Nutrition Flashcards
Malnutrition
State where deficiency, excess or imbalance of nutrients causes measurable adverse effects on:
- Tissue or body form (shape, size and composition).
- Function and clinical outcome.
Symptoms of malnutrition
- Weight loss/loss of appetite
- Tiredness, lack of energy, lethargy
- Depression
- Poor concentration
- Poor growth in children
Cost of malnutrition: primary care
- GP visits
- Rx costs
- Hospital referrals
- Care packages
Cost of malnutrition: secondary care
- Medical and surgical complications
- Length of hospital stay
- Readmissions
- Death
Causes of malnutrition
- Altered nutrient processing
- Excess losses
- Impaired intake
- Impaired digestion and absorption
Altered nutrient processing
- Increased metabolic demand
- Liver dysfunction
Impaired intake
- Dysphagia
- Depression/psychological stress
- Mucositis
- Poor diet
- Poor appetite
- Pain/nausea with food
- Unconsciousness
Impaired digestion and absorption
- Problems with the stomach, small intestine, pancreas and liver.
Excess losses
- Diarrhoea/vomiting
- Fistulae
- NG tube drainage
- Surgical drains
- Stoma
Consequences of malnutrition
- Decreased immunity
- Decreased CO
- Decreased renal function (loss of ability to excrete sodium and water)
- Decrease liver function
- Hypothermia
- Loss of strength
- Depression
- Secondary anorexia
- Impaired gut integrity and immunity
- Impaired wound healing
- Loss of muscle and hypoxic responses (ventilation)
Malnutrition Universal Screening Tool (MUST)
- Calculate BMI using height and weight
- Score % unplanned weight loss
- Score acute disease effect
- Add scores from steps 1-3 for complete score
- Refer to local management guidelines/policies to create an action plan.
- Score >2 is high risk (0=no risk, 1=low risk)
Nutritional Assessment
- Anthropometry
- Biochemistry
- Clinical
- Dietary
- Environment
Anthropometry
Assessment of the different component parts of the human body (bone, muscle, water and fat)
Anthropometry - what is assessed
- Bodyweight
- Height
- BMI
- Skin fold thickness
- Mid upper arm circumference (MUAC)
- Mid arm muscle circumference (MAMC)
Biochemistry
Blood tests interpreted in conjunction with a clinical examination, previous medical history, and current medications.
Biochemistry - what is measured
- U&E’s (Na, K, Ca, Mg, PO4)
- FBC (Hb, RBC, WCC, Plts)
- Liver function tests (Alb, liver enzymes)
- CRP
- Micronutrients
- Glycated haemoglobin (HBA1c)
Clinical: how can diseases increase risk of malnutrition
Diseases may increase the risk of malnutrition through:
- Reduced intake
- Increased GI losses
- Increased demands.
Dietary
- Estimating energy requirements
- Fluid requirements
- Dietary assessment
Estimating energy requirements
Resting energy expenditure (REE) + Physical activity and diet-induced thermogenesis (PAL)
Resting energy expenditure (REE)
- Disease specific - varies between 20-25 kcal/kg
- BMI <18 (REE = 25-30 kcal/kg)
Fluid requirements - general
3L/day max for most patients
Fluid requirements - over 60
30ml/kg body weight
Fluid requirements - under 6
35ml/kg body weight
Fluid requirements - obese
- Use ideal body weight requirements
Fluid requirements - renal/cardiac failure
- Fluid requirements are lower
Other requirements
- 0.8-1.5g protein kg/day (0.13 - 0.24g nitrogen)
- Electrolytes (sodium, potassium, magnesium, calcium, phosphate)
- Carbohydrate vs lipid (fat)
- Vitamins and trace elements (micronutrients)
Dietary assessment
- Dietician
- Estimation of calorie intake
- No. of meals and snacks
- Balanced diet?
- Oral fluid intake
- Any additional nutrition supplements?
- Special diets, intolerances, food allergies
NICE CG32 (2006) - Definition of malnourished
- A BMI <18.5 kg/m2
- Unintentional weight loss >10% within last 3-6 months
- A BMI >20 kg/m2 and unintentional weight loss >5% within the last 3-6 months
NICE CG32 (2006) - Those at risk of malnutrition
- Have eaten little or nothing for more than 5 days and/or are likely to eat little or nothing for the next 5 days or longer
- Have a poor absorptive capacity and/or have high nutrient losses and/or have increased nutritional needs from causes such as catabolism
Refeeding syndrome
- Occurs when a person in a state of prolonged starvation is given nutrition.
- During refeeding, there is a sudden shift in fluid/electrolytes.
- Leads to potentially fatal shifts in fluids and electrolytes within the body
- Can be life threatening condition if not correctly managed
Shift in fluid/electrolytes results in:
- Insulin secretion
- Glycogen, fat and protein synthesis for which phosphate, magnesium and thiamine are required
- Increased uptake of potassium and magnesium into cells
High risk of refeeding (1)
One or more:
- BMI <16 kg/m2
- Unintentional weight loss >15% in last 3-6 months
- Little or no nutritional intake for > 10 days
- Low levels of potassium, phosphate or magnesium prior to feeding
High risk of refeeding (2)
Two or more:
- BMI <18.5 kg/m2
- Unintentional weight loss >10% in the last 3-6 months
- Little or no nutritional intake for > 5 days
- History of alcohol abuse or drugs including insulin, chemotherapy, antacids or diuretics
