Pleural effusion in older adults: fluid around the lung, causes and drainage

Macmillan explains that the lungs are covered by a lining called the pleura with two layers, the visceral pleura on the lungs and the parietal pleura lining the ribcage and diaphragm. Between them is a small amount of lubricating fluid that lets the lungs move smoothly. Sometimes too much fluid builds up between the layers; this is a pleural effusion. Kingston and Richmond adds that an effusion can occur around one lung or both, and that a large one can put pressure on the lung, causing breathing difficulty, cough and sometimes pain.

Macmillan lists breathlessness, a cough and chest pain. It says the fluid presses on the lung, making it difficult to expand fully, and that in some situations part or all of the lung can collapse. Breathlessness is easily put down to ageing, heart disease or a chest infection, so an effusion may be found only when a chest X-ray is done for breathlessness, cough or after pneumonia. Gradually worsening breathlessness should be reviewed by a GP.

If breathing is severe, with gasping, blue lips or inability to speak, call 999. For breathlessness that is new or worsening with fever or chest pain, contact the GP or NHS 111 promptly.

Kingston and Richmond says unilateral effusions are commonly caused by a problem within the lung itself, such as infection, inflammation or cancer, whereas bilateral effusions are commonly caused when the heart, liver or kidneys are not working normally, and bilateral effusions often improve with treatment of the underlying cause. Macmillan says effusions are often caused by lung infections such as pneumonia and by heart failure, and can also be a symptom of several types of cancer, for example lung cancer, breast cancer, ovarian cancer, lymphomas and mesothelioma, where cancer cells spread into the pleura and cause irritation and fluid.

For older people with known heart failure, kidney disease or liver disease, an effusion may reflect worsening of that condition, and the first step may be adjusting treatment for it. Our guides to heart failure and pneumonia cover these causes.

Macmillan says you may have a chest X-ray or an ultrasound scan, or both, and sometimes other tests to confirm the diagnosis and the cause. Kingston and Richmond explains that pleural aspiration and drainage are done to diagnose a problem: aspiration allows a small amount of fluid (20 to 100mls) to be sent for tests to help work out the cause and whether fluid is likely to return, while drainage also sends fluid for tests and allows up to 1500mls to be removed to improve breathing. Ultrasound is used to locate the fluid and mark a safe site.

Kingston and Richmond says for an aspiration local anaesthetic numbs the skin and a small needle removes a sample, often taking about 30 minutes; for drainage a small plastic tube is passed into the chest and connected to a drainage bag, usually taking about 45 minutes, then the tube is removed and a dressing applied. Most people feel well enough to resume usual activities by the next day, a simple painkiller such as paracetamol is safe unless advised otherwise, and results may take several days. Macmillan adds that the drain is often put in by a doctor or a specially trained nurse, is sometimes ultrasound-guided, may be left in place with a stitch while fluid drains, and that many hospitals offer it as a day patient procedure although some people stay about 2 days or longer.

Macmillan explains fluid is usually drained slowly because a sudden release of pressure in the chest can cause blood pressure to drop; about 1 litre may be drained safely as soon as the drain is in, and after that it must be slower. Tell the team if you feel dizzy, sick or light-headed. A bag or bottle must not be raised above chest level. In frail older people, the team monitors blood pressure and breathing closely during drainage.

Kingston and Richmond lists the risks as bleeding (low risk of serious bleeding), infection, air entering the pleural cavity (pneumothorax; a small amount may need a repeat X-ray 1 to 2 days later, a large amount may need a chest tube), a small risk of injury to the lung or other organs, and pain from the local anaesthetic lasting less than a minute. Macmillan lists a blocked drain, an infected drain and pneumothorax. Kingston and Richmond says a blood test is needed to check clotting, and that medicines such as aspirin, clopidogrel, heparin, apixaban, rivaroxaban, dabigatran and warfarin may need to be stopped beforehand; tell the doctor as soon as possible and never stop them without being told. If you feel unwell or breathing worsens afterwards, return to the Medical Day Unit or A&E as instructed.

Macmillan says if fluid builds up again you may need repeated drainage, or treatment for the cause, such as chemotherapy or hormonal therapy for cancer-related effusions. It describes a tunnelled indwelling pleural catheter (TIPC), which allows fluid to be drained into a bottle at home by the person, a family member or a community nurse, inserted on a day ward. It also describes talc pleurodesis, in which sterile talc is introduced through the drain after the lung has re-expanded so the two layers of pleura stick together, with the drain usually left in for another 24 hours; chest pain for a day or so and flu-like shivers can follow. Thoracoscopy, a camera procedure taking about 40 to 60 minutes, can drain fluid, take a biopsy and do pleurodesis at the same time. People go home 2 to 5 days after, or sometimes the same day.

Kingston and Richmond notes that if aspiration is declined the effusion can be monitored by X-ray and CT, but the cause may remain unknown, and a keyhole procedure may be recommended instead. Which option is best depends on the cause, how quickly fluid returns, general health and the person's wishes.