Alveolarflüssigkeit

Alveolarflüssigkeit, also known as alveolar fluid, is a thin layer of liquid lining the inner surface of the alveoli in the lungs. These tiny air sacs are the primary sites of gas exchange in the respiratory system. The alveolar fluid plays a crucial role in facilitating the diffusion of oxygen from the inhaled air into the bloodstream and the diffusion of carbon dioxide from the blood into the air to be exhaled.

This fluid layer is composed of a complex mixture of water, ions, proteins, and surfactants. Surfactants are particularly important as they reduce the surface tension of the alveolar fluid. Without surfactants, the high surface tension would cause the alveoli to collapse during exhalation, making breathing impossible. The production and maintenance of alveolar fluid are primarily carried out by specialized cells within the alveolar walls, namely alveolar epithelial cells.

The composition and volume of alveolar fluid are tightly regulated to ensure optimal lung function. Imbalances in this fluid, such as excessive accumulation (pulmonary edema) or deficiency, can lead to significant respiratory problems. Pulmonary edema, for example, thickens the diffusion barrier between the alveoli and capillaries, impairing gas exchange and causing shortness of breath. The careful balance of alveolar fluid is therefore essential for the efficient and continuous supply of oxygen to the body's tissues.