What is a diaphragmatic hernia?

The diaphragm is a dome-shaped muscular barrier between the chest and abdominal cavities. It separates your heart and lungs from your abdominal organs (stomach, intestines, spleen, and liver).

A diaphragmatic hernia occurs when one or more of your abdominal organs move upward into your chest through a defect (opening) in the diaphragm. This kind of defect can be present at birth or acquired later in life. It’s always a medical emergency and requires prompt surgery to correct.

A congenital diaphragmatic hernia (CDH) is due to the abnormal development of the diaphragm while the fetus is forming. A defect in the diaphragm of the fetus allows one or more of their abdominal organs to move into the chest and occupy the space where their lungs should be. As a result, the lungs can’t develop properly. In the majority of cases, this affects only one lung.

An acquired diaphragmatic hernia (ADH) is usually the result of a blunt or penetrating injury. Traffic accidents and falls cause the majority of blunt injuries. Penetrating injuries are usually due to stab or gunshot wounds. Surgery on the abdomen or chest may also cause accidental damage to your diaphragm. Rarely, the diaphragmatic hernia may occur without a known reason and go undiagnosed for a period of time, until it becomes severe enough to cause symptoms.

Most congenital diaphragmatic hernias are idiopathic; their cause is unknown. It is believed a combination of several factors lead to their development. Chromosomal and genetic abnormalities, environmental exposures and nutritional problems may all have a role in the formation of these hernias. It can also occur with other organ problems such as abnormal development of the heart, gastrointestinal, or genitourinary systems.

The following factors may increase your risk of an acquired diaphragmatic hernia:

  • blunt injuries due to a traffic accident
  • surgical procedures on the chest or abdomen
  • falls that impact the diaphragm region
  • stab wounds
  • gunshot wounds

The severity of symptoms with a diaphragmatic hernia can vary depending on its size, cause, and the organs involved.

Difficulty breathing

This is usually very severe. In a CDH, it results from the abnormal development of the lungs. In an ADH, it occurs when the lungs can’t function properly due to crowding.

Tachypnea (rapid breathing)

Your lungs may try to compensate for the low levels of oxygen in your body by working at a faster rate.

Blue discoloration of the skin

When your body doesn’t receive enough oxygen from your lungs, it can make your skin appear blue (cyanosis).

Tachycardia (rapid heart rate)

Your heart may pump more rapidly than normal to try to supply your body with oxygenated blood.

Learn more: What is arrhythmia? »

Diminished or absent breath sounds

This symptom is common in the case of a CDH because one of the baby’s lungs may not have formed properly. The breath sounds on the affected side will be absent or very difficult to hear.

Bowel sounds in the chest area

This occurs when your intestines move up into your chest cavity.

Less full abdomen

Your abdomen may be less full than it should upon palpation (an examination of the body by pressing on certain areas). This is due to abdominal organs being pushed up into the chest cavity.

Doctors can usually diagnose a congenital diaphragmatic hernia before the baby is born. About half the cases are revealed during an ultrasound examination of the fetus. There may also be an increased amount of amniotic fluid (the fluid that surrounds and protects the fetus) within the uterus.

After birth, the following abnormalities may appear during a physical examination:

  • abnormal chest movements
  • difficulty breathing
  • blue discoloration to the skin (cyanosis)
  • absent breath sounds on one side of the chest
  • bowel sounds in chest
  • a “half-empty” feeling abdomen

The following tests are usually sufficient to diagnose either a CDH or an ADH:

  • X-ray
  • ultrasound scan (uses sound waves to produce images of the thoracic and abdominal cavities and their contents)
  • CT scan (allows for direct viewing of the abdominal organs)
  • arterial blood gas test (takes blood directly from an artery and tests for levels of oxygen, carbon dioxide, and acidity, or pH level)
  • MRI (for more focused evaluation of organs especially in a fetus)

Both congenital and acquired diaphragmatic hernias typically require urgent surgery. Surgery must be performed to remove the abdominal organs from the chest and place them back into the abdomen. The surgeon will then repair the diaphragm.

With a CDH, surgeons may perform surgery as early as 48 to 72 hours after the baby is delivered. Surgery may occur earlier in emergency situations or it may be delayed. Every case is different. The first step is to stabilize the baby and increase its oxygen levels. A variety of medications and techniques are used to help stabilize the infant and assist with breathing. These babies are best cared for at a center with a highly specialized Neonatal Intensive Care Unit (NICU). Once the baby stabilizes, then surgery can occur.

Learn more: Endotracheal intubation »

With an ADH, the patient typically needs to be stabilized before surgery. Because most cases of ADH are due to injury, there might be other complications such as internal bleeding. Therefore, the surgery should happen as soon as possible.

Currently, there is no known way to prevent a CDH. Early and regular prenatal care during pregnancy is important to help detect the problem before birth. This allows for proper planning and care before, during, and after delivery.

Some basic preventive measures that can help you avoid an ADH include:

  • Driving safely and always wearing a seat belt.
  • Avoiding activities that make you prone to significant blunt injuries to the chest or abdomen, such as extreme sports.
  • Limiting alcohol and avoiding drug use which can make you more prone to accidents.
  • Exercising caution around sharp objects, such as knives and scissors.

The outlook for a CDH depends on how damaged the lungs are, as well as the severity of involvement of other organs. According to current research, the overall survival rate for congenital diaphragmatic hernias is 70-90 percent.

The survival rate for an ADH correlates directly with the type of injury, age, and overall health of the individual, as well as the severity of the hernia based on the size and other organs involved.