Week 2 Revision Flashcards
How many L of the body of water?
40L (60%)
What is the systemic response to surgey?
To preserve fluid balance, blood volume and blood pressure
What are the 3 stages of responsde to surgery?
Stage 1 - fluid retention & catabolism
Stage 2 - diuresis
Stage 3 - anabolism
Explain how fluid loss is reduced by the renin-aldosterone-angiotensin system
1) the liver produces angiotensiogen
2) angiotensiogen is converted by renin to angiotensiogen 1
3) it then travels through the lungs and is converted to angiotensiongen 2 by converting enzymes
4) this is then converted in adrental cortex to release aldosterone which causes the reabsorpotion of the sodium; which then reduces fluid loss
Explain 3 functions of angiotensiongen 2
1) Vasopressin (enocurges the kidney to keep water, reduction of urine output)
2) Makes you thirsty (this will then increase fluid intaek, increasing blood flow)
Why will the renin-aldosterone-angiotensin system be activated? Give 3 reasons
- If sodium chloride levels drop
- Reduction in blood volume
- BP goes down
Why do you want to avoid surgical stress?
Fluid balance and BP will go crazy
List 4 immediate or early post operative complications?
- Haemorrhage
- Low urine output (AKI and dehydration)
- DVT (due to the lack of mobilisation)
- Acute confusion
What is shock?
Very suddenly the circulation of blood has a stopped flowing
What are the five types of shock? Explain
Cardiogenic – cardiac function (the heart) is not pumping effectly – mainly caused by a heart attcack. If the ehart is not piumping no blood getting aorund the body
Sepsis – caused by a body wide infection, you get vasodilation. BP drops
Anaphylasctic – huge vasodilation – you have a wide spread hyposensitivy reaction leading to wide spread vasodilation
Neurogenic – some damage above T6 in the spinal cord. Damage to the top of the spinal. Huge vasodilation. Huge trauma – RTC, a big fall
All these have no reduction in blood flow
Hypovolaemic shock – low volume of blood. Major reseason is because of bleeding
How much of blood loss will cause:
1) major threat
2) clinical shock but can be treated, is not life-threatening
3) severe, irreversible shock
1) 10% or less
2) 20-30%
3) 30-40%
What is hypovolaemic shock? What are 4 possible causes?
- Acute loss of 15-20% of blood volume (losing whole blood)
- haemorrhage (loss of whole blood)
- Burns (loss of plasma)
- large swetting
- emesis (vommiting)
What are the two stages of shock? Explain
1) compensation - the body is trying to help to do something about the loss of blood volume
2) decompensation - the shock has gone too far that it can not be help
How do you work out the cardiac output?
Heart rate x stroke volume (average 70mls)
What is peripheral resistance?
The resistance the blood encounters in the blood vessels (friction)