What complication can arise from a collection of air in the pleural cavity?

The presence of air in the pleural cavity is medically referred to as a pneumothorax. This condition occurs when air leaks into the space between the lung and chest wall, leading to pressure changes that can cause the lung to collapse partially or completely. When the pleural cavity fills with air, it disrupts the normal negative pressure needed to allow the lungs to expand properly during breathing. This can result in significant respiratory distress, diminished oxygen exchange, and potential respiratory failure if not addressed.

In contrast, while complications such as atelectasis (which refers to the collapse of lung tissue) and hypoxemia (a condition of low blood oxygen levels) can indeed be consequences of a pneumothorax, they are secondary effects resulting from the primary issue of air collection in the pleural cavity. Oxygen depletion, while a possible consequence, does not directly describe the condition itself. Therefore, the most appropriate and direct complication arising from the presence of air in the pleural cavity is pneumothorax.