Chapter 20 Cardiac Output, Venous Return, and Their Regulation

Chapter 20  Cardiac Output, Venous Return, and Their Regulation

Complete Chapter Questions And Answers
 

Sample Questions

DIRECTIONS: Choose the BEST answer.

1. For the cardiac output curve defined by the solid line and the venous return curve defined by the dashed line (with equilibrium at point B), what is the resistance to venous return in units of mmHg/L/min?
A. 1.70
B. 1.40
C. 1.23
D. 0.65
E. 0.35

ANS: DD

2. A 40-year-old woman is hospitalized and has a severe anemia. This patient has a cardiac output of 12.5 L/min, oxygen consumption is 250 mL/min, and pulmonary artery oxygen concentration is 160 mL/L of blood, what is the pulmonary vein oxygen concentration in units of mL/L of blood?
A. 140
B. 150
C. 160
D. 180
E. 200

ANS: DD

3. Which of the following will cause a leftward shift in the cardiac output curve?
A. Surgically opening the thoracic cage
B. Placing a patient on a mechanical ventilator
C. Cardiac tamponade
D. Decreasing intrapleural pressure to -6.0 mmHg
E. Positive pressure breathing

ANS: DD

4. Which of the following is normally associated with a decreased resistance to venous return?
A. Hyperthyroidism
B. Increased venous resistance
C. Increased arteriolar resistance
D. Increased sympathetic output
E. Obstruction of veins

ANS: A

5. A 60-year-old woman is in the intensive care unit of a hospital and has a large A-V fistula. If this patient has a cardiac output of 10 L/min, oxygen consumption is 250 mL/min, and pulmonary vein oxygen concentration is 180 mL/L of blood, what is the pulmonary artery oxygen concentration in units of mL/L of blood?
A. 145
B. 155
C. 165
D. 185
E. 205

ANS: B