Cardiovascular control

Question 1

Basic equation of flow and pressure

Answer 1

Mean arterial bp = cardiac output X peripheral resistance

Question 2

Carfiac output

Answer 2

CO = HR X SV

Question 3

Factors controlling cardiovascular flow and perfusion pressure

Answer 3

Frank-starling mechanism
Lung reflexes (sinus arrythmia)
Baro-receptor reflex
Bainbridge reflex
Chemoreceptor reflex
Local metabolites

Question 4

Frank-starling mechanism

Answer 4

Stroke volume of the heart increases with end-diastlic pressure, ie blood volume. Bigger strech on heart musvles causes bigger contraction, larger stroke volume.

Question 5

Baro-receptor reflex

Answer 5

Helps regulate short term blood pressure
Detects strech in auricles of the heart and carotid arch
Decreased stretch gives decreased activation which increases HR to restore bp.

Question 6

Bainbridge reflex

Answer 6

Increased central venous pressure, due to increased blood volume, increases HR.