The pleural cavity, pleural space, or intrapleural space is the potential space between the pleurae of the pleural sac that surrounds each lung. A small amount of serous pleural fluid is maintained in the pleural cavity to enable lubrication between the membranes, and also to create a pressure gradient.
A pleural effusion is accumulation of excessive fluid in the pleural space, the potential space that surrounds each lung. Under normal conditions, pleural fluid is secreted by the parietal pleural capillaries at a rate of 0.6 millilitre per kilogram weight per hour, and is cleared by lymphatic absorption leaving behind only 5–15 millilitres of fluid, which helps to maintain a functional vacuum between the parietal and visceral pleurae. Excess fluid within the pleural space can impair inspiration by upsetting the functional vacuum and hydrostatically increasing the resistance against lung expansion, resulting in a fully or partially collapsed lung.
Mallory–Weiss syndrome is a condition where high intra-abdominal pressures causes laceration and bleeding of the mucosa called Mallory-Weiss tears. Additionally, Mallory–Weiss syndrome is one of the most common causes of acute upper gastrointestinal bleeding, counting of around 1-15% of all cases in adults and less than 5% in children. It has been found that tears are up to 2 to 4 times more prevalent in men than women. The tears can cause upper gastrointestinal bleeding and predominantly occur where the esophagus meets the stomach. However, the tears can happen anywhere from the middle of the esophagus to the cardia of the stomach. Mallory–Weiss syndrome is often caused by constant vomiting and retching from alcoholism or bulimia. Gastroesophageal reflux disease (GERD) is another risk factor that is often linked with Mallory–Weiss syndrome. However, not every individual with Mallory–Weiss syndrome will have these risk factors. Individuals with Mallory–Weiss syndrome will have hematemesis, however the symptoms can vary.
Pleurodesis is a medical procedure in which part of the pleural space is artificially obliterated. It involves the adhesion of the visceral and the costal pleura. The mediastinal pleura is spared.
The mediastinum is the central compartment of the thoracic cavity. Surrounded by loose connective tissue, it is a region that contains vital organs and structures within the thorax, namely the heart and its vessels, the esophagus, the trachea, the vagus, phrenic and cardiac nerves, the thoracic duct, the thymus and the lymph nodes of the central chest.
A hemothorax is an accumulation of blood within the pleural cavity. The symptoms of a hemothorax may include chest pain and difficulty breathing, while the clinical signs may include reduced breath sounds on the affected side and a rapid heart rate. Hemothoraces are usually caused by an injury, but they may occur spontaneously due to cancer invading the pleural cavity, as a result of a blood clotting disorder, as an unusual manifestation of endometriosis, in response to pneumothorax, or rarely in association with other conditions.
A chylothorax is an abnormal accumulation of chyle, a type of lipid-rich lymph, in the pleural space surrounding the lung. The lymphatic vessels of the digestive system normally return lipids absorbed from the small bowel via the thoracic duct, which ascends behind the esophagus to drain into the left brachiocephalic vein. If normal thoracic duct drainage is disrupted, either due to obstruction or rupture, chyle can leak and accumulate within the negative-pressured pleural space. In people on a normal diet, this fluid collection can sometimes be identified by its turbid, milky white appearance, since chyle contains emulsified triglycerides.
Thoracentesis, also known as thoracocentesis, pleural tap, needle thoracostomy, or needle decompression, is an invasive medical procedure to remove fluid or air from the pleural space for diagnostic or therapeutic purposes. A cannula, or hollow needle, is carefully introduced into the thorax, generally after administration of local anesthesia. The procedure was first performed by Morrill Wyman in 1850 and then described by Henry Ingersoll Bowditch in 1852.
A pancreatic fistula is an abnormal communication between the pancreas and other organs due to leakage of pancreatic secretions from damaged pancreatic ducts. An external pancreatic fistula is one that communicates with the skin, and is also known as a pancreaticocutaneous fistula, whereas an internal pancreatic fistula communicates with other internal organs or spaces. Pancreatic fistulas can be caused by pancreatic disease, trauma, or surgery.
Pneumoperitoneum is pneumatosis in the peritoneal cavity, a potential space within the abdominal cavity. The most common cause is a perforated abdominal organ, generally from a perforated peptic ulcer, although any part of the bowel may perforate from a benign ulcer, tumor or abdominal trauma. A perforated appendix seldom causes a pneumoperitoneum.
Mediastinitis is inflammation of the tissues in the mid-chest, or mediastinum. It can be either acute or chronic. It is thought to be due to four different etiologies:
Pneumomediastinum is pneumatosis in the mediastinum, the central part of the chest cavity. First described in 1819 by René Laennec, the condition can result from physical trauma or other situations that lead to air escaping from the lungs, airways, or bowel into the chest cavity. In underwater divers it is usually the result of pulmonary barotrauma.
Hamman's syndrome, also known as Macklin's syndrome, is a syndrome of spontaneous subcutaneous emphysema and pneumomediastinum, sometimes associated with pain and, less commonly, dyspnea, dysphonia, and a low-grade fever.
A mediastinal tumor is a tumor in the mediastinum, the cavity that separates the lungs from the rest of the chest. It contains the heart, esophagus, trachea, thymus, and aorta. The most common mediastinal masses are thymoma, usually found in the anterior mediastinum, followed by neurogenic Timor (15–20%) located in the anterior mediastinum. Lung cancer typically spreads to the lymph nodes in the mediastinum.
Subcutaneous emphysema occurs when gas or air accumulates and seeps under the skin, where normally no gas should be present. Subcutaneous refers to the subcutaneous tissue, and emphysema refers to trapped air pockets. Since the air generally comes from the chest cavity, subcutaneous emphysema usually occurs around the upper torso, such as on the chest, neck, face, axillae and arms, where it is able to travel with little resistance along the loose connective tissue within the superficial fascia. Subcutaneous emphysema has a characteristic crackling-feel to the touch, a sensation that has been described as similar to touching warm Rice Krispies. This sensation of air under the skin is known as subcutaneous crepitation, a form of crepitus.
Pleural disease occurs in the pleural space, which is the thin fluid-filled area in between the two pulmonary pleurae in the human body. There are several disorders and complications that can occur within the pleural area, and the surrounding tissues in the lung.
Tracheobronchial injury is damage to the tracheobronchial tree. It can result from blunt or penetrating trauma to the neck or chest, inhalation of harmful fumes or smoke, or aspiration of liquids or objects.
Norman Rupert Barrett CBE FRSA was an Australian-born British thoracic surgeon who is widely yet mistakenly remembered for describing what became known as Barrett's oesophagus.
The pleurae are the two flattened closed sacs filled with pleural fluid, each ensheathing each lung and lining their surrounding tissues, locally appearing as two opposing layers of serous membrane separating the lungs from the mediastinum, the inside surfaces of the surrounding chest walls and the diaphragm. Although wrapped onto itself resulting in an apparent double layer, each lung is surrounded by a single, continuous pleural membrane.
Mediastinal shift is an abnormal movement of the mediastinal structures toward one side of the chest cavity. A shift indicates a severe imbalance of pressures inside the chest. Mediastinal shifts are generally caused by increased lung volume, decreased lung volume, or abnormalities in the pleural space. Additionally, masses inside the mediastinum or musculoskeletal abnormalities can also lead to abnormal mediastinal arrangement. Typically, these shifts are observed on x-ray but also on computed tomography (CT) or magnetic resonance imaging (MRI). On chest x-ray, tracheal deviation, or movement of the trachea away from its midline position can be used as a sign of a shift. Other structures, like the heart, can also be used as reference points. Below are examples of pathologies that can cause a mediastinal shift and their appearance.
