Hall: Guyton and Hall Textbook of Medical Physiology, 12th Edition
Chapter 42: Respiratory Insufficiency—Pathophysiology, Diagnosis, Oxygen Therapy
Test Bank
1. In patients with a chronic hypercapnia (elevated pCO2), the normal ______ drive to
breathe is replace with a ________ drive.
A. Hypoxic, hypercapnic
B. Hypercapnic, hypoxic
C. Apneustic, pneumotaxic
D. Pneumotaxic, apneustic
2. A chronic smoker has an arterial pO2 of 60 mmHg and an arterial pCO2 of 48. What will
happen to arterial pO2 and pCO2 if the patient is placed on 100% O2?
Arterial pO2 Arterial pCO2
A.
B.
C.
D.
3. Which parameter decreases with emphysema?
A. Alveolar pCO2
B. Cardiac output
C. Diffusion area
D. Pulmonary artery pressure
4. Oxygen therapy is most beneficial in which of the following situations? Lung function is
normal.
A. Anemia
B. CO2 retention (COPD)
C. Cyanide poisoning
D. High altitude
5. During severe pulmonary disease a stimulus for control of respiration is:
A. A decrease in arterial oxygen content
B. A decrease in arterial pCO2
C. A decrease in arterial PO2
Test Bank
42-2
D. An increase in arterial pH
6. Many patients with ventilation-perfusion inequality have low blood pO2 but no CO2
retention because:
A. The O2 and CO2 dissociation curves have different shapes
B. These patients have an increased blood flow
C. The diffusing capacity of CO2 is much higher than O2
D. There is hyperventilation due to the elevated pCO2
7. What is the most common cause of COPD?
A. Smoking
B. Occupational exposure
C. Environmental exposure
D. Genetic
E. Restrictive lung diseases
8. When a resting person breathes 100% oxygen in place of room air:
A. The oxygen content in normal blood is more than doubled
B. Systemic venous pO2 is higher than 40 mmHg
C. Mixed venous pO2 will be more than 100 mmHg
D. The quantity of CO2 added to the blood in systemic capillaries is significantly reduced
9. A patient complaints of shortness of breath; during the history you discover that he is
exposed to a variety of environmental insults at his job. Which of the following diseases
do you suspect?
A. Occupational asthma
B. Pulmonary fibrosis
C. Restrictive lung disease
D. We cannot tell without pulmonary function tests
10. A COPD patient, while breathing room air, has a systemic pCO2 of 65 mmHg and a pO2
of 40 mmHg. Supplemental oxygen is administered at a rate to increase pO2 to 55
mmHg, which resulted in pCO2 increasing to 70 mmHg. The supplemental O2:
A. Restored arterial dissolved O2 to normal
B. Did not change breathing
C. Reduced hypoxic stimulation of breathing
Test Bank
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D. Increased the pulmonary excretion of CO2