Which of the following values is above normal in a patient suffering from severe respiratory muscle weakness?

Correct Answer: D

Rationale: Severe respiratory muscle weakness raises arterial PCO2 (D). Normal PCO2 is 35-45 mmHg; weakness (e.g., diaphragm paralysis) cuts ventilation (Vt < 500 mL), causing CO2 retention (> 45 mmHg). Tidal volume (A) drops (~300 mL vs. 500 mL), vital capacity (C) falls (< 4 L vs. 4.8 L) due to weak inspiratory force, and oxyhemoglobin saturation (B) decreases (< 95%) from hypoventilation. D's elevation unlike A's or C's reduction stems from inadequate alveolar ventilation (Va = (Vt - Vd) × RR), pushing PCO2 up as O2 drops (Q15), per gas exchange physiology.

Correct Answer: C

Rationale: More surface tension reduces compliance. Compliance (ΔV/ΔP, A) is ~0.2 L/cm H2O normally, highest at FRC (B). High tension (no surfactant) stiffens alveoli (Q5), lowering compliance not raising it (C). Fibrosis cuts it (D, < 0.1 L/cm H2O, Q1). Emphysema boosts it . C's reversal unlike A's definition opposes Laplace's law (P = 2T/r), per physiology.

Correct Answer: D

Rationale: Decreased FEV1 (D) fits both obstructive (e.g., COPD) and restrictive (e.g., fibrosis) diseases. Obstructive: FEV1 drops (air trapping), FVC normal/low, ratio < 70%. Restrictive: FEV1 and FVC decrease, ratio ≥ 80% (Q1). RV rises in obstructive (Q13), falls in restrictive (A, false). TLC increases in obstructive, decreases in restrictive (B, false). Vascular resistance rises in restrictive (C, false, Q10). D's universal drop unlike A's specificity aligns with spirometry, per physiology.

Correct Answer: C

Rationale: Advanced chronic obstructive emphysema (COPD) benefits most from antibiotics, mechanical respiration, and bronchodilators (C). Exacerbations often involve infection antibiotics (e.g., amoxicillin) target this. Bronchodilators (e.g., albuterol) relieve obstruction, while mechanical ventilation (e.g., BiPAP) supports failing respiration without high Oâ‚‚ risks. Continuous 100% Oâ‚‚ (A, E) suppresses hypoxic drive, worsening hypercapnia. Morphine (B) sedates, risking respiratory depression. High Oâ‚‚ ventilation (D) lacks infection focus. This triad addresses infection, airflow, and ventilatory support, optimizing outcomes in severe COPD, a balanced approach critical in ICU nursing care.

Correct Answer: D

Rationale: All (D) sulfur dioxide (A), ozone (B), carbon monoxide (C) are air pollutants. SOâ‚‚ from fossil fuels irritates airways, linked to bronchitis. Ozone, from photochemical smog, damages alveoli, worsening asthma. CO binds hemoglobin, causing hypoxia, not a direct lung irritant but systemic. Each contributes to respiratory morbidity e.g., COPD exacerbations key in environmental health nursing for patient education on exposure reduction.