test 1 electric/hemo hw Flashcards
electronics and interventional
when catheter is too deep seated and receives backward pressure from the myocardium
ventricularization of the coronary artery
20 mmhg cardiac pressure recording too low. where was the transducer zeroed?
10 in above pt mid chest. (+2mmHg for every inch above level)
the usual sweep speed for displaying pressure recordings is
10 sec
another name for string gauge is
wheatstone bridge
adding extra lengths of tubing will cause
drop in pressure
balancing is also known as
zero
AO-RV-PA is this pullback or insertion?
insertion
PA-RV-AO is this pullback or insertion
pullback
high frequency filter can cause damping
false
arterial have triangular which have sine waves
none
time shifting the pcw waveform is useful to ensure accuracy when measuring
mitral valve gradient
a. No overshoot
b. No over damping
c. Good signal to noise ratio
d. Appropriate filtering
these are known as
optimal frequency response
a. Inappropriate frequency response caused by damping coefficient
b. Tangled cables, loose connections
c. Fluid leaks
d. Electromagnetic interference
these are considered
electronic artifacts
Pressure applied to a liquid at any point is transmitted equally in all
directions is known as
pascals law
pascals and mmhg are units of
pressure
the filters used in hemodynamic monitoring is ______ band pass filter
low
which waveform would be the most likely for respiration excursion
PCW
proper filtering gets rid of respiratory variation
false
a _____hz filter gets rid of ac power interference
60
strain gauge converts fluid pressure to an electrical signal using
variable resistors
two pressure channels are required to record
simultaneous pressures
what assures proper baseline and top of scale channels
calibration
changing the ____adjusts band pass filter to reduce noise
HZ
40 mm scale is for
Right heart pressures
wheatstone bridge is located
transducer
electrucak signal is converted into a waveform by process called
modulation-demodulation
transducer that is zeroed while lying below level of pt mid chest will result in
mistakenly high pressures
mid axillary is also mid chest is also
phlebostatic axis
for radial arterial line on sitting up pt, where should zero port be positioned
at level of radial artery catheter
temp drift of a pressure transducer should be corrected periodically by
opening to air and pressing zero button
hr 60-100 what should frequency be
14 hz
what is used for testing optimal damping
square wave test
Ao pressure in hypotensive pt or pa pressure in pt with pulmonary htn what scale would you use
100mmHG
tracing is wonky too much going on what to use for improve pressure waveform
apply band pass filter to eliminate high frequencies
wheatstone bridge is a
direct current bridge
range of wheatstone bridge in ohms
1ohm to several Mohms
wheatstone bridge is used to calculate
mmhg pressure
wheatstone bridge displays
waveforms
wheatstone bridge is used for the measurement of physical parameters
as a strain gauge
by using variations on a wheatstone bridge we can measure
resistance and impedance
simplest applications of wheatstone bridge is
transducer
thermal compensation can be provided in a wheatstone bridge
re-zeroing to atmosphere periodically
pressure transducers come precalibrated at 0mmhg
false
pressure transducers sensitivity come precalibrated from the factory at 100 mmhg
true
radial artery systolic pressure is usually higher than Ao systolic pressure
true
the square wave flush test evaluates the fluid filled transducer system for proper damping
true
on the chest the junction of the manubrium and the sternum is known as
angle of Louis
squeezing inverted IV pressure bag because
eject air
when zeroing pressure transducer the air zero stopcock should be adjusted to the phlebostatic axis which is considered to be
Ra
when pt left arm is raised the zero level
should remain at Chets level
when pulling tail is squeezing the white continous flow device it
flushes the transducer
arterial line pressure should be inflated to
300 mmhg
what level the pressure transducer to the pt mid axillary line
bubble float level
frequency is measured in
hz
current is measured in
amps
resistance is measured in
ohms
electronic force is measured in
volts
radiation exposure is measured in
sieverts
another name for pressure recording amplifier
carrier amplifier
when Cath in left coronary pressure drops the catheter should be
pulls back
left coronary ostia is cannulated this drop in diastolic pressure is
ventricularization
elimination of vibrations at a certain frequency is accomplished thorigh the use of
filters
