Question 1

Many patients with ventilation-perfusion inequality have low blood $\mathrm { pO } _ { 2 }$ but no $\mathrm { CO } _ { 2 }$ retention because of which of the following?
A. The $\mathrm { O } _ { 2 }$ and $\mathrm { CO } _ { 2 }$ dissociation curves have different shapes
B. These patients have an increased blood flow
C. The diffusing capacity of $\mathrm { CO } _ { 2 }$ is much higher than $\mathrm { O } _ { 2 }$
D. There is hyperventilation due to the elevated $\mathrm { pCO } _ { 2 }$

Accepted Answer

C

Question 2

When a resting person breathes $100 \%$ oxygen in place of room air, which of the following occurs?
A. The oxygen content in normal blood is more than doubled
B. Systemic venous $\mathrm { pO } _ { 2 }$ is higher than $40 \mathrm {~mm} \mathrm { Hg }$
C. Mixed venous $\mathrm { pO } _ { 2 }$ will be more than $100 \mathrm {~mm} \mathrm { Hg }$
D. The quantity of $\mathrm { CO } _ { 2 }$ added to the blood in systemic cap illaries is significantly reduced

Accepted Answer

C

Question 3

Oxygen therapy is most beneficial in which of the following situations? (Lung function is normal.)

Accepted Answer

Oxygen therapy is most beneficial in high altitude situations where the body is at a decreased oxygen level. In normal lung function, oxygen saturation is already adequate and oxygen therapy may cause harm rather than benefit. Anemia is a condition where the red blood cell count or hemoglobin level is low and may require specific treatments. CO₂ retention in chronic obstructive pulmonary disease requires a different type of treatment to eliminate the excess CO₂ in the body. Cyanide poisoning requires specific antidotes to prevent harm to the body.

Question 4

A 54-year-old woman with advanced emphysema from long-term cigarette smoking is admitted to the hospital for shortness of breath. She is diagnosed with pulmonary hypertension. Her arterial blood gases are: $\begin{array} { l } 
\mathrm { PO } _ { 2 } = 75 \mathrm {~mm} \mathrm { Hg } \
\mathrm { PCO } _ { 2 } = 45 \mathrm {~mm} \mathrm { Hg } \
\mathrm { pH } = 7.35
\end{array}$
What is the cause of her pulmonary hypertension?
A. Increased alveolar $\mathrm { pCO } _ { 2 }$
B. Increased sympathetic tone
C. Decreased alveolar $\mathrm { pO } _ { 2 }$
D. Decreased pulmonary capillary number

Accepted Answer

The answer of A 54-year-old woman with advanced emphysema from...

Question 5

A chronic smoker has an arterial $\mathrm { pO } _ { 2 }$ of $60 \mathrm {~mm} \mathrm { Hg }$ and an arterial $\mathrm { pCO } _ { 2 }$ of 48 . What will happen to arterial $\mathrm { pO } _ { 2 }$ and $\mathrm { pCO } _ { 2 }$ if the patient is placed on $100 \%$ oxygen?
$\begin{array} { l  } 
& \text { Arterial } \mathrm{pO}_{2}&\text { Arterial } \mathrm{pCO}_{2}\
A.&↑&↓\
B.&↓&↓\
C.&↑&↑\
D.&↓&↑\
\end{array}$

Accepted Answer

The answer of A chronic smoker has an arterial \(\mathrm...

Question 6

What is the most common cause of chronic obstructive pulmonary disease?

Accepted Answer

Smoking is the most common cause of chronic obstructive pulmonary disease (COPD), accounting for 80-90% of all cases. Occupational and environmental exposures can also contribute to COPD, but to a lesser extent. Genetic factors can predispose individuals to COPD, but they are not the primary cause. Restrictive lung diseases are a separate category of respiratory conditions that are characterized by reduced lung volume and capacity, rather than obstruction of air flow.

Question 7

A patient reports 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?

Accepted Answer

The answer of A patient reports shortness of breath. During...

Question 8

A patient with chronic obstructive pulmonary disease, while breathing room air, has a systemic $\mathrm { pCO } _ { 2 }$ of $65 \mathrm {~mm} \mathrm { Hg }$ and a $\mathrm { pO } _ { 2 }$ of $40 \mathrm {~mm} \mathrm { Hg }$. Supplemental oxygen is administered at a rate to increase $\mathrm { pO } _ { 2 }$ to $55 \mathrm {~mm} \mathrm { Hg }$, which resulted in $\mathrm { pCO } _ { 2 }$ increasing to $70 \mathrm {~mm} \mathrm { Hg }$. The supplemental $\mathrm { O } _ { 2 }$ did which of the following?
A. Restored arterial dissolved $\mathrm { O } _ { 2 }$ to normal
B. Did not change breathing
C. Reduced hypoxic stimulation of breathing
D. Increased the pulmonary excretion of $\mathrm { CO } _ { 2 }$

Accepted Answer

The answer of A patient with chronic obstructive pulmonary disease,...

Quiz 43: Respiratory Insufficiencypathophysiology, Diagnosis, Oxygen Therapy

Oxygen therapy is most beneficial in which of the following situations? (Lung function is normal.)

What is the most common cause of chronic obstructive pulmonary disease?

A patient reports 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?