IBHRE Prep Exam
Voltage is? - ANS-The electromotive force pushing on electrons
If the PM output voltage is 5v and the measured lead resistance is 330 ohms, then the
current that flows out of the pacemaker into the heart is? - ANS-15.15
I=V/R=5V/.33 k ohm
If a unipolar lead wire has an insulation break one would expect the resistance to? -
ANS-decrease
for a wire fracture the resistance? - ANS-increases
if the output vlotage of the pacemaker is programmed from 5 volts to 2.5 volts, the
energy delivered to the heart is? - ANS-quartered
Which of the following affect the longevity of the PM? - ANS-output voltage, resistance
of lead and amount % pacing
Which Pt's PM will last longer? - ANS-#1: AMP=5V, L.R.=90, resistance 500ohms,
PW=.5ms, 100%pacing
#2: AMP=5V, L.R.=60, resistance 500ohms, PW=.5ms, 100%pacing
#3: AMP=2.5V, L.R.=60, resistance 330ohms, PW=.5ms, 100% pacing
(#4: AMP=2.5v, L.R.=60, resistance 500ohms, PW=.5ms, 50%pacing)
The strength duration curve is dependent on the? - ANS-Cell's membrane capacitance,
intracellular and extracellular resistance and threshold voltage.
A patient on flecainide should? - ANS-Have their threshold checked
The acute threshold peaking is due to? - ANS-Trauma and inflammation
An advantage of bipolar leads is? - ANS-They are less susceptible to EMI
The two parameters that are important for ventricular sensing and should be measured
are? - ANS-R-wave amplitude and slew rate
Voltage is? - ANS-The electromotive force pushing on electrons
If the PM output voltage is 5v and the measured lead resistance is 330 ohms, then the
current that flows out of the pacemaker into the heart is? - ANS-15.15
I=V/R=5V/.33 k ohm
If a unipolar lead wire has an insulation break one would expect the resistance to? -
ANS-decrease
for a wire fracture the resistance? - ANS-increases
if the output vlotage of the pacemaker is programmed from 5 volts to 2.5 volts, the
energy delivered to the heart is? - ANS-quartered
Which of the following affect the longevity of the PM? - ANS-output voltage, resistance
of lead and amount % pacing
Which Pt's PM will last longer? - ANS-#1: AMP=5V, L.R.=90, resistance 500ohms,
PW=.5ms, 100%pacing
#2: AMP=5V, L.R.=60, resistance 500ohms, PW=.5ms, 100%pacing
#3: AMP=2.5V, L.R.=60, resistance 330ohms, PW=.5ms, 100% pacing
(#4: AMP=2.5v, L.R.=60, resistance 500ohms, PW=.5ms, 50%pacing)
The strength duration curve is dependent on the? - ANS-Cell's membrane capacitance,
intracellular and extracellular resistance and threshold voltage.
A patient on flecainide should? - ANS-Have their threshold checked
The acute threshold peaking is due to? - ANS-Trauma and inflammation
An advantage of bipolar leads is? - ANS-They are less susceptible to EMI
The two parameters that are important for ventricular sensing and should be measured
are? - ANS-R-wave amplitude and slew rate
