Pleural effusion is an abnormal build up of fluid in the space between the linings (pleura) of the lung. The pleura is a thin membrane that lines the surface of the lungs and the inside of the chest wall outside the lungs. In pleural effusions, fluid accumulates in the space between the layers of pleura. Normally, an undetectable amount of fluid is present in the pleural space, allowing the lungs to move smoothly within the chest cavity during breathing.
Pleural effusions can result from many medical conditions. They include:
- Congestive heart failure
- Liver disease
- End-stage renal disease
- Pulmonary embolism
- Systemic lupus (SLE) and other auto-immune conditions
- Infection ie Empyema
Small pleural effusions often cause no symptoms unless they are more severe or if inflammation is present. Symptoms of pleural effusions may include:
- Shortness of breath
- Chest pain, especially on breathing in deeply (pleurisy)
- Rapid breathing
Chest X-ray film: Plain X-ray films of the chest are often the first step in identifying a pleural effusion. If a pleural effusion is suspected, additional X-ray films may be taken to show if the fluid flows freely within the chest. The presence of one sided pleural effusion vs pleural effusion on both sides is also crucial in the evaluation of a patient.
Computed tomography (CT Scan) and Ultrasound: These may be required to confirm the presence of pleural effusion.
Pleural Fluid Analysis: Once a pleural effusion is identified on imaging, a fluid sample is usually taken to determine its characteristics. In a procedure called thoracentesis, the doctor inserts a needle and a catheter between the ribs, into the pleural space. A small amount of fluid is withdrawn for testing while a large amount can be removed simultaneously to relieve symptoms. Sometimes, a pleural biopsy is taken, esp when the effusion is likely to be due to tuberculosis.
Treatment for pleural effusions may often simply mean treating the underlying condition causing the fluid build-up. Examples include giving antibiotics for pneumonia or diuretics for congestive heart failure.
Pleural drain (also known as chest tube): For pleural effusions that repeatedly recur, a catheter can be inserted through the skin into the pleural space. The pleural catheter can be left for days to weeks to drain the effusion completely.