hemodynamic measurements Flashcards
velocity equals
flow/ area
vessel RESISTANCE is ____ proportional to radius to the 4th power
indirectly
FLOW is ___ proportional to radius to 4th
directyl
(bernoulli) stenosis - velocity ___ as diameter decreases
increases
normal SVR
700-1600
SVR is primarily determined by
changes in blood vessel diameters
when the volume of flow starts to decrease, arterial resistance ___. because the organ is saying I need ____!
decreases , dilates. volume… (doesnt constrict thinking its a BP problem)
CO =
hr x SV
CO is ____ related to area under the curve
inversely
so poor CO has ___ area under the curve
big
dicrotic notch represents
aortic valve closing
excessive dampening
underestimated systolic and overestimated diastolic
underdampening
overestimated systolic and underestimated distolic
CVP: a wave
RA contraction
C wave
elevation of cusp of tricuspid
V wave
back pressure wave from blood filling RA
In a healthy individual with disease-free arteries, does systolic blood pressure increase or decrease in the leg relative to the proximal aorta
The systolic pressure rises and the diastolic pressure falls, therefore the pulse pressure increases, as the pressure pulse travels away from the aorta. Map should stay the same.
What is damping in an arterial line tracing?
How quickly those vibrations - the harmonic oscillator, “bouncing” a couple of times before coming to rest
what is ringing in A-line
exaggerated systolic component of an arterialwaveform. affects MAP
once you see the dicrotic notch you are back in the
artery
Patients with a left to right shunt can display this type of CO measurement:
high
One of the most common problems with obtaining accurate cardiac output measurements is:
improper injectate administration
wedge wave looks like
caterpillar
when youre in the RA looks like
CVP
when youre in the PA looks like
cvp
when youre in RV looks like
staircase
normal PVR
150-250
RA
0-5
RV
25/5
PA
25/10
LA
8-10
LV
120/10
Aortic pressure
120/80
