What are Airway Stents and Valves?
An airway stent is a tube used to keep an airway patent so that the flow of air to and from the lungs is not obstructed.
Airway obstruction can occur due to tumors of the lungs, esophagus, thyroid gland and lymph nodes. It can also occur due to conditions such as tuberculosis, infection and inflammatory disease. Airway stents can help manage such conditions by keeping the airways open to improve breathing. Airway stents are usually made of metal or silicone and can be permanent or removable. They are of different shapes and sizes.
Airway valves are devices that allow one-way passage of air. Air is allowed to leave a damaged part of the lung but cannot enter it. Inhaled air is thus directed only to the healthy parts of the lung and does not get trapped within the damaged portion.
Airway valves and stents may be placed with the help of a bronchoscope, a rigid or flexible illuminated tube with a camera that is inserted through the airway.
What are the Indications for Airway Stents and Valves?
Airway valves are indicated:
- To treat obstruction due to enlarged lymph nodes and tumors within or surrounding the airways
- When there is a loss of supportive cartilage (which keeps the airways patent) due to tumor destruction
- To treat stenosis or stricture of the airways
- To treat stenosis post lung transplantation
- Following surgery to widen a narrow or stenotic airway
- To seal an abnormal communication (fistula) between the trachea and esophagus
An airway stent may not be placed if your condition may be treated by lung surgery as it may cause complications.
Airway valves may be used to treat chronic obstructive pulmonary disease (COPD), a condition with progressive breathing difficulty. COPD is a term used for a collection of lung disorders characterized by chronic bronchitis and emphysema. Airway valves enhance lung function and exercise capacity.
How are Airway Stents and Valves Placed?
Airway stents and valves are placed under anesthesia. A bronchoscope is inserted through your nose or mouth into your windpipe (trachea). The trachea divides into the right and left bronchi that enter each lung. The bronchoscope may be guided into the affected airway or lung segment with the help of live X-ray imaging (fluoroscopy). The stent or valve is then passed through the bronchoscope and placed in the area.
What are the Risks and Complications of Airway Stents and Valves?
Some of the risks and complications associated with airway stents and valves include:
- Wrong stent or valve size
- Wrong positioning of stent or valve
- Stent migration
- Infection
- Allergic reaction or sensitivity
- Impaction of mucus
- Stent or valve damage
- Damage to the airway
What are the Advantages of Airway Stents and Valves?
Airway stents and valves have the following benefits:
- Better lung function with improvement in lung volume, gas transfer and exercise capacity
- Alternative to lung resection surgery
- Can be used for patients who cannot or do not wish to undergo surgery
- Can be used for conditions that are inoperable
- Improves quality of life in critically ill patients
