Which factor most directly affects oxygenation in a patient with pneumonia?

Correct Answer: A

Rationale: Pneumonia causes airway inflammation and consolidation, obstructing air flow and impairing oxygenation more directly than fluid overload, heart rate, or blood pressure.

Correct Answer: A

Rationale: Tachypnea (rapid breathing) is a compensatory mechanism to increase oxygen intake in hypoxia, unlike bradycardia, hypotension, or lethargy, which suggest decompensation.

Correct Answer: C

Rationale: Chest physiotherapy mobilizes thick secretions, improving airway clearance and oxygenation, more effectively than fluids alone, oxygen, or activity restriction.

Correct Answer: C

Rationale: The Venturi mask delivers a precise fraction of inspired oxygen (FiO2) via adjustable settings, ideal for conditions like COPD, unlike nasal cannula, simple mask, or non-rebreather.

Correct Answer: A

Rationale: Pre-oxygenation increases oxygen reserves, preventing hypoxemia during suctioning, unlike prolonged suction, large catheters, or continuous suction, which can worsen hypoxia.