Pneumothorax in Premature Babies

Pneumothorax and Other Types of Air Leaks

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In a pneumothorax, air leaks into the space between the lung and the chest wall. Image copyright A.D.A.M.

What is a Pneumothorax?

A pneumothorax is a type of collapsed lung where air collects inside the chest cavity, between the lungs and the chest wall. A pneumothorax, sometimes called just a "pneumo," can be mild or severe depending on how much air is present.

A pneumothorax can be caused by air entering the chest from outside the body or from the lungs themselves. In the NICU, most pneumos occur when air from inside the lungs leaks out.

A pneumothorax is just one type of air leak. If the air goes someplace other than the chest cavity, the air leak has a different name.

What Causes Pneumothorax?

A pneumothorax or other air leak develops when the alveoli, the tiny air sacs in the lungs where oxygen and carbon dioxide are exchanged, burst. When the alveoli burst, the air escapes and causes an air leak.

Babies have very fragile lungs, and many things can increase a baby's risk of pneumothorax or other air leaks. Although some babies are at greater risk than others, any newborn can develop a pneumo as their lungs expand after birth. Risk factors that give your baby a greater chance of developing a pneumo include:

  • Premature birth: Preemies have very fragile lung tissue, and their alveoli rupture easily. Babies who weigh less than 1500 g (3 lb 5 oz) at birth are at greatest risk.
  • Help breathing at birth: When babies don't breathe right away after birth, the resuscitation team will use an ambu bag or other device to give manual breaths until the baby begins to breathe. Although necessary, this help breathing can cause a pneumo.
  • Mechanical ventilation: Babies who need extended help breathing, either from a ventilator or from CPAP, have a higher risk of pneumo. This is because mechanical ventilation forces air into the lungs to keep them inflated and keep the baby's oxygen levels up.
  • Meconium aspiration: Babies who breathe in meconium during the birth process can be very sick. Meconium can plug the airways, allowing air to get into but not out of the lungs. This air trapping can increase pressure in the alveoli and cause them to burst.

    How is a Pneumothorax Treated?

    If doctors think your baby has a pneumo, they will do a chest x-ray to confirm their diagnosis. If no x-ray is available, they may shine a light through your baby's chest (transillumination) to look for bright spots where air has collected.

    Treatment for air leaks depends on how bad the symptoms are and how big the air leak is. Babies with small leaks may have no symptoms at all and may not require treatment. The leak will heal on its own, and the body will reabsorb the air.

    A large pneumo can cause a baby to have significant trouble breathing. The buildup of air can push the heart, major blood vessels, and windpipe out of the correct position and can become a medical emergency. Treatment is based on the severity of the symptoms, and may include:

    • Supplemental oxygen: In some cases, giving a baby 100% oxygen can help the body to reabsorb air from a pneumo. This technique is only used in term babies due to the risk of ROP in preemies.
    • Needle aspiration: A needle attached to a syringe can be inserted through the chest wall and used to withdraw the air that has collected. This needle is then removed and the skin bandaged.
    • Chest tube: In severe pneumothorax or in premature babies on a ventilator, a chest tube is often used to remove air until the air leak has resolved. A thin plastic tube will be inserted into the baby's chest and secured, then connected to suction. The suction will remove air as it accumulates. The chest tube will be removed after all of the extra air is removed and the leak has healed.

    After a pneumothorax is treated, doctors will repeat a chest x-ray to make sure the leak is healed and no new air has accumulated.

    References: 

    University of Rochester Medical Center Health Encyclopedia. "Pneumothorax." Accessed from http://www.urmc.rochester.edu/Encyclopedia/Content.aspx?ContentTypeID=90&ContentID=P02397

    Rennie, J.(2012). Rennie & Robertson's Textbook of Neonatology, 5th ed. Elsevier.

    Litmanovitz, I. & Carlo, W. (Nov. 2008). "Expectant Management of Pneumothorax in Ventilated Neonates." Pediatrics, 122(5); e975-e979.

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