CP11-8 Nutritional Support in Trauma Flashcards
What is the definition of trauma?
An injury or wound to living tissue caused by an extrinsic agent
What percentage of global mortality is caused by trauma?
9%
What are some potential features of physical trauma?
Bleeding (intravascular fluid loss)
Extra vascular volume increases
Tissue destruction
Obstructed/impaired breathing
Infection
Inflammation
Starvation due to metabolic changes
What changes due to trauma can cause shock?
Blood loss
Poor blood flow
Low O2 supply
What are the three phases of metabolic change following trauma?
Shock
Hypercatabolism
Anabolic phase
What is involved in the hypercatabolism phase after trauma?
Increase in basal metabolic rate
Increase in anaerobic metabolism
Excessive metabolic breakdown of fat and protein
What is involved in the anabolic phase following trauma?
Macromolecule synthesis
Onset of recovery including improved appetite and diuretics.
What most commonly causes immediate death after trauma?
Haematological shock
Brain injury
What most commonly causes early death after trauma?
Haemorrhage
CNS injury
What most commonly causes late death after trauma?
Infection
Multi-organ failure
How does loss of circulating volume affect the body?
Decrease in red cells = decrease in O2 causing cellular hypoxia, anaerobic metabolism and lactate accumulation
Decrease in white cells and immune response
Decrease in cardiac output, BP and organ perfusion
Decrease in energy substrate deliver to cells and tissues
After trauma what are the endocrine effects of pro inflammatory cytokines (IL-1 and TNF-alpha)?
Increase in catabolic hormones include ACTH (cortisol) and catecholamines (e.g. glucagon)
Decrease in anabolic hormone secretion including growth hormone and insulin
This decreases appetite
After trauma, how long can glucose stores in the body last without eating?
24 hours
What happens to the brain in states of stress?
It has no glycogen store so has to use ketones in place as an energy substrate
What is a danger in the catabolic phase?
Stress-induced hyperglycaemia and increased blood lactate - both reduce prognosis
What are some catabolic responses to trauma?
Glycogenolysis
Lipolysis and ketogenesis
Proteolysis and gluconeogenesis
How much glucose can be gained from a 1kg of muscle when the body is in a state of proteolysis?
Only 120g
How much nitrogen is lost on average per day when the body is in a state of proteolysis?
60-70 g/day
What are some qualitative protein changes after trauma?
Increase in inflammatory modulators and scavengers
Increased CRP
Increase haptoglobin
Increase in clotting factors
Decrease in albumin
What are some quantitative protein changes that can occur as a result of trauma?
Decrease in synthesis of protein
Decrease in skeletal protein
Decrease in structural protein
Decrease in secreted protein
How can unchecked proteolysis lead to death?
Causes life-threatening damage to essential structural and secreted proteins so can no longer prevent the development of infections like pneumonia for examples as can no longer cough to expel infection so retains secretions leading to inflammation.
How long does the anabolic phase after trauma usually last?
3-8 days
When does the anabolic phase after trauma happen?
Sometimes not until several weeks after severe trauma and coincides with beginning of dieuresis and request for oral intake.
What is a risk during the anabolic phase?
Reseeding syndrome risk
What is the obesity paradox?
People who are obese tend to do better after trauma as have more energy reserves
What is restored in the anabolic phase after trauma?
Body proteins
Nitrogen balance
Fat stores
Muscle strength
True or false - provision of adequate nutrition can reverse a hypercatabolic state?
False - strongly catabolic patients cannot achieve a positive nitrogen balance by nutritional intervention until the peak of the catabolic drive has passed, instead it is important to support vital functions, maintain electrolyt and fluid balance.
What is important to consider in nutritional support following trauma?
Timing
Route - enteral/parental
Constituents
Monitoring
When determining the constituents of nutritional support following trauma, what should be considered?
The demands of the hypermetabolic phase
Pre-trauma nutritional state
The amount of nitrogen lost
What will be lost by immobilisation
Refeeding syndrome
What is refeeding syndrome?
When a patient has been deprived of nutrition for so long that they are in starvation mode so upon refeeding will cause rapid uptake of glucose.
What are some consequences of malnutrition?
Negative nitrogen balance
Muscle wasting
Widespread cellular dysfunction - including infection, poor wound healing, changes in drug metabolism, prolonged hospitalisation and increased mortality.
What is the incidence of malnutrition in hospitalised patients?
50%
How do you nutritionally treat patients with CF?
With pancreatic enzyme replacement (Creon)
Nutritional supplements
Fat-soluble vitamins
High calorie diet
Ursodeoxycholic acid
What is the aim of nutritional treatment in CF patients?
Maintain body weight
Avoid catabolic state
Introduce peritoneal nutrition early when get sick
What is Wernicke’s-Korsakoff syndrome?
A thiamine (B1) deficiency affecting glycolysis, the citric acid cycle, synthesis of nucleic acids, neurotransmitters, formation of gluathione and steroids.
What drugs increase breakdown of thiamine?
Anti neoplastic drugs
Contraceptives
Diuretics
What is a consequence of acute B1 (thiamine) deficiency?
Wernicke encephalopathy
What is the classic triad that characterises Wernicke’s encephalopathy present in 17% of affected patients?
Encephalopathy, occulomotor dysfunction and gait ataxia
What is korsakoff syndrome?
Chronic B1 deficiency
What criteria is used to diagnose Wernicke’s encephalopathy?
What are symptoms of Wernicke’s encephalopathy?
What are symptoms of korsakoff syndrome?
How do you treat Wernicke’s encephalopathy?
What are risk factors for thiamine deficiency?
Alcohol dependency
Cancer chemotherapy
Anorexia nervosa
Bariatric surgery
Refeeding syndrome
What modulates the metabolic response to trauma?
Catecholamines
Hormones
Cytokines
