Cardiovascular responses to shock

Question 1

what are the three major different types of shock?

Answer 1

• hypovolaemic
• cardiogenic
• obstructive
• distributive

Question 2

what are examples of hypovolaemic shock?

Answer 2

haemorrhagic and non-haemorrhagic`

Question 3

what are examples of cardiogenic shock?

Answer 3

acute MI

Question 4

what are examples of obstructive shock?

Answer 4

cardiac tamponade, tension pneumothorax, pulmonary embolism, severe aortic stenosis

Question 5

what are the two types of distributive shock?

Answer 5

neurogenic

vasoactive

Question 6

what is an example of neurogenic shock?

Answer 6

spinal cord injury

Question 7

what is an example if vasoactive shock ?

Answer 7

septic shock, anaphylactic shock

Question 8

what is shock defined as?

Answer 8

an abnormality of the circulatory system resulting in inadequate tissue perfusion and oxygenation

Question 9

what two factors does adequate tissue perfusion depend on?

Answer 9

adequate blood pressure and adequate cardiac output

Question 10

what does CO depend on?

Answer 10

SV and HR

Question 11

what 3 factors impact SV?

Answer 11

preload, myocardial contractility and afterload

Question 12

what determines the preload?

Answer 12

venous return

Question 13

what is the sequence of events in hypovolaemic shock ?

Answer 13

1. Loss of blood volume
2. Decreased blood volume
3. Decreased Venous Return
4. Decreased End Diastolic Volume
5. decreased stroke volume
6. decreased CO and BP —>
7. inadequate tissue perfusion

Question 14

what causes cardiogenic shock?

Answer 14

sustained hypotension caused by decreased cardiac contractility

Question 15

what are the events leading to cardiogenic shock ?

Answer 15

1. decreased cardiac contractility —>
2. decreased SV - –>
3. decreased CO and BP —>
4. inadequate tissue perfusion

Question 16

what are the events leading to tension pneumothorax : obstructive shock?

Answer 16

1. increased intrathoracic pressure
2. Decreased Venous Return
3. Decreased End Diastolic Volume
4. decreased stroke volume
5. decreased CO and BP —>
6. inadequate tissue perfusion

Question 17

what are the events leading to neurogenic shock ?

Answer 17

1. loss of sympathetic tone
2. massive arterial and venous vasodilatation
3. decreased VR and TPR
4. decreased CO and BP —>
5. inadequate tissue perfusion

Question 18

what are the events leading to vasoactive shock ?

Answer 18

1. release of vasoactive mediators
2. massive venous and arterial vasodilatation - also increased capillary permeability
3. decreased VR and TPR
4. decreased CO and BP
5. inadequate tissue perfusion

Question 19

what are some general outlines of treatment of shock?

Answer 19

ABCDE approach
high flow oxygen
volume replacement

Question 20

what should be given for cardiogenic shock?

Answer 20

inotropes as they increase contractility

Question 21

what should be done for a tension pneumothorax?

Answer 21

immediate chest drain

Question 22

what should be done for anaphylactic shock ?

Answer 22

given adrenaline

Question 23

what should be given for septic shock?

Answer 23

vasopressors

Question 24

what are the haemorrhagic causes of hypovolaemia

Answer 24

trauma, surgery, GI haemorrhage

coughing up blood

Question 25

what are the non-haemorrhagic causes of hypovolaemia ?

Answer 25

vomiting, diarrhoea, excessive sweating

Question 26

compensatory mechanisms can maintain blood pressure until…… of blood volume is lost. At this point compensatory mechanisms start to fail

Answer 26

> 30%

Question 27

look at lecture

Answer 27

plz.

Question 28

in which organ is there a tight regulation of blood flow?

Answer 28

the cerebrum

Question 29

how is cerebral blood flow regulated?

Answer 29

through the myogenic response