A physician is trying to determine the best index of oxygenation for a patient undergoing mechanical ventilation who has required frequent changes in FIO₂.Which of the following available indices of oxygenation should be recommended for this patient?

Question

Quizplus · Accepted Answer

The PaO₂/PAO₂ index (a-A ratio) represents the percentage of the alveolar oxygen that is trAnswerferred to the arterial blood. In theory, the percentage of the PAO2 transferred across the lung stays constant as long as lung function (whether normal or abnormal) stays constant. Thus PaO₂/PAO₂ is more stable than P(A-a)O₂ when FIO₂ changes.

A Physician Is Trying to Determine the Best Index of Oxygenation