Prof Dr R Narasimhan MD FRCP (UK) Head EBUS Services, Department of Respiratory Medicine, Apollo Hospitals, Chennai
Pleural effusion is a condition where fluid accumulates in the pleural cavity. Pleural membrane is a layer that covers the lung. It has a visceral pleura that is close to the lungs and parietal pleura that is close to chest wall. Fluid accumulation between the two layers of the pleura is called pleural effusion. Any inflammation of the pleura without fluid accumulation is called pleurisy.
Traditionally pleurisy or pleural effusion or pleurisy has been considered to be synonymous with tuberculosis in our country. You ask any doctor in the age group of 75 and above and without batting an eyelid they will advise anti-TB treatment. This kind of unscientific approach is wrong. We would have missed and treated many pleural effusions as tuberculosis wrongly. In these days of scientific and technological improvements it is wrong to treat without a proper diagnosis.
I remember, a 42-year-old individual who was with pleural effusion and had been started on anti-TB treatment. The individual developed side effects to anti- TB drugs and decided to go for definitive diagnosis. He underwent a pleuroscopic biopsy and was diagnosed to have malignancy. His anti-TB treatment was stopped and the treatment for malignant effusion was started.
In pleural cavity
• Air can accumulate called pneumothorax
• Yellow coloured fluid can accumulate
• Blood can collect called hemothorax
• Pus can accumulate called empyema
• Chyle can accumulate called chylothorax.
Common causes of Pleural Effusion
The commonest cause of pleural effusion is tuberculosis. But other diseases can also lead to such clinical situations. Simple pleural aspiration can tell us if it is blood or pus or fluid. The fluid so removed has to be sent for biochemical analysis, microbiological analysis and pathological analysis. The most important part of this analysis is pathological analysis. A pleural biopsy of the pleura will clinch the diagnosis, but to get the pleura is difficult, this is because pleural biopsies done through needles are successful only in tuberculosis and there too it varies from centre to centre. In tuberculosis, tubercles are spread across the pleura, so biopsy is always successful if the technique is good. Faulty biopsy techniques will result in needless pain, muscle being biopsied and negative reports.
After the pleural biopsy is done all the fluid is removed and a tube is left in place so that whatever fluid accumulates is drained out. If malignancy is suspected, a medicine can be injected so that adhesions develop and further fluid can accumulate. Similarly if there are too many adhesions preventing the lung expansion adhesiolysis can be done.
So with this ingenious tool from Olympus called flexible pleuroscope one can have access to pleural cavity with ease. Its fascinating history has bridged continents and specialties and is intimately related to the history of optics and optical technologies. During the last decade, advances in video technology and improved endoscopic instrumentation have prompted a resurgence of interest in minimally invasive chest procedures among thoracic surgeons and interventional pulmonologists, and today, there is renewed enthusiasm for pleural investigations to manage both simple and complex pleural diseases.
An instrument called pleuroscope is used to get at the pleura under vision. The pleuroscope is a semi-rigid instrument. It is introduced in to the pleural cavity under anaesthesia. The pleuroscope is a fibreoptic instrument that can be used to take biopsies of the pleura. A pulmonologist who uses the bronchoscope can use this with ease. This procedure is known as medical pleuroscopy or medical thorascopy. It can be used
1. To visualise the pleura
2. To remove all the pleural fluid and give symptomatic relief
3. Allows the explanation of unexplained pleural effusion
4. Obtain pleural tissue samples for analysis
5. To remove adhesions so that lung can expand nicely
6. Perform pleurodesis or other therapeutic interventions
7. Inject medications in to the pleural space.
8. To relieve pain and dyspnea
9. Occasionally do lung biopsies
10. Has a therapeutic role in pneumothorax