Congenital Diaphragmatic Hernias: Diagnosis, Surgery and Recovery

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What is a Congenital Diaphragmatic (Bochdalek) Hernia?

Bochdalek Diaphragmatic Hernia Image Surgery
Diaphragmatic (Bochdalek) Hernia Image. Image: © ADAM

A congenital diaphragmatic hernia, or Bochdalek hernia, happens in the womb and is diagnosed during pregnancy or in a newborn. It occurs when there is a weakness in the diaphragm, the muscle that divides the chest cavity from the abdominal cavity. In addition to separating the organs of chest from the organs of the abdomen, the diaphragm also helps the lungs fill with oxygen. (The movement of the stomach area that you see when you breathe is the movement of the diaphragm.)

A severe diaphragmatic hernia can allow an entire organ or organs to slip in to the chest, through the hole or defect. In most cases, a diaphragmatic hernia is an emergency, requiring immediate surgical treatment. This is because the heart and lungs have difficulty filling and providing the body with oxygen because of the crowding of the chest cavity. A newborn with this type of hernia may have lips that appear bluish, due to a lack of oxygen.

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Causes and Risk Factors

Causes of a Congenital Diaphragmatic Hernia

There is no known cause of a diaphragmatic hernia. The weakness in the muscle is present at birth, also called a "congenital defect." There is no way to prevent a diaphragmatic hernia, as they form in utero, before the baby is born.

Who Is At Risk for a Congenital Diaphragmatic Hernia?

Diaphragmatic hernias happen in 1 out of every 2,000 to 5,000 births. There does appear to be a genetic link involved with this type of hernia, as a baby may have an increased risk of having this type of hernia if a sibling or a parent had the condition. Boys have a slightly higher risk than girls.

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Diagnosis

A diaphragmatic hernia does not have the appearance of a bulge under the skin like most hernias. In many cases, there are no visible signs that a newborn has this type of hernia. It will be diagnosed with an ultrasound before the baby is born, or after the birth when the abdomen feels suspiciously “empty” when a physical exam is performed. In some cases, the hernia may be discovered when doctors are searching for an explanation for the breathing difficulty a newborn is experiencing.

A diaphragmatic hernia happens most commonly on the baby’s left side, making it common for the stomach to slip through the defect. In mild cases, where only the stomach is involved, the baby may only exhibit symptoms of difficulty feeding and vomiting.

Tests may be ordered to determine which organs are being affected by the problem. An echocardiogram may be ordered to examine the heart’s function; a chest x-ray, CT scan or MRI may be used to evaluate additional organs. Blood tests may also be ordered to determine how much oxygen is reaching the blood in addition to standard lab work.

Signs of a Diaphragmatic Hernia

  • A rapid heart rate (the heart trying harder to get oxygen to the body)
  • A rapid rate of breathing (the lungs trying harder to get oxygen to the body)
  • Cyanosis (blue lips and fingernail beds)
  • Unexplained, severe breathing problems
  • The diagnosis of excessive amniotic fluid during pregnancy
  • The diagnosis of a collapsed lung
  • One side of the chest is notably larger than the other
  • Severe problems eating or keeping food down
  • A chest x-ray shows abnormalities in the chest

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When Is a Congenital Diaphragmatic Hernia an Emergency?

A diaphragmatic hernia can be an emergency for multiple reasons. The baby may have great difficulty breathing, as the extra organs in the chest make it hard for the lungs to expand. This is also true of the heart; it can be difficult for the heart to fill with blood because of the overfilling of the chest.

In addition, there is a risk of strangulation of the organs that are pressing in to the chest, meaning that the organs that have moved in to the chest are being deprived of blood flow. This can cause the death of the tissue and organs that are bulging through the hernia.

Babies born with diaphragmatic hernias are typically cared for in an intensive care unit due to the serious complications that are often present. Despite the fact that babies born with a diaphragmatic hernia are critically ill, surgery may still be delayed until lung function is stabilized, as this can improve the chances of surviving the surgery.

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Congenital Diaphragmatic Hernia Surgery

Diaphragmatic hernia surgery is typically performed using general anesthesia and is done on an inpatient basis. It may be performed emergently, immediately after the birth of the child, or as soon as the child is stable enough to tolerate surgery. In some cases, there may be a need to stabilize the child’s breathing or heart function before surgery can be done. In very rare circumstances, surgery in utero may be considered, a procedure where surgery is performed on the fetus while the mother is pregnant. The fetus is then allowed to continue developing while the pregnancy continues, although the pregnancy becomes very high risk.

The surgery, when performed on a newborn, is done by a pediatric general surgeon, but may require the assistance of other surgeons, such as acardiothoracic surgeon or a colon-rectal specialist in severe cases. Depending upon the organs affected, different or additional surgeons with varying expertise may participate in the surgery.

The surgery is usually performed with an open approach using a standard incision just below the rib cage, rather than the less invasive laparoscopic method. This is due to the severity of the problem combined with the very small size of the patient.

The surgery begins with locating the defect in the diaphragm and the tissue that has pushed in to the chest area. The tissue and organs, if present, are placed back in the abdomen. Once the tissues are returned to their proper place, the hole in the diaphragm is closed. This is done to prevent the abdominal tissues from migrating back in to the chest cavity. If the defect in the diaphragm is very severe, a diaphragm may be created from synthetic materials.

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Recovering from Diaphragmatic Hernia Surgery

Most hernia patients are critically ill at the conclusion of surgery and will be taken to the Neonatal Intensive Care Unit (NICU) to recover. For the rare patients who are able to breathe on their own shortly after surgery, expect a fussy baby who is uncomfortable and at times, difficult to console.

If the baby’s lungs are underdeveloped or if breathing problems persist after the surgery, a ventilator may be necessary during the recovery. In some severe cases, the ventilator is not enough to deliver adequate oxygen to the body. In these cases ECLS/ECMO (Extracorporeal Life Support/Extracorporeal Membrane Oxygenation) may be used, a machine that helps to oxygenate the blood when the lungs and heart are unable to do so. This treatment is only used in the sickest patients, those who would die without additional oxygen being delivered to the body.

The length of time the baby spends in the ICU is largely dependent upon how severe the hernia was, if there was any organ damage and how well developed the organs are.

Unfortunately, this condition is very serious and some babies do not tolerate the surgery. Other children make it through the surgery, but the combination of the surgery, underdeveloped organs or organ damage result in death. It is estimated that 80% of patients survive the surgery and recovery.

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Long-Term Consequences of Diaphragmatic Hernias

A diaphragmatic hernia can cause problems before the baby is even born. The lungs and heart of the baby may not develop normally, because of the pressure caused by the additional tissue in the chest. The tissue or organs that slip in to the chest may also be damaged or fail to develop properly due to a lack of blood flow. This can result in ongoing breathing problems, heart problems and nutritional issues.

These patients often experience developmental delays, which may diminish over time. In some, a failure to thrive diagnosis accompanies the long-term inability to get enough oxygen to the body.

More Information: All About Hernias

Sources:

Congenital Diaphragmatic Hernia. The University of Michigan Health System. http://surgery.med.umich.edu/pediatric/clinical/physician_content/a-m/congenital_diaphragmatic.shtml

Diaphragmatic Hernias. The Lucile Packard Children’s Hospital at Stanford http://www.lpch.org/diseasehealthinfo/healthlibrary/digest/diaphrag.html

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