Vascular Physiology Flashcards
blood
-mostly made of water
-if you were to put blood in a test tube and let it sit, you would see the blood cells fall to the bottom that are called the hematocrit
-above it is the water which makes up a large % of the plasma as well as proteins like albumin, globulin, and fibrinogen
-RBC, WBC, and platelets
hemodynamics
-pressure = flow x resistance or delta P = Q x R where Q is the heart when it squeezes (cardiac output), R is the vessels constricting or dilating, and P is the blood pressure
cardiac ouput
stroke volume x heart rate and it defines the heart squeezing or relaxing
anatomy of the cardiovascular system
comprised of the heart, pulmonary circulation, and systemic circulation
pulmonary circulation
-heart pumps blood —> lungs —> comes back oxygenated
-heart pumps red blood —> body —> comes back deoxygenated
-blood flow, gas exchange, and one of the carriers of gas exchange is the hepatic vein
what is gas exchange and where does gas exchange occur?
occurs across capillaries and it is when blue blood loses CO2 and gains O2 in the lungs
gas exchange
-oxygen enters the lung into grape-like structures called alveolus
-oxygen diffuses across the alveoli and goes into the blood
oxygen and hemoglobin
oxygen gets dissolved in water at low level but combines with hemoglobin at higher level —> RBCs diffuse
systemic circulation
-blood flow of oxygenated blood
-LV pumps oxygenated blood to the tissues of the body
-O2 is unloaded by the RBCs
oxygen transport
oxygen in air —> lungs —> blood —> peripheral tissues
vascular histology
blood vessels all have the same 3 layers but depending on where you are in body, some may have more of one layer compared to another
3 layers of vessels
- adventitia
- media
- intima
intima
endothelial cells with internal elastic lamina
media
-in the middle of the vessel walls
-smooth muscle cells with external elastic lamina
adventitia
-outside of the vessel
-composed of smooth muscle cells and connective tissue
Ex. strong, powerful arteries have a lot of smooth muscles where the media is big but weak veins have only a little bit of smooth muscle
different types of vessels
arteries, capillaries, and veins
arteries
-deliver blood to the periphery
-on a graph showing the bp vs the different types of vessels, you see the biggest drop in BP across the arterioles
-arteries, particulary arterioles, regulate blood flow into the capillaries
arterioles
very small blood vessels that branch off of arteries and carry blood from heart to peripheral tissues
capillaries
-thin-walled vessels with pores
-diffusion and gas exchange occurs across them
-red blood from heart and blue blood to heart with the connection being the capillaries
-BP is continuing to drop as you go from left to right
what happens as you go from left to right in capillaries?
-from left, you have the fluid being pushed out like water and the ions go with it
-as the blood gets closer to the venuoles the fluid and waste products come in
what two principles does fluid move across the capillaries?
hydrostatic pressure and oncotic pressure
hydrostatic pressure
pressure pushing the fluid out
oncotic pressure
when water gets drawn out against the concentration gradient, a lot of the proteins are left in the capillary with less water so this pressure causes the water to get sucked back in
what type of movement of fluid do you have at the start of the capillary and at the end?
net movement