Pulmonary System Disorders Flashcards
7 cards from real Physician Assistant practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Pulmonary System Disorders flashcards as text
A 55-year-old smoker presents with progressive dyspnea, barrel chest, and decreased breath sounds bilaterally. Spirometry shows FEV1/FVC of 0.58. Which pathophysiologic mechanism best explains the air trapping?
Answer: Loss of elastic recoil causing dynamic airway collapse
In emphysema, destruction of alveolar walls reduces elastic recoil, causing small airways to collapse during exhalation and trapping air distally.
A patient with a known pulmonary embolism develops sudden worsening of hypoxemia despite anticoagulation. Which mechanism most directly causes hypoxemia in acute PE?
Answer: Ventilation-perfusion mismatch with increased dead space
PE creates high V/Q areas (dead space) where ventilation occurs without perfusion, and can also cause atelectasis leading to low V/Q areas, both worsening oxygenation.
A 30-year-old with cystic fibrosis presents with increased sputum production and worsening FEV1. Sputum culture grows Pseudomonas aeruginosa. Which antibiotic combination is most appropriate for an acute exacerbation?
Answer: Piperacillin-tazobactam and tobramycin
Anti-pseudomonal beta-lactam plus an aminoglycoside provides synergistic coverage against Pseudomonas in CF exacerbations and helps prevent resistance.
A 68-year-old with a 6 cm solitary pulmonary nodule has a PET scan showing high SUV uptake. CT-guided biopsy reveals adenocarcinoma. Which staging workup is MOST critical before surgical planning?
Answer: Brain MRI and mediastinoscopy
Brain MRI detects occult CNS metastases and mediastinoscopy evaluates mediastinal lymph node involvement, both critical for determining resectability in NSCLC.
A patient with sarcoidosis has bilateral hilar lymphadenopathy on CXR and an ACE level of 85 U/L. Serum calcium is 11.4 mg/dL. What is the mechanism of hypercalcemia in this condition?
Answer: 1-alpha hydroxylation of vitamin D by activated macrophages in granulomas
Activated macrophages within sarcoid granulomas express 1-alpha-hydroxylase, converting 25-OH vitamin D to calcitriol, which increases intestinal calcium absorption.
A 45-year-old with idiopathic pulmonary fibrosis develops acute worsening of dyspnea over 2 weeks with new bilateral ground-glass opacities on CT superimposed on honeycombing. What is this complication called?
Answer: Acute exacerbation of IPF
Acute exacerbation of IPF is defined as rapid respiratory deterioration with new bilateral ground-glass opacities without an identifiable cause in a patient with established IPF.
A 28-year-old presents with sudden right-sided pleuritic chest pain and dyspnea after a long flight. CXR shows a 25% right-sided pneumothorax. He is hemodynamically stable with SpO2 of 96%. What is the best initial management?
Answer: Observation with supplemental oxygen and repeat CXR in 6 hours
A small-to-moderate primary spontaneous pneumothorax in a stable patient can be managed with observation and supplemental O2, which accelerates pleural air reabsorption.