Where is pleural fluid located in relation to the lungs?

Pleural fluid is located within the pleural cavity, which is the thin space between the two pleurae – the visceral pleura that covers the lungs and the parietal pleura that lines the chest wall. This fluid serves multiple important functions, including reducing friction between the lung surfaces during respiration, providing surface tension that keeps the lungs expanded against the chest wall, and facilitating the movement of the lungs as they inflate and deflate. Understanding the anatomical position of pleural fluid is essential in recognizing its role in respiratory mechanics and the pathophysiological conditions that can arise when there are disturbances in this fluid, such as pleural effusion.