Fluid around the lungs — what patients often call fluid on the lungs or in the lungs — that keeps coming back is one of the most distressing problems in chest medicine. Repeated drainages relieve the breathlessness for days, the fluid re-accumulates, and there is often still no clear diagnosis. A single-incision VATS pleural biopsy at London Bridge Hospital or The Lister Hospital Chelsea does four things in one operation: drains the fluid fully (typically more than a litre), takes biopsies for a definitive diagnosis, re-expands the lung under controlled pressure, and either prevents the fluid coming back with talc pleurodesis or plans long-term control with a PleurX drain. Private appointments within 2–3 working days. Self-referrals welcome.
Last reviewed: May 2026 · Dr Lawrence Okiror FRCS(CTh) FRCSEd(CTh) · GMC 6150382
A single-incision VATS pleural biopsy drains the fluid, takes biopsies, re-expands the lung and prevents recurrence — four things at once.
Whether the lung re-expands once the fluid is removed decides between talc and PleurX — judged in theatre, not on the scan.
Controlling the fluid is often needed before chemotherapy, immunotherapy or radiotherapy can begin — and lets oncology treatment continue safely once it has.
A scan shows the fluid around the lung. It cannot show what the lung will do once the fluid is removed — and that is the question that decides what happens next. Whether the lung fully re-expands or stays trapped against the chest wall determines whether talc can stop the fluid returning, or whether a PleurX drain is the right answer for long-term control at home.
That answer comes from one operation, watched in theatre, not from a scan. Request an appointment within 2–3 working days →
The space between the lung and the chest wall — the pleural space — normally holds only a thin film of lubricating fluid. Just enough to let the lung slide as you breathe. When that balance is disrupted, fluid can accumulate from a few hundred millilitres up to a litre or more. Most patients call this fluid on the lungs or fluid in the lungs; the technical term is pleural effusion. All three describe the same problem.
Cancer is the most common cause in adults — either lung cancer, or cancers that spread to the pleural surface from elsewhere such as breast, ovary or lymphoma. Mesothelioma is a less common but important cause. Infection (including empyema), heart failure, liver disease and other conditions also produce pleural fluid.
A chest X-ray or CT scan shows the fluid clearly but cannot reliably show what is producing it. That distinction matters because the treatment of fluid caused by cancer is different from fluid caused by infection or heart failure.
Fluid alone, sent to the laboratory, identifies the underlying cause in roughly 60 per cent of cases. A tissue biopsy of the pleural surface itself raises that figure substantially — and directs the right systemic treatment.
Patients often arrive having been through the cycle several times already. The chest fills with fluid. Breathlessness becomes severe. A needle drainage in clinic or A&E removes a litre or more and the relief is immediate. Days or weeks later the fluid is back. Another drainage. The same conversation. Often still no clear answer about what is causing it.
The reason this happens is straightforward. Repeat drainage removes the fluid but does not address what is producing it. When the pleural surface itself is producing fluid — most often because cancer cells have spread to line the surface, sometimes because inflammation has thickened the pleura — the fluid will keep coming back until something is done about the surface itself.
The cycle is fixable. Two things need to happen together: a tissue diagnosis (so the underlying cause is properly identified, which then directs systemic treatment such as chemotherapy or immunotherapy), and a definitive way to stop the fluid coming back — either by gluing the lung to the chest wall (talc pleurodesis), or by managing the fluid as it forms with a tunnelled drain (a PleurX). One operation can do both at once.
VATS — video-assisted thoracoscopic surgery, often called keyhole chest surgery — is the standard surgical approach. In almost all cases the operation requires a single small incision between the ribs, through which a camera and instruments pass. The operation is performed under general anaesthetic and most patients stay one or two nights with a chest drain in place.
Typically more than a litre is removed in one operation — not the partial drainage of a needle in clinic. Full drainage is what allows the lung to attempt re-expansion.
Several biopsies are taken from the pleural surface and sent to pathology. Results typically return within a week and direct the right systemic treatment — ending the diagnostic uncertainty.
Air is delivered to the lung under controlled pressure by the anaesthetist while the surgeon watches directly. This recruits parts of the lung that have collapsed under the weight of the fluid.
If the lung fully re-expands, talc pleurodesis is performed in the same operation. If the lung is trapped, a PleurX drain is planned — sometimes inserted at the same operation.
The operation takes about an hour. Most patients spend one or two nights in hospital with a chest drain in place, which is removed before discharge. The biopsy results follow within a week and shape what comes next.
This is the single most important moment of the operation, and it cannot be made from a scan. Once the fluid is fully drained and the lung has been re-expanded under controlled pressure, there are two possible appearances.
If the lung fully re-expands to fill the chest cavity and meet the chest wall snugly along its surface, talc pleurodesis can work — talc is applied directly to the pleural surface during the same operation, while the two surfaces are in contact.
If the lung does not fully re-expand because scarring on its surface or a thickened, stiff pleura is holding it down, the lung is said to be trapped. In that situation talc has nothing to glue against. A PleurX drain is planned — sometimes inserted at the same operation, sometimes shortly afterwards.
This is why the operation matters. The choice between the two treatments depends on what the surgeon sees in theatre, not on what the scan shows. Both treatments are good treatments for the right patient — the operation lets the right one be chosen.
Talc pleurodesis works like glue. Sterile talc powder is sprayed onto the pleural surface during the VATS operation. It causes a controlled inflammation that, over the following days, sticks the lung to the chest wall along its full surface. With the two surfaces stuck together, there is no longer a space for fluid to accumulate.
But — and this is the part that matters — glue only works if the two surfaces meet. If the lung does not fully re-expand and there is a gap between the lung and the chest wall, talc will not stick the surfaces together. Fluid will simply fill the gap again. That is why the decision to perform talc pleurodesis is made in theatre, after watching how the lung behaves, not pre-decided from a scan.
After talc pleurodesis a chest drain stays in place for a short time — usually two to three days — until the drainage is minimal and the pleurodesis is established. The drain is removed before discharge.
Typically three to five days from operation to discharge after talc pleurodesis — longer than a biopsy alone, because the drain stays in until the pleurodesis is established.
A PleurX is not what is offered when talc cannot be done. It is the right answer when the lung is trapped — and frequently the better one. Removing fluid as it forms relieves the breathlessness the trapped lung is causing, without needing to glue surfaces that cannot meet.
Trapped lung is best pictured as a partially inflated balloon with tape stuck on it. Once the air comes out, the tape stops it inflating snugly inside its box. The lung is held down by scarring on its surface or by a thickened, stiff pleura, and it cannot re-expand to fill the chest cavity. A gap remains between the lung and the chest wall, and that gap fills with fluid. The fluid puts pressure on the lung, causing breathlessness.
In this situation talc cannot work — there are no two surfaces to glue. A PleurX drain controls the problem in a different way. A small, soft silicone catheter is passed through the chest wall and tunnelled under the skin for several centimetres before entering the pleural space. The tunnel and a small built-in cuff act as a barrier against infection. The drain is then connected to a single-use vacuum bottle for ten to twenty minutes at a time, intermittently, to remove the fluid as it forms.
Over weeks, the gentle suction at each drainage gradually re-expands the lung. Many patients live well with a PleurX in place — some have it removed when the lung fully re-expands, others keep it longer for ongoing comfort. Both are good outcomes.
Most of the time, the drain is invisible. It is small and flexible, sits under a waterproof dressing on the lower chest, and is hidden under clothes. Patients can shower with the dressing in place. The only time the drain is undressed is during the 10 to 20 minutes of intermittent drainage, performed by a district nurse — or by the patient or a trained family member — using a single-use vacuum bottle that pulls the fluid out under gentle suction.
The default service is district nurse drainage, typically twice a week. As the suction gradually re-expands the lung over the following weeks, fluid production often slows. When the volume drained at each visit falls below 200 ml, the intervals between drainage can be lengthened to weekly. Some patients and families become confident enough to do the drainage themselves between district nurse visits — the technique is straightforward, the equipment is single-use, and there is no learning curve once it has been demonstrated. District nurses remain contactable for any concern.
Infection along a long-term drain is the obvious concern, and the PleurX has been designed specifically to prevent it. A small polyester cuff sits in the subcutaneous tunnel, just under the skin. Over a few weeks, surrounding tissue grows into the cuff and forms a biological seal that stops bacteria tracking along the catheter into the chest. This is why a tunnelled PleurX is safer for long-term use than a simple chest drain.
Controlling the fluid is often needed before cancer treatment can begin, not just something the drain does not interfere with. Large or recurring pleural fluid weakens the patient — reducing exercise tolerance, respiratory reserve and overall strength — and can become infected if left in place. Drainage and either talc or a PleurX bring the patient back to a level of strength that allows chemotherapy, immunotherapy, targeted therapy or radiotherapy to begin, and to continue safely thereafter. The drain itself does not interfere with any of these treatments.
In most patients, the PleurX stays in for three to six weeks. Over that time the lung is gradually re-expanded by the intermittent suction, fluid production declines, and the intervals between drainage lengthen. When the weekly output falls to around 100 to 200 ml or less, the drain can usually be removed. Removal is a five-minute procedure performed in clinic — the catheter slides out, a small dressing covers the entry point for a few days, and that is it.
For some patients the drain stays in longer. This is particularly true when the goal of treatment is ongoing breathlessness control rather than eventual removal — for example in patients with advanced cancer where the priority is comfort and being out of hospital. In that context the drain may stay in for many months and is considered a success precisely because it has prevented repeat admissions for fluid drainage.
There is also a smaller group of patients who have a PleurX for benign trapped lung — patients in whom past infection or other disease has left a chronically trapped lung, and who are too frail to undergo decortication (a major operation to release the trapped lung), or in whom the risks of decortication outweigh the likely benefit. The same logic applies: the PleurX manages the symptom safely and conservatively where major surgery is not the right choice.
PleurX drains are inserted by interventional radiology and, less commonly, by respiratory physicians, as well as by thoracic surgery. All three routes are valid and patients are sometimes referred along the route that fits their local hospital pathway.
The reason to choose the surgical route is the four-part operation. A VATS pleural biopsy diagnoses the cause, drains the fluid fully, re-expands the lung under controlled pressure, and either treats the recurrence with talc or plans the right long-term drain — all in one operation. When the underlying question has not yet been answered, and the choice between talc and PleurX still needs to be decided by watching the lung, the surgical route does the work in one step that would otherwise take several.
VATS pleural biopsy and PleurX insertion are performed privately at London Bridge Hospital (HCA UK) and The Lister Hospital Chelsea. Both have full anaesthetic, theatre and overnight inpatient capacity. Outpatient consultations are available at LBH, The Lister, and at outreach clinics in Canary Wharf and the City of London. Private appointments are typically available within 2–3 working days. Most major insurers are recognised; self-pay is straightforward to arrange.
Common questions from patients and families before, during and after VATS pleural biopsy and PleurX drainage. If your question is not answered here, please contact Jo Mitchelson.
Book a Consultation →Or call Jo Mitchelson, PA:
020 7952 2882
Appointments within 2–3 working days. Self-referrals welcome. Most major insurers recognised; self-pay straightforward to arrange.
Jo Mitchelson, PA · 020 7952 2882 · pa@lungsurgeon.co.uk
St Thomas’ Hospital #1 UK · Guy’s Hospital #2 UK · London Bridge Hospital #10 UK · Newsweek World’s Best Hospitals 2026
The clinical overview of pleural conditions, surgical approaches and evidence base.
Shadow on a lung scanIf a chest X-ray or CT has shown a shadow or unexplained finding — what comes next.
Cancer that has spread to the lungsA patient guide for those told cancer has spread to the lungs or pleura.
Empyema and pleural infectionWhen the fluid is infection rather than cancer — a different pathway.
ChylothoraxA less common cause of pleural fluid — chyle leak after surgery or related to lymphatic disease.
Second opinionIf you have already had a drainage or a plan elsewhere and would like an independent review.