Pleurodesis is a medical procedure designed to address recurrent fluid buildup around the lungs. It aims to prevent fluid re-accumulation, which can hinder breathing. The process involves creating a bond between the lung’s outer lining and the inner chest wall.
Understanding Pleurodesis and Its Purpose
The lungs are enveloped by two thin membranes known as the pleura. The visceral pleura covers the lung surface, while the parietal pleura lines the inner chest wall. Between these two layers lies a narrow space called the pleural space, which normally contains a small amount of lubricating fluid, typically 10 to 20 milliliters, allowing the lungs to glide smoothly during breathing. When excess fluid, known as a pleural effusion, accumulates in this space, it can compress the lung, making breathing difficult.
Pleurodesis intentionally seals the pleural space, eliminating the cavity where fluid can collect. This procedure is commonly recommended for individuals experiencing persistent or recurring pleural effusions, particularly those caused by conditions like cancer.
Immediate Fluid Removal During the Procedure
Before pleurodesis can prevent future fluid buildup, any existing fluid within the pleural space must be removed. This initial step ensures the lung can fully expand and adhere to the chest wall. The removal of this pre-existing fluid is typically achieved through methods like thoracentesis or chest tube insertion.
Thoracentesis involves inserting a thin needle into the pleural space to drain the fluid. For larger volumes or ongoing drainage, a chest tube is inserted and left in place for a period. This tube allows for continuous drainage of fluid. Healthcare providers carefully manage the rate of drainage to prevent rapid lung re-expansion, which can sometimes lead to discomfort or other complications.
How Pleurodesis Prevents Future Accumulation
Once the pleural space is adequately drained, the primary action of pleurodesis starts to prevent future fluid accumulation. This involves introducing an irritant substance, known as a sclerosing agent, into the pleural space. Common agents include sterile talc powder, or chemical solutions like doxycycline or povidone iodine. Mechanical pleurodesis, an alternative approach, involves physically irritating the pleural surfaces, often during a surgical procedure.
The introduced agent or mechanical irritation triggers an inflammatory reaction within the pleura. This inflammation leads to the formation of fibrous tissue and scarring between the visceral and parietal pleural layers. As the inflammation subsides and scarring progresses, the two pleural membranes adhere firmly to each other, effectively obliterating the potential space between them. With this space sealed, there is no longer a cavity for fluid to collect, thereby preventing recurrent pleural effusions. Talc is widely used due to its effectiveness in achieving this adhesion.
The Body’s Natural Fluid Management
Even after a successful pleurodesis, the body’s fluid management systems continue to operate. The lymphatic system, a network of vessels and nodes throughout the body, plays an important role in maintaining fluid balance. It continuously collects excess fluid and waste products from tissues, including areas around the lungs, and returns them to the bloodstream.
Under normal conditions, there is a balance between fluid production and absorption in the pleural space, primarily managed by capillary filtration and lymphatic drainage. Following pleurodesis, while the large pleural space is intentionally closed off, the lymphatic system in the surrounding tissues remains active. It continues to absorb any microscopic amounts of fluid that might be produced, ensuring that no significant accumulation occurs. This ongoing natural process complements the effects of pleurodesis, contributing to long-term fluid control and respiratory stability.