Nutrition in Medicine Flashcards
What is undernutrition?
A form of malnutrition resulting from reduced supply of food or inability to digest/assimilate and utilise the necessary nutrients
What are the 2 classes of nutrients?
Macronutrients
Micronutrients
Who is most vulnerable to undernutrition?
Chronically diseased elderly recently discharged from hospital low income socially isolated
What are the consequences of undernutrition?
In the community - falls (weak bones from undernutrition), depression (symptoms of depression is loss of appetite - viscous circle), infection risk (immunodeficient as little energy), dependency
In hospitals - increased morbidity, length of stay, dependency, mortality and costs of care
What are some causes of reduced nutritional intake?
anorexia side effects of treatment pain dysphagia physical disability nil by mouth (should not eat for a period of time)
What are some causes of increased nutritional requirements?
inflammation/infection
pyrexia
tissue healing
metabolic effects
What are some causes of increased nutritional losses?
malabsorption
would exudate/burns
What are the consequences of undernutrition?
decreased muscle mass, decreased visceral proteins, impaired immune response, impaired wound healing and response to trauma, multiple organ failure,
fatigue, lack of initiative, bedridden, apathy, depression, behavioural changes, complete exhaustion
(if ill these things will happen faster)
How can we assess nutritional status?
- history: weight and BMI, diet history, weight changes, appetite/taste changes, GI symptoms, energy and activity levels
- physical: muscle wasting, fat stores, ascites, oedema
What specific clinical investigations regarding nutritional assessment can we do?
- clinical anthropometrics (skinfold thickness -fat, mid upper arm circumference - muscle)
- imaging procedures (DEXA)
- bioelectrical impedence analysis
- handgrip dynamometry
How can you do a nutritional assessment in the lab?
Check albumin/transferrin/pre-albumin/retinol binding protein (for anaemia and plasma proteins)
Check vitamin & mineral concentrations
Check lymphocyte count/delayed hypersensitivity reaction for immune response
What is total energy expenditure made up of?
- basic metabolic rate
- thermic effect of food (energy required to process food)
- physical activity
- stress factors (if they are ill for example)
How do you estimate volume requirements?
- non urinary output (stoma, fistula)
- insensible loss (sweat) and add 10% for every degree Celsius temperature rise
- 1-1.5L urine daily
What nutritional support should be given and at what stage?
early levels for the majority:
increased intake of normal diet
prescribed supplements
specialist enteral feeds (via mouth to the stomach as patients cannot eat themselves)
nasogastric tube
gastrostomy tube (through abdominal wall)
parenteral nutrition (IV directly into bloodstream)
What are some indications for gastrostomy feeding?
- reduced consciousness (brain injury)
- unsafe swallowing (Parkinsons, motor neurone disease, CVA)
- pre head and neck cancer surgery/radiotherapy
- special situations (cystic fibrosis)
(through abdominal wall, use endoscope)
What are some indicates for parenteral nutrition?
Prolonged postoperative ileus Intestinal obstruction - ongoing Short bowel Small bowel fistula Acute pancreatitis GI motility disorders
How is parenteral nutrition carried out?
Calculate nutrient need Compound in a large IV bag Usually central vein access Pump infusion 24-10 hours ASEPSIS ASEPSIS Monitor especially Water and Electrolytes Stop when Enteral working
What are the problems with nasogastric feeding?
aspiration, discomfort, diarrhoea
What are the problems with percutaneous endoscopic gastrostomy?
peritonitis, infection, discomfort, diarrhoea
What are the problems with parenteral nutrition?
infection, thrombosis, electrolyte disturbances, hepatic dysfunction, hyperglycaemia
What are some causes of disease-related undernutrition?
Reduced nutritional intake
Increased nutritional losses
increased nutritional requirements
What is nil by mouth?
Someone who cannot eat anything because of : operations, investigations, certain treatments and drugs
What is MUST?
Malnutrition Universal Screening Tool
Measure weight and BMI
Decide if they have lost weight
Give each a score
If 1 or below -> don’t need to take action
If score 2 or above -> take to dietician
Happens in every hospital in the UK and every week after that according to NICE guidelines
What is basic metabolic rate?
Energy required to run the basic metabolic systems
Can be estimated based on individual’s information
What are the protein requirements?
- 75g/kg/day for healthy adults
52. 5g/day for 70kg
