NURS 2055: Dysrhythmias Exam Questions
With Correct Answers 100% Verified.
What is a dysrhythmia? - Answer✔any abnormal cardiac rhythms
What is the path of a normal electrical impulse in the heart? - Answer✔-cardiac impulse begins
in the SA node in the right upper atrium
-transmitter over the atrial myocardium via the bundle of Bachmann and the internodal
pathways which causes atrial contraction
-the impulse then travels to the AV node through the bundle of His and down the left and right
bundle branches, ending in the Purkinje fibres which transmits the impulse to the ventricles
Depolarization corresponds with ______ - Answer✔contraction of myocardial muscle
Repolarization corresponds with ______- - Answer✔relaxation of myocardial muscle
What does the P wave represent? - Answer✔depolarization of the atria
What does the PR segment represent? - Answer✔the time taken for the impulse to spread
through the atria
What does the QRS complex represent? - Answer✔depolarization of the ventricles
What does the ST segment represent? - Answer✔end of depolarization and beginning of
repolarization of the ventricles
What does the T wave represent? - Answer✔repolarization of the ventricles
If present, what does the U wave represent? - Answer✔repolarization of the Purkinje fibres
The PR, QRS, and QT intervals reflect ________ - Answer✔the length of time it takes for the
impulse to travel from one area of the heart to another.
What does automaticity mean? - Answer✔Ability to initiate an impulse spontaneously and
continuously
What does contractility mean? - Answer✔Ability to respond mechanically to an impulse
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What does conductivity mean? - Answer✔Ability to transmit an impulse along a membrane in
an orderly manner
What does excitability mean? - Answer✔Ability to be electrically stimulated
What is the normal duration of the P wave? - Answer✔0.06-0.12 seconds
What is the normal duration of the PR interval? - Answer✔0.12-0.2 seconds
What is the normal duration of the QRS interval? - Answer✔0.06-0.1 seconds
The autonomic nervous system played an important role in ______ - Answer✔the rate of
impulse formation, the speed of conduction, and the strength of cardiac contraction
What does ECG stand for? - Answer✔electrocardiogram monitoring
What is an ECG? - Answer✔Graphic tracing of electrical impulses produced by the heart
Waveforms of ECG represent ______ - Answer✔Waveforms of ECG represent activity of
charged ions across membranes of myocardial cells. (depolarization and repolarization)
Potassium is ___ in the cell whereas sodium is ____ in the cell - Answer✔high low
When the cell is at rest, or in a repolarized state, it is _____. - Answer✔negative compared to
the outside
During depolarization the cell is ____ compared to the outside of the cell. - Answer✔Positive
Each small square on an ECG represents ______ - Answer✔0.04 seconds and 0.1mV
Each large square on an ECG represents _____ - Answer✔0.2 seconds
0.5mV
When we calculate heart rate form an ECG strip we are counting ____ - Answer✔the number of
QRS complexes in 1 minute
What are the 3 ways we can calculate HR? - Answer✔1. # of R-R intervals= ___ x10= __ bpm
2. Large squares between R-R interval= 300/__ = __bpm
3. Small squares between R-R interval= 1500/__ = ___bpm
What is an artifact? - Answer✔defined as electrocardiographic alterations, not related to
cardiac electrical activity (ie. too much hair on a patients chest)
What are some examples of things that can cause dysrhythmias? - Answer✔-acid base
imbalances
-alcohol
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