ATI LPN
NCLEX PN Questions Respiratory System Questions
Question 1 of 5
Which person would be expected to have the largest PAO2-PaO2 gradient?
Correct Answer: B
Rationale: Pulmonary fibrosis (B) maximizes PAO2-PaO2 gradient. Normal PAO2 ~100 mmHg, PaO2 ~95 mmHg (gradient ~5 mmHg); exercise (A) narrows it (perfusion rises). Fibrosis thickens diffusion barrier (0.2 to 1 μm), dropping PaO2 (~60 mmHg, Q10), widening gradient (~40 mmHg). Anemia (C) lowers O2 content, not gradient. Altitude (D) cuts both PAO2 and PaO2 (~60 mmHg), gradient ~5-10 mmHg. B's diffusion limit unlike A's efficiency drives the largest gap, per physiology (Q55).
Question 2 of 5
Causes of interstitial lung disease include:
Correct Answer: D
Rationale: Interstitial lung disease (ILD) has multiple causes, making all of these' correct. Chemical/physical irritants (A) e.g., asbestos, silica trigger fibrosis via chronic inflammation. Sarcoidosis (C) forms granulomas, scarring interstitium. Alveolar proteinosis (B), though rarer, involves surfactant accumulation, impairing gas exchange, often linked to dusts or autoimmunity. Options D (A & C) omits B, but all contribute irritants via direct damage, sarcoidosis via immune response, proteinosis via alveolar dysfunction. ILD's diverse etiology, from environmental to idiopathic, reduces lung compliance and diffusion capacity, key in diagnosis (e.g., biopsy, CT), guiding therapy like steroids or lavage, a broad respiratory pathology spectrum.
Question 3 of 5
Of the following disease, the one in which a marked Leucocytosis is most likely to be found is:
Correct Answer: A
Rationale: Lobar pneumonia (A) most likely shows marked leucocytosis bacterial infection (e.g., Streptococcus pneumoniae) drives neutrophil counts high (e.g., 15,000-20,000/mm³) as an acute response. Atypical pneumonia (B viral, Mycoplasma) has normal or mild elevation. Tuberculosis (C) may show lymphocytosis, not marked leucocytosis, unless severe. Influenza (D) often depresses counts. Sarcoidosis features granulomas, not neutrophil surges. Lobar's bacterial consolidation lobar opacity on x-ray triggers this, key in differentiating from chronic or viral etiologies, guiding antibiotic therapy in respiratory nursing.
Question 4 of 5
Which of the following would one expect to find in pleural fluid associated with lung cancer:
Correct Answer: D
Rationale: Pleural fluid in lung cancer shows protein >3.5 g/100 mL (D) exudative from tumor inflammation or necrosis (Light's criteria: pleural/serum protein >0.5). Specific gravity <1.015 (A) or >1.015 (B) varies, not diagnostic alone. Protein <3.5 g (C) fits transudates (e.g., CHF). RBCs <100/mm³ underestimates cancer often yields bloody fluid (>10,000). High protein reflects malignancy's leakiness, key in thoracentesis analysis for oncology nursing.
Question 5 of 5
Microcytic anemia is not found in:
Correct Answer: B
Rationale: Microcytic anemia (small RBCs, MCV <80 fL) isn't found in pernicious anemia (B) B12 deficiency causes macrocytic anemia (MCV >100 fL) from impaired DNA synthesis. Hypothyroidism (A), malabsorption (C), and chronic infection reduce iron, yielding microcytosis. Folic acid deficiency (D) mirrors B12, macrocytic. Pernicious anemia's autoimmune gastric atrophy blocks B12 absorption, key in hematology nursing for Schilling test and B12 therapy.