What is Ventilation/Perfusion (V/Q)?

Ventilation/Perfusion (V/Q) matching refers to the matching of ventilation (airflow) and perfusion (blood flow) in the lungs. This process is crucial for efficient gas exchange, which involves the exchange of oxygen (O2) from the air into the bloodstream and removing carbon dioxide (CO2) from the bloodstream into the air.
In the lungs, air is brought in through ventilation, and blood flows through the pulmonary capillaries, facilitating perfusion. The goal is to ensure that areas of the lung receiving ventilation also receive an adequate blood supply and vice versa. Gas exchange efficiency depends on the close coordination of these two processes. V/Q matching is essential for maintaining sufficient oxygenation and preventing hypoxemia (low oxygen levels) or hyperoxemia (high oxygen levels). Imbalances in V/Q matching can occur in conditions such as pulmonary embolism, pneumonia, and certain lung diseases, impacting respiratory function.