Pulsitile Perfusion Final Exam

Question 1

MEAN pressure equation ?

Answer 1

Diastolic X2 + Systolic
__________________
3

Question 2

Why do most people fear the use of pulsatile perfusion ?

Answer 2

Fear of hemolysis,

shear stress = intimal damage

Question 3

Theoretical advantage that the production of pulsatile flow depends not on a pressure gradient, but on ?

Answer 3

an energy gradient

Question 4

EEP definition

Answer 4

(Energy Equivalent Pressure)

represents the energy content of the pulsatile arterial wave.

Question 5

Using the EEP formula, it was determined that the energy needed to deliver pulsatile flow was_____ that required to produce non-pulsatile flow for the same levels of mean pressure and flow.

Answer 5

up to 3.4 x

Question 6

capillary patency is preserved longer by ?

Answer 6

peaks of systolic pressure with a pulsatile pressure

Question 7

non-pulsatile flow produces what ?

Answer 7

microcirculatory shunting and reduced capillary perfusion

Question 8

Transition from pulsatile to non-pulsatile flow results in:

Answer 8

Marked increase in discharge frequency from baroreceptor in carotid sinus

This may initiate reflex neuroendocrine responses which remain operative throughout the non-pulsatile phase.

Question 9

Non-pulse flow is associated with progressive elevation in SVR
due to what ?

Answer 9

• Renin angiotensin activation that continues into the post CPB period

Question 10

Pulsatile perfusion is associated with significantly lower levels of vascular resistance, what are the benefits?

Answer 10

• Improved tissue perfusion

- Lower afterload for the ventricle at the end of the perfusion period

Question 11

Metabolic Effects of Pulsatile Flow at the cellular level ?

Answer 11

• higher rates of oxygen consumption and

- reduced metobolic acidosis

Question 12

enhanced energy from a pulsatile flow, may maintain microcirclatory patency and therefore ?

Answer 12

optimize tissue perfusion.

Question 13

Metabolic Effects of Pulsatile Flow at the organ level.

Kidney:

Hepatic:

Answer 13

Kidney: better urine output with pulse.

Question 14

Metabolic Effects of Pulsatile Flow at the organ level.

Brain:

Answer 14

• reduced cerebral acidosis

- reduced markers of brain injury

Question 15

Metabolic Effects of Pulsatile Flow at the organ level.

Hepatic, gut, pancreas:

Answer 15

Better function possibly because of reduction of mucosal ischemia which can induce endotoxemia

Question 16

Pump-head accelerates in systolic phase and

Answer 16

deaccelerates during diastole