The lungs are covered by a membrane lining called the ‘pleura’ which has an inner and outer layer in which fluid produced acts as a lubricant to enable the lungs to move efficiently without friction during breathing. In healthy lungs the pleura produces a small amount of liquid but situations can arise when the amount of fluid becomes excessive which creates pressure upon the lungs causing breathlessness, chest pain and a cough.
People experiencing a pleural effusion must seek immediate medical attention as it is potentially life threatening if left untreated.
There are numerous causes of a pleural effusion which is commonly caused by a lung infection such as pneumonia or heart failure when blood is not properly pumped throughout the body.
An effusion might also indicate cancer where cancer cells have spread within the pleura causing irritation and the build up of fluid. Typical cancers caused in this manner include two potentially asbestos-related conditions, lung cancer and mesothelioma. Other cancers include breast cancer, ovarian cancer and lymphomas.
A pleural effusion is generally a complication of another illness and therefore the risk factors which increase your chance of developing a pleural effusion are related to any one of several conditions. In the context of a former worker with asbestos exposure, a pleural effusion is always viewed with some initial concern given that asbestos exposure in itself can lead to serious lung diseases including mesothelioma which commonly presents alongside a pleural effusion.
Early symptoms of pleural mesothelioma often include pleural effusions (fluid build-up) around the lungs which can be confused with pneumonia meaning a patient may be misdiagnosed and subjected to delay in their treatment.
Other common symptoms between the two conditions include shortness of breath, chest pain, dry cough and weight loss making it more likely to consider pneumonia rather than mesothelioma. Pleural thickening (scarring) of the lung linings and pleura can also be found in both conditions and in cases involving empyema, pleurisy and tuberculosis (TB).
In suspected pneumonia cases fluid drained from the lungs is commonly tested to determine the presence of viral or bacterial pneumonia and seldom to test for mesothelioma, which is normally diagnosed by CT scan and PET Scan.
Sadly, it is not uncommon for pleural mesothelioma to be misdiagnosed (or even overlooked) given its resemblance to that of pneumonia and flu. In cases of mesothelioma early detection is vital to improve survival rates and it is important to mention any asbestos exposure at the time of examination.
Industrial settings where asbestos use was commonplace include;
Initially during physical examination your GP will listen to your lungs using a stethoscope and further tapping on the chest can also help to detect any signs of fluid.
Other diagnostic investigations include,
A pleural effusion is normally found as shadowing in the lung and is often confirmed by further investigation, CT Scan. An x-ray will detect abnormalities in the structure of the lung associated to asbestos exposure and might also confirm the existence of another asbestos scarring condition known as pleural plaques which represents less extensive scarring (focal scarring) also caused by inhalation of asbestos fibres.
CT Scan (computerised tomography)
This is a painless process which produces more detailed 3D images of the lungs and can help identify less obvious abnormalities missed by x-ray and help to determine the underlying cause of the effusion.
The treatment for an effusion depends upon the disorder in the body which is causing it to occur and aside to treating the disorder one of the first treatments involves having the fluid drained to relieve symptoms.
A pleural effusion can be drained by,
This is performed under local anaesthetic by a Doctor whereby a thin tube is normally inserted into the side of the chest through a small incision whilst the patient is sat down leaning forwards. This procedure enables the fluid to be drained slowly into a drain bag or bottle. The fluid drained is likely to be bloodstained and your blood pressure will be monitored. A small effusion might be removed by a Doctor using a small needle or thin tube (cannula) which is inserted into the chest and in some instances an ultrasound scan will be used to help guide the tube into the correct position.
If fluid continues to build-up after a chest drain it might be necessary to have a special catheter fitted which is known as a tunnelled indwelling pleural catheter (TIPC) which allows fluid to be drained through a valve into a bottle at home by the patient, a family member or nurse. This is a painless process which removes the need for repeated hospital visits, injections and chest drains.
Once the fluid has been drained and the lung re-inflated a procedure to seal the two layers of the pleura together to prevent fluid build up can be undertaken which is called a ‘pleurodesis’. This involves injection of a sterile talc mix and solution of saline into the pleural spaces via a chest drain or during video assisted thorascopic surgery (VATS) or local anaesthetic thoracoscopy (LAT). The mixture closes the linings around the lung and prevents further build-up of fluid.
Compensation for pleural effusion