original Schofield Equations (1985)
Males
Age (yrs) kJ /24hr W W W W
Females
Age (yrs) kJ / 24hr W W W W

41. Modified Schofield Equations (1991)
Males
Age (yrs) kJ /24hr W W W W W
Females
Age (yrs) kJ / 24hr W W W W W

42. Estimating Energy requirements
Estimate BMR/BEE for healthy adult using predictive equation
Adjust for stress using injury factor
Adjust for activity using activity
Energy requirement = BEE x Injury/Stress factor x Activity factor

43. Activity Factors Resting sedated +/- ventilated 1.0
Resting conscious
Bedrest (moving self around bed) 1.2
Light (mobilizing around ward) 1.3
Moderate (regular, intense physio) 1.4

44. Injury Factors Medical (IBD, liver/pancreatic d) 1.1-1.2
Surgical (transpl, fistula)
Cancer (tumour/leukaemia)
Trauma (or minor burns)
Sepsis (or other major infection)
Major burns
* Refer also to nutrition support and specific clinical lectures

45. Estimating Protein / Nitrogen Requirements
From measuring Nitrogen losses from the body (urine, faeces, fistulae/drain losses, burn exudates)
Urinary nitrogen excretion can be estimated by measuring urinary urea nitrogen(UUN) excretion from a 24hr urine sample.
Urea production influenced by liver failure, sepsis, stress
 insensitive and unreliable in clinically unstable patients

46. Estimating Protein / Nitrogen Requirements
Using RDA’s
Healthy adult g/kg BW
Increased metabolic needs during periods of stress
Mild/intermediate stress state
eg surgery, fractures g/kg BW
Cancer g/kg BW
Multiple trauma, /kg BW
extensive burns(>30%)

47. Fluid Requirements Different methods used: 35 – 45 mL/kg body weight
30mL for older adults
40 – 45 mL for active young adult
0.24mL/kJ energy given
1500mL + add 20mL per additional kg over 20kg