Lecture 10 Arterial and Venous Systems and Lymphatics Flashcards
What are some of the factors that increase lymph flow, and also interstitial fluid pressure?
Elevated capillary hydrostatic pressure
Decreased plasma colloid osmotic pressure
Increased interstitial fluid colloid osmotic pressure
Increased permeability of capillaries
How do you calculate the rate of lymph flow?
Rate of Lymph Flow =
interstitial fluid pressure x activity of lymphatic pump
True or False:
Lymph vessels posses 1-way valves similar to veins.
True
At what condition does lymph flow reach its maximum?
When interstitial pressure rises slightly above atmospheric pressure.
The least amount of damping of the pressure pulses would occur in which of the following components of the circulatory system?
a) femoral artery
b) arterioles
c) capillaries
d) venules
a) femoral artery
Which of the following factors affect pulse pressure?
a) vascular elastance
b) arterial compliance
c) stroke volume
d) all the above
e) B and C only
e) B and C only
Which of the following is the most important means for the exchange of substances between the blood and the interstitial fluid?
a) blood hydrostatic pressure
b) capillary oncotic pressure
c) diffusion
d) interstitial fluid hydrostatic pressure
e) osmosis
c) diffusion
What is the definition of vascular distensibility?
Vascular distensibility -> (increase in volume) /(increase in pressure) X (original volume)
What affect does increasing the pressure in a vessel have on the vascular distensibility?
Increasing pressure would decrease vascular distensibility.
Does vascular distensibility increase or decrease when volume increases?
The vascular distensibility will increase.
True or False:
Pulmonary artery distensibility are about 6 times that of systemic arteries.
True
Fill in the Blank:
Pulmonary vein distensibilities are about the _________ as for systemic veins.
same
**Thus, pulmonary and systemic veins have about the same distensibility.
How much more distensible are veins than arteries?
8 times more distensible
What does capacitance describe?
Capacitance describes the distensibility of blood vessels.
The formula for vascular compliance = increase in volume / increase in pressure. What does vascular compliance tell us?
That the total quantity of blood (ml) that can be stored in a given portion of the circulation for each mmHg rise in pressure.
Fill in the Blank:
Capacitance (ml/mmHg) is __________ proportional to elastance.
Inversely
What is compliance equal to?
compliance is equal to distensibility X volume
True or False:
Capacitance is inversely proportional to volume and directly proportional to pressure.
FALSE - capacitance is directly proportional to volume and inversely proportional to pressure.
Fill in the Blank:
_________describes how volume changes in response to a change in pressure.
Capacitance
Is capacitance much greater for veins or arteries?
Capacitance is much greater in veins.
True or False:
Capacitance of arteries decreases with age.
TRUE
What is the relationship between elastic tissue, elastance, and compliance?
The greater the amount of elastic tissue in a blood vessel, the higher the elastance and the lower the compliance.
What does compliance measure?
Compliance is a measure of the ease with which a hollow viscus may be distended.
*example: volume change resulting from the application of a unit pressure differential between the inside and outside of the viscus; the reciprocal of elastance.
What does vascular compliance tell you?
Total quantity of blood that can be stored in a given portion of the circulatory system.
What is elastance a measure of?
The tendency of a hollow viscus to recoil toward its original dimensions upon removal of a distending or collapsing force.
A systemic vein is about eight times as distensible as its corresponding artery and has a volume about three times as great. How would the systemic vein’s compliance compare to that of a corresponding artery?
Compliance = (8) x (3) = 24
Study figure 15-1 from the book.
Guyton and Hall
How do you calculate pulse pressure?
pulse pressure = stroke volume / arterial compliance