OT Flashcards
in which vessels would velocity of flow be slowest?
inferior vena cava
Arterial blood pressure control is independent of local flow and cardiac output?
true
blood flow to most tissues or organs is regulated in proportion to
the metabolic demand
which vessel regulate blood flow to an organ?
arterioles
which change would create the greatsest increase in resistance to flow?
halving the radius of the vessel
increasing the velocity of blood flow decreases the viscosity of blood?
true
if the CO is stopped, what will happen to the arterial blood pressure?
fall until it is equal to CVP or CCP
what effect does fibrinogen have on viscosity of blood?
decrease viscosity
A broadband Doppler reading is obtained over the right carotid artery? what is the significance
partial occlusion
angiogenesis can be impaired by?
anti-inflammatory drugs
which is NOT a result of SNS stimulation?
increase in active skeletal muscle blood flow
IS: increase strenght cardiac contraction, closing pressure, mean circulatory filling pressure
in cardiac failure, what happens to CVP?
increase
which situation will venous return stop?
if CVP pressure is equal to mean circulatory filling pressure
as a tissue becomes more active, what is the primary way local blood flow increase?
release of local vasodilators
what receptor mediates the SNS vasoconstrictor response?
alpha
how does circulating ACH cause local dilation of vascular smooth muscle in a tissue bed?
binds to epithithelium causing release of NO
during ejection of blood, comment of baroreceptor activity?
increase
which would be released by a tissue in response to hypoxia and would promote angiognesis?
VEGF, mediated by adenosine
which is true if blood flow to a tissue doubles, but AVO2 difference falls by 1/2?
likely due to shunting
using indicator dilution to determine cardiac output , as the duration of the curve increases, what is happening to cardiac output?
decrease
in the brain, how is excess plasma filtrate returned to vascular system?
arachnoid villi
what is hydraulic filtering?
stretch and recoil of the arterial tree during the cardiac cycle
if one renal artery was stetonic, which would be expected?
development of hypertension, angiotensin II levels elevated
what is the mechanism by which SNS stimulation to the heart cause local vasodilation of coronary vascular smooth muscle?
NPH stimulation of cardiac cells which release adenosine
which area of the vasomotor center is tonically active and provides basal stimulation of the SNS
pressor center
which is NOT a important lymphatic function?
produce RBCs
DOES: immune function, carried absorbed fats to Gi tract, return plasma filtrate to vascular system
in response to rise in extracellular fluid levels, which change would be counterproductive in keeping blood pressure from rising?
decreased ANP release.
in the fetus, what is the function of ductus venosus?
allows blood returning from placenta to bypass liver and flows into inferior vena cava
in the fetus, the blood that shunts through the ductus arteriosis is returning from what?
Head
slow breathing (6breaths/min) has been shown to decrease both systolic and diastolic BP due to?
decrease sympathetic activity
during exercise, which endpoint is decreasing?
total peripheral resistance
which will NOT increase venous return during exercise?
increased CVP
WILL increase: increase activity of venous pump, depth of ventilation, sympathetic stimulation
if your mean circulatory filling pressure is increased, relative to your CVP which is true?
venous return is decreased
if your CO is stopped and a shunt was placed connecting the aorta with the vena cava , the arterial pressure will fall until it equals?
mean circulatory filling pressure
in a healthy young adult, comment about tissue during diastole.
maintained by recoil of arteries
if blood flow to a tissue doubles, and the AVO2 stays constant, comment on increase in flow?
due to shunting
what is responsible for most of the filtration that occurs in systemic capillaries?
capillary hydrostatic pressure
which effect is NOT attributed to slow breathing?
increase in mean arterial blood pressure
cardiac function, as CVP increase what happens to venous return
decrease
