Pulmonology — MCQs

Pulmonology Indian Medical PG Practice Questions and MCQs

Question 861: Which of the following is used for improving the long-term prognosis in COPD with resting hypoxemia?

A. Oxygen (Correct Answer)
B. Beta-2 agonist
C. Inhaled steroids
D. Systemic steroids

Explanation: ***Oxygen*** - **Long-term oxygen therapy** (LTOT) in patients with COPD and resting hypoxemia significantly improves **survival**, quality of life, and exercise capacity [2], [3]. - It reduces the risk of developing **pulmonary hypertension** and **cor pulmonale** [3]. *Beta-2 agonist* - **Short-acting** and **long-acting beta-2 agonists** are bronchodilators used to relieve symptoms like breathlessness by relaxing airways [1]. - While they improve symptoms and exercise tolerance, they do not impact the **long-term prognosis** or survival in COPD [1]. *Inhaled steroids* - **Inhaled corticosteroids** (ICS) are primarily used to reduce the frequency of **exacerbations** in patients with severe COPD. - They do not directly improve **long-term survival** or alter the progression of lung function decline. *Systemic steroids* - **Systemic corticosteroids** are used for short-term treatment of acute COPD exacerbations to reduce inflammation. - **Chronic use** is associated with significant side effects and does not improve the long-term prognosis or survival in stable COPD.

Question 862: Right middle lobe syndrome (Middle lobe syndrome) most commonly affects which lobe of the lung?

A. Right middle lobe (Correct Answer)
B. Right lower lobe
C. Left upper lobe
D. Left lower lobe

Explanation: ***Right middle lobe*** - **Right middle lobe syndrome** is, by definition, a collapse and consolidation of the **right middle lobe** of the lung. - This syndrome is characterized by recurrent or persistent atelectasis and/or pneumonitis specifically in the **right middle lobe** due to its unique anatomical features [1]. *Right lower lobe* - The **right lower lobe** is a distinct anatomical area of the lung and is not directly involved in **right middle lobe syndrome** [1]. - While it can be affected by other lung pathologies, **right middle lobe syndrome** specifically impacts the middle lobe. *Left upper lobe* - The **left upper lobe** is located in the left lung and is not associated with the **right middle lobe syndrome** [1]. - Its anatomy and associated pathologies are separate from those affecting the middle lobe of the right lung. *Left lower lobe* - Similar to the left upper lobe, the **left lower lobe** belongs to the left lung and is not involved in **right middle lobe syndrome**. - Lung conditions affecting the **left lower lobe** would be distinct from this syndrome.

Question 863: pH 7.24, PaO2 55 mm Hg, PaCO2 55 mm Hg, and HCO3- 30 mEq/L are consistent with which acid-base disorder?

A. Metabolic acidosis
B. Respiratory acidosis (Correct Answer)
C. Metabolic alkalosis
D. Respiratory alkalosis

Explanation: ***Respiratory acidosis*** - The **low pH (7.24)** indicates acidosis [1]. The **elevated PaCO2 (55 mm Hg)**, which is an acid, is primarily responsible for this drop in pH, indicating a respiratory problem [1]. - The **elevated HCO3- (30 mEq/L)** suggests a **renal compensatory response** to chronic respiratory acidosis, attempting to buffer the excess acid [2]. *Metabolic acidosis* - This would be characterized by a **low pH** and a **low bicarbonate (HCO3-)** level, which is not seen here as HCO3- is elevated [1]. - While there is acidosis, the primary driver is the elevated PaCO2, not a fall in bicarbonate. *Metabolic alkalosis* - This condition would present with a **high pH** and an elevated bicarbonate (HCO3-) level [3]. The given pH is low, indicating acidosis. - The elevated bicarbonate alone is often a **compensatory mechanism** rather than the primary disorder [3]. *Respiratory alkalosis* - This would involve a **high pH** and a **low PaCO2**, indicating hyperventilation [1]. The given pH is low, and PaCO2 is elevated. - This patient is hypoventilating, leading to CO2 retention and acidosis, not alkalosis [1].

Question 864: Blood gas measurements of a patient show the following values: pH 7.2, pCO2 80 mm Hg, and pO2 46 mm Hg. Which of the following could be the most probable diagnosis?

A. Acute exacerbation of COPD (Correct Answer)
B. Acute bronchospasm
C. Pulmonary embolism
D. Chronic pneumonia

Explanation: ***Acute exacerbation of COPD*** - The patient presents with **respiratory acidosis** (pH 7.2, normal 7.35-7.45) and **hypercapnia** (pCO2 80 mm Hg, normal 35-45 mm Hg), combined with severe **hypoxemia** (pO2 46 mm Hg, normal 80-100 mm Hg) [2]. - This pattern is highly indicative of an acute exacerbation of **Chronic Obstructive Pulmonary Disease**, where worsening airflow obstruction leads to inadequate alveolar ventilation and impaired gas exchange; clinical evidence suggests long-term oxygen therapy can decrease mortality in these chronic patients [1]. *Acute bronchospasm* - While acute bronchospasm can cause hypoxemia and hypercapnia, the degree of hypercapnia (pCO2 80 mm Hg) seen here is typically more severe and prolonged than commonly observed in isolated bronchospasm. Indications for assisted ventilation in severe asthma include a rising PaCO2 above 45 mmHg [3]. - Acute bronchospasm would likely result in less pronounced acidosis and more rapid response to bronchodilator therapy, which isn't described. *Pulmonary embolism* - Pulmonary embolism typically causes **hypoxemia** and **hypocapnia** (low pCO2) due to reflex hyperventilation in response to V/Q mismatch, which contradicts the presented blood gas values [2]. - The primary defect in pulmonary embolism is an obstruction of blood flow, not a global ventilation impairment leading to severe hypercapnia. *Chronic pneumonia* - Chronic pneumonia can cause **hypoxemia** due to V/Q mismatch or shunting, but it generally leads to **hypocapnia** or normal pCO2 if the patient is able to compensate by increasing ventilation [2]. - Severe hypercapnia (pCO2 80 mm Hg) with acute acidosis is less typical for uncomplicated chronic pneumonia, unless it's a very advanced or acute severe presentation with respiratory muscle fatigue.

Question 865: Pulmonary embolism is seen in all except?

A. Oral contraception
B. Old age
C. Fanconi anemia (Correct Answer)
D. Paroxysmal nocturnal hemoglobinuria

Explanation: ***Fanconi anemia*** - **Fanconi anemia** is a genetic disorder characterized by **bone marrow failure**, physical abnormalities, and an increased risk of cancer. - It does **not typically involve an increased risk of pulmonary embolism** as a primary manifestation; instead, its complications relate to cytopenias and malignancy. *Paroxysmal nocturnal hemoglobinuria* - **Paroxysmal nocturnal hemoglobinuria (PNH)** is strongly associated with **thrombosis**, including pulmonary embolism, due to acquired defects in the PIGA gene leading to complement-mediated red blood cell lysis. - The loss of **GPI-anchored proteins** (CD55 and CD59) on blood cells makes them susceptible to complement attack, promoting a prothrombotic state. *Oral contraception* - **Oral contraceptives**, particularly those containing **estrogen**, significantly increase the risk of venous thromboembolism, including pulmonary embolism. - Estrogens increase the synthesis of **clotting factors** and decrease natural anticoagulants. *Old age* - **Advanced age** is a well-established risk factor for **venous thromboembolism (VTE)**, including pulmonary embolism. - This is due to age-related changes such as reduced mobility, increased prevalence of comorbidities, and altered coagulation profiles.

Question 866: All are causes of pulmonary hypertension except which of the following?

A. High altitude
B. Fenfluramine
C. Morbid obesity
D. Hyperventilation (Correct Answer)

Explanation: ***Hyperventilation*** - **Hyperventilation** leads to a decrease in arterial carbon dioxide (PaCO2), causing **respiratory alkalosis** [1]. - This alkalosis induces **pulmonary vasodilation**, which tends to decrease rather than increase pulmonary arterial pressure. *Morbid obesity* - **Morbid obesity** often leads to **obesity hypoventilation syndrome (OHS)**, characterized by chronic hypoxemia and hypercapnia. - The resulting **chronic hypoxemia** causes sustained pulmonary vasoconstriction, leading to pulmonary hypertension. *High altitude* - Living at **high altitude** exposes individuals to **chronic hypoxia** due to lower atmospheric partial pressure of oxygen [3]. - This triggers **hypoxic pulmonary vasoconstriction** as a physiological response, which over time can remodel the pulmonary vasculature and lead to pulmonary hypertension [2]. *Fenfluramine* - **Fenfluramine** is an appetite suppressant that was historically linked to the development of pulmonary hypertension. - It causes an increase in pulmonary vascular resistance through various mechanisms, including enhancing the release and inhibiting the reuptake of **serotonin**, a potent pulmonary vasoconstrictor.

Question 867: Which condition is associated with the development of a bovine cough?

A. Laryngeal adenoidectomy
B. Acute epiglotitis
C. Tracheitis (Correct Answer)
D. Antibiotics

Explanation: ***Tracheitis*** - **Tracheitis** involves inflammation of the trachea, which can lead to a characteristic **bovine cough** due to irritation and narrowing of the airway [3]. - The cough is often **deep, harsh**, and **nonproductive**, resembling the sound made by a cow [2]. *Acute epiglotitis* - Acute epiglottitis typically presents with a **muffled voice**, **stridor**, and **difficulty swallowing**, not a bovine cough [2]. - It is an emergent condition due to potential **airway obstruction** at the level of the epiglottis. *Laryngeal adenoidectomy* - Laryngeal adenoidectomy is not a recognized medical procedure; adenoids are located in the **nasopharynx**. - A laryngeal procedure would affect the voice but is not associated with a **bovine cough** [1]. *Antibiotics* - Antibiotics are a **treatment** for bacterial infections, not a condition that causes a bovine cough. - They are used to address the underlying bacterial cause of conditions like **bacterial tracheitis**.

Question 868: In acute pulmonary embolism, which among the following is the most frequent ECG finding?

A. Right axis deviation
B. S1Q3T3 pattern
C. P. pulmonale
D. Sinus tachycardia (Correct Answer)

Explanation: ***Sinus tachycardia*** - **Sinus tachycardia** is the most frequent ECG finding in acute pulmonary embolism, seen in up to 40% of cases [1]. - It reflects the body's compensatory response to hypoxemia and decreased cardiac output. *S1Q3T3 pattern* - The classic **S1Q3T3 pattern** (S wave in lead I, Q wave in lead III, inverted T wave in lead III) is specific for acute right heart strain but is only found in approximately 10-20% of cases [1]. - It indicates more significant right ventricular dysfunction and is not the most frequent finding. *P. pulmonale* - **P. pulmonale**, characterized by tall, peaked P waves in leads II, III, and aVF, suggests **right atrial enlargement** due to chronic lung disease or pulmonary hypertension [1]. - While it can be seen in severe, prolonged right heart strain, it is much less common in acute PE than sinus tachycardia. *Right axis deviation* - **Right axis deviation** indicates **right ventricular hypertrophy** or acute right heart strain. - Like the S1Q3T3 pattern, it is a sign of more significant right heart involvement and is not as common as sinus tachycardia in all cases of acute PE [1].

Question 869: Which of the following best describes the arterial blood gas findings in type II respiratory failure?

A. Low pO2 and low pCO2
B. Normal pO2 and high pCO2
C. Low pO2 and normal pCO2
D. Low pO2 and high pCO2 (Correct Answer)

Explanation: ***Low pO2 and high pCO2*** - Type II respiratory failure is characterized by **hypoxemia** (low pO2) and **hypercapnia** (high pCO2), indicating a failure of both oxygenation and ventilation [1]. - This condition arises when the respiratory system cannot adequately remove carbon dioxide, leading to its accumulation in the blood [2]. *Low pO2 and low pCO2* - This pattern would typically suggest **compensated metabolic acidosis** or a response to profound hypoxemia with hyperventilation, not primary respiratory failure. - While there is hypoxemia, the low pCO2 indicates efficient or excessive CO2 removal, which is contrary to the definition of type II respiratory failure. *Normal pO2 and high pCO2* - A normal pO2 with high pCO2 is unlikely in true respiratory failure, as **hypoxemia** is a defining feature of any respiratory failure type [1]. - Isolated hypercapnia without hypoxemia would suggest a unique form of ventilation-perfusion mismatch that is not characteristic of respiratory failure. *Low pO2 and normal pCO2* - This description aligns with **Type I respiratory failure**, which is characterized by **hypoxemia** without significant hypercapnia or with normal pCO2 [1]. - In Type I, the primary issue is impaired oxygenation, while CO2 removal (ventilation) might still be adequate [1].

Question 870: Which of the following conditions is least likely to cause pneumothorax?

A. Marfan syndrome
B. Assisted ventilation
C. Eosinophilic granuloma
D. Bronchopulmonary Aspergillosis (Correct Answer)

Explanation: ***Bronchopulmonary Aspergillosis*** - Allergic bronchopulmonary aspergillosis (ABPA) is a hypersensitivity reaction to *Aspergillus* species, primarily causing **bronchospasm**, **mucus plugging**, and **bronchiectasis**, rarely leading to pneumothorax [1]. - While it can cause significant lung damage, **pneumothorax** is not a characteristic or common complication, unlike the other conditions listed. *Marfan syndrome* - Patients with **Marfan syndrome** have connective tissue abnormalities, including those affecting the pleura and lung parenchyma. - This predisposition can lead to the formation of **apical blebs and bullae**, which are prone to rupture and cause **spontaneous pneumothorax** [2]. *Assisted ventilation* - **Positive pressure ventilation**, especially with high pressures or volumes, can cause barotrauma or volutrauma to the lungs [2]. - This can lead to alveolar rupture, resulting in **pneumothorax**, particularly in patients with pre-existing lung disease or those requiring high ventilatory support. *Eosinophilic granuloma* - Also known as **pulmonary Langerhans cell histiocytosis**, this condition involves the infiltration of the lungs by Langerhans cells. - It often leads to the formation of **cysts and nodules**, which can rupture and cause recurrent **spontaneous pneumothorax**.

Practice by Chapter

Obstructive Airway Diseases (Asthma, COPD)

Practice Questions

Interstitial Lung Diseases

Practice Questions

Pulmonary Infections

Practice Questions

Pulmonary Vascular Diseases

Practice Questions

Pleural Diseases

Practice Questions

Sleep-Disordered Breathing

Practice Questions

Respiratory Failure

Practice Questions

Mediastinal Disorders

Practice Questions

Occupational Lung Diseases

Practice Questions

Pulmonary Function Testing

Practice Questions

Bronchiectasis and Cystic Fibrosis

Practice Questions

Lung Cancer Approach

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free