What are the symptoms?
- The typical symptom is a sharp, stabbing pain on one side of the chest which suddenly develops.
- The pain is usually made worse by breathing in (inspiration).
- You may become breathless. As a rule, the larger the pneumothorax, the more breathless you become.
- You may have other symptoms if an injury or a lung disease is the cause. For example, cough or fever.
Are any tests needed?
A chest x-ray can confirm a pneumothorax. Other tests may be done if a lung disease is the suspected cause.
What are the causes of pneumothorax?
Spontaneous pneumothorax
Most cases are due to a spontaneous pneumothorax. This means that the pneumothorax develops for no apparent reason. It is thought to be due to a tiny tear (rupture) of an outer part of the lung - usually near the top of the lung. It is not clear why this occurs. Air then escapes from the lung but gets trapped between the lung and the chest wall.
Most cases of spontaneous pneumothorax occur in young adults who are healthy and do not have any lung disease. It is more common in tall thin people. Men are affected about four times more often than women. About 2 in 10,000 young men in the UK develop a spontaneous pneumothorax each year. It is also much more common in smokers compared to non-smokers. It is rare in people over the age of 40. About 1 in 10 people who have a spontaneous pneumothorax have one or more recurrences sometime in the future, usually on the same side.
Other causes of pneumothorax
An injury to the chest can cause a pneumothorax. For example, a car crash or a stab wound to the chest. A pneumothorax is also an uncommon complication of some lung diseases such as asthma, emphysema, pneumonia, etc.
What happens to the trapped air and small tear on the lung?
In most cases of spontaneous pneumothorax the pressure of the air that leaks out of the lung and the air inside the lung equalises. The amount of air that leaks (the size of the pneumothorax) varies. Often it is quite small and the lung collapses a little. Sometimes it can be large and the whole lung collapses. If you are otherwise fit and well, this is not too serious as the other lung can cope until the pneumothorax goes. If you have a lung disease, a pneumothorax may make any existing breathing difficulty much worse.
The small tear or 'rupture' that caused the leak usually heals within a few days. Air then stops leaking in and out of the lung. The trapped air of the pneumothorax is gradually absorbed into the bloodstream. The lung then gradually expands back to its original size.
Tension pneumothorax is a rare complication. This causes shortness of breath that quickly becomes more and more severe. This occurs when the 'tear' on the lung acts like a one way valve. In effect, each breath in (inspiration) 'pumps' more air out of the lung, but the valve action stops air coming back into the lung to equal the air pressure. The volume and pressure of the pneumothorax increases. This puts pressure on the lungs and heart. Emergency treatment is needed to release the trapped air.
What is the treatment for pneumothorax?
No treatment may be needed
You may not need any treatment if you have a small pneumothorax. A small pneumothorax is likely to clear over a few days. A doctor may advise an X-ray in 7-10 days to check that it has gone. You may need painkillers for a few days if the pain is bad.
Aspirating (removing) the trapped air is sometimes needed
This may be needed if there is a larger pneumothorax or if you have other lung or breathing problems. As a rule, a pneumothorax that makes you breathless is best removed. It is essential to remove the air quickly in a 'tension' pneumothorax. The common method of removing the air is to insert a very thin tube through the chest wall with the aid of a needle. (Some local anaesthetic is injected into the skin first to make the procedure painless.) A large syringe with a three way tap is attached to the thin tube that is inserted through the chest wall. The syringe sucks out some air, the three way tap is turned, and the air in the syringe is then expelled into the atmosphere. This is repeated until most of the air of the pneumothorax is removed.
Sometimes a larger tube is inserted through the chest wall to remove a large pneumothorax.
Note: It can be dangerous to fly if you have a pneumothorax. Do not fly until you have the 'all clear' from your doctor following a pneumothorax.
Treating recurrences
Some people have repeated episodes of spontaneous pneumothorax. If this occurs, an irritant powder can be put on the lung surface to help it 'stick' to the chest wall better. Sometimes an operation is an option if the part of the lung that tears and leaks air out is identified. It may be a small 'bleb' or harmless cyst on the lung surface that can be removed.
©EMIS and PIP 2006 Updated: June 2006
