Arteriole and Venous Systems and Lymphatics Flashcards
What is the equation demonstrating distensibility?
Vascular distensibility = increase in volume/ increase in pressure x original volume
True or false. Arteries are more distensible than veins.
False. Veins are about 8 times more distensible than arteries. The same is true for pulmonary veins.
True or False. Systemic arteries are more distensible than pulmonary arteries.
False. Pulmonary artery distensibilities are 6 times that of systemic arteries
What is the equation demonstrating vascular compliance (capacitance)?
vascular compliance (capacitance) = increase in volume/increase in pressure also….. compliance = distensibility x volume high compliance = high distensibility This is sort of a description of how easily a vessel can stretch when volume is increased
What term describes the total quantity of blood that can be stored in a given portion of the circulation for each mmHg rise in pressure.
Vascular compliance (capacitance)
True or False. Capacitance is inversely proportional to elastane.
True.
Increasing volume has what effect on capacitance?
Increasing volume causes capacitance to increase because they are directly proportional.
Increasing pressure has what effect on capacitance?
Increasing pressure causes capacitance to decrease because they are inversely proportional.
Which vessel has higher capacitance, veins or arteries?
Veins have greater capacitance than arteries.
Does capacitance increase or decrease as the human body ages?
The capacitance of vessels decrease as we age.
What effect does elastic tissue in a vessel have on elastance and compliance?
An increase in elastic tissue in a blood vessel increases the elastance and decreases compliance.
What is the definition of compliance?
Compliance is a measure of the ease with which a hollow viscus may be distended; i.e. the volume change resulting from the application of a unit pressure differential between the inside and outside of the viscus; is the reciprocal or elastance.
When does lymph flow reach maximum?
Lymph flow reaches maximum when interstitial pressure rises slightly above atmospheric pressure.
What are 4 factors that increase lymph flow?
1)elevated capillary hydrostatic pressure 2)decreased plasma colloid osmotic pressure 3)increased interstitial fluid colloid osmotic pressure 4)increased permeability of capillaries all of these favor fluid movement into the interstitial, thus increasing interstitial fluid volume, interstitial fluid pressure, and lymph flow at the same time.
What is the equation for rate of lymph flow?
rate of lymph flow = interstitial fluid pressure x activity of lymphatic pump.
Describe the structure of the lymphatic capillaries.
(add picture on slide 57 of the lymphatic capillaries) This picture shows that endothelial cells of lymphatic capillaries are anchored by anchoring filaments to the surrounding connective tissue. The endothelial cells somewhat overlap each other forming valves. It is also important to note that when interstitial spaces swell it stretches and pulls on endothelial cells causing pores between to open.
