What is the main cause of Acute Respiratory Distress Syndrome (ARDS)?

The primary cause of Acute Respiratory Distress Syndrome (ARDS) is fluid accumulation in the alveoli, which results from a variety of underlying conditions that damage the alveolar-capillary membrane. This condition causes increased permeability of the capillaries, leading to the infiltration of fluid into the alveoli. This fluid disrupts the gas exchange process in the lungs, significantly impairing oxygenation and leading to respiratory failure.

While infections in lung tissue can contribute to lung injury, they are often one of the triggers rather than the direct cause of ARDS itself. Abrasion of the lung lining and airway constriction do not adequately represent the pathophysiological processes that lead to ARDS. The essential feature of ARDS is indeed the accumulation of fluid in the alveoli, making it challenging for the lungs to function effectively.