DSE Pulm

Pulmonology Cumulative Practice Exam

PANCE-Style Clinical Vignettes · Didactic Summative Review

Instructions: 50 questions, one best answer each. Suggested time: 60 minutes (about 70 seconds per question). Topics: COPD, asthma, respiratory infections, tuberculosis, lung neoplasm, pleural disease, pulmonary embolism and hypertension, interstitial lung disease, sleep apnea, ARDS, neonatal and pediatric lung disease. The answer key and rationales follow the questions.

1. A 66-year-old man with a 50 pack-year smoking history has chronic dyspnea. Post-bronchodilator spirometry shows FEV1/FVC 0.62 and FEV1 55% predicted. Which finding confirms the diagnosis of COPD?

A.  Post-bronchodilator FEV1/FVC less than 0.70

B.  Chest x-ray with hyperinflation

C.  FEV1 less than 80% predicted alone

D.  Increased DLCO

2. A 70-year-old woman with COPD has frequent dyspnea (group B) and uses albuterol as needed. Which is the best next step in maintenance therapy?

A.  Start long-term oral prednisone

B.  Add oral theophylline first

C.  Switch to ICS monotherapy

D.  Add a LABA plus LAMA combination

3. Which intervention has been shown to improve survival in COPD?

A.  Chronic azithromycin

B.  Inhaled corticosteroids in all patients

C.  Smoking cessation and long-term oxygen in hypoxemic patients

D.  Theophylline

4. A 68-year-old man with COPD has PaO2 of 52 mmHg on room air at rest. What is the appropriate management?

A.  Oral prednisone daily

B.  Oxygen only with exertion

C.  Nocturnal CPAP

D.  Long-term supplemental oxygen at least 15 hours per day

5. A 64-year-old man with COPD presents with increased dyspnea, increased sputum volume, and purulent sputum for 3 days. SpO2 is 89% on room air. Which regimen is most appropriate?

A.  IV methylprednisolone for 2 weeks

B.  Antibiotics only

C.  Short-acting bronchodilators, prednisone 40 mg for 5 days, and an antibiotic

D.  Beta-blocker and oxygen at 100%

6. A 35-year-old nonsmoker presents with early-onset emphysema and mildly elevated liver enzymes. Which test is most appropriate?

A.  Serum alpha-1 antitrypsin level

B.  Sweat chloride test

C.  Serum ACE

D.  ANA

7. A 22-year-old has episodic wheezing, nocturnal cough, and dyspnea triggered by exercise and cold air. Spirometry is normal today. What is the best next test?

A.  Chest CT

B.  Bronchoscopy

C.  Alpha-1 antitrypsin level

D.  Methacholine challenge

8. A 28-year-old with asthma uses albuterol 3 times a week and has night symptoms twice a month. Which best describes her asthma, and the preferred controller?

A.  Mild persistent; low-dose ICS or as-needed ICS-formoterol

B.  Intermittent; scheduled LABA monotherapy

C.  Severe persistent; omalizumab

D.  Moderate persistent; oral prednisone

9. A 30-year-old woman with asthma, nasal polyps, and wheezing after taking aspirin most likely has which condition?

A.  Samter triad (aspirin-exacerbated respiratory disease)

B.  Allergic bronchopulmonary aspergillosis

C.  Cystic fibrosis

D.  Churg-Strauss syndrome

10. A 19-year-old in the ED has severe asthma exacerbation, is speaking in single words, and PEF is 35% of predicted. Blood gas shows PaCO2 of 44 mmHg. What does the PaCO2 indicate?

A.  Hyperventilation from anxiety

B.  Impending respiratory failure

C.  Adequate ventilation

D.  Metabolic compensation

11. A 40-year-old with severe eosinophilic asthma remains uncontrolled on high-dose ICS-LABA and tiotropium. Eosinophil count is 600/µL. Which add-on is appropriate?

A.  Oral theophylline as a replacement

B.  Zafirlukast alone

C.  Mepolizumab

D.  Cromolyn

12. A 9-month-old has rhinorrhea, wheezing, tachypnea, and nasal flaring in January. Which is the treatment?

A.  Albuterol nebulization

B.  Oral amoxicillin

C.  Supportive care with oxygen and hydration

D.  Systemic steroids

13. A 2-year-old has a barking cough, inspiratory stridor, and low-grade fever. Neck x-ray shows subglottic narrowing. What is the best treatment?

A.  Oral amoxicillin

B.  Nebulized hypertonic saline

C.  Dexamethasone

D.  Albuterol

14. An unimmunized 4-year-old has abrupt fever, drooling, muffled voice, and sits in the tripod position. What is the priority?

A.  Secure the airway in a controlled setting

B.  Oral dexamethasone

C.  Throat examination with tongue depressor

D.  Lateral neck x-ray before any intervention

15. A 6-week-old unvaccinated infant has paroxysms of cough ending with a whoop and post-tussive emesis; the lymphocyte count is markedly elevated. What is the treatment?

A.  Azithromycin

B.  Oseltamivir

C.  Albuterol

D.  Amoxicillin

16. A 35-year-old previously healthy nonsmoker presents with 4 days of fever, productive cough, and a lobar infiltrate. He is hemodynamically stable with CURB-65 score of 0. Which is the best outpatient treatment?

A.  IV ceftriaxone and admission

B.  Levofloxacin first-line

C.  Amoxicillin 1 g three times daily or doxycycline

D.  Azithromycin alone in all regions

17. A 62-year-old with COPD and diabetes has CAP and is treated as an outpatient. Which regimen is recommended?

A.  Cephalexin

B.  Azithromycin monotherapy

C.  Amoxicillin monotherapy

D.  Amoxicillin-clavulanate plus a macrolide or doxycycline

18. A 55-year-old alcoholic man has fever and cough productive of thick, blood-tinged 'currant jelly' sputum with an upper-lobe infiltrate and bulging fissure. Which organism is most likely?

A.  Klebsiella pneumoniae

B.  Mycoplasma pneumoniae

C.  Streptococcus pneumoniae

D.  Legionella pneumophila

19. A 58-year-old man who stayed at a hotel with a hot tub has high fever, diarrhea, confusion, and hyponatremia with a patchy infiltrate. Which test and treatment are appropriate?

A.  Sputum AFB; isoniazid

B.  Urine Legionella antigen; azithromycin or a fluoroquinolone

C.  Cold agglutinins; amoxicillin

D.  Blood culture; vancomycin

20. A 32-year-old HIV-positive man with CD4 of 80 has progressive dyspnea, dry cough, and diffuse bilateral ground-glass opacities. LDH is elevated and PaO2 is 62 mmHg on room air. What is the treatment?

A.  TMP-SMX alone

B.  Azithromycin

C.  Fluconazole

D.  TMP-SMX plus prednisone

21. A hospitalized patient on a ventilator for 6 days develops fever and a new infiltrate. Which empiric regimen is most appropriate?

A.  Amoxicillin

B.  Oral doxycycline

C.  Azithromycin alone

D.  Anti-pseudomonal beta-lactam plus MRSA coverage

22. A 45-year-old immigrant has 4 weeks of cough, night sweats, and weight loss. Chest x-ray shows an upper-lobe cavitary lesion. What is the best next step?

A.  Start isoniazid alone

B.  Tuberculin skin test only

C.  Airborne isolation and sputum AFB smear and culture

D.  Discharge with outpatient follow-up

23. What is the standard initial treatment of active pulmonary tuberculosis?

A.  Isoniazid alone for 9 months

B.  Rifampin, isoniazid, pyrazinamide, and ethambutol for 2 months, then rifampin and isoniazid for 4 months

C.  Rifampin and ethambutol for 6 months

D.  Isoniazid and pyrazinamide for 2 months

24. A patient treated for tuberculosis develops numbness and tingling in both feet. Which agent is responsible and what prevents this?

A.  Rifampin; folate

B.  Pyrazinamide; vitamin B12

C.  Ethambutol; vitamin C

D.  Isoniazid; pyridoxine (vitamin B6)

25. A healthcare worker has a TB skin test with 11 mm induration, normal chest x-ray, and no symptoms. What is the diagnosis and treatment?

A.  Active TB; RIPE therapy

B.  Active TB; isoniazid alone for 6 months

C.  Not infected; repeat in 1 year

D.  Latent TB; rifampin for 4 months

26. A 62-year-old smoker has cough, weight loss, and a central cavitary mass; calcium is 13.2 mg/dL and PTH is low. Which tumor is most likely?

A.  Adenocarcinoma

B.  Small cell carcinoma

C.  Squamous cell carcinoma

D.  Carcinoid tumor

27. A 60-year-old smoker has a central lung mass with hyponatremia and low serum osmolality with inappropriately concentrated urine. Which is the most likely tumor and treatment?

A.  Large cell carcinoma; surgery

B.  Small cell carcinoma; chemotherapy and radiation

C.  Adenocarcinoma; EGFR inhibitor

D.  Squamous cell carcinoma; lobectomy

28. A 55-year-old woman who never smoked has a peripheral lung mass. Which is the most likely histology?

A.  Squamous cell carcinoma

B.  Adenocarcinoma

C.  Small cell carcinoma

D.  Mesothelioma

29. A 68-year-old smoker has right arm pain, ptosis, miosis, and anhidrosis on the right face. Which tumor location explains this?

A.  Superior sulcus (Pancoast) tumor

B.  Hilar mass

C.  Pleural mesothelioma

D.  Mediastinal lymphoma

30. A 62-year-old has a 30 pack-year history and quit 5 years ago. Which screening is recommended?

A.  Annual chest x-ray

B.  Annual low-dose CT scan

C.  Sputum cytology

D.  No screening because he quit

31. A 52-year-old has a 1.8 cm solitary pulmonary nodule with spiculated margins in the upper lobe. He smokes. Which is the next best step?

A.  PET-CT and/or tissue biopsy

B.  Empiric antibiotics for 6 weeks

C.  Reassurance

D.  Repeat chest x-ray in 1 year

32. A patient with heart failure has a pleural effusion. Thoracentesis: pleural/serum protein ratio 0.3, pleural/serum LDH ratio 0.4. What is the classification?

A.  Chylothorax

B.  Exudate

C.  Empyema

D.  Transudate

33. Pleural fluid shows pH 7.05, glucose 30 mg/dL, and WBC 30,000/µL with gram-positive cocci. What is the best treatment?

A.  Chest tube drainage and antibiotics

B.  Diuretics

C.  Repeat therapeutic thoracentesis only

D.  Observation

34. A 22-year-old tall thin man has sudden pleuritic chest pain and dyspnea. Chest x-ray shows a 4 cm apical pneumothorax, he is stable with SpO2 of 94%. What is the best management?

A.  Antibiotics

B.  Emergent needle decompression

C.  Needle aspiration or chest tube drainage

D.  Pleurodesis immediately

35. A trauma patient has hypotension, distended neck veins, absent breath sounds on the right, and tracheal deviation to the left. What is the immediate treatment?

A.  Intubation

B.  CT scan

C.  Chest x-ray

D.  Needle decompression

36. A 38-year-old woman on oral contraceptives has pleuritic chest pain and dyspnea. Wells score is 1 (PE unlikely). What is the next step?

A.  Heparin

B.  D-dimer

C.  V/Q scan

D.  CT pulmonary angiogram

37. A 55-year-old postoperative patient has tachycardia, hypoxia, and pleuritic pain; Wells score is 6. Creatinine is normal. Which is the best diagnostic test?

A.  D-dimer

B.  Echocardiogram

C.  CT pulmonary angiography

D.  Chest x-ray alone

38. A patient with PE is hypotensive (BP 80/50) with right ventricular strain on echo. Which is the best therapy?

A.  Inferior vena cava filter alone

B.  Systemic thrombolysis (alteplase)

C.  Warfarin alone

D.  Aspirin

39. A 45-year-old man has hemodynamically stable PE and no contraindications. Which is a preferred anticoagulant?

A.  Rivaroxaban or apixaban

B.  Warfarin alone starting immediately

C.  Clopidogrel

D.  Aspirin

40. A 35-year-old woman has exertional dyspnea, a loud P2, and right ventricular heave. Right heart catheterization shows mean pulmonary artery pressure of 38 mmHg with normal wedge pressure. Which is the treatment class for idiopathic PAH?

A.  Beta-blocker

B.  Endothelin receptor antagonist or PDE-5 inhibitor

C.  Loop diuretic alone

D.  ACE inhibitor

41. Which type of pulmonary hypertension is caused by chronic thromboembolic disease and is potentially curable?

A.  WHO Group 3

B.  WHO Group 4 (CTEPH)

C.  WHO Group 2

D.  WHO Group 1

42. A 66-year-old man has progressive dyspnea, dry cough, clubbing, and bibasilar 'Velcro' crackles. HRCT shows subpleural honeycombing. PFTs would most likely show which pattern?

A.  Increased TLC and decreased FEV1/FVC

B.  Normal FVC with decreased FEV1/FVC

C.  Increased DLCO

D.  Decreased FVC and TLC with normal or elevated FEV1/FVC and decreased DLCO

43. A 28-year-old Black woman has dry cough, bilateral hilar lymphadenopathy, erythema nodosum, and hypercalcemia. Biopsy would show which finding?

A.  Caseating granulomas

B.  Ferruginous bodies

C.  Noncaseating granulomas

D.  Reed-Sternberg cells

44. A 60-year-old retired shipyard worker has pleural plaques and lower-lobe fibrosis. He has an increased risk of which malignancy?

A.  Hepatocellular carcinoma

B.  Basal cell carcinoma

C.  Mesothelioma

D.  Squamous cell carcinoma of the head and neck

45. A 55-year-old sandblaster has upper-lobe nodules with eggshell calcification of hilar nodes. Which complication should be screened for?

A.  Tuberculosis

B.  Hepatocellular carcinoma

C.  Pulmonary embolism

D.  Mesothelioma

46. A 52-year-old obese man has loud snoring, witnessed apneas, daytime sleepiness, and resistant hypertension. What is the best diagnostic test and first-line treatment?

A.  Chest CT; tonsillectomy

B.  Spirometry; theophylline

C.  Overnight pulse oximetry; modafinil

D.  Polysomnography; CPAP

47. A patient with sepsis develops acute hypoxemic respiratory failure with bilateral infiltrates, PaO2/FiO2 of 150, and normal echocardiogram. What is the ventilator strategy that improves mortality?

A.  Zero PEEP

B.  Low tidal volume ventilation (6 mL/kg ideal body weight)

C.  Routine fluid resuscitation to maximize volume

D.  High tidal volume to normalize pCO2

48. A 28-week premature infant has grunting, retractions, and cyanosis shortly after birth. Chest x-ray shows diffuse ground-glass opacities with air bronchograms. Which treatment is indicated?

A.  Oral steroids

B.  Exogenous surfactant

C.  Indomethacin

D.  Antibiotics alone

49. A 4-year-old boy has recurrent pneumonias, steatorrhea, failure to thrive, and nasal polyps. Which test is diagnostic?

A.  Alpha-1 antitrypsin level

B.  Sweat chloride test

C.  Chest CT with contrast

D.  Serum IgE

50. A 2-year-old suddenly begins coughing and wheezing while eating peanuts. Chest x-ray shows unilateral hyperinflation with mediastinal shift away on expiration. What is the next step?

A.  Rigid bronchoscopy

B.  Albuterol nebulization

C.  Oral antibiotics

D.  Observation

Answer Key

Answer Rationales

1. A. Post-bronchodilator FEV1/FVC less than 0.70   [COPD]

COPD is confirmed by persistent airflow obstruction on post-bronchodilator spirometry (FEV1/FVC <0.70). Imaging supports but does not diagnose; DLCO is decreased in emphysema.

2. D. Add a LABA plus LAMA combination   [COPD]

GOLD group B: LABA + LAMA combination is preferred. ICS is reserved for frequent exacerbations with eosinophils ≥300. Chronic oral steroids are not recommended.

3. C. Smoking cessation and long-term oxygen in hypoxemic patients   [COPD]

Smoking cessation and LTOT (≥15 h/day for PaO2 ≤55 or SpO2 ≤88%) improve survival. Others improve symptoms or exacerbations.

4. D. Long-term supplemental oxygen at least 15 hours per day   [COPD]

LTOT is indicated for PaO2 ≤55 mmHg or SpO2 ≤88% (or PaO2 56-59 with cor pulmonale, edema, or Hct >55%).

5. C. Short-acting bronchodilators, prednisone 40 mg for 5 days, and an antibiotic   [COPD]

AECOPD: SABA ± SAMA, a 5-day oral steroid course, and antibiotics for purulent sputum or increased volume; target SpO2 88-92%.

6. A. Serum alpha-1 antitrypsin level   [COPD]

Alpha-1 antitrypsin deficiency: early (<45) panacinar lower-lobe emphysema with liver disease. Treat with augmentation therapy in selected patients.

7. D. Methacholine challenge   [Asthma]

When spirometry is normal but asthma is suspected, bronchoprovocation (methacholine) confirms hyperresponsiveness; a negative test makes asthma unlikely.

8. A. Mild persistent; low-dose ICS or as-needed ICS-formoterol   [Asthma]

SABA use more than 2 days/week but not daily = mild persistent (the most severe feature determines category). Low-dose ICS (or ICS-formoterol PRN). LABA monotherapy is never appropriate.

9. A. Samter triad (aspirin-exacerbated respiratory disease)   [Asthma]

Samter triad: asthma, nasal polyps, and aspirin/NSAID sensitivity; treat with leukotriene modifiers and avoid NSAIDs.

10. B. Impending respiratory failure   [Asthma]

In acute asthma, patients hyperventilate (low PaCO2). A normal or rising PaCO2 signals fatigue and impending respiratory failure; prepare for intubation.

11. C. Mepolizumab   [Asthma]

Severe eosinophilic asthma: anti-IL-5 (mepolizumab, benralizumab, reslizumab) or dupilumab. Omalizumab is anti-IgE for allergic asthma with elevated IgE.

12. C. Supportive care with oxygen and hydration   [Infection]

Bronchiolitis (RSV): supportive care only. Bronchodilators, steroids, and antibiotics are not recommended.

13. C. Dexamethasone   [Infection]

Croup (parainfluenza): the steeple sign; single-dose dexamethasone, plus racemic epinephrine if stridor at rest.

14. A. Secure the airway in a controlled setting   [Infection]

Epiglottitis is an airway emergency. Avoid agitating the child or examining the throat; intubate in the OR, then give ceftriaxone ± vancomycin.

15. A. Azithromycin   [Infection]

Pertussis: macrolides (azithromycin); isolation and prophylaxis for close contacts. Antibiotics shorten contagiousness but do not alter the cough course in later stages.

16. C. Amoxicillin 1 g three times daily or doxycycline   [Infection]

ATS/IDSA outpatient CAP without comorbidities: amoxicillin, doxycycline, or a macrolide only where resistance is <25%. Comorbidities: combination or respiratory fluoroquinolone.

17. D. Amoxicillin-clavulanate plus a macrolide or doxycycline   [Infection]

CAP with comorbidities: beta-lactam plus macrolide/doxycycline, or monotherapy with a respiratory fluoroquinolone.

18. A. Klebsiella pneumoniae   [Infection]

Klebsiella: alcoholics and diabetics, currant jelly sputum, upper-lobe abscess/cavitation. Pneumococcus gives rusty sputum.

19. B. Urine Legionella antigen; azithromycin or a fluoroquinolone   [Infection]

Legionella: GI symptoms, hyponatremia, elevated LFTs; diagnose with urine antigen. Treat with a macrolide or fluoroquinolone.

20. D. TMP-SMX plus prednisone   [Infection]

Pneumocystis jirovecii pneumonia: TMP-SMX; add corticosteroids if PaO2 <70 or A-a gradient ≥35. Prophylaxis at CD4 <200.

21. D. Anti-pseudomonal beta-lactam plus MRSA coverage   [Infection]

VAP/HAP: cover Pseudomonas and MRSA (piperacillin-tazobactam or cefepime plus vancomycin or linezolid) based on local antibiograms.

22. C. Airborne isolation and sputum AFB smear and culture   [TB]

Suspected active TB: airborne isolation (N95, negative-pressure room), three sputum samples for AFB and NAAT, then start RIPE therapy.

23. B. Rifampin, isoniazid, pyrazinamide, and ethambutol for 2 months, then rifampin and isoniazid for 4 months   [TB]

RIPE for 2 months followed by 4 months of RI. Isoniazid monotherapy is for latent TB.

24. D. Isoniazid; pyridoxine (vitamin B6)   [TB]

INH causes peripheral neuropathy (and hepatitis), prevented with B6. Ethambutol causes optic neuritis, pyrazinamide hyperuricemia, and rifampin orange fluids and CYP induction.

25. D. Latent TB; rifampin for 4 months   [TB]

≥10 mm is positive in healthcare workers. With negative CXR/no symptoms: latent TB, treated with 4R, 3HP, or INH 6-9 months.

26. C. Squamous cell carcinoma   [Neoplasm]

Squamous cell lung cancer: central, cavitary, and produces PTHrP, causing hypercalcemia.

27. B. Small cell carcinoma; chemotherapy and radiation   [Neoplasm]

Small cell lung cancer: SIADH, ACTH, Lambert-Eaton; usually disseminated at diagnosis, treated with chemotherapy and radiation, not surgery.

28. B. Adenocarcinoma   [Neoplasm]

Adenocarcinoma is the most common lung cancer overall and in nonsmokers; EGFR, ALK, and ROS1 mutations guide targeted therapy.

29. A. Superior sulcus (Pancoast) tumor   [Neoplasm]

Pancoast tumor compresses the sympathetic chain (Horner syndrome) and the brachial plexus (C8-T1 arm pain and weakness).

30. B. Annual low-dose CT scan   [Neoplasm]

USPSTF: annual LDCT for ages 50-80 with ≥20 pack-years who currently smoke or quit within 15 years.

31. A. PET-CT and/or tissue biopsy   [Neoplasm]

A large, spiculated nodule in a smoker is high risk for malignancy. Stable for 2 years or popcorn calcification suggest benign.

32. D. Transudate   [Pleura]

Light's criteria for exudate: protein ratio >0.5, LDH ratio >0.6, or pleural LDH >2/3 ULN. Transudates: HF, cirrhosis, nephrotic syndrome.

33. A. Chest tube drainage and antibiotics   [Pleura]

A complicated parapneumonic effusion or empyema (pH <7.2, low glucose) requires drainage plus antibiotics.

34. C. Needle aspiration or chest tube drainage   [Pleura]

Large primary spontaneous pneumothorax (>2-3 cm) or symptomatic: aspiration or a small-bore chest tube; small stable ones: observation with oxygen.

35. D. Needle decompression   [Pleura]

Tension pneumothorax is a clinical diagnosis. Decompress immediately (second intercostal space midclavicular or fifth ICS anterior axillary), then place a chest tube.

36. B. D-dimer   [PE]

Low pretest probability: D-dimer; if negative, PE is excluded. If positive or high probability, CTPA.

37. C. CT pulmonary angiography   [PE]

High probability: CTPA (V/Q scan if renal insufficiency, contrast allergy, or pregnancy).

38. B. Systemic thrombolysis (alteplase)   [PE]

Massive (high-risk) PE with hemodynamic instability: thrombolysis. IVC filter is for those with contraindications to anticoagulation.

39. A. Rivaroxaban or apixaban   [PE]

DOACs are first-line for stable PE. Warfarin requires heparin overlap for at least 5 days and INR ≥2 for 24 hours. Treat for at least 3 months.

40. B. Endothelin receptor antagonist or PDE-5 inhibitor   [Pulm HTN]

Group 1 PAH: ERA (bosentan, ambrisentan), PDE-5i (sildenafil), prostacyclins. CCBs only if vasoreactive.

41. B. WHO Group 4 (CTEPH)   [Pulm HTN]

Group 4 CTEPH: diagnose with V/Q scan and treat with lifelong anticoagulation and pulmonary thromboendarterectomy.

42. D. Decreased FVC and TLC with normal or elevated FEV1/FVC and decreased DLCO   [ILD]

Restrictive pattern in ILD: low volumes, preserved ratio, and reduced diffusing capacity. IPF is treated with nintedanib or pirfenidone.

43. C. Noncaseating granulomas   [ILD]

Sarcoidosis: noncaseating granulomas, elevated ACE; steroids for symptomatic or organ-threatening disease.

44. C. Mesothelioma   [ILD]

Asbestosis: pleural plaques, lower-lobe fibrosis, asbestos bodies; risk of mesothelioma and lung cancer (especially with smoking).

45. A. Tuberculosis   [ILD]

Silicosis increases the risk of TB; screen with IGRA/TST. Coal worker's pneumoconiosis also affects the upper lobes.

46. D. Polysomnography; CPAP   [Sleep]

OSA is diagnosed by polysomnography (AHI ≥5 with symptoms or ≥15). CPAP is first-line with weight loss.

47. B. Low tidal volume ventilation (6 mL/kg ideal body weight)   [ARDS]

ARDS: lung-protective ventilation with 6 mL/kg IBW tidal volumes, PEEP, plateau pressure <30, and prone positioning in severe cases.

48. B. Exogenous surfactant   [Neonatal]

Respiratory distress syndrome (hyaline membrane disease) from surfactant deficiency. Antenatal betamethasone prevents it.

49. B. Sweat chloride test   [CF]

CF: sweat chloride >60 mEq/L on two occasions plus CFTR genetics; Pseudomonas and S. aureus infections, pancreatic insufficiency.

50. A. Rigid bronchoscopy   [Aspiration]

Foreign body aspiration with air trapping: rigid bronchoscopy for removal in children; decubitus films can show air trapping.