If a pulmonary embolism blocks a significant portion of pulmonary blood flow, which consequence follows regarding the ventilation-perfusion ratio in the affected lung region?

💡 Explanation

A pulmonary embolism obstructs blood flow to a lung region; because ventilation remains constant while perfusion decreases, the ventilation-perfusion ratio increases, therefore, the ratio increases significantly above one, rather than remaining unchanged or oscillating, because the blood flow is severely limited.

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