L17-Shock and haemorrahage

Question 1

What is shock?

Answer 1

A state of inadequate perfusion of the body

Question 2

What is cardiogenic shock?

Answer 2

Due to any sort of pump failure but often due to myocardial infarction, arterial pressure falls and central venous pressure rises.

Question 3

What is bainbridge reflex and where are the volume receptors for this reflex?

Answer 3

They are in the right atrium of the heart and when they detect increased volume then they decrease sympathetic activity to the kidney that increases renal perfusion and they also decrease ADH release from the kidney so volume is decreased.

Question 4

Which are faster reflexes the baroreceptor reflex or the volume receptor reflex?

Answer 4

Baroreceptor reflexes are much faster than the volume receptor reflexes which take a long time to take effect.

Question 5

What are the most common cause of hypovolaemia

Answer 5

Haemorrhage
Diarrhoea and vomiting
burns
Dehydration

Question 6

What are the consequences of haemorrhage on the kidneys?

Answer 6

Lack of tissue perfusion causes a switch to anaerobic respiration that produces lactic acid
Damaged tissues release K+
Kidney has to deal with these whilst dealing with renal hypoxia

Question 7

What is one of the first renal responses to shock?

Answer 7

ADH is released which causes transient hyponatraemia as there is water retention, this hyponatraemia causes aldosterone release that increases sodium and water reabsoption.

Question 8

What is a colloid?

Answer 8

A large molecule that remains within the intravascular space when injected.

Question 9

When is a transfusion given instead of fluids?

Answer 9

Only when haemoglobin is very low

Question 10

What are crystalloids?

Answer 10

Fluids such as saline that is close to the concentration of the blood