Pneumomediastinum refers to the presence of trapped air in the center of your chest. The area between the lungs is called the mediastinum.
The mediastinum contains:
- the heart
- thymus gland
- part of the esophagus and trachea
Primary or spontaneous pneumomediastinum refers to a form of the condition with no obvious cause. Secondary pneumomediastinum is most often caused by injury or trauma, which can cause air leakage from the lungs or digestive tract.
We’ll go over different ways air gets into the mediastinum, what symptoms you may experience, and treatment options.
The main symptom of pneumomediastinum is chest pain. This can come on suddenly and may be severe.
Other symptoms include:
- shortness of breath (dyspnea)
- trouble breathing
- neck pain
- difficulty swallowing (dysphagia)
- a nasal or hoarse voice
Air from the mediastinum can
Your doctor might hear a crunching sound in time with your heartbeat when listening to your chest with a stethoscope. This is called Hamman’s sign, or “mediastinal crunch.”
A differential diagnosis
The symptoms of pneumomediastinum
Fluid leaking from this tear can also get stuck in the mediastinum, and most cases require surgery to repair the hole. Doctors use CT scans and X-rays to identify or rule out this condition.
Pneumomediastinum can happen when
The condition is usually not life threatening and often goes away on its own or with conservative, or noninvasive, treatment.
However, you should always seek medical care when experiencing chest pain and trouble breathing. Pneumomediastinum should be evaluated at a hospital and may require an overnight stay.
Also called spontaneous pneumomediastinum (SPM), this form of the condition doesn‘t result from obvious trauma to the mediastinum or nearby areas. “Spontaneous” refers to its sudden appearance in previously healthy people.
However, certain underlying health conditions or events can raise the pressure inside the lungs and begin the process that leads to SPM.
Smoking and drug use are central risk factors for developing SPM. A
In very rare instances,
Secondary pneumomediastinum has a known or traceable cause. Usually, this is an injury to the mediastinum due to an accident, a medical procedure, or an underlying health condition.
- health conditions that affect the lungs and airways, such as:
- chronic obstructive pulmonary disease (COPD)
- interstitial lung disease (ILD)
- lung cancer
- childbirth (vaginal delivery)
- excessive vomiting or coughing
- strenuous activity or exercise
- medical procedures, including:
- chest or abdominal surgery
- blunt force trauma
- objects penetrating the lungs or mediastinum
- choking on something (windpipe obstruction)
Other causes may include:
- experiencing a sudden change in air pressure, such as while scuba diving or skydiving
- performing the Valsalva maneuver (blowing hard while you’re bearing down, a technique used to pop your ears)
- using a breathing machine, such as a ventilator
Certain factors make you more likely to experience pneumomediastinum.
- Gender. People assigned male at birth make up most cases of pneumomediastinum.
- Lung disease. Pneumomediastinum is more common in people with asthma and other lung diseases.
- Smoking or tobacco use. This damages lung tissue and function over time.
Two imaging tests are used to diagnose pneumomediastinum:
- CT scan. A CT scan uses X-rays to create detailed pictures of your lungs. It can show whether air is in the mediastinum.
- X-ray. An X-ray uses small doses of radiation to make pictures of your lungs. It can help find the cause of the air leak.
These tests can check for a tear in your esophagus or lungs:
- An esophagogram is an X-ray of the esophagus that’s taken after you swallow barium.
- An esophagoscopy passes a tube down your mouth or nose to view your esophagus.
Pneumomediastinum usually isn’t life threatening. The stuck air will eventually reabsorb into your body. The main goal in treating pneumomediastinum is to manage your symptoms and uncover any possible underlying health conditions.
Most people experiencing pneumomediastinum will stay overnight in the hospital for monitoring.
- bed rest
- pain relievers
- anti-anxiety drugs
- cough medication
- antibiotics, if an infection is involved
Some people may need oxygen to help them breathe. Oxygen can also speed up the reabsorption of air in the mediastinum.
Any underlying condition that might have caused the air buildup, such as asthma or a lung infection, will need to be treated. Your doctor may order other labs or imaging tests to investigate.
Pneumomediastinum sometimes happens together with pneumothorax, a buildup of air in the cavity outside the lungs.
Pneumomediastinum and pneumothorax usually both involve chest pain and breathing changes. However, pneumothorax has
- asymmetrical lung expansion (one side inflates more than the other)
- breathing rapidly
- discomfort while breathing
- heart rate is too high (tachycardia)
- turning blue (cyanosis)
- low blood pressure (hypotension)
- bulging jugular vein on neck (jugular vein distention)
If enough air collects and puts pressure on a lung, it can collapse. In this case, doctors may have to extract the air by inserting a needle or tube into your chest cavity. Pneumothorax doesn‘t always lead to a collapsed lung.
Serious pneumomediastinum in newborns and young children is very rare. But mild, temporary spontaneous pneumomediastinum in newborns happens
Pneumomediastinum is more common in babies who:
- are on a mechanical ventilator to help them breathe
- breathe in their first bowel movement (meconium aspiration)
- have pneumonia or another lung infection
- are born by cesarean delivery
Others have symptoms of breathing distress, including:
- abnormally fast breathing
- flaring of the nostrils
Babies with symptoms will receive oxygen to help them breathe. If an infection is identified as the cause of pneumomediastinum, doctors will treat it with antibiotics. Babies are carefully monitored afterward to make sure all the air dissipates.
Pneumomediastinum refers to trapped air in your chest and can happen due to an accident, medical procedure, or unknown cause. It affects people of all ages, but males are more likely to experience it.
Most types of pneumomediastinum resolve with rest and conservative treatment but may require a short stay in the hospital. The majority of patients fully recover with no long-term complications. Recurring pneumomediastinum is rare, but it can occur as a result of a chronic condition (like asthma) or ongoing drug use.
Always contact a doctor if you‘re experiencing chest pain and trouble breathing. Pneumomediastinum can occur on its own or be a sign of an underlying health issue. It‘s important to be promptly evaluated so you can get the care you need.