35: Dysrhythmias Exam With
Complete Answers.
1. To determine whether there is a delay in impulse conduction through the atria, the nurse will measure the
j j j j j j j j j j j j j j j j j j
duration of the patient's
j j j j
a. P wave.
j j
b. Q wave.
j j
c. P-R interval.
j j
d. QRS complex. - CORRECT ANSWER✔✔A
j j j j j
The P wave represents the depolarization of the atria. The P-R interval represents depolarization of the
j j j j j j j j j j j j j j j
atria, atrioventricular (AV) node, bundle of His, bundle branches, and the Purkinje fibers. The QRS
j j j j j j j j j j j j j j j
represents ventricular depolarization. The Q wave is the first negative deflection following the P wave and
j j j j j j j j j j j j j j j j
should be narrow and short.
j j j j j
DIF: Cognitive Level: Understand (comprehension) REF: 791
j j j j j j
TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
, 2. The nurse needs to quickly estimate the heart rate for a patient with a regular heart rhythm. Which
j j j j j j j j j j j j j j j j j j j
j method will be best to use? j j j j j
a. Count the number of large squares in the R-R interval and divide by 300.
j j j j j j j j j j j j j j
b. Print a 1-minute electrocardiogram (ECG) strip and count the number of QRS complexes.
j j j j j j j j j j j j j
c. Calculate the number of small squares between one QRS complex and the next and divide into 1500.
j j j j j j j j j j j j j j j j j
d. Use the 3-second markers to count the number of QRS complexes in 6 seconds and multiply by 10. -
j j j j j j j j j j j j j j j j j j j
CORRECT ANSWER✔✔D
j j
This is the quickest way to determine the ventricular rate for a patient with a regular rhythm. All the other
j j j j j j j j j j j j j j j j j j j
methods are accurate, but take longer.
j j j j j j
DIF: Cognitive Level: Apply (application) REF: 789-790
j j j j j j
TOP: Nursing Process: Assessment MSC: j j j j
Physiological Integrity j
3. A patient has a junctional escape rhythm on the monitor. The nurse will expect the patient to have a heart
j j j j j j j j j j j j j j j j j j j j j
j rate of _____ beats/minute. j j j
a. 15 to 20 j j j j
b. 20 to 40 j j j j
c. 40 to 60 j j j
d. 60 to 100 - CORRECT ANSWER✔✔C
j j j j j j
If the sinoatrial (SA) node fails to discharge, the atrioventricular (AV) node will automatically discharge at
j j j j j j j j j j j j j j j
the normal rate of 40 to 60 beats/minute. The slower rates are typical of the bundle of His and the Purkinje
j j j j j j j j j j j j j j j j j j j j j
system and may be seen with failure of both the SA and AV node to discharge. The normal SA node rate is 60
j j j j j j j j j j j j j j j j j j j j j j j
to 100 beats/minute.
j j j
DIF: Cognitive Level: Understand (comprehension) REF: 797
j j j j j j
,TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
4. The nurse obtains a rhythm strip on a patient who has had a myocardial infarction and makes the
j j j j j j j j j j j j j j j j j j j
j following analysis: no visible P waves, P-R interval not measurable, ventricular rate 162, R-R interval regular,
j j j j j j j j j j j j j j j
j and QRS complex wide and distorted, QRS duration 0.18 second. The nurse interprets the patient's cardiac
j j j j j j j j j j j j j j j
j rhythm as j
a. atrial flutter.
j j
b. sinus tachycardia.
j j
c. ventricular fibrillation.
j j
d. ventricular tachycardia. - CORRECT ANSWER✔✔D
j j j j j
The absence of P waves, wide QRS, rate >150 beats/minute, and the regularity of the rhythm indicate
j j j j j j j j j j j j j j j j
ventricular tachycardia. Atrial flutter is usually regular, has a narrow QRS configuration, and has flutter
j j j j j j j j j j j j j j j
waves present representing atrial activity. Sinus tachycardia has P waves. Ventricular fibrillation is irregular
j j j j j j j j j j j j j j
and does not have a consistent QRS duration.
j j j j j j j j
DIF: Cognitive Level: Apply (application) REF: 794
j j j j j j
TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
5. The nurse notes that a patient's cardiac monitor shows that every other beat is earlier than expected, has
j j j j j j j j j j j j j j j j j j j
j no visible P wave, and has a QRS complex that is wide and bizarre in shape. How will the nurse document the
j j j j j j j j j j j j j j j j j j j j j
j rhythm?
a. Ventricular couplets
j j
b. Ventricular bigeminy
j j
c. Ventricular R-on-T phenomenon
j j j
d. Multifocal premature ventricular contractions - CORRECT ANSWER✔✔B
j j j j j j j
, Ventricular bigeminy describes a rhythm in which every other QRS complex is wide and bizarre looking. Pairs
j j j j j j j j j j j j j j j j
of wide QRS complexes are described as ventricular couplets. There is no indication that the premature
j j j j j j j j j j j j j j j j
ventricular contractions (PVCs) are multifocal or that the R-on-T phenomenon is occurring.
j j j j j j j j j j j j
DIF: Cognitive Level: Apply (application) REF: 799
j j j j j j
TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
6. A patient has a normal cardiac rhythm and a heart rate of 72 beats/minute. The nurse determines that the
j j j j j j j j j j j j j j j j j j j j
j P-R interval is 0.24 seconds. The most appropriate intervention by the nurse would be to
j j j j j j j j j j j j j j
a. notify the health care provider immediately.
j j j j j j
b. give atropine per agency dysrhythmia protocol.
j j j j j j
c. prepare the patient for temporary pacemaker insertion.
j j j j j j j
d. document the finding and continue to monitor the patient. - CORRECT ANSWER✔✔D
j j j j j j j j j j j j
First-degree atrioventricular (AV) block is asymptomatic and requires ongoing monitoring because it may
j j j j j j j j j j j j
progress to more serious forms of heart block. The rate is normal, so there is no indication that atropine is
j j j j j j j j j j j j j j j j j j j j
needed. Immediate notification of the health care provider about an asymptomatic rhythm is not
j j j j j j j j j j j j j j
necessary.
j
DIF: Cognitive Level: Apply (application) REF: 798
j j j j j j
TOP: Nursing Process: Implementation MSC:
j j j j
Physiological Integrity j
7. A patient who was admitted with a myocardial infarction experiences a 45-second episode of ventricular
j j j j j j j j j j j j j j j j
j tachycardia, then converts to sinus rhythm with a heart rate of 98 beats/minute. Which of the following
j j j j j j j j j j j j j j j j
j actions should the nurse take next?
j j j j j
a. Immediately notify the health care provider.
j j j j j j
Complete Answers.
1. To determine whether there is a delay in impulse conduction through the atria, the nurse will measure the
j j j j j j j j j j j j j j j j j j
duration of the patient's
j j j j
a. P wave.
j j
b. Q wave.
j j
c. P-R interval.
j j
d. QRS complex. - CORRECT ANSWER✔✔A
j j j j j
The P wave represents the depolarization of the atria. The P-R interval represents depolarization of the
j j j j j j j j j j j j j j j
atria, atrioventricular (AV) node, bundle of His, bundle branches, and the Purkinje fibers. The QRS
j j j j j j j j j j j j j j j
represents ventricular depolarization. The Q wave is the first negative deflection following the P wave and
j j j j j j j j j j j j j j j j
should be narrow and short.
j j j j j
DIF: Cognitive Level: Understand (comprehension) REF: 791
j j j j j j
TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
, 2. The nurse needs to quickly estimate the heart rate for a patient with a regular heart rhythm. Which
j j j j j j j j j j j j j j j j j j j
j method will be best to use? j j j j j
a. Count the number of large squares in the R-R interval and divide by 300.
j j j j j j j j j j j j j j
b. Print a 1-minute electrocardiogram (ECG) strip and count the number of QRS complexes.
j j j j j j j j j j j j j
c. Calculate the number of small squares between one QRS complex and the next and divide into 1500.
j j j j j j j j j j j j j j j j j
d. Use the 3-second markers to count the number of QRS complexes in 6 seconds and multiply by 10. -
j j j j j j j j j j j j j j j j j j j
CORRECT ANSWER✔✔D
j j
This is the quickest way to determine the ventricular rate for a patient with a regular rhythm. All the other
j j j j j j j j j j j j j j j j j j j
methods are accurate, but take longer.
j j j j j j
DIF: Cognitive Level: Apply (application) REF: 789-790
j j j j j j
TOP: Nursing Process: Assessment MSC: j j j j
Physiological Integrity j
3. A patient has a junctional escape rhythm on the monitor. The nurse will expect the patient to have a heart
j j j j j j j j j j j j j j j j j j j j j
j rate of _____ beats/minute. j j j
a. 15 to 20 j j j j
b. 20 to 40 j j j j
c. 40 to 60 j j j
d. 60 to 100 - CORRECT ANSWER✔✔C
j j j j j j
If the sinoatrial (SA) node fails to discharge, the atrioventricular (AV) node will automatically discharge at
j j j j j j j j j j j j j j j
the normal rate of 40 to 60 beats/minute. The slower rates are typical of the bundle of His and the Purkinje
j j j j j j j j j j j j j j j j j j j j j
system and may be seen with failure of both the SA and AV node to discharge. The normal SA node rate is 60
j j j j j j j j j j j j j j j j j j j j j j j
to 100 beats/minute.
j j j
DIF: Cognitive Level: Understand (comprehension) REF: 797
j j j j j j
,TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
4. The nurse obtains a rhythm strip on a patient who has had a myocardial infarction and makes the
j j j j j j j j j j j j j j j j j j j
j following analysis: no visible P waves, P-R interval not measurable, ventricular rate 162, R-R interval regular,
j j j j j j j j j j j j j j j
j and QRS complex wide and distorted, QRS duration 0.18 second. The nurse interprets the patient's cardiac
j j j j j j j j j j j j j j j
j rhythm as j
a. atrial flutter.
j j
b. sinus tachycardia.
j j
c. ventricular fibrillation.
j j
d. ventricular tachycardia. - CORRECT ANSWER✔✔D
j j j j j
The absence of P waves, wide QRS, rate >150 beats/minute, and the regularity of the rhythm indicate
j j j j j j j j j j j j j j j j
ventricular tachycardia. Atrial flutter is usually regular, has a narrow QRS configuration, and has flutter
j j j j j j j j j j j j j j j
waves present representing atrial activity. Sinus tachycardia has P waves. Ventricular fibrillation is irregular
j j j j j j j j j j j j j j
and does not have a consistent QRS duration.
j j j j j j j j
DIF: Cognitive Level: Apply (application) REF: 794
j j j j j j
TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
5. The nurse notes that a patient's cardiac monitor shows that every other beat is earlier than expected, has
j j j j j j j j j j j j j j j j j j j
j no visible P wave, and has a QRS complex that is wide and bizarre in shape. How will the nurse document the
j j j j j j j j j j j j j j j j j j j j j
j rhythm?
a. Ventricular couplets
j j
b. Ventricular bigeminy
j j
c. Ventricular R-on-T phenomenon
j j j
d. Multifocal premature ventricular contractions - CORRECT ANSWER✔✔B
j j j j j j j
, Ventricular bigeminy describes a rhythm in which every other QRS complex is wide and bizarre looking. Pairs
j j j j j j j j j j j j j j j j
of wide QRS complexes are described as ventricular couplets. There is no indication that the premature
j j j j j j j j j j j j j j j j
ventricular contractions (PVCs) are multifocal or that the R-on-T phenomenon is occurring.
j j j j j j j j j j j j
DIF: Cognitive Level: Apply (application) REF: 799
j j j j j j
TOP: Nursing Process: Assessment MSC:
j j j j
Physiological Integrity j
6. A patient has a normal cardiac rhythm and a heart rate of 72 beats/minute. The nurse determines that the
j j j j j j j j j j j j j j j j j j j j
j P-R interval is 0.24 seconds. The most appropriate intervention by the nurse would be to
j j j j j j j j j j j j j j
a. notify the health care provider immediately.
j j j j j j
b. give atropine per agency dysrhythmia protocol.
j j j j j j
c. prepare the patient for temporary pacemaker insertion.
j j j j j j j
d. document the finding and continue to monitor the patient. - CORRECT ANSWER✔✔D
j j j j j j j j j j j j
First-degree atrioventricular (AV) block is asymptomatic and requires ongoing monitoring because it may
j j j j j j j j j j j j
progress to more serious forms of heart block. The rate is normal, so there is no indication that atropine is
j j j j j j j j j j j j j j j j j j j j
needed. Immediate notification of the health care provider about an asymptomatic rhythm is not
j j j j j j j j j j j j j j
necessary.
j
DIF: Cognitive Level: Apply (application) REF: 798
j j j j j j
TOP: Nursing Process: Implementation MSC:
j j j j
Physiological Integrity j
7. A patient who was admitted with a myocardial infarction experiences a 45-second episode of ventricular
j j j j j j j j j j j j j j j j
j tachycardia, then converts to sinus rhythm with a heart rate of 98 beats/minute. Which of the following
j j j j j j j j j j j j j j j j
j actions should the nurse take next?
j j j j j
a. Immediately notify the health care provider.
j j j j j j
