Regarding physiological dead space, one of the following is wrong?

Correct Answer: D

Rationale: Physiological dead space isn't just alveolar dead space . It's anatomic (~150 mL) plus alveolar dead space (A, true). Lung disease (B) and high V/Q (C) increase it (e.g., embolism, Q34). D's equation misses anatomic part alveolar dead space varies (0 to >150 mL), while physiological sums both. Bohr's method (Q12) confirms. D's error unlike A's baseline misdefines total wasted ventilation, per physiology (Q3).

Correct Answer: D

Rationale: All (D) are true for rheumatoid lung disease. Rheumatoid arthritis (RA) raises idiopathic pulmonary fibrosis risk (A) interstitial inflammation scars lungs, a known extra-articular feature. Nodular lesions (B), akin to subcutaneous rheumatoid nodules, appear in lung parenchyma, histologically identical (necrobiotic centers). Progressive fibrosis in coal miners with RA and positive rheumatoid factor (C) Caplan's syndrome combines pneumoconiosis and RA's immune response. These manifestations, from fibrosis to nodules, reflect RA's systemic nature, complicating lung function (restrictive patterns), key in rheumatology-pulmonology overlap for diagnosis (e.g., HRCT) and management (e.g., immunosuppression).

Correct Answer: C

Rationale: Ventilation-perfusion (V/Q) inequality mismatched air and blood flow can cause both hypercapnia and hypocapnia (C). Low V/Q (e.g., pneumonia) traps COâ‚‚, raising PaCOâ‚‚ (hypercapnia). High V/Q (e.g., pulmonary embolism) over-ventilates, dropping COâ‚‚ (hypocapnia). Hypercapnia' (A) or hypocapnia' (B) alone ignores dual potential. Neither' (D) denies impact. V/Q mismatch, assessed via A-a gradient or scans, disrupts gas exchange, critical in diagnosing shunt or dead space, guiding oxygen or thrombolytic therapy in chest emergencies.

Correct Answer: C

Rationale: Chylothorax milky pleural fluid results from thoracic duct rupture (C), often traumatic or malignant, leaking lymph (high triglycerides, >110 mg/dL). Friction rub (A) is pleuritis. CHF (B) gives transudate. Pseudomonas (D) ties to empyema. Bleb causes pneumothorax. Duct injury's lymphatic spill is distinct, key in nursing for drainage or surgical consult.

Correct Answer: C

Rationale: For polycythemia (RBC 8M, Hb 18 g/dL, Hct 61%), intravenous pyelogram (C) clues diagnosis renal tumors (e.g., hypernephroma) cause secondary polycythemia via erythropoietin, no splenomegaly fits. Splenic aspirate (A) targets primary PV. Scalene biopsy (B) checks lymphoma. LE test (D) is lupus, unrelated. Bronchoscopy assesses lung. IVP screens renal etiology, key in nursing for imaging prep and erythropoietin assay.