lOMoAR cPSD| 18092855
Chapter 08: Dysrhythmia Interpretation and
ManagementSole: Introduction to Critical Care Nursing,
8th Edition
,1. Interpret the following rhythm:
a. Normal sinus rhythm
b. Sinus bradycardia
c. Sinus tachycardia
d. Sinus arrhythmia
ANS: A
Normal sinus rhythm (NSR) reflects normal conduction of the sinus impulse through the atria
and ventricles. Atrial and ventricular rates are the same and range from 60 to 100 beats per
minute. Rhythm is regular or essentially regular. PR interval is 0.12 to 0.20 seconds. QRS
interval is 0.06 to 0.10 seconds. P and QRS waves are consistent in shape. Sinus tachycardia
results when the SA node fires faster than 100 beats per minute. Bradycardia is defined as a
heart rate less than 60 beats per minute. Sinus arrhythmia is a cyclical change in heart rate that
is associated with respiration. The heart rate slightly increases during inspiration and slightly
slows during exhalation because of changes in vagal tone.
DIF: Cognitive Level: Analysis
OBJ: Interpret the basic dysrhythmias generated from the sinoatrial node, the atria, the
atrioventricular node, and the ventricles. TOP: Nursing Process Step: Assessment
MSC: NCLEX: Physiological Integrity
,2. Interpret the following rhythm:
a. Normal sinus rhythm
b. Sinus bradycardia
c. Sinus tachycardia
d. Sinus arrhythmia
ANS: C
Normal sinus rhythm (NSR) reflects normal conduction of the sinus impulse
through the atria and ventricles. Atrial and ventricular rates are the same and
range from 60 to 100 beats per minute. Rhythm is regular or essentially
regular. PR interval is 0.12 to 0.20 seconds. QRS interval is 0.06 to 0.10
seconds. P and QRS waves are consistent in shape. Sinus tachycardia results
when the SA node fires faster than 100 beats per minute. Bradycardia is
defined as a heart rate less than 60 beats per minute. Sinus arrhythmia is a
cyclical change in heart rate thatis associated with respiration. The heart rate
slightly increases during inspiration and slightly slows during exhalation
because of changes in vagal tone.
, lOMoAR cPSD| 18092855
Chapter 08: Dysrhythmia Interpretation and Management
Sole: Introduction to Critical Care Nursing, 8th Edition
MULTIPLE CHOICE
3. Why is the sinus node identified as the pacemaker of the heart?
a. It contains the fastest pacemaker cell in the heart.
b. It has the only pacemaker cell in the heart.
c. It contains the only cell that does not affect the cardiac cycle.
d. It is located in the left side of the heart.
ANS: A
The cardiac cycle begins with an impulse that is generated from a small concentrated area of
pacemaker cells high in the right atria called the sinoatrial node (sinus node or SA node). The
SA node has the fastest rate of discharge and thus is the dominant pacemaker of the heart. The
AV node has pacemaker properties and can discharge an impulse if the SA node fails. The
ventricles have pacemaker capabilities if the sinus node or the AV node ceases to generate
impulses.
DIF: Cognitive Level: Comprehension
OBJ: Explain the relationships between electrical and mechanical events in the heart.
TOP: Nursing Process Step: Assessment MSC: NCLEX: Physiological Integrity
4. What is one of the functions of the atrioventricular (AV) node?
a. Pacing the heart if the ventricles fail
b. Slowing the impulse arriving from the SA node
c. Sending the impulse to the SA node
d. Allowing for ventricular filling during systole
ANS: B
The impulse from the SA node quickly reaches the atrioventricular (AV) node located in the
area called the AV junction, between the atria and the ventricles. Here the impulse is slowed
to allow time for ventricular filling during relaxation or ventricular diastole. The AV node has
pacemaker properties and can discharge an impulse if the SA node (not the ventricle) fails.
The electrical impulse is then rapidly conducted through the bundle of His to the ventricles
(not the SA node) via the left and right bundle branches.
DIF: Cognitive Level: Comprehension
OBJ: Explain the relationships between electrical and mechanical events in the heart.
TOP: Nursing Process Step: Assessment MSC: NCLEX: Physiological Integrity
5. What is the normal rate for the SA node when the patient is at rest?
a. 40 to 60 beats per minute
b. 60 to 100 beats per minute
c. 20 to 40 beats per minute
d. More than 100 beats per minute
ANS: B
Chapter 08: Dysrhythmia Interpretation and
ManagementSole: Introduction to Critical Care Nursing,
8th Edition
,1. Interpret the following rhythm:
a. Normal sinus rhythm
b. Sinus bradycardia
c. Sinus tachycardia
d. Sinus arrhythmia
ANS: A
Normal sinus rhythm (NSR) reflects normal conduction of the sinus impulse through the atria
and ventricles. Atrial and ventricular rates are the same and range from 60 to 100 beats per
minute. Rhythm is regular or essentially regular. PR interval is 0.12 to 0.20 seconds. QRS
interval is 0.06 to 0.10 seconds. P and QRS waves are consistent in shape. Sinus tachycardia
results when the SA node fires faster than 100 beats per minute. Bradycardia is defined as a
heart rate less than 60 beats per minute. Sinus arrhythmia is a cyclical change in heart rate that
is associated with respiration. The heart rate slightly increases during inspiration and slightly
slows during exhalation because of changes in vagal tone.
DIF: Cognitive Level: Analysis
OBJ: Interpret the basic dysrhythmias generated from the sinoatrial node, the atria, the
atrioventricular node, and the ventricles. TOP: Nursing Process Step: Assessment
MSC: NCLEX: Physiological Integrity
,2. Interpret the following rhythm:
a. Normal sinus rhythm
b. Sinus bradycardia
c. Sinus tachycardia
d. Sinus arrhythmia
ANS: C
Normal sinus rhythm (NSR) reflects normal conduction of the sinus impulse
through the atria and ventricles. Atrial and ventricular rates are the same and
range from 60 to 100 beats per minute. Rhythm is regular or essentially
regular. PR interval is 0.12 to 0.20 seconds. QRS interval is 0.06 to 0.10
seconds. P and QRS waves are consistent in shape. Sinus tachycardia results
when the SA node fires faster than 100 beats per minute. Bradycardia is
defined as a heart rate less than 60 beats per minute. Sinus arrhythmia is a
cyclical change in heart rate thatis associated with respiration. The heart rate
slightly increases during inspiration and slightly slows during exhalation
because of changes in vagal tone.
, lOMoAR cPSD| 18092855
Chapter 08: Dysrhythmia Interpretation and Management
Sole: Introduction to Critical Care Nursing, 8th Edition
MULTIPLE CHOICE
3. Why is the sinus node identified as the pacemaker of the heart?
a. It contains the fastest pacemaker cell in the heart.
b. It has the only pacemaker cell in the heart.
c. It contains the only cell that does not affect the cardiac cycle.
d. It is located in the left side of the heart.
ANS: A
The cardiac cycle begins with an impulse that is generated from a small concentrated area of
pacemaker cells high in the right atria called the sinoatrial node (sinus node or SA node). The
SA node has the fastest rate of discharge and thus is the dominant pacemaker of the heart. The
AV node has pacemaker properties and can discharge an impulse if the SA node fails. The
ventricles have pacemaker capabilities if the sinus node or the AV node ceases to generate
impulses.
DIF: Cognitive Level: Comprehension
OBJ: Explain the relationships between electrical and mechanical events in the heart.
TOP: Nursing Process Step: Assessment MSC: NCLEX: Physiological Integrity
4. What is one of the functions of the atrioventricular (AV) node?
a. Pacing the heart if the ventricles fail
b. Slowing the impulse arriving from the SA node
c. Sending the impulse to the SA node
d. Allowing for ventricular filling during systole
ANS: B
The impulse from the SA node quickly reaches the atrioventricular (AV) node located in the
area called the AV junction, between the atria and the ventricles. Here the impulse is slowed
to allow time for ventricular filling during relaxation or ventricular diastole. The AV node has
pacemaker properties and can discharge an impulse if the SA node (not the ventricle) fails.
The electrical impulse is then rapidly conducted through the bundle of His to the ventricles
(not the SA node) via the left and right bundle branches.
DIF: Cognitive Level: Comprehension
OBJ: Explain the relationships between electrical and mechanical events in the heart.
TOP: Nursing Process Step: Assessment MSC: NCLEX: Physiological Integrity
5. What is the normal rate for the SA node when the patient is at rest?
a. 40 to 60 beats per minute
b. 60 to 100 beats per minute
c. 20 to 40 beats per minute
d. More than 100 beats per minute
ANS: B
