Thank you for updating your details. Log In. Sign Up. Become a Gold Supporter and see no ads. Log in Sign up. Articles Cases Courses Quiz. About Recent Edits Go ad-free. Edit article. View revision history Report problem with Article. Citation, DOI and article data. Jones, J. When excess fluid accumulates between the pleural membranes, various procedures may be used to either drain the fluid or eliminate the space between the membranes.
There are two pleurae, one for each lung, and each pleura is a single membrane that folds back on itself to form two layers. The space between the membranes called the pleural cavity is filled with a thin, lubricating liquid called pleural fluid.
The visceral and parietal pleura join at the hilum, which also serves as the point of entry for the bronchus, blood vessels, and nerves. The pleural cavity, also known as the intrapleural space, contains pleural fluid secreted by the mesothelial cells. The fluid allows the layers to glide over each other as the lungs inflate and deflate during respiration.
The structure of the pleura is essential to respiration, providing the lungs with the lubrication and cushioning needed to inhale and exhale. The intrapleural space contains roughly 4 cubic centimeters ccs to 5 ccs of pleural fluid which reduces friction whenever the lungs expand or contract.
The pleura fluid itself has a slightly adhesive quality that helps draw the lungs outward during inhalation rather than slipping round in the chest cavity. In addition, pleural fluid creates surface tension that helps maintain the position of the lungs against the chest wall. The pleurae also serve as a division between other organs in the body, preventing them from interfering with lung function and vice versa.
Because the pleura is self-contained, it can help prevent the spread of infection to and from the lungs. A number of conditions can cause injury to the pleura or undermine its function.
Harm to the membranes or overload of pleural fluid can affect how you breathe and lead to adverse respiratory symptoms. Pleurisy is inflammation of the pleural membranes. It is most commonly caused by a viral infection but may also be the result of a bacterial infection or an autoimmune disease such as rheumatoid arthritis or lupus. Pleuritic inflammation causes the membrane surfaces to become rough and sticky.
Rather than sliding over each other, they membranes stick together, triggering sharp, stabbing pain with every breath, sneeze, or cough. The pain can get worse when inhaling cold air or taking a deep breath. It can also worsen during movement or shifts in position. Other symptoms include fever, chills, and loss of appetite. A pleural effusion is the accumulation of excess fluid in the pleural space. When this happens, breathing can be impaired, sometimes significantly.
Congestive heart failure is the most common cause of a pleural effusion, but there is a multitude of other causes, including lung trauma or lung cancer in which effusion is experienced in roughly half of all cases.
A pleural effusion can be very small detectable only by a chest X-ray or CT scan or be large and contain several pints of fluid. The inferior portion is then further divided into the anterior, middle, and posterior portions. Each region of the mediastinum contains specific groups of structures. The pleural cavity is a space between the visceral and parietal pleura. The space contains a tiny amount of serous fluid, which has two key functions.
The serous fluid continuously lubricates the pleural surface and makes it easy for them to slide over each other during lung inflation and deflation. The serous fluid also generates surface tension, which pulls the visceral and parietal pleura adjacent to each other. This function will allow the thoracic cavity to expand during inspiration. NB; when air enters the pleural space, the surface tension will disappear, and the resulting condition is known as a pneumothorax.
Located posteriorly and anteriorly are spaces where the pleural cavity is not totally filled by the lung parenchyma.
This space is known as the recess - an area where the adjacent surfaces of the parietal pleura come into contact. The two recesses in the pleural cavity include the following:. The reason these recesses are important is that they provide a space for fluid to accumulate. Pleural effusions usually collect in the costodiaphragmatic recess. The visceral pleura receives its blood supply from the bronchial circulation, while the parietal pleura receives its blood supply from the intercostal arteries.
The costal and cervical portions of the parietal pleura are innervated by the intercostal nerve, and the diaphragmatic portion is supplied by the phrenic nerve. The parietal pleura is the only portion of the pleura that can sense pain. The visceral pleura receives its nerve supply via the autonomic nervous system ANS and lacks sensory innervation.
Pneumothorax is a common clinical event, and it occurs when the pleural space is violated. The pleural cavities are closed sacs enveloping each lung.
Each cavity comprises a visceral layer green and a parietal layer blue.
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