Lecture 22: Circulation and Hemodynamics Part II

Question 1

What are the two types of pressure found in capillary wall that deal with moving fluids in and out of vessels?

Answer 1

Hydrostatic Pressure

Osmotic Pressure

Question 2

What do hydrostatic pressures deal with?

Answer 2

Pushing fluid out

Question 3

What do osmotic pressures deal with?

Answer 3

Pulling fluid out

Question 4

What is Starling Equation?

Answer 4

Jv = Kf[(Pc - Pi) - (πc - πi)

Question 5

If the Starling equation gives a positive value, what does that mean?

Answer 5

Net movement of fluid leaving capillary

Question 6

If the Starling equation gives a negative value, what does that mean?

Answer 6

Net movement of fluid entering capillary

Question 7

Heart failure can change what part of the Starling equation?

Answer 7

Pc

Question 8

Restricted lymphatic flow can change what part of the Starling equation?

Answer 8

Pi

πi

Question 9

Decrease in albumin can change what part of the Starling equation?

Answer 9

πc

Question 10

Inflammation can change what part of the Starling equation?

Answer 10

πi

Question 11

If blood pressure is elevated, what happens to the arterial walls under myogenic control?

Answer 11

Vasoconstriction

-tries to limit blood entering and prevent stretching of arterial walls

Question 12

What is active hyperemia?

Answer 12

Increase in blood flow

• due to increase of metabolites
• reduction of oxygen

Question 13

What is reactive hyperemia?

Answer 13

Increase in blood flow that occurs following a brief period of ischemia
-Sitting on hand for long period of time and then allowing a bunch of blood to enter after hand is free

Question 14

What is shear?

Answer 14

Stress on arterial walls due to increase in blood flow

-the increase shear stress can cause release of NO and further cause more vasodilation

Question 15

Does histamine and bradykinin cause vasodilation or vasoconstriction?

Answer 15

Vasodilation

Question 16

Does serotonin cause vasodilation or vasoconstriction?

Answer 16

Vasoconstriction

Question 17

Coronary and cerebral circulation is largely under what control?

Answer 17

Metabolic control

-don’t want coronary flow to vasoconstrict when SNS is active

Question 18

Where are the highest pressures of the pulmonary vascular system found?

Answer 18

Right ventricle

Pulmonary artery

Question 19

Why is there vasoconstriction when there is alveolar hypoxia?

Answer 19

Don’t want to increase blood flow to parts of lungs that do not properly work

Question 20

Why does the pulmonary blood flow have significantly less pressure and resistance compared to systemic circulation?

Answer 20

Pulmonary vasculature much more complaint

• easier to dilate arteries
• easier to reduce resistance

Question 21

How does the shunt pathway help vasculature in skin?

Answer 21

Helps remove heat and metabolic waste from skin

Question 22

What is the right to left shunt?

Answer 22

Systemic veins –> systemic arteries

• does not pass functional lung tissue
• example: fetus blood goes from RV to LV

Question 23

What is the left to right shunt?

Answer 23

Systemic arteries –> systemic veins

• does not pass functional lung tissue
• example: skin