Introduction to Nutritional Assessment Flashcards
What is effection fo Malnutrition and their complications?
- Impaired immune response: Infection
- Impaired wound healing: Prolonged recovery
- Muscle wasting: Inactivity, Falls
- Decreased respiratory and cardiac muscle contraction: Pneumonia, Heart failure
- Inactivity: Thromboembolism, Pressure sores
- Impaired thermoregulation: Hypothermia
What is the Nutritional status?
‘Condition of body resulting from intake, absorption and utilisation of food, taking into account factors of pathological significance’
What does a nutriotional assement involve?
Involves
- Screening Tools
- Dietary Assessment
- Clinical Assessment
- Biochemical Assessment
- Calorimetry,
Wh does we perform a nutrtional assessment?
- Determine whether nutritional needs being met
- Identify patients at higher risk of morbidity/mortality without nutrition support
- Chart patients progress with time
What are some screening Tools?
Subjective Global Assessment (SGA)
- Symptoms
- History
- Examination findings
Likelihood of Malnutrition Index (LMI)
- Biochemistry
- Haematology
- Examination findings
Malnutrition Universal Screening Tool (MUST)
What is a dietary assement used for?
Identify:
- Loss of appetite
- Difficulty buying / preparing food
- Difficulty eating food
What are the methods for a dietary assessment?
- Quantitative food diary
- Food frequency questionnaires
- Photographs
How is a clinical assessment of nutrition undertaken?
Clinical History
- Increased nutritional requirements
- Increased nutrient losses
- Decreased nutrient absorption
Clinical Examination
- Generalised signs of malnutrition
- Signs / Symptoms of specific nutritional disorders Waist circumference
Anthropometric Measurements
- Height / Weight / BMI
- BMI = Weight (Kg) / Height2 (m
- Skinfold thickness
- Mid-arm circumference
How is nutrition biochemically assessed?
Measure
- Albumin
- Pre-albumin
- IGF-1
- Transferrin
- Retinol binding protein
- Fibronectin
What can Biochemcial Assessment of Nutrition be affected by?
- Acute phase response
- Concurrent liver and renal disease
- Hydration status
How can Calorimetry be conducted?
- Can be directly calculated by measuring the heat expended by an individual exercising in an enclosed chamber
- Can be indirectly calculating by measuring the oxygen consumed and the amount of carbon dioxide expended
How can X-Ray be used for assessment of nutrition?
Can be used through X-ray and DEXA scan to look at the body composition
What are sources of Energy in the UK Adult diet?
- Carbohydrates = 45.7%
- Protein = 15.6%
- Fat = 33.3%
- Alcohol = 5.2%
What are the energy requirements within the body?
Basal metabolism:
- Biosynthesis of tissues during continuous turnover = 40%
- Maintenance of ionic gradients across membranes, especially electrical activity of nerve cells = 40%
- Involuntary muscle contraction of breathing, peristalsis, heart = 20%
Additional needs:
- Biosynthesis of new tissue during energy storage, growth, replacement of any losses
- Voluntary muscle contraction
- Thermoregulation
- Thermogenesis
How is the Total Energy Expenditure calculated?
- Alteration in BMR due to disease process +
- Physical Activity +
- Metabolic response to food (dietary induced thermogenesis; DIT)
How is the an individuals enery requirements estimated in clinical practice?
- Estimating the BMR
- Adding appropriate stress factor (disease process)
- Adding a combined factor for activity and DIT
How is the BMR estimated?
BMR = ‘the energy expenditure (eg. kcal/day) of the body at rest, at thermoneutrality, and in the postabsorptive state’. BMR is 45-70% of TEE
BMR is principally determined by body mass and therefore, varies with:
- Body weight
- Body composition
- Age
- Gender
How is BMR estimated?
Schofield Equation
What affects the BMR estimate calculation?
- Nutritional status
- Hormonal effects
- Pharmacological
- Pregnancy and lactation
- Disease
- Trauma
- Ambient temp etc
What are the stress factors in Clinical estimate of TEE?
- Severe sepsis = 10-30%
- Extensive surgery = 10-30%
- Fractures/trauma = 10-30%
- Burns/wounds = 50-150%
- RDS = 20%
What examples of Physical Activity and DIT?
1. Activity = energy expended during active movement of skeletal muscle
Hospital:
- Bedbound immobile = +20%
- Bedbound mobile/ sitting = +30%
- Mobile on ward = +40%
Community – multiply the BMR by Physical Actively Level (PAL):
- Sedentary or Light = 1.40 – 1.89
- Moderately Active = 1.70 – 1.69
- Vigorous = 2.00 – 2.40
2. Add 10% for specific dynamic action of food
What are the sources of Proteins?
- Grains
- Cereals
- Fish
- Meat
- Nuts
- Dairy
What are requirements for Protein?
- Adults 1.0 g/Kg/day (0.16 g Nitrogen/Kg/day)
- Children 1.5 g/Kg/day (0.24 g Nitrogen/Kg/day)
- Neonates 2.5 g/Kg/day (0.4 g Nitrogen/Kg/day)
What are the constant obligatory lossess of Proteins?
- Urine - urea (also ammonia, urate, creatinine and some free amino acids)
- Faeces
- Desquamated skin
What are the states of Proteins?
Anabolic state
- Intake/Synthesis of protein/amino acid sources greater than rate of utilisation and/or excretion
Catabolic state
- Utilisation and/or excretion of protein/amino stores greater than intake/synthesis
How do we calculate Protein Loss?
Nitrogen excretion (g/24hr) = (Urine urea (mmol/24hr) x 28)/1000
+20% to account for non-urea urinary nitrogen losses
+2 g to account for non-urinary nitrogen losses
- Nitrogen excretion < Nitrogen intake = Anabolic
- Nitrogen excretion > Nitrogen intake = Catabolic
How can Protein Depletion occur?
- Failure to meet energy requirements, resulting in use of tissue protein as an energy source
- Failure to absorb or utilise dietary protein as a result of GI disorders or liver disease
- Catabolic response to trauma, sepsis, surgery, with net negative nitrogen balance
- Excessive protein loss from body due to eg burns, nephrotic syndrome, exudative losses
What doe Long term depletion of protein result in?
- Stunted growth
- Poor wound healing
- Increased susceptibility to infection
- Anaemia
What are sources of Carbohydrate Metabolism?
- Grains
- Pulses
- Fruit
- Rice
- Maize
- Refined sugars
Typically, 4-5 g/Kg/day
How are Carbohydrates stored in the body?
- Liver and muscle major store of body CHO in form of glycogen
- Hepatic glycogen depleted within 24 hrs if no CHO ingestion, after this blood glucose concentrations maintained by gluconeogenesis from amino acids, lactate and glycerol
- No specific syndromes associated with Carbohydrate deficiency alone
What are sources of Fat?
- Meat
- Dairy
- Nuts/Seeds/Fish/Olives/Avocado etc
What are fat requirements from the body?
- Fat intake no more than 35% total energy requirements
- No more than 1/3 of this supplied as saturated fat
- Adults ~1-1.5 g/Kg/day
What are the sign/sumtptoms associated with Fat deficiency?
- Dermatitis
- Night blindness
- Rickets / Osteomalacia
- Fragile red blood cells
- Poor clotting function
- Neuropathy
