If blood from an area of the lung with a high $\dot { V }$ / $\dot { Q }$ is mixed with blood perfusing an area with a low $\dot { V }$ / $\dot { Q }$ , what will be the result?

Question

Quizplus · Accepted Answer

The mixing of blood from areas with high and low ventilation/perfusion ($\dot { V }$ / $\dot { Q }$) ratios results in a partial pressure of oxygen in arterial blood (PaO2) that is lower than the average of the two areas. This is because the blood from the low $\dot { V }$ / $\dot { Q }$ area, which has a lower oxygen content, dilutes the oxygen-rich blood from the high $\dot { V }$ / $\dot { Q }$ area, leading to a decrease in the overall oxygen content of the mixed blood.

If Blood from an Area of the Lung with a High