What does the V/Q ratio represent in respiratory physiology?

The V/Q ratio represents the relationship between ventilation (V) and perfusion (Q) in the lungs, signifying how well air (ventilation) reaches the alveoli and how well blood (perfusion) reaches the alveoli for gas exchange. It is a crucial measurement in respiratory physiology because an ideal balance between ventilation and perfusion is necessary for efficient gas exchange. A perfectly matched V/Q ratio is vital for optimal oxygenation and removal of carbon dioxide from the bloodstream.

When the V/Q ratio is disrupted, either due to ventilation problems (e.g., blocked airways leading to low ventilation) or perfusion issues (e.g., blocked blood vessels leading to low perfusion), it can result in various respiratory conditions and impaired gas exchange efficiency. Therefore, understanding the V/Q ratio allows healthcare professionals to assess and manage patients with respiratory issues, ensuring appropriate interventions are made to restore balance.