ABSTRACT
The pleural cavity is the potential space between the two pleurae (visceral and parietal) of the lungs. The pleurae are serous membranes which fold back onto themselves to form a two-layered membranous structure. The thin space between the two pleural layers is known as the pleural cavity and normally contains a small amount of pleural fluid. There are two layers; the outer pleura (parietal pleura) is attached to the chest wall and the inner pleura (visceral pleura) covers the lungs and adjoining structures, via blood vessels, bronchi and nerves. The parietal pleurae are highly sensitive to pain, while the visceral pleura are not, due to its lack of sensory innervation. In the current review we will present the anatomy of the pleural space.
ABSTRACT
The pleural cavity is created between the 4(th) and 7(th) week of embryologic development. These embryonic components of visceral and parietal pleurae develop different anatomic characteristics with regard to vascular, lymphatic, and nervous supply. There are two layers: a superficial mesothelial cell layer facing the pleural space and an underlying connective tissue layer. The pleura might present inflammatory response and maintenance of the pleural fluid is observed. The latter function is especially important in the mechanical coupling of the lung and chest wall. Fluid is filtered into the pleural space according to the net hydrostatic oncotic pressure gradient. It flows downward along a vertical pressure gradient, presumably determined by hydrostatic pressure and resistance to viscous flow. There also may be a net movement of fluid from the costal pleura to the mediastinal and interlobar regions. In these areas, pleural fluid is resorbed primarily through lymphatic stomata on the parietal pleural surface. In the current review we will present the physiology of the pleural space in a step by step manner.
