Ch 8 - Metabolism and Nutritional Needs

Question 1

List the adverse consequences of protein-energy malnutrition

Answer 1

• Impaired cell mediated and humoral immunity
• Increased susceptibilty to infection and shock
• Delayed wound and fracture healing
• Increased wound dehiscense and leakage
• Poor tolerance to chemotherapy and radiation therapy
• Cardiac, skeletal and smooth muscle weakness
• Organ failure and death

Question 2

What is the primary energy source during uncomplicated starvation?

Answer 2

Fatty acids and eventually ketones

Question 3

How does the liver work to maintain glucose concentration within the blood during periods of fasting

Answer 3

Gluconeogenesis and glycogenolysis

Question 4

What is the cause of death durnig uncomplicated starvation?

Answer 4

Repsiratory and cardiac failure and bronchopneumonia

Question 5

How are the effects of starvation different in the ill/injured patient?

Answer 5

• Metabolic rate is increased
• Protein conservation does not occur
• Sympathetic nervous sys activation, increased catecholamines, glucagon, glucocorticoids, increased ADH, activation of RAAS
• Above neuroendocrine changes result in rapid development of malnutrition

Question 6

What is the main concern of lack of oral intake of nutrients?

Answer 6

Villous atrophy
Compromise of the intestinal epithelial barrier

Enteral feeding should begin within 48hr as this has been shown to decrease mortality in humans

Question 7

Describe the nutritional assessment phase based on the Circle of Nutrition as recommended by the Americal College of Veterinary Nutrition

Answer 7

Three sets of factors are assessed
- Animal-specific factors
- Diet-specific factors
- Feeding management and environmental factors

Question 8

What is considered optimal body fat content?

Optimal BSC?

Optimal muscle condition score?

Answer 8

• Optimal body fat 15-25%
• Optimal BCS 2.5-3/5 or 4-5/9
• Muscle condition has been proposed as a 3-point scale. 3 is considered ideal, any lower indicated a degree of sarcopaenia

Question 9

What haematalogical/biochemical abnormalities can be seen with malntrition?

Answer 9

Hypoalbuminaemia, lymphopaenia and anaemia (all non-specific)

Question 10

What are the 2 commonly used formulas to calculate RER

Answer 10

• RER (kcal/day) = 30BW + 70
• RER (kcal/day) = 70BW^0.75

Second equation is preferred as RER and BW are not linearly related

Question 11

How does severe injury or head trauma effect the energy requirements of the patient?

Answer 11

These patients have increased energy requirements due to the extent of the injuries or due to activation of the sympathetic nervous system. May exceed 2xRER

Protein requirements are increased to facilitate, recovery, immune function and wound healing. May exceed normal requirement for 50-100%

Question 12

What is the recommended protein intake for adults dogs and cats for maintenance

Answer 12

• Dogs = 2.62-3.28g/BW^0.75
• Cats - 3.97-5.9g/BW^0.75

Question 13

What is the most essential nutrient?

What is the recommended daily intake?

Answer 13

Water
50-60ml/kg/day

Question 14

What are the benefits of fat in a diet?

Answer 14

Increases the palatability and the calorie density

Should make up around 20-30% of the total energy requirements (8-10% on a dry matter basis)

Diets MUST contain essential FAs i.e linoleic acid is essential in a dog’s diet (arachidonic acid in a cat’s diet)

Question 15

When are carbohydrates required in a dogs diet?

Answer 15

During gestation and in sprinting Greyhounds

Dogs can maintain normal glucose levels and tissue glycogen on a no-carb diet. However pet food usually contain 40-60% carbs on a DM basis

Question 16

What is the role of protein in the diet?

Answer 16

Structure and function, and to a lesser extent energy

Supplementing diets with AAs can aid in protein synthesis and prevent atrophy

Question 17

What is carnitin? What function does it serve?

Answer 17

A quaternary ammonium compound. It is a cofactor for transport of long chain FAs across mitochondrial membrane to liberate energy

In dogs it has been shown to improve function and energy metabolism in muscle and may be useful in rehab

Question 18

List some pharmacological agents which can be used for appetite stimulation

Answer 18

• Mirtazapine
• Maropitant
• Benzodiazepines
• Cyproheptadine
• Anabolic steroids

Question 19

Define polymeric and monomeric diets

Answer 19

• Polymeric - Contain high molecular weight protein, carbs and fat and require digestion prior to absorption. Tend to be iso-osmolar
• Monomeric - Contain proteins in the form of AAs and peptides, carbs in the form of oligosaccharides and monosaccharides and fat in the form of medium-chain triglycerides. Do not require digestion. Tend to be hyperosmalar. Typically used with enterostomy tubes but can be used with anu feeding

Question 20

List some indications for parenteral nutrition

Answer 20

• GIT not functioning or complete rest is requires
• Unable to tolerate anaesthesia

Question 21

What products are within parenteral nutritiona solutions?

Answer 21

• Dextrose (if >10%, must be administered in a central vein)
• AAs (+/- electrolytes) (If >6.5% must be central)
• lipid emulsions (iso-osmotic) - Does not contain arachidonic acid whihc is essential for cats
• multivitamin and mineral support
• VitK must be given SQ - 0.5mg/kg on day 1 and then weekly)