test 1 electric/hemo notes Flashcards
electronics and interventional
how many Hz is 60 BPM
1 Hz
how many Hz is 120 BPM
2 Hz
what has a lower frequency; saline or contrast
contrast (because it’s thicker, that’s why it causes flatline when injected)
what decreases as harmonic increases
amplitude
hemodynamic requires how much harmonics
10
the equation used for finding optimally damped
BPM/60 secs=fundamental frequency*10th harmonic
when is wedge pressure taken
end of expiratory (10-15mmhg) when balloon is inflated
how does string gauge work in wheatstone bridge
diaphragm hits wires
what causes transducer to be mistakenly high or low when placed above or below the midchest line
gravity
3 things that cause greater damping
greater fluid viscosity (contrast rather than saline)
smaller catheter size (5F rather than 6F)
less dense fluid (injecting bubbles)
how to fix damping caused by greater fluid viscosity
flush contrast
how to fix damping caused by catheter
move catheter to be more coaxial
what type of damp is also known as critically damp
optimal damp
what type of damp causes greater artificial pressure
under damp
what type damp is less responsive to rapid alterations in pressure
over damp
which symbol holds/store charge
capacitor
which symbol stores positive negative
battery/ DC storage device
which symbol zero voltage and absorbs charge
ground
which symbol bridge for DC
diode
which symbol creates peaks and valleys
resistors
which symbol boosts current
coil
which symbol has sine wave
ac voltage source
high resistance in wheastone gives us while low gives us
systole;diastole
you don’t get anything if
all resistors are equal no high or low
how to find pressure for edp, in graph etc
graph scale divide by 50 muiltply by amount of boxes
carrier signal into strain gauge out into scrambled and then descrambled in output (display) is
modulation and demodulation
drop in systolic pressure is characterized by
ventricularization
