What impact does initial high altitude exposure have on the alveolar-arterial oxygen difference?
A) It is increased
B) It is decreased
C) It is normal but will increase during exercise
D) It is not affected by changes in altitude

Question

Quizplus · Accepted Answer

Initial high altitude exposure leads to a decrease in alveolar oxygen tension due to the reduced partial pressure of oxygen at higher altitudes. However, oxygen diffuses across the alveolar-capillary membrane and enters the capillary blood, leading to an increase in arterial oxygen pressure. This results in an increased alveolar-arterial oxygen difference, which is the difference between the oxygen tension in the alveoli and the arterial blood. The increase in this difference is due to the reduced oxygen tension in the alveoli and the increased oxygen extraction by the tissues.

What Impact Does Initial High Altitude Exposure Have on the Alveolar-Arterial