HOAG ECG COMPREHENSIVE EXAM UPDATED QUESTIONS
AND ANSWERS GRADED A+
✔✔s/s of undersensing - ✔✔palpitations
skipped beats
competition may cause V tach
✔✔causes of undersensing - ✔✔sensitivity not enough
edema or fibrosis at lead
insulation breaks
lead fracture or displacement
inadequate cardiac signal
battery depletion
incorrect setting
✔✔interventions for undersensing - ✔✔*always check on pt first
increase sensitivity
check connections
replace battery
lead repositioned
lead replaced
✔✔transcutaneous pacing def - ✔✔choice of pacing in emergent situation. least
invasive. external electrodes send signal through chest wall. temporary solution
✔✔indications for TCP - ✔✔1. validated RNs can initiate TCP for symptomatic
bradycardia and complete heart block
2. TCP is preferred in pts who need pacemaker and may receive thrombolytics, since
vascular access is not required to place electrodes
✔✔the key to increasing effectiveness of TCP is ... because... - ✔✔early initiation
time is crucial, as hypoxia and acidosis increase, the muscle becomes less responsive
✔✔TCP: electrical capture - ✔✔U shaped pacer spike before wide QRS and broad T
wave
✔✔TCP: mechanical capture - ✔✔assess for pulse on right side of body (left may get
muscle contraction)
adequate blood pressure
improved LOC and skin color, temp, and moisture
✔✔complications of TCP - ✔✔1. unrecognized v fib (turn off temporarily to assess
underlying rhythm)
2. skin burns (change patches Q24)
3. failure to mechanically capture (confirm palpable pulse on right side)
, ✔✔ Normal electrical pathway in heart - ✔✔SA node, AV node, bundle of HIS, right and
left bundle branches, purkinje fibers
✔✔AV node pace if SA isn't working - ✔✔40-60
✔✔Purkinje fiber pace if SA and AV aren't working - ✔✔20-40
✔✔valve order through the heart - ✔✔tricuspid, pulmonic, mitral, aortic valve
✔✔P wave is - ✔✔atrial contraction/depolarization
✔✔QRS wave is - ✔✔ventricular contraction/depolarization
✔✔Q wave is - ✔✔first negative deflection after P wave
✔✔R wave is - ✔✔1st positive deflection after P wave
✔✔S wave is - ✔✔first negative deflection after the R wave
✔✔normal QRS interval - ✔✔0.04-0.12 seconds
✔✔T wave is - ✔✔ventricular relaxation or repolarization
✔✔PR interval is - ✔✔beginning of P wave to beginning of QRS
✔✔normal PR interval - ✔✔0.12-0.20 seconds
✔✔ST segment is - ✔✔not measured, but could be bad if it's elevated or depressed
✔✔QT interval is - ✔✔beginning of QRS complex to end of T wave
✔✔normal QT interval - ✔✔0.36-0.44 seconds, but adjusted for heart rate
✔✔small box = - ✔✔0.04 seconds
✔✔large box = - ✔✔0.20 seconds
✔✔6 second tracing method - ✔✔get 6 second tracing, count the R waves and multiply
by 10
✔✔what is 6 second tracing method good for - ✔✔irregular heart beat
AND ANSWERS GRADED A+
✔✔s/s of undersensing - ✔✔palpitations
skipped beats
competition may cause V tach
✔✔causes of undersensing - ✔✔sensitivity not enough
edema or fibrosis at lead
insulation breaks
lead fracture or displacement
inadequate cardiac signal
battery depletion
incorrect setting
✔✔interventions for undersensing - ✔✔*always check on pt first
increase sensitivity
check connections
replace battery
lead repositioned
lead replaced
✔✔transcutaneous pacing def - ✔✔choice of pacing in emergent situation. least
invasive. external electrodes send signal through chest wall. temporary solution
✔✔indications for TCP - ✔✔1. validated RNs can initiate TCP for symptomatic
bradycardia and complete heart block
2. TCP is preferred in pts who need pacemaker and may receive thrombolytics, since
vascular access is not required to place electrodes
✔✔the key to increasing effectiveness of TCP is ... because... - ✔✔early initiation
time is crucial, as hypoxia and acidosis increase, the muscle becomes less responsive
✔✔TCP: electrical capture - ✔✔U shaped pacer spike before wide QRS and broad T
wave
✔✔TCP: mechanical capture - ✔✔assess for pulse on right side of body (left may get
muscle contraction)
adequate blood pressure
improved LOC and skin color, temp, and moisture
✔✔complications of TCP - ✔✔1. unrecognized v fib (turn off temporarily to assess
underlying rhythm)
2. skin burns (change patches Q24)
3. failure to mechanically capture (confirm palpable pulse on right side)
, ✔✔ Normal electrical pathway in heart - ✔✔SA node, AV node, bundle of HIS, right and
left bundle branches, purkinje fibers
✔✔AV node pace if SA isn't working - ✔✔40-60
✔✔Purkinje fiber pace if SA and AV aren't working - ✔✔20-40
✔✔valve order through the heart - ✔✔tricuspid, pulmonic, mitral, aortic valve
✔✔P wave is - ✔✔atrial contraction/depolarization
✔✔QRS wave is - ✔✔ventricular contraction/depolarization
✔✔Q wave is - ✔✔first negative deflection after P wave
✔✔R wave is - ✔✔1st positive deflection after P wave
✔✔S wave is - ✔✔first negative deflection after the R wave
✔✔normal QRS interval - ✔✔0.04-0.12 seconds
✔✔T wave is - ✔✔ventricular relaxation or repolarization
✔✔PR interval is - ✔✔beginning of P wave to beginning of QRS
✔✔normal PR interval - ✔✔0.12-0.20 seconds
✔✔ST segment is - ✔✔not measured, but could be bad if it's elevated or depressed
✔✔QT interval is - ✔✔beginning of QRS complex to end of T wave
✔✔normal QT interval - ✔✔0.36-0.44 seconds, but adjusted for heart rate
✔✔small box = - ✔✔0.04 seconds
✔✔large box = - ✔✔0.20 seconds
✔✔6 second tracing method - ✔✔get 6 second tracing, count the R waves and multiply
by 10
✔✔what is 6 second tracing method good for - ✔✔irregular heart beat
