PANCE Pulmonary System 3 — Questions and Answers
Question 1: A 70-year-old male presents with insidious onset dyspnea and a dry cough over 18 months. HRCT shows honeycombing with basal predominance. Pulmonary function tests reveal a restrictive pattern. Which diagnosis is most likely?
- Nonspecific interstitial pneumonia (NSIP)
- Idiopathic pulmonary fibrosis (IPF) (Correct answer)
- Cryptogenic organizing pneumonia (COP)
- Hypersensitivity pneumonitis
Correct answer: Idiopathic pulmonary fibrosis (IPF)
IPF classically presents in older males with progressive dyspnea, basal honeycombing on HRCT, and a restrictive PFT pattern with no identifiable cause.
Question 2: Which ventilator setting is most important in preventing ventilator-induced lung injury (VILI) in ARDS patients?
- FiO2 <0.40
- Tidal volume 6 mL/kg ideal body weight (Correct answer)
- PEEP >15 cmH2O
- Respiratory rate <12 breaths/min
Correct answer: Tidal volume 6 mL/kg ideal body weight
Low tidal volume ventilation (6 mL/kg IBW) as established by the ARDSnet trial is the most evidence-based intervention to reduce VILI and mortality.
Question 3: A 35-year-old flight attendant develops sudden-onset pleuritic chest pain and dyspnea after a long flight. CT pulmonary angiography confirms a pulmonary embolism. She has no bleeding risk factors. What is the first-line treatment?
- Unfractionated heparin infusion with warfarin bridge
- Rivaroxaban (Correct answer)
- Alteplase thrombolysis
- Inferior vena cava filter placement
Correct answer: Rivaroxaban
Direct oral anticoagulants such as rivaroxaban are now first-line for hemodynamically stable PE due to ease of use and non-inferiority to heparin/warfarin.
Question 4: A patient with known primary pulmonary hypertension develops worsening dyspnea. Echocardiogram shows RV systolic pressure of 80 mmHg. Which medication class acts by increasing cyclic GMP to cause pulmonary vasodilation?
- Endothelin receptor antagonists (bosentan)
- Phosphodiesterase-5 inhibitors (sildenafil) (Correct answer)
- Prostacyclin analogs (epoprostenol)
- Calcium channel blockers (nifedipine)
Correct answer: Phosphodiesterase-5 inhibitors (sildenafil)
PDE-5 inhibitors prevent breakdown of cGMP, sustaining NO-mediated pulmonary vasodilation and reducing pulmonary vascular resistance.
Question 5: Which of the following best differentiates central from obstructive sleep apnea on polysomnography?
- Apnea duration longer than 10 seconds
- Absence of respiratory effort during apneic episodes (Correct answer)
- Oxygen desaturation to less than 88%
- More than 5 events per hour of sleep
Correct answer: Absence of respiratory effort during apneic episodes
Central sleep apnea is defined by cessation of both airflow and respiratory effort, whereas obstructive events have persistent thoracoabdominal effort.
Question 6: A miner presents with progressive dyspnea and bilateral upper lobe fibrosis on chest X-ray. Biopsy shows collagen nodules with birefringent crystals. What is the diagnosis?
- Coal workers' pneumoconiosis
- Silicosis (Correct answer)
- Asbestosis
- Berylliosis
Correct answer: Silicosis
Silicosis presents with bilateral upper lobe nodular fibrosis, and birefringent silica crystals are seen on polarized microscopy of biopsy specimens.
Question 7: A 25-year-old with cystic fibrosis has chronic Pseudomonas aeruginosa colonization. Which inhaled antibiotic is approved for chronic suppressive therapy in this setting?
- Inhaled amphotericin B
- Inhaled tobramycin (Correct answer)
- Inhaled azithromycin
- Inhaled ciprofloxacin oral solution
Correct answer: Inhaled tobramycin
Inhaled tobramycin (TOBI) is FDA-approved for chronic suppressive therapy of P. aeruginosa in cystic fibrosis patients aged 6 years and older.
PANCE Pulmonary System 3
A 70-year-old male presents with insidious onset dyspnea and a dry cough over 18 months.
HRCT shows honeycombing with basal predominance.
Pulmonary function tests reveal a restrictive pattern.
Which diagnosis is most likely?