Regarding intrapleural pressure, which one is true?

Correct Answer: D

Rationale: Intrapleural pressure is always less than atmospheric (D) . At rest (FRC), it's -5 cm H2O (755 mmHg vs. 760 mmHg); inspiration drops it to -7 cm H2O, aiding lung expansion. A's only inspiration' is false it's always negative. B's equality occurs in pneumothorax (Q11). C's definition fits transpulmonary pressure, not intrapleural alone. D's consistency unlike A's limit maintains lung inflation, per pleural mechanics (Q60).

Correct Answer: D

Rationale: In pulmonary fibrosis, FEV1/FVC is ≥ normal. A 10% diameter increase cuts resistance (R ∝ 1/r^4), not raises it (A, false). COPD is common (B, false). Fibrosis restricts, not obstructs (C, false resistance normal). D's ratio (> 80%) holds as FEV1 and FVC drop evenly (Q1), unlike A's physics error, per restrictive physiology.

Correct Answer: D

Rationale: Chronic emphysema, an obstructive disease, causes CO₂ retention (hypercapnia), lowering pH (acidosis) as HCO₃⁻ rises to compensate respiratory acidosis. Chloride drops (low Cl⁻) via renal compensation, shifting anions, yielding low pH, low chloride, high CO₂ content' (D). High pH (A, E) suggests alkalosis, unfit for chronic CO₂ buildup. Eosinophilia (B) ties to allergy, not emphysema. Low CO₂ (C) fits hyperventilation, not obstruction. This blood gas shift e.g., pH 7.30, PaCO₂ 60 mmHg reflects ventilatory failure, critical in monitoring COPD progression and guiding oxygen or ventilatory support in advanced stages.

Correct Answer: D

Rationale: Pickwickian syndrome (obesity hypoventilation syndrome) features obesity (A), somnolence (B), and polycythemia high RBCs from chronic hypoxia (e.g., SpOâ‚‚ <90%). Excessive appetite (C) contributes to obesity but isn't a core association weight gain drives it. Anemia (D) contradicts hypoxia's erythropoietic stimulus; polycythemia is typical. This triad obesity restricts breathing, causing COâ‚‚ retention and daytime sleepiness defines the syndrome, distinct from sleep apnea alone. Anemia's absence (D) is the exception, key in recognizing this respiratory-metabolic overlap, guiding weight loss or ventilatory support in nursing care.

Correct Answer: A

Rationale: Pleuritis pleural inflammation produces friction rub (A), a creaking sound from inflamed surfaces (e.g., pneumonia, TB). CHF (B) causes effusion, not rub. Duct rupture (C) yields chylothorax. Pseudomonas (D) links to empyema. Bleb is pneumothorax. Rub's auscultatory hallmark is key, guiding anti-inflammatory therapy in chest assessment.