Flashcards in Nutritional support in trauma Deck (30):
When does phase 1 occur? What is it? For how long?
2-6 hours after trauma, shock, for 24-48hrs
What does phase 1 involve release of?
Cortisol, catecholamines, cytokines
4 things that happen in phase 1
HR and respiratory rate increased, peripheral vasoconstriction, hypovolaemia
When does phase 2 happen, what is it called?
2 days after
3 things released in phase 2?
Cortisol (stimulated by ACTH)
5 things that happen in phase 2
Increased O2 consumption
Increased metabolic rate
Negative nitrogen balance (muscle broken down to AAs)
Phase 3 name and when?
Anabolic, weeks after (or 3-8 days after minor surgery) lasts for a few weeks/months
4 things that happen in phase 3
Normal nitrogen balance
10 affects of cytokines
cell adhesion proteins
catabolic (metabolic effect)
Acute phase proteins
T and B cell activation
Endocrine - stimualtes catabolism (catecholamines, cortisol, glucagon) and inhibits anabolism (GH and insulin decreased)
Brain obligate substrate?
How many mins of circulatory failure can the brain survive?
What does the CNS switch to metabolising in the absence of glucose?
What do the kidneys and liver metabolise?
Fatty acids and AAs
What does skeletal muscle metabolise?
Fatty acids and glycogen stores
If glucose and O2 supply interrupted, what 3 stages of metabolism occur?
1. glycogenolysis (glycogen to glucose) max 24hrs
2. gluconeogenesis (muscle to AAs to glucose and lactate)
3. lipolysis and ketogenesis (free fatty acids to acetyl coA to ketones (acetoacetate and hydroxybutarate)
Aerobic resp 1 mol glucose --> ? mol ATP?
Anaerobic resp 1 mol glucose --> ? mol ATP?
In an anaerobic response what happens to pyruvate?
Reduced to lactate
What is lactate a marker of?
Why proteolysis increased in trauma?
AAs needed to create inflammatory modulators and gluconeogenesis
What are markers of increased proteolysis?
Increased plasma ammonia, increased N2 loss in urine
Will adequate calories prevent muscle breakdown in trauma patients?
No, cytokine secretion stimulates muscle breakdown regardless
How might a trauma patient get pneumonia?
Muscle breakdown = respiratory muscle weakness
Increased lactate is a marker of?
What affect does immobilisation have on loss of substances?
Increases loss e.g. Ca, P, Mg
Is parenteral or gut-involved feeding better?
What is primary malnutrition?
Starvation or dietary deficiency of specific nutrients
What is secondary nutrition?
Nutrition present in adequate amounts but appetite suppressed/absorption failure/increased demand