Pulmonary edema and pulmonary fibrosis cause hypoxemia by which mechanism?
A) Creating alveolar dead space
B) Decreasing the oxygen in inspired gas
C) Creating a right-to-left shunt
D) Impairing alveolocapillary membrane diffusion

Question

Quizplus · Accepted Answer

Diffusion of oxygen through the alveolocapillary membrane is impaired if the alveolocapillary membrane is thickened or if the surface area available for diffusion is decreased.Abnormal thickness,as occurs with edema (tissue swelling)and fibrosis (formation of fibrous lesions),increases the time required for diffusion across the alveolocapillary membrane.None of the remaining options accurately describes the mechanism that triggers hypoxemia as a result of pulmonary edema or pulmonary fibrosis.

Pulmonary Edema and Pulmonary Fibrosis Cause Hypoxemia by Which Mechanism