EXAM BASIC DYSRHYTHMIAS FULLY SOLVED #8
What do you do if artifacts occur on an ECG? - correct answer check connections in
equipment
Rhythm starts in the SA node, 60-100 BPM, normal conduction pathway - correct
answer normal sinus rhythm
Normal P wave length - correct answer .06-.20
The time of passive of impulse through the atria, causing atrial depolarization (atrial
contraction) - correct answer P wave
Normal PR interval length - correct answer .12-.20
Time taken for the impulse the spread through the atria, AV node, and bundle of HIS,
bundle branches, & purkinje fibers, right up until ventricular contraction.
(atrial contraction -> beginning of ventricular contraction) - correct answer PR interval
Normal QRS length - correct answer <.12
Time taken for depolarization of both ventricles
(systole- ventricular contraction) - correct answer QRS
Normal ST segment length - correct answer .12
Time between ventricular depolarization and repolarization; should be isoelectric.
(end of systole -> beginning of diastole) - correct answer ST segment
Normal T wave length - correct answer .16
Ventricular relaxation (diastole) - correct answer T wave
Is K or Na higher inside the cell? - correct answer K
Is K or Na higher outside the cell? - correct answer Na
What happens with depolarization of a cell? - correct answer Na influx into cell
Normal QT - correct answer .34-.43
Time taken for entire depolarization/repolarization of ventricles
(ventricular contraction + relaxation)
(ventricular diastole + systole) - correct answer QT
, The ability of a cardiac cell to fire spontaneously without being activated - correct
answer automaticity
The ability of a cell to become depolarized; determined by the length of time after
depolarization that they can be restimulated (the refractory periods) - correct answer
excitability
SA node is firing <60 BPM
P, QRS, T all normal
Regular rhythm - correct answer sinus bradycardia
Is sinus bradycardia ever normal? - correct answer yes- it's only significant when
symptomatic
Symptoms of sinus bradycardia - correct answer syncope, chest pain, pale/cool skin,
hypotension, weakness, angina, dizziness, confusion, SOB
SA node firing >100 BPM
Regular rhythm
Normal P and QRS
QT <0.35 (shortened) - correct answer sinus tachycardia
The nurse knows that exercise, fever, pain, hypotension, hypovolemia, anemia,
hypoxia, hypoglycemia, myocardial ischemia, HF, hyperthyroid, and anxiety can all
cause - correct answer sinus tachycardia
Why may sinus tachycardia cause angina? - correct answer inc O2 consumption in the
heart
Sinus tachy Tx - correct answer vagal stimulation, beta blocker, adenosine, CCB
Sinus brady Tx - correct answer atropine (anticholinergic) (if that doesn't work-
dopamine, epi)
Atrial tachydysrhymia
Recurring, regular, COARSE, SAWTOOTH-SHAPED waves
Caused by one single point in the R atrium
Regular rhythm
PR interval unmeasurable
QRS normal
May see some AV block - correct answer atrial flutter
What is the risk with an atrial dysrhythmia? - correct answer loss of atrial kick, so drop in
CO (can cause HF); risk for clot formation (stroke/PE because of blood stasis)