Deck 6: Evidence-Based Practice

Question 1

Afterload is influenced by arterial blood pressure, arterial distensibility, and arterial resistance.

Answer 1

True

Question 2

Each ventricle holds about 300 mL of blood when it is full. They normally eject about three fourths of this volume with each contraction.

Answer 2

False

Question 3

The two most common sites of atrioventricular (AV) block are the:

A) AV node and bundle branches.
B) atria and Purkinje fibers.
C) bundle of His and bundle branches.
D) bundle of His and Purkinje fibers.

Answer 3

AV node and bundle branches.

Question 4

The difference between second-degree type I and type II AV block is that with:

A) type I, the ventricular rhythm is regular.
B) type II, the PR interval is always less than 0.12 second in duration.
C) type I, the P waves occur irregularly.
D) type I, the PR interval becomes progressively longer until a P wave appears without a QRS complex.

Question 5

A heart rate that is too fast may be associated with:

A) junctional rhythm and atrial flutter.
B) second-degree AV block and atrial fibrillation.
C) idioventricular rhythm and ventricular tachycardia.
D) supraventricular tachycardias and ventricular tachycardia.

Question 6

In a third-degree AV block:

A) the atrial rhythm (P-P interval) is irregular.
B) the ventricular rhythm (R-R interval) is irregular.
C) the PR interval lengthens until a P wave appears with no QRS complex.
D) there is no PR interval because the atria and ventricles beat independently of each other.

Question 7

Which of the following types of second-degree AV block is most likely to rapidly progress rapidly to a third-degree AV block without warning?

A) Second-degree AV block type I
B) Second-degree AV block type II

Question 8

Preload is:

A) the force exerted on the walls of the ventricles at the end of diastole.
B) the volume of blood expelled by the ventricles of the heart per minute.
C) the resistance against which the left ventricle must eject its blood volume during contraction.
D) the pressure exerted by the circulating blood volume on the walls of the arteries, veins, and the chambers of the heart.

Question 9

Absolute hypovolemia is a term used to describe:

A) an actual fluid deficit.
B) a change in tank size due to vasodilation from any cause or redistribution of body fluid to third spaces.

Question 10

A third-degree AV block associated with an anterior MI is usually preceded by:

A) second-degree AV block type II or an intraventricular conduction delay.
B) first-degree AV block or second-degree AV block type I.
C) second-degree AV block type I or ventricular tachycardia.
D) first-degree AV block or an intraventricular conduction delay.

Question 11

As the left ventricle fails,

A) blood builds up in the lungs.
B) the liver enlarges and becomes tender.
C) generalized edema of the entire body develops.
D) blood backs up into the superior and inferior venae cavae.

Question 12

When AV block is associated with an inferior wall infarction and produces a narrow QRS complex, the block is probably located in the:

A) atria.
B) AV node.
C) bundle branches.
D) Purkinje fibers.

Question 13

Cardiac output is determined by:

A) heart rate × stroke volume.
B) blood pressure × heart rate.
C) systolic + diastolic pressure.
D) stroke volume × blood pressure.

Question 14

Possible causes of relative hypovolemia include:

A) spinal injury and anaphylaxis.
B) hemorrhage and third-space loss.
C) phlebotomy and reduced fluid intake.
D) drugs that alter vascular tone, vomiting, and diarrhea.

Question 15

When AV block is associated with an anterior wall infarction and produces a wide QRS complex, the block is probably located in the:

A) SA node.
B) AV node.
C) bundle branches.
D) atria.

Question 16

Which of the following statements is INCORRECT regarding a first-degree AV block?

A) First-degree AV block that occurs with acute myocardial infarction should be monitored closely.
B) First-degree AV block may be a normal finding in individuals with no history of cardiac disease.
C) Medications such as procainamide, beta-blockers, calcium channel blockers, digitalis, and amiodarone can cause a first-degree AV block.
D) First-degree AV block is usually an indication for a permanent pacemaker.

Question 17

List four complications associated with MI.

Question 18

List the cardiovascular system components necessary to ensure normal body tissue perfusion.

Question 19

Define cardiogenic shock.