Alveolaarõhk

Alveolaarõhk refers to the air present within the alveoli of the lungs. The alveoli are tiny, thin-walled air sacs where the vital exchange of oxygen and carbon dioxide takes place between the lungs and the bloodstream. This air is crucial for respiration, as it represents the final compartment of the respiratory tract where gases are transferred.

The composition of alveolar air differs from that of inhaled atmospheric air. Due to continuous uptake of oxygen by the blood and release of carbon dioxide into the alveoli, the partial pressure of oxygen in alveolar air is lower than in the atmosphere, while the partial pressure of carbon dioxide is higher. This gradient is essential for driving diffusion. Specifically, the partial pressure of oxygen in alveolar air is approximately 104 mmHg, while the partial pressure of carbon dioxide is around 40 mmHg.

The continuous ventilation of the lungs ensures that alveolar air is regularly refreshed with incoming atmospheric air, maintaining these partial pressure differences. Factors such as breathing rate, tidal volume, and any airway obstruction can affect the composition and volume of alveolar air, consequently impacting gas exchange efficiency. Understanding alveolar air is fundamental to comprehending respiratory physiology and various lung conditions.