Vascular Disorders Flashcards
cardiac output =
beats per minute * stroke volume
stroke volume =
volume of blood per beat by ventricle
which side of the circulatory system pumps to the lungs
right side
which side of the circulatory system pumps systemically
left
what is responsible for the exchange of nutrients and waste products
systemic microvasculature
true or false:
arteries have large diameter lumens
true
which vessel allows rapid blood flow with minimal resistance and a thick tunica media
arteries
which vessels are responsible for distributing blood to the greatest areas of need
arterioles
true or false:
arterioles are major vascular resistance vessels
true
what controls the lumen of the arterioles
smooth muscle + elastic fiber
sympathetic innervation
what vessel has thin walls and inter-endothelial pores to support nutrient/waste product exchange between blood and tissues
capillaries
which tissues in the body have continuous capillaries
brain (blood-brain barrier)
muscle
lung
bone
which tissues have fenestrated capillaries
renal glomeruli
intestines
endocrine
choroid plexuses
what is able to pass through fenestrated capillaries
small solutes only
which capillaries are ideal to pass leukocytes, RBCs, platelets and large proteins
discontinuous (sinusoidal)
which tissues would you expect to see discontinuous capillaries
liver
spleen
bone marrow
lymph nodes
what is the first vessel in the systemic circulation return blood to the heart
venules
which vessels have low vascular resistance, low pressure and has valves to prevent backflow
venules/ veins
how is the blood able to move back towards the heart in the vein
valves
negative pressure in the lung
decreased pressure in the heart during filling
what are blind-ended capillaries parallel to vascular capillaries
lymphatic vessels
what are the characteristics of the lymphatic system vessels
large inter-endothelial gaps
valves to prevent back flow
low pressure vessels w/ smooth muscle to allow fluid to enter back into blood
in right sided heart failure, which vessels have increased pressure and where does blood pool?
systemic circulation – portal veins
liver = ascites in abdomen
in left sided heart failure, which vessels have increased pressure and where will blood pool
pulmonary vessels
lungs - pleural edema & pulmonary edema
what is the pressure in a fluid system acted on by a pump
hydraulic pressure
what pressure is the force applied to arterial walls
systolic blood pressure
what does systolic blood pressure favor
filtration
which pressure creates an osmotic pressure
colloidal osmotic pressure
what does colloidal osmotic pressure favor
retention of fluid
what is the main contributor to oncotic pressure
albumin
which end of the systemic capillaries will have a positive net filtration
arteriolar end
why does the arteriolar end have a positive net filtration
positive net filtration = filtration out of the vessel
which end of the systemic capillaries has a negative net reabsorption
venule end
why is it important to keep a negative net reabsorption in the venule end
encourages resorption of fluid and proteins
what does the oncotic pressure gradient depend on
intravascular v extravascular protein concentrations
where does most fluid return to in the body
low pressure venules
what removes the excess interstitial fluid in cases threatening edema
lymphatics
what can occur if there is disfunction of the lymphatic system
edema in periphery and tissues because there is nothing ‘sucking’ the water back up
true or false:
the arteriolar end has a net driving pressure outward causing filtration due to high hydraulic pressure
true
true or false:
venous end has a net driving pressure inward due to low P cap encouraging resorption
true
what pressure is responsible for keeping fluids in vessels due to albumin
oncotic pressure
what ‘defects’ would cause fluid leakage from the blood into the interstitium causing edema
increased hydraulic pressure
decreased oncotic pressure
what can act as a fluid buffer compartment to increase or decrease plasma volume to ensure effective circulatory function
interstitial ECF
if there is an increased plasma volume with water moving into the interstitium, what can occur
cell swelling (hypervolemia)
if there is decreased plasma volume and water leaves the interstitium, what can occur
cells shrink (hypovolemia)
what are the 4 major alternations in capillary dynamics that cause edematous states
intravascular permeability
increased hydraulic pressure
decreased oncotic pressure
decreased lymphatic drainage
what are some causes of increased intravascular permeability
inflammatory vasoactive substances
infectious agents
immune mediated mechanisms
toxins
clotting abnormalities
what can form/occur due to increased intravascular permeability
exudates - leakage of proteins and movement of inflammatory cells into spaces
what are some caused of increased hydraulic pressure
heart failure
localized venous obstruction
fluid overload
what can cause imbalance between intravascular and interstitial compartments in cardiac failure leading to edema
alteration in capillary dynamics
1. decreased cardiac output leads to fluid moves to interstitium
2. decreased plasma fluid volume triggers retention of sodium and water by kidney – augments edema
what is the main cause of decreased intravascular osmotic pressure
decreased albumin production due to liver failure or malnutrition
what are some causes of decreased lymphatic drainage of excess interstitial fluid
neoplasia
lymphangitis
what stains pink on a slide due to protein concentration
edema
how are effusions termed
by location
where would you expect to see hydropericardium
pericardial effusion
what is a pleural effusion
hydrothorax
what is ascites or hydroperitoneum
peritoneal effusion
