Chapter 35: Dysrhythmias Exam With
Correct Solutiuons.
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 patients
j j j j j
a. P wave.
j j j
b. Q wave.
j j j
c. P-R interval.
j j j
d. QRS complex. - CORRECT ANSWER✔✔a. P wave.
j j j 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
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
method will be best to use?
j j 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 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 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 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. Use the 3-second markers to count the number of QRS complexes in 6 seconds
j j j j j j j j j j j j j j j j
and multiply by 10.
j j 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
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
rate of _____ beats/minute.
j 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 j
d. 60 to 100 - CORRECT ANSWER✔✔c. 40 to 60
j j j j 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
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
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 patients cardiac
j j j j j j j j j j j j j j j j
rhythm as
j j j
a. atrial flutter.
j j j
Correct Solutiuons.
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 patients
j j j j j
a. P wave.
j j j
b. Q wave.
j j j
c. P-R interval.
j j j
d. QRS complex. - CORRECT ANSWER✔✔a. P wave.
j j j 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
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
method will be best to use?
j j 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 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 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 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. Use the 3-second markers to count the number of QRS complexes in 6 seconds
j j j j j j j j j j j j j j j j
and multiply by 10.
j j 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
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
rate of _____ beats/minute.
j 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 j
d. 60 to 100 - CORRECT ANSWER✔✔c. 40 to 60
j j j j 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
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
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 patients cardiac
j j j j j j j j j j j j j j j j
rhythm as
j j j
a. atrial flutter.
j j j
