Atelectasis is a medical condition characterized by the partial or full collapse of a lung, impairing the patient's ability to breathe. Left untreated, atelectasis can be fatal, as oxygen is a vital requirement for a healthy body. There are a number of causes for atelectasis, and each cause requires a different treatment approach; treatment usually focuses on ensuring that the patient has enough oxygen before the root cause of the problem is addressed and hopefully resolved.
This condition affects the alveoli, the tiny air sacs which line the lungs. These sacs are very flexible, allowing them to inflate to take in oxygen, and then to deflate, pushing the oxygen through the blood-rich tissues of the lungs so that it can be carried off to other parts of the body. When the alveoli cannot inflate, the lung may start to collapse, preventing the lung from inflating with air and restricting the supply of available oxygen to the patient. Atelectasis can also occur in patients who do not have enough pulmonary surfactant, the material which reduces the surface tension of the alveoli so that they do not collapse after the patient respires.
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One of the most common causes of atelectasis is surgery, and this is one of the reasons why the airway is monitored very carefully after surgery. Smokers are also encouraged to stop smoking for six to eight weeks before surgery, because they are at increased risk. Atelectasis can also be caused by trauma to the lungs, a buildup of mucus, or an obstruction such as a foreign object or tumor.
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In congenital atelectasis, an infant is born without the ability to inflate one or both lungs. This condition can occur in premature infants especially, because their bodies are not fully developed, and it typically requires medication to help the lungs build up surfactant while the lungs are inflated with the assistance of a ventilator, which helps the baby to breathe. This condition is sometimes referred to as infant respiratory distress syndrome, and it can also occur in infants with genetic conditions which cause reduced surfactant production.
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In cases where the whole lung is collapsed, a ventilator may be needed to breathe for the patient. In other instances, the airway can be cleared with suction to remove blockages, freeing the flow of air and allowing the alveoli to inflate on their own. In the case of a cause such as a tumor or trauma, surgery may be needed to correct the problem so that the patient can breathe normally.