This cavity is called the pleural cavity.
Typically, the pleural cavity contains a small amount of fluid that functions as a lubricant.
Large amounts of fluid or more distressing symptoms may require more aggressive treatment.

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Medications
Pleural effusion due to congestive heart failure is often treated with medication, includingdiuretics.
Pleural effusions due to infections such as pneumonia are often treated using antibiotics.
The healthcare provider inserts a needle between the ribs and drains the excess fluid.
Small incisions are made in the chest, and a tube is inserted to drain off the pleural fluid.
Alternatively, mechanical pleurodesis is performed either through video-assisted thoracoscopic surgery (VATS) or thoracoscopy.
Chest tubes come in different sizes, they can be inserted under general or local anesthesia.
The chest tube stays in place for a few days after the surgery.
In many cases, pleural effusion can be cured.
Early treatment before respiratory symptoms progress may increase your chance of curing a pleural effusion in many cases.
Summary
Pleural effusion is excess fluid in the space surrounding the lungs.
Common causes of pleural effusions include congestive heart failure, cancer, pulmonary embolism, and lung infections.
Symptoms range in severity and include difficulty breathing.
Pleural effusions are typically diagnosed based on symptoms, medical history, and medical imaging such as X-rays.
Treatments are tailored depending on the severity of symptoms and the underlying cause of the pleural effusion.
Treatment may involve the use of medications, surgical intervention, or a combination of both.
Some cases of pleural effusion can be cured, while other cases may be more complicated and quite serious.
Consult a qualified healthcare professional for any symptoms of pleural effusion.
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