Depends. Depends on ethiology. Provide more information about context and severity to provide specific answer.
See below. Initially, a thoracentesis is done. This allows drainage and allows the fluid to be sent for analysis. If you are in the hospital, chest tube drainage is another common option. If it is recurrent, then there are other options. These include pleurodesis, where a chemical is placed in the pleural space to make the linings of the lung stick together; Tunneled chest tube; VATS.
Collection of fluid. Plural cavity (the space around lungs) normally will have very small amount fluid for lubrication around the lungs and chest wall. When detectable amount accumulates could be due to cancer cells deposits or could be due to heart&lung diseases (non cancers).
See below. A pleural effusion is an abnormal build up of fluid in the pleural space.
Fluid. Pleural effusion is a build up of fluid around the lung, and can compress the lung & cause breathing difficulty. The fluid can occur from heart failure, infection, tumor, etc.
Fluid pleural space. The pleusa is a specialized tissue that lines the lung (visceral pleura) and the thorax (parietal pleura), every day it is estimated up to 9 liters of fluid could be exchanged in between the pleuras. This fluid traverses the pleural spaces and gets absorbed in the visceral pleuras. The process is seamless but conditions that affect the pleura or the lungs may result in fluid buildup in the space.
Ethiology. Need to determine the ethiology before I can tell you the treatment.
Determine cause. Pleural effusions, or fluid build-up around the lungs, is not normal. Pleural effusions can arise from infection, heart failure, liver failure, malignancies or trauma. The treatment will depend on the cause. Your doctor will need to run some tests and may need to sample some of the fluid to characterize it. If there is a lot of fluid and you are symptomatic, thoracentesis may be required.
Depends. What you feel depends on what is causing the effusion to begin with. An effusion may occur because of cardiac, pulmonary or pleural problems. The main symptom is varying degrees of shortness of breath. How much you are short of breath depends on how good your heart, and lung function was before it happened and the event causing the effusion.
Shortness of breath. The key symptom of a pleural effusion is shortness of breath. .. Since fluid is denser than air, and since the chest cavity is limited by the rib cage (cannot not expand much), then accummulation of pleural fluid (or effusion) will cause the lungs to be compressed. .. As more and more pleural effusion accummulates, then more lung is compressed, and shortness of breath gets worse. ..
See below. Sometimes there are no symptoms if the effusion is small or develops slowly. Other times and most often, patients are short of breath. They can also have pain due to the fluid irritating the lining of the lung - called pleurisy.