Malnutrition

Question 1

What is malnutrition?

Answer 1

a state resulting from lack of uptake or intake of nutrition leading to altered body composition and body cell mass resulting in diminished physical and mental function and impaired clinical outcome from disease

Question 2

What is disease related anorexia?

Answer 2

loss of appetite from pathophysiological mechanisms and modification of central regulation of feeding behavior

Question 3

What is the cost of malnutrition in england per year?

Answer 3

19.6 billion

Question 4

How do we screen for malnutrition?

Answer 4

malnutrition universal screening tool - screen for adult malnutrition

IS NOT DIAGNOSIS

Question 5

What are the limitations of MUST?

Answer 5

miss malnourished populations ie in ascites

Question 6

What does MUST screen for?

Answer 6

risk for malnutrition based on BMI, unplanned weight loss and acute disease

Question 7

How is nutrition assessment done?

Answer 7

anthropometry
biochemistry 
clinical history 
nutrition requirements
social and physical state

Question 8

What is anthropometry?

Answer 8

measuring the physical measures of a persons size

ie scales, measuring circumference of arms etc, CT, hand grip strength etc

Question 9

Which patients need nutritional support?

Answer 9

malnourished = BMI less than 1.5
or unintentional weight loss greater than 10% original body fat across 3-12months
or bmi less than 20 with unintentional weight loss over 5%

risk of malnutrition = eaten little or nothing, have a poor absorptive capacity and/ or high nutrient loss or increased nutritional need from catabolism

Question 10

What is artificial nutritional support?

Answer 10

provision of enteral or parenteral nutrients to treat or prevent malnutrition

Question 11

What is enteral nutrition?

Answer 11

tube feeding

Question 12

What is parenteral nutrition?

Answer 12

intravenous delivery of nutrients, electrolytes and fluid into venous blood

Question 13

What are the complications of enteral nutrition?

Answer 13

pH greater than 5.5 needs to be followed up by a chest x ray examined by a professional

mechanical problems like misplacement, blockage and buried bumper

metabolic problems like hyperglycaemia or deranged electrolytes

GI problems like aspiration, nasopharyngeal pain, laryngeal ulceration etc

Question 14

When is parenteral nutrition prescribed?

Answer 14

an inadequate or unsafe oral or nutritional intake

or a non functioning, inaccessible or perforated gastrointestinal tract

Question 15

How does paraenteral nutrition given?

Answer 15

through central venous catheter - at the superior vena cava and right atrium

Question 16

What are complications associated with paraenteral nutrition?

Answer 16

mechanical - pneumothorax, haemothorax, thrombosis, arrythmia

metabolic - deranged electrolyte, hyperglycaemia, abnormal liver enzymes, oedema, hypertriglyceridaemia

catheter related infections

Question 17

What is albumin?

Answer 17

synthesised in the liver

Question 18

What is low albumin associated with?

Answer 18

poor prognosis

Question 19

What is meant by albumin being a negative acute phase protein?

Answer 19

decreased plasma albumin associated with increased inflammation

Question 20

What cytokines inhibit albumin synthesis?

Answer 20

interleukin 6 and tumour necrosis factor

Question 21

Why does albumin decrease with inflammation?

Answer 21

inflammatory stimulus leads to activation of monocytes and macrophages resulting in release of cytokines which downregulate production of albumin. degradation and transcapillary loss of albumin also increase during this state

Question 22

What is refeeding syndrome?

Answer 22

a biochemical shift and clinical symptoms occur in malnourished individual on reintroduction of oral, enteral or parenteral nutrition

Question 23

Outline the physiology behind starvation

Answer 23

during starvation there is reduction in insulin and glucagon and glycogen stores are used -> and metabolism shifts to use of ketones and decrease use of amino acid to spare skeletal muscle breakdown + decrease in basal metabolic rate -> loss of fat and decrease of potassium magnesium and phospahate, (serum concentration is retained) increase of sodium, intracellular and extracellular water + thiamine defienciency is likely

Question 24

Outline the physiology behind refeeding syndrome

Answer 24

1. reintroduction of carbohydrate creates secretion of insulin which needs to use the sodium potassium pump with magnesium as a cofactor
2. this drive influx of potassium and efflux of sodium and fluid from cells in extracellular space
3. carbohydrate and insulin secretion drives phosphate into cells as its required for energy storage as ATP
4. increased cellular uptake of glucose, potassium, magnesium and phosphate but reduced extracellular concentrates - hypokalaemia, hyponatremia
5. thiamine is coeznyme in carbohydrate metabolism
6. low electrolytes and thiamine resulting in refeeding oedema and other clinical manifestations

Question 25

When can thiamine deficiency occur?

Answer 25

refeeding in a vitamin B depleted patient

Question 26

What are symptoms of refeeding syndrome?

Answer 26

arrhythmia, tachycardia, heart failure, respiratory depression, ecephalopathy, coma, seizures, rhabdomyolysis, wernickes encephalopathy

Question 27

What are the criteria for defining risk of refeeding syndrome?

Answer 27

little or no food intake for more than 5 days

please check powerpoint slide or nice guidelines for full criteria

Question 28

How do we manage refeeding syndrome?

Answer 28

start 10-20kcal/kg
carbohydrates making 40-50% of energy, and provide micronutrients

correct and monitor electrolytes

administer thiamine

monitor fluid shifts and minimise risk of fluid and sodium overload

Question 29

When is pabrinex prescribed?

Answer 29

for thiamine deficiency especially with risk of refeeding syndrome

Question 30

What does thiamine deficiency result in?

Answer 30

beriberi - severe chronic thiamine deficiency

Question 31

What is a target stoma output after surgery?

Answer 31

less than 1.5L a day

Question 32

What urinary sodium value indicates dehydration?

Answer 32

less than 20mmol/L