Burn Flashcards
What is meant by transcellular fluids?
the fluid that fills up spaces, part of the extracellular fluid (24L intra-cellular, 18L extra-cellular):
- Cerebrospinal
- Synovial
- Aqueous humorous
- GI fluid
- pericardial
- intrapleural
- intraperitoneal
Why do elderlies have less water content?
As they lose muscles, which contain a lot of water more than fat
- As fat increases fluid decreases
What are the major electrolytes of the body?
1) ECF:
- Na+ (Sodium): 142
- Cl- (Chloride): 103
2) ICF:
- K+ (Potassium): 150
- HPO4- (Phosphate): 100
How do our cells keep a balance between Na+ & K+?
via the Na/K pump (active transport)
What are the major causes of fluid & electrolyte loss?
1) Vomiting and Diarrhoea
2) Hemorrhage
3) Burns; >20% of total body surface area (TBSA) of an adult and >10% in children
What are the phases the body goes through in a trauma?
1) EBB phase “24-48hrs” (low-flow):
- Decreased metabolic rate & reduced tissue perfusion, in the early shock phase characterized by:
- Decline in body temperature.
- Decrease in oxygen consumption
- Reduce energy expenditure
- Decrease in blood pressure
2) Flow phase (after the stabilization of the blood pressure and heart rate “weeks-months”):
- Catabolic phase, a phase of hypermetabolic rates, characterized by:
- Increase oxygen consumption (increase energy expenditure)
- Hyperglycemia, glycogenolysis, lipolysis, and proteolysis due to hormonal responses.
- Muscle protein degradation, -increased resting energy expenditures, -increased
risk for infection, increased risk for multi-organ dysfunction,
- Mediated mainly by catecholamines and corticosteroids (DOMINANT IN THIS PHASE)
3) Recovery phase:
- Anabolic phase
what is the main goal of the EBB phase?
To stabilize the patient and protect him from shock
The increase in infection rate during the flow phase is mainly due to what?
malnutrition
What causes the hemolysis of RBC in burn patients?
Circulating factors that are released during the time of burn injury and the thrombosis of burned tissue capillaries
How can a circulatory collapse happen in burn patients?
due to the fact that the permeability of BV increases albumin will start moving toward the ITF and the water will follow it, causing edema and hypovolemia in the BV
What happens in the capillary in a burn?
1) Hypovolemia: moving of the fluid to the interstitial fluid
2) Hyperkalemia: Direct cell injury releases K+, which will be exchanged with H+ in (metabolic acidosis “If the blood pH became low H+ will enter the cell in exchange with K+ which will return the pH to normal but cause hyperkalemia”)
3) Hypo/hypernatremia:
- Na+ homeostasis is regulated, during the Ebb and Flow phases of the burn
- In Ebb, sodium retention
- In the flow phase, increases sodium excretion due to improved renal function and the catabolic state
What is the cause behind metabolic acidosis?
- It is the accumulation of H+ inside the cells
Due to:
1) Early sympathico-adrenergic effect that causes vasoconstriction and thus renal impairment
2) The increase in oxygen demand which will cause cellular hypoxia and accumulation of lactic acid
What is meant by the anion gap?
It is a measure of the difference between the major anions and cations, which can diagnose metabolic acidosis from respiratory acidosis equated by:
Anion Gap (AG) = (Na+ + K+) - (Cl- + HCO3-)
- In metabolic acidosis, the bicarbonate levels go down increasing the anion gap
- The higher the AG the more acidic
- Normal anion gap is between 15-20 milliequivalent per liter
How is carbohydrate metabolized during stress?
Hyperglycemia (due to the increase in glucose production and reduction in glucose utilization), facilitated by catecholamine, glucagon, and cortisol which promotes glycogenolysis and gluconeogenesis
- Insulin secretion is downregulated by catecholamines
How are proteins metabolized during stress?
At first, there is an inhibition of protein anabolism, followed by catabolism (stimulated by cortisol), releasing essential amino acids
