Which of the following events are feasible explanations for the oxygen-associated hypercapnia that sometimes affects patients who have severe COPD?
I.Hypoxic stimulus removal
II.Worsening of $\dot{V} / \dot{Q}$ relationships
III.As PaO₂ increases, the slow reduction in PaCO₂induces hypoventilation.
IV.Shunt

Question

Which of the following events are feasible explanations for the oxygen-associated hypercapnia that sometimes affects patients who have severe COPD?
I.Hypoxic stimulus removal
II.Worsening of

\dot{V} / \dot{Q}

relationships
III.As PaO₂ increases, the slow reduction in PaCO₂induces hypoventilation.
IV.Shunt

Quizplus · Accepted Answer

Several investigators suggest that oxygen breathing worsens the lungs' ventilation-perfusion ( $\dot{V} / \dot{Q} $ ) relationships, creating more dead space. Other investigators have suggested that oxygen-induced hypercapnia is caused by the combined effects of $\dot{V} / \dot{Q} $ hypoxic stimulus removal and redistribution of relationships in the lungs.

Which of the Following Events Are Feasible Explanations for the Oxygen-Associated