Pleural disorders are conditions that affect the tissue that covers the outside of the lungs and lines the inside of your chest cavity.
The tissue is called the pleura, and the thin space between its two layers is called the pleural space. A small amount of fluid fills the pleural space, and when you breathe in and out, this fluid helps the pleural layers glide smoothly against each other. An injury, inflammation, or infection can cause the blood or air to build up in the pleural space and lead to a pleural disorder.
There are three types of pleural disorders — pleurisy, pleural effusion, and pneumothorax — and they have varying causes. Pleurisy is inflammation of the pleura. Pleural effusion and pneumothorax occur when an infection, medical condition, or chest injury causes fluid, pus, blood, air, or other gases to build up in the pleural space.
Chest pain, shortness of breath, and coughing are common symptoms of all types of pleural disorders, but treatment for pleural disorders varies depending on what type you have and how serious it is. If left untreated, pleural disorders can lead to serious problems, including complete collapse of the lung, shock, or sepsis.
Pleurisy, Pleural Effusion, and Pneumothorax
What is pleural effusion?
Pleural effusion is a buildup of fluid in the pleural space. The cause of the buildup determines the type of pleural effusion.
- Exudative effusion is caused by a buildup of fluid from inflammation, tumors, infection, or lung injury. The types of exudative effusion vary by the fluid buildup in the pleural space. For example, an empyema is a buildup of infection or pus, a hemothorax happens when blood builds up, and a chylothorax results from a buildup of chyle, a substance formed in the small intestine.
- Transudative pleural effusion is caused by pressure in the blood vessels, most often because of a medical condition such as heart, kidney, or liver failure. The pressure pushes excess fluid into the pleural cavity.
What is pleurisy?
Pleurisy is inflammation of the pleura. It is also called pleuritis.
What is pneumothorax?
A pneumothorax is a collection of air or gas in the pleural space. The buildup of air or gas can put pressure on the lung and cause all or part of it to collapse.
There are different types of pneumothorax.
- Spontaneous pneumothorax can happen suddenly and without any known cause or in people without any signs of lung disease. Sometimes, it may be caused by another medical condition that affects the lungs, such as chronic obstructive pulmonary disease (COPD).
- Tension pneumothorax is a very large pneumothorax that may result in failure of the heart and the lungs. This can interfere with blood flow through your chest and cause your blood pressure to drop.
- Traumatic pneumothorax is caused by a chest injury.
What causes pleural disorders?
Pleural disorders may be caused by one of the following.
- Inflammation in the pleura: The inflammation may happen because of an infection, tumor, or another medical condition. The inflammation affects the two thin layers of the pleura. This can cause the surface of the layers to become rough and the fluid in between the layers to become sticky. When this happens, the two layers may rub together every time you breathe in instead of gliding past each other.
- Injury to the chest: Even an injury that does not break the skin but causes internal damage, can allow air, fluid, or blood to leak into the pleural space. This can cause a pneumothorax or pleural effusion.
- Procedure such as chest biopsy, mechanical ventilation, or thoracentesis: This can cause blood or air to leak into the pleural space.
- Fluid imbalance: Pleural effusions develop when fluid enters the pleural space faster or at a higher amount than the body can reabsorb. This imbalance of fluids can be caused by heart, kidney, or liver failure, or other medical conditions.
Who is at risk?
Your risk for pleural disorders may be higher based on some factors you can control and some, like your age, that you can’t control.
- Age: Pleural disorders can happen at any age, but pneumothorax is most common in people 15 to 34 years old and people over age 55.
- Family history: If someone in your family had spontaneous pneumothorax, your risk of having this disease is higher.
- Lifestyle habits: Smoking tobacco or marijuana raise your risk of spontaneous pneumothorax.
- Medical history: The medicines you take may raise your risk, including blood thinners, cancer medicines, and nitrofurantoin, an antibiotic to treat urinary tract infections. Some health conditions may also raise the risk for pleural disorders, such as cancer, heart failure, autoimmune diseases, kidney disease, lung disease, and sickle cell disease.
- Sex: Men, especially those who are taller than average, are more likely than women to have a spontaneous pneumothorax, often without underlying lung disease.
Pleural disorders may occur with no symptoms, or they may have obvious symptoms. Symptoms and complications vary depending on the pleural disorder and how severe it is.
Symptoms for pleural disorders may include:
- Chest pain that is sharp or stabbing and gets worse when you breathe in deeply or cough or sneeze
- Shortness of breath
- Low weight or slow rate of weight gain in children: Usually the weight is well below the child’s ideal weight or the average weight of other children of the same age.
- Bluish skin caused by not getting enough oxygen
- Rapid heart rate
As part of a physical examination, your provider will measure your blood pressure and heart rate, feel your chest and belly, take your temperature, listen to your heart and lungs, and feel your pulse. They may also check the level of oxygen in your blood with a probe on your finger or forehead.
Your provider will listen to your breathing to find out whether your lungs are making any abnormal sounds.
- If you have pleurisy, the inflamed layers of the pleura may make a rough, scratchy sound as they rub against each other when you breathe. Doctors call this a pleural friction rub.
- If you have a pleural effusion, fluid buildup in the pleural space may prevent a friction rub. But if you have a lot of fluid, your provider may hear a dull sound when they tap on your chest.
- If you have a pneumothorax, your provider may hear more echo than usual when they tap on your chest.
Diagnostic tests and procedures
Your provider may order a combination of the following tests to help diagnose a pleural disorder. These tests may also help rule out other medical conditions that can cause chest pain.
- Biopsies take a sample of the pleura. The sample is checked for signs of disease.
- Blood tests show whether you have an illness that increases your risk of pleurisy or another pleural disorder
- Lung imaging tests such as a chest MRI or chest X-ray look for fluid or air in the pleural space or other possible causes of pleural disorders, such as pneumonia, a fractured rib, or a lung tumor.
- Endoscopies look for signs of disease, guide the doctor while performing a biopsy, or remove pleural fluid.
- Thoracentesis procedure removes a sample of pleural fluid for testing. The fluid removed during thoracentesis is tested and examined under a microscope for signs of infection, cancer, or other conditions that can cause fluid or blood to build up in the pleural space.
- Ultrasounds look for fluid, air, or other abnormal findings in your chest.
How your pleural disorder is treated depends on what type of pleural disorder you have and how severe it is. Some pleural disorders go away without treatment. Others will require a procedure to remove air, fluid, or other material from the pleural space. The goal of treatment is to relieve symptoms and treat the underlying condition.
Your healthcare provider may recommend medicine to treat symptoms or causes of your pleural disorder.
- Antibiotics, antifungals, or antiparasitic medicines treat infections in the pleural space or in the lung.
- Corticosteroids reduce inflammation. Corticosteroids can have serious side effects with long-term use.
- Morphine in low doses is used to treat chronic (long-term) shortness of breath. This medicine has a risk of addiction.
- Nonsteroidal anti-inflammatory drugs such as ibuprofen help reduce pain and inflammation.
Your doctor may perform one or more procedures to treat a pleural disorder. Many of these procedures are performed using ultrasound.
- Chest tubes drain fluid, blood, or air from the pleural space. This process can take several days. You may stay in the hospital while the tube is in place.
- Heimlich valves prevent fluid and air from getting into the chest when you breathe in. Your doctor may attach this one-way valve to a chest tube or indwelling pleural catheter (IPC), which allows you to move around more and may allow you to go home to wait for your lung to re-expand.
- IPC, or indwelling pleural catheters, are used to drain pleural fluid. An IPC is a semi-permanent thin tube that is left in place so patients or caregivers can drain the fluid, usually a few times a week.
- Injection of medicines into the pleural space may be needed to break up material that cannot be removed with a needle or drained through a chest tube.
- One-way endobronchial valve may be implanted in one of your bronchial tubes to allow air to exit the pleural space but not reenter.
- Pleurodesis is a procedure that can help close the pleural space by helping the two sides of the pleura stick together. For this procedure, your doctor will drain the fluid out of your chest through a chest tube. Then they will push a substance through the chest tube into the pleural space. The substance will irritate the surface of the pleura and cause the two layers of the pleura to stick together, preventing more fluid from building up.
- Surgery may be needed to remove fluid, pus, or blood clots that cannot be removed with a chest tube. You may also need surgery to remove part of the pleura, to remove one or more ribs; or to close the pleural space with a pleurodesis procedure.
- Thoracentesis is a procedure to remove air, blood, or other fluid from the pleural space with a needle. Possible complications include pneumothorax, pain, hemothorax and other bleeding, infection, and pulmonary edema. Complications are less likely if ultrasound is used to guide the procedure.
What happens if pleural disorders are left untreated?
If left untreated, or if they do not respond well to treatment, pleural disorders can lead to serious health problems. Some of the possible complications include:
- Atelectasis, a partial or complete collapse of the lung, which can be a complication of pneumothorax
- Empyema, which is pus in the pleural space
- Shock, which is a life-threatening complication of hemothorax or tension pneumothorax that can happen when blood pressure drops dangerously low
- Unexpandable (trapped or entrapped) lung, which can be a complication of pleural effusion that is caused by cancer, hemothorax, or pleurisy