CHAPTER 15: CARDIOVASCULAR THERAPEUTIC MANAGEMENT {Urden: Critical Care Nursing, 9th Edition}

C HAPTER 15: C ARDIOVASCULAR
T HERAPEUTIC M ANAGEMENT
Urden: Critical Care Nursing, 9th Edition



MULTIPLE CHOICE


1. A transvenous pacemaker is inserted through the right subclavian vein and
threaded into the right ventricle. Th e pacemaker is placed on demand at a
rate of 70. What is the three letter code for this pacing mode?
a. VVI
b. AOO
c. DDD
d. VAT



ANS: A



The original code is based on three categories, each represented by a
letter. The first letter refers to the cardiac chamber that is paced. The
second letter designates which chamber is sensed, and the third letter
indicates the pacemaker’s response to the sensed event. A VVI
pacemaker paces the ventricle when the pacemaker fails to sense an
intrinsic ventricular depolarization.



PTS: 1 DIF: Cognitive Level: Understanding REF: p.
362 | Table 15 -2 OBJ: Nursing Process Step: Intervention
TOP: Cardiovascular MSC: NC LEX: Physiologic
Integrit y

,2. A patient is connected to an external temporary pulse generator. What
does the sensitivit y control regulate?
a. The time interval between the atrial and ventricular pacing stimuli
b. The amount of electrical current and is measured in milliamperes
c. The abilit y of the pacemaker to detect the heart's intrinsic electrical
activit y
d. The number of impulses that can be delivered to the heart per
minute



ANS: C



The sensitivit y control regulates the ability of the pacemaker to detect
the heart’s intrinsic electrical activit y. Sensitivit y is measured in
millivolts (mV) and determines the size of the intracardia c signal that
the generator will recognize.



PTS: 1 DIF: Cognitive Level: Remembering REF: p. 363
OBJ: Nursing Process Step: Intervention TOP:
Cardiovascular MSC: NC LEX: Physiologic Integrit y



3. When anal yzing the electrocardiogram (ECG) strip of the p atient with a
pacemaker, the nurse notices there is a spike before each QRS complex.
What is this phenomenon indicative of?
a. 60-cycle electrical interference; check equipment
b. Pacing artifact; the pacemaker is sensing and capturing
c. Electrical artifact; the p acemaker is not sensing
d. Patient movement; check electrodes



ANS: B

, The pacing artifact is the spike that is seen on the electrocardiographic
tracing as the pacing stimulus is delivered to the heart. A P wave is
visible after the pacing artifact if the atr ium is being paced. Similarl y,
a QRS complex follows a ventricular pacing artifact. With dual -
chamber pacing, a pacing artifact precedes both the P wave and the
QRS complex.



PTS: 1 DIF: Cognitive Level: Appl ying REF: p. 363 |
Figure 15 -4B OBJ: Nursing Process Step: Intervention
TOP: Cardiovascular MSC: NC LEX: Physiologic
Integrit y



4. A patient is undergoing ventricular pacing via a transvenous pacing lead.
The nurse notes a pacing artifact, but it is not followed by a QRS on the
electrocardiogram (ECG) monitoring. Which nursing intervention may
correct this situation?
a. Position the patient on the left side
b. Decrease the milliamperes as ordered
c. Increase the rate as ordered
d. Monitor the patient in a different lead



ANS: A



The patient is experiencing “loss o f capture,” which most often can be
attributed either to displacement of the pacing electrode or to an
increase in threshold as a result of drugs, metabolic disorders,
electrol yte imbalances, or fibrosis or m yocardial ischemia at the site of
electrode placement. In many cases, increasing the output milliamperes