Pleural effusion is defined as an abnormal accumulation of fluid in the pleural space. The pleura produces a fluid which acts as a lubricant that helps you to breathe easily, allowing the lungs to move in and out smoothly. The most common causes are disease of the heart or lungs, and inflammation or infection of the pleura. A pleural effusion is an accumulation of fluid between the layers of the membrane that lines the lungs and chest cavity. Approximately 1 million pleural effusions are diagnosed in the United States each year. Pleural effusion itself is not a disease as much as a result of many different diseases. If blood is in the accumulating fluid, the condition is called "hemothorax"; if pus is present, it is called "empyema"; if air enters the space, it is called "pneumothorax"; and if there is chyle (milky fluid consisting of lymph and fat), it is called "chylothorax." When certain disorders occur, excessive pleural fluid may accumulate and cause pulmonary signs and symptoms. Effusions may be the presenting sign of cancer or they may develop after the cancer is diagnosed.
Parietal pleurae cover the inner surface of the thoracic cavity, including the mediastinum, diaphragm, and ribs. Any extra fluid is taken up by blood and lymph vessels, maintaining a balance. A pulmonary embolism is a blood clot that has floated through the bloodstream and lodged in the lungs. There are two types of pleural effusion: the transudate and the exudate. When either too much fluid forms or something prevents its removal, the result is an excess of pleural fluid--an effusion. Thus, there are in fact two layers of pleura between the outer surface of the lung and the chest wall. One is adherent to the lung, whereas the other layer follows the outline of the chest wall. The two layers press up against one another, and in the healthy chest, there is no air or significant fluid between them. Cancer is responsible for 40% of all pleural effusions, which are then called malignant pleural effusions. Blood in the pleural space (hemothorax) usually results from a chest injury. Rarely, a blood vessel ruptures into the pleural space when no injury has occurred, or a bulging area in the aorta (aortic aneurysm) leaks blood into the pleural space. Any significant increase in the quantity of pleural fluid is a pleural effusion.
Causes of Pleural Effusion
- Pericarditis. This is an inflammation of the pericardium, the membrane covering the heart.
- Cirrhosis (hepatic hydrothorax).
- Autoimmune disease such as systemic lupus erythematosus , bleeding (often due to chest trauma), chylothorax (most commonly caused by trauma), and accidental infusion of fluids.
- Intraabdominal abscess.
- The most common causes of transudative pleural effusions in the United States are left ventricular failure , pulmonary embolism , and cirrhosis.
- Asbestos pleural effusion.
- Atelectasis (which may be due to malignancy or pulmonary embolism).
- The most common causes of exudative pleural effusions are bacterial pneumonia , cancer (with lung cancer , breast cancer), viral infection, and pulmonary embolism .
Symptoms of Pleural Effusion
Some sign and symptoms related to Pleural Effusion are as follows:
- The key symptom of a pleural effusion is shortness of breath.
- Fever and chills, depending on the cause.
- Weight loss.
- The pain may start and remain in one specific area of the chest wall, or it may spread to the shoulder or back.
- A cough that brings up small amounts of blood.
- Night sweats.
- Rapid breathing.
- Swelling in several joints.
Treatment of Pleural Effusion
Here is list of the methods for treating Pleural Effusion:
- Rheumatic fever is treated with antibiotics (usually penicillin) to kill strep bacteria, together with aspirin or other anti-inflammatory drugs to reduce inflammation.
- Large pleural effusions, causing severe breathlessness, are drained, by needle in an acute emergency, or otherwise by chest drain inserted under local anaesthetic.
- Tube thoracostomy. A tube is inserted through the chest and into the pleural space to drain pleural fluid. When used alone, recurrence is very common.
- A small pulmonary embolism can be treated with anticoagulants, drugs that thin the blood and prevent future blood clots.
- Therapeutic thoracentesis may be done if the fluid collection is large and causing pressure or shortness of breath.
- Surgical intervention is most often required for parapneumonic effusions.