Nutritional Assessment Workshop

1. Nutritional Assessment Workshop Nicola Riley Concord Repatriation General Hospital nicola.riley@sswahs.nsw.gov.au Emma McNamara Concord Repatriation General Hospital emma.mcnamara@sswahs.nsw.gov.au

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) If the score is 2 or more please refer to the dietitian. (Ref: Ferguson M et al, Nutrition 15: 458-464, 1999)

10. The Short Nutritional Assessment Questionnaire (SNAQ)

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 AssessmentStep 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. 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. Anthropometry

20. 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 Anthropometry – Body CompositionMuscle, Fat, Bone, Water

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 • 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. Signs 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 Clinical Signs and Symptoms

33. Dietary Intake (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 = 278 + (57.5 x W) + (20.9 x H) - (28.3 x A) Females (kJ/24hr) BEE = 2741 + (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. Males Age (yrs) kJ /24hr 15-18 74W + 2754 18-30 63W + 2896 30-60 48W + 3653 60+ 49W + 2459 Females Age (yrs) kJ / 24hr 15 - 18 56W + 2898 18-30 62W + 2036 30-60 34W + 3538 60+ 38W + 2755 Original Schofield Equations (1985)

41. Males Age (yrs) kJ /24hr 10-17 74W + 2754 18-29 63W + 2896 30-59 48W + 3653 60-74 50W + 2930 75+ 35W + 3434 Females Age (yrs) kJ / 24hr 10-17 56W + 2898 18-29 62W + 2036 30-59 34W + 3538 60-74 39W + 2875 75+ 41W + 2610 Modified Schofield Equations (1991)

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 1.1 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) 1.2-1.4 Cancer (tumour/leukaemia) 1.2-1.4 Trauma (or minor burns) 1.2-1.4 Sepsis (or other major infection) 1.3-1.4 Major burns 1.5-1.6 * 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 0.75g/kg BW Increased metabolic needs during periods of stress • Mild/intermediate stress state eg surgery, fractures 1-1.5g/kg BW • Cancer 1.2-1.5g/kg BW • Multiple trauma, 1.5+/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