Trauma and Nutrition Flashcards
Define: Trauma
Injury or wound to living tissue- caused by extrinsic agent.
What are the three main consequences of fracture/internal injuries?
> Immune defence penetration
Blood loss
Impaired breathing
Which of these four has the highest mortality immediately after trauma? A) Multi-organ failure B) Acute Respiratory Distress Syndrome C) Head Injury D) Haematological Shock
C = Head injury.
Define: Shock
Low blood perfusion to tissues.
What is interrupted to tissues in shock?
> Substrate supply
> Metabolite removal
Phase 1 Clinical Shock:
1) What is secreted?
2) How long does it last?
3) When does it develop?
1) Catecholamines, Cortisol, Cytokines
2) 24-48 hours
3) 2-6 hours after trauma
What are the clinical effects of Phase 1 clinical shock?
1) Peripheral vasoconstriction
2) Hypovolaemia
3) Increased BP
4) Increased respiratory rate
What are the primary aims of Phase 1 shock?
> Stop infection
> Stop bleeding
Phase 2 Catabolic state:
1) What is secreted?
2) When does it develop?
1) Catecholamines, Glucagon, Cortisol
2) 2-6 days after trauma
What are the primary aims of Phase 2 shock?
1) Avoid sepsis.
2) Provide adequate nutrition.
Phase 3 Anabolic state:
1) When does it occur ?
2) What events does it coincide with?
1) 3-8 days after surgery or weeks after trauma.
2) Diuresis and oral intake request.
What are the clinical effects of Phase 3 Anabolic state?
> Body protein synthesis
Muscle strength
Normal nitrogen balance
Fat stores replenish.
What is released from the capillary during systemic capillary leak?
H2O, NaCl, Albumin and energy substrates
What are the catabolic hormones secreted by cytokines?
> Glucagon
ACTH
Catecholamines
What are the anabolic hormones inhibited by cytokines?
> Growth hormone
> Insulin
What is oxidised in normal metabolism?
Dietary carbohydrates, lipid and protein.
How long can glycogen stores maintain glucose levels for in health?
Up to 24 hrs
What does the brain do if it cannot use glucose as an energy substrate?
Uses ketones.
What can the liver and kidney do for energy substrates?
Do gluconeogenesis –> Can survive for hours without glucose
What substrates do the liver and kidney use?
> Fatty acids
> Amino acids
What substrates does skeletal muscle use?
> Glycogen stores
> Fatty acids
What are the 3 stages of when glucose and oxygen supply are interrupted?
> Glycogenolysis
Gluconeogenesis
Lipolysis and Ketogenesis
What occurs in Glycogenolysis?
Glycogen –> Glucose
What occurs in Gluconeogenesis?
Amino acids –> Lactate + Glucose.
Skeletal + secreted protein breakdown.
How much glucose can 1kg of muscle make?
120g glucose
How much Nitrogen can be lost per day in Gluconeogenesis?
~60-300g
What occurs in Lipolysis?
FFA –> Acetyl CoA –> Acetoacetate + Hydroxybutate
Why do ketones cause diuresis?
They are acids.
How many moles of ATP are made in Aerobic metabolism?
36 moles
How many moles of ATP are made in anaerobic metabolism?
2 moles
What is the process that leads to lysosomal enzyme release in Anaerobic metabolism?
ATP loss –> Loss of Na+/K+ –> Cellular swelling + membrane integrity loss –> Lysosomal enzyme release.
What are the pH, lactate and H+ levels in Lactic Acidosis?
pH = 60 nmol/L Lactate = > 5mmol/L
What does protein turnover aim to do?
> Maintain muscle mass
> Maintain plasma protein levels.
How does normal protein turnover maintain plasma protein levels and muscle mass?
By balancing skeletal muscle proteolysis with new protein production.
What occurs more in trauma protein turnover?
A) Skeletal muscle proteolysis
B) New protein synthesis
Skeletal muscle proteolysis
What occurs in skeletal muscle proteolysis?
> Increase in free amino acids –> liver for gluconeogenesis + protein synthesis
Increased ammonia in plasma
Increased N2 loss
Why won’t administrating lipid/carb calories stop muscle wasting in trauma/sepsis patients?
Their muscle wasting not due to lack of calories but bc of catabolic effects of cytokines.
Why is lactate produced in hypoxia?
Pyruvate not used in TCA cycle, instead –> lactate.
Anaerobic metabolism stops when lactate = toxic.
Why is lactate used as a trauma prognostic marker?
Failure of lactate to return to normal after trauma resuscitation.
Above what level of Blood lactate mmol/L is mortality 100%?
> 5mmol/L
What is the cycle that continues anaerobic glycolysis?
> Hypoxia –> Mitochondrial failure
Decrease oxidative phosphorylation
NADH > NAD+
Anaerobic glycolysis continues.
What two things should be considered before nutritional support is given?
> Hypermetabolic phase demands
> Pre-trauma nutritional state
When does Nitrogen loss peak?
4-8 days
From where is ~60-70g of nitrogen lost?
Long bone
How is up to 300g of nitrogen lost?
Severe bones
What does immobilisation increase the loss of?
Calcium, Magnesium, Phosphate.
What is Primary Malnutrition?
> Starvation - Inadequate intake of protein/calories
> Special nutrient deficiency
What is Secondary Malnutrition?
> Enough amount of nutrients but suppressed appetite
Enough amount of nutrients but inadequate aborsoption/utilization
Increased nutrient demand.
What is refeeding syndrome (Step by step) ? (HARD)
Hint: Catabolism to Anabolism
1) Starvation/Malnutrition
2) Glycogenolysis –> Gluconeogenesis –> Lipolysis and Ketogenesis
3) Depletion of vitamins, minerals, electrolytes.
4) Refeed - Minerals, Vits etc
5) Insulin secretion
5) Hypokalaaemia, Hypophosphataemia, Hypomagnaesemia etc
Where does CTFR gene localise to?
Secretory and Absorptive epithelial cells apical membrane within: > Pancreas > Liver > Intestine > Vas deferens > Sweat glands
What is CTFR protein function?
Regulate free flowing mucus
> Allow macromolecule (digestive enzymes for e.g) mov’t
> Lubes airways and ducts
> Protect airway, digestive and report lining
How does lung disease occur in CF?
1) Bacteria invade
2) Neutrophil accumulate
3) Release elastase –> digest lung protein –> damage tissue
4) Dead neutrophil release DNA
5) Cause mucus viscosity increase
How does GI disease occur in CF?
> Birth meconium ileum
Hepatobiliary disease - can’t metabolise lipids, steroid hormones, drugs and toxins
Pancreatic cysts - Diabetes. Low lipase and low protease
What is Resp CF treatment?
> Exercise > Nebuliser > Physio > Bronchodilator > Steroids > Mucolytics (DNase)
What is GI CF treatment?
> Creon- Pancreatic enzyme replacement > High Kcal diet > Ursodeoxycholic acid > Fat-soluble vitamin > Nutritional supplement
