Cerebral Blood flow

Question 1

What component of the cranial vault are you most likely to adjust?

Answer 1

Cerebral spinal fluid

Question 2

How do you calculate CPP?

Answer 2

change in pressure = MAP - ICP

Question 3

How is cerebral blood flow regulated?

Answer 3

Local and neural mechanisms

Question 4

How do local mechanisms effect cerebral blood flow?

Answer 4

Helps keep CBF constant over wide range of arterial pressures (metabolic and myogenic)

Question 5

How does the SNS serve as a protective mechanism with increased CBF?

Answer 5

Constrict to prevent high systemic pressure transmission to cerebral arteries (prevent stroke, edema)

Question 6

At what point is the CNS ischemic response activated when considering MAP?

Answer 6

Not activated until MAP <60

Question 7

What produces and releases CSF into ventricles?

Answer 7

Choroid plexus

Question 8

Where does the CSF drain into circulation?

Answer 8

Arachnoid villi into the sagittal sinus which drains into the venous system

Question 9

What can occur if the arachnoid valves are blocked or there is an increase in CVP?

Answer 9

There will be an increase in ICP as CSF backs up

Question 10

What two mechanisms can be manipulated in order to compensate for an increase ICP?

Answer 10

Decrease CFS

Decrease cerebral volume (vasoconstriction of vessels)

Question 11

What structure provides a protective design in cerebral circulation?

Answer 11

Circle of Willis

Question 12

What causes bradycardia in cushing’s triad?

Answer 12

Baroreceptors are stimulated and causes a decrease in HR via PSNS