The Chest Clinic
Pleural effusion
What is a pleural effusion?
A pleural effusion is a build-up of fluid in the space between the lung and chest wall. It is a finding with several possible causes, including heart failure, infection, inflammation and cancer. Fluid around a lung does not, by itself, mean that cancer is present.
Symptoms
An effusion may cause breathlessness, cough or chest discomfort. A small collection can be found incidentally on a scan. Symptoms and the underlying cause guide how urgently investigation or drainage is needed.
Finding the cause
Assessment usually includes chest imaging and ultrasound, alongside relevant blood tests. CT may provide more detail. When a sample is needed, ultrasound helps identify a safe place to remove fluid using a needle or small tube after local anaesthetic. Laboratory tests look for infection, abnormal cells and other clues.
A fluid sample does not always give a final diagnosis. If the cause remains uncertain, an image-guided pleural biopsy or thoracoscopy may be discussed. Thoracoscopy allows the specialist to inspect the lining of the chest and take tissue samples. Your team explains the intended benefit, risks and alternatives.
Treatment
Treatment addresses the cause and, where helpful, removes fluid to ease breathlessness. A pleural infection may require antibiotics and a chest drain. Other effusions may improve when the underlying condition is treated.
If a symptomatic cancer-related effusion keeps returning, options can include pleurodesis or an indwelling pleural catheter. Pleurodesis aims to prevent fluid collecting by making the two pleural surfaces adhere. A catheter allows planned drainage at home with appropriate support. The choice depends on lung expansion, your health and preferences.
After a procedure and urgent advice
Follow your hospital’s instructions about dressings, medicines and follow-up. Tell the team about blood-thinning medicines before any procedure; do not stop them without advice.
Seek urgent advice for increasing breathlessness, fever or worsening chest pain, especially after drainage. Call 999 for severe breathing difficulty, collapse or sudden confusion. A routine appointment is not a substitute for emergency assessment.
Sources and further information
CUH: indwelling pleural catheters
BTS: pleural disease quality standard
General information for adults; investigation and treatment are individual.