Chapter 43: Review of Hemodynamics

Chapter 43: Review of Hemodynamics

 

Complete Chapter Questions With Answers

 

Sample Questions Are Posted Below

 

MULTIPLE CHOICE

 

1. A patient is taking a beta₁-adrenergic drug to improve the stroke volume of the heart. The nurse caring for this patient knows that this drug acts by increasing:

a.	cardiac afterload.
b.	cardiac preload.
c.	myocardial contractility.
d.	venous return.

 

 

ANS:  C

Beta₁-adrenergic agents help increase the heart’s stroke volume by increasing myocardial contractility. Cardiac afterload is determined primarily by the degree of peripheral resistance caused by constriction of arterioles; increasing afterload would decrease stroke volume. Beta₁-adrenergic agents do not affect afterload. Cardiac preload is the amount of stretch applied to the cardiac muscle before contraction and is determined by the amount of venous return. Beta₁-adrenergic agents do not affect cardiac preload. Venous return is determined by the systemic filling pressure and auxiliary muscle pumps and is not affected by beta₁-adrenergic agents.

 

PTS:   1                    DIF:    Cognitive Level: Analysis                REF:   pp. 465-466

TOP:   Nursing Process: Evaluation

MSC:  NCLEX Client Needs Category: Physiologic Integrity: Physiologic Adaptation

 

2. A nurse is caring for a patient who is receiving a drug that causes constriction of arterioles. The nurse expects to observe which effect from this drug?

a.	Decreased stroke volume
b.	Increased stroke volume
c.	Decreased myocardial contractility
d.	Increased myocardial contractility

 

 

ANS:  A

Constriction of arterioles increases the load against which the heart must pump to eject blood. Increased constriction of arterioles would decrease, not increase, the stroke volume of the heart. Myocardial contractility is determined by the sympathetic nervous system, acting through beta₁-adrenergic receptors in the myocardium.

 

PTS:   1                    DIF:    Cognitive Level: Analysis                REF:   pp. 465-466

TOP:   Nursing Process: Assessment

MSC:  NCLEX Client Needs Category: Physiologic Integrity: Physiologic Adaptation

 

3. A patient with a history of hypertension is admitted for a procedure. If the patient’s arterial pressure decreases, which clinical manifestation would the nurse expect to see?

a.	Decreased heart rate
b.	Increased heart rate
c.	Decreased blood pressure
d.	Syncope

 

 

ANS:  B

When arterial pressure decreases, the vasoconstrictor center causes constriction of nearly all arterioles, leading to an increase in peripheral resistance, constriction of veins, increasing venous return, and subsequent acceleration of the heart rate. A decrease in arterial pressure would not cause a decrease in the heart rate or blood pressure, nor would it cause syncope.

 

PTS:   1                    DIF:    Cognitive Level: Application           REF:   p. 468

TOP:   Nursing Process: Assessment

MSC:  NCLEX Client Needs Category: Physiologic Integrity: Physiologic Adaptation

 

4. A nurse is teaching a nursing student how blood can return to the heart when pressure in the venous capillary beds is very low. Which statement by the student indicates a need for further teaching?

a.	“Constriction of small muscles in the venous wall increases venous pressure.”
b.	“Negative pressure in the left atrium draws blood toward the heart.”
c.	“Skeletal muscles relax to allow the free flow of blood.”
d.	“Venous valves help prevent the backflow of blood.”

 

 

ANS:  C

Skeletal muscle contraction, along with one-way venous valves, helps create an “auxiliary” venous pump that helps drive blood toward the heart. Constriction of small muscles in venous walls helps increase venous pressure. Negative pressure in the left atrium sucks blood toward the heart. Valves, which are one-way, work with the contraction of skeletal muscles to create a venous pump.

 

PTS:   1                    DIF:    Cognitive Level: Application           REF:   pp. 464-465

TOP:   Nursing Process: Assessment

MSC:  NCLEX Client Needs Category: Physiologic Integrity: Physiologic Adaptation