Pleural Effusion (Fluid Build-Up in the Chest)

Pleural effusion is an abnormal buildup of fluid in the chest cavity, specifically in the pleural space, which is located between the layers of membrane that cover the lungs and the chest wall. There are many causes for pleural effusion, including infections, injuries, heart or liver failure, blood clots in the lungs (pulmonary emboli), and drugs. Lung cancer tumors can also cause pleural effusion, which when caused specifically by cancer is known as malignant pleural effusion.¹

Two types of pleural effusion

There are two types of pleural effusion: transudative pleural effusion, which is most often caused by heart failure, and exudative effusion, which is caused by blocked blood vessels or lymph vessels, inflammation, injury, or tumors. Transudate fluid is watery, while exudate fluid is rich in protein. Lung cancer can cause exudative effusion.^1,2

Symptoms of pleural effusion

Many people can experience pleural effusion without symptoms. However, in some patients, symptoms of pleural effusion may include:

• Chest pain, especially sharp pain that is worse with deep breathing or coughing
• Dry, nonproductive cough (does not produce mucus)
• Shortness of breath, or difficult, labored breathing
• Inability to breathe easily unless sitting up or standing
• Rapid breathing
• Fever
• Hiccups ^2,3

Diagnosis of pleural effusion

The diagnosis of pleural effusion is made using imaging, such as chest x-ray, CT (computed tomography) scan, or ultrasound. Blood tests may be done to assess kidney and liver function, and a sample of the fluid may be taken through thoracentesis, in which a needle is inserted between two ribs to remove a small amount of the fluid from the pleural space. The fluid is then examined under a microscope. In cases in which pleural effusion cannot be diagnosed by one of these less invasive techniques, doctors may perform a thoracoscopy, in which the doctor inserts a viewing tube (scope) into the chest cavity. This is done under general anesthesia (to keep the patient asleep and pain free) and may be combined with treatment.^1-3

Treatment of pleural effusion

The goals of treatment for pleural effusion are to remove the fluid, prevent the fluid from building up again, and determine and treat the cause of the fluid build-up. Treatment of pleural effusion may include the use of diuretics – medications that increase the excretion (removal) of water from the body – and/or the insertion of a chest tube to drain the fluid. The chest tube may be left in place for several days or longer.^2,3

Pleural effusion caused by lung cancer may be difficult to treat as the fluid build-up returns. Chest tubes may be kept in place to drain fluid periodically. Treating the cancer is also critical to treating the pleural effusion. Treatment may include chemotherapy, radiation therapy, surgery, or putting medication into the chest that prevents fluid build-up. The medications that are used in pleural effusion treatment are called sclerosing agents, and they intentionally cause scarring in the pleural space, which can help prevent recurrences.^1,3

Surgery for pleural effusion

When drainage or scleroising medications are not sufficient to treat pleural effusion caused by lung cancer, surgery may be performed. One type of surgery is video-assisted thoracoscopic surgery (VATS) and is minimally invasive. Small incisions are made in the chest, and fluid and any damaged tissue is removed. Sclerosing agents may be administered during the surgery to seal the layers of the pleura.^1,3