Esophageal Atresia

Esophageal atresia (or Oesophageal atresia) is a congenital medical condition (birth defect) that affects the alimentary tract. It causes the esophagus to end in a blind-ended pouch rather than connecting normally to the stomach. It refers to a group of congenital anatomic defects caused by abnormal esophageal embryological development. It is distinguished anatomically by a congenital obstruction of the throat with obstruction of the persistence of the esophageal wall.

Classification:

This condition conveys itself in a variety of ways, often involving one or more fistulas connecting the trachea to the esophagus (tracheoesophageal fistula).

Type D

Diagnosis:

This condition is detectable on ultrasound after about 26 weeks. The presence of an absent or small stomach on antenatal USG in the setting of polyhydramnios was considered a potential symptom of esophageal atresia. These findings, however, have a low positive predictive value. Another sign that aids in the antenatal diagnosis of esophageal atresia in the upper neck pouch sign, which can be detected soon after birth because the affected infant is unable to swallow its own saliva. In addition, the newborn may exhibit gastric distention, cough, apnea, tachypnea, and cyanosis. A feeding tube will not pass through the esophagus in many cases of esophageal atresia.

Complications:

Any feeding attempt may result in aspiration pneumonia, as milk collects in the blind pouch and overflows into the trachea and lungs. A fistula between the lower esophagus and the trachea may also allow stomach acid to enter the lungs and cause damage. Because of these risks, the condition must be treated as soon as possible following birth.

Treatment:

Treatment options for the condition vary according to its severity. In the majority of cases, the most immediate and effective treatment is a surgical repair to close the fistula/s and reconnect the two ends of the esophagus. Although this is usually done through an incision between the ribs on the baby's right side, some centers use a technique that involves three small incisions (thoracoscopy). In a small number of cases, the gap between the upper and lower esophageal segments is too large to bridge. However, in some of these so-called long gap cases, an advanced surgical treatment developed by John Foker, MD, may be used to elongate and then join the short esophageal segments.

Using the Foker technique, surgeons insert traction sutures into the tiny esophageal ends and gradually tighten the sutures until the ends are close enough to be sewn together. The end result is a normally functioning esophagus that is virtually indistinguishable from one that was formed at birth. Unfortunately, other surgeons have found it difficult to replicate the results, and the need for multiple operations has dampened enthusiasm for this approach. The best treatment for long gap esophageal atresia is still debatable.

Gastrostomy followed by gastric pull-up, colonic transposition, and jejunum transposition is all traditional surgical approaches. Many specialized centers, including Great Ormond Street (London) and Mott Children's Hospital, have preferred the gastric pull-up approach (Ann Arbor). Gastrostomy, also known as a G-tube, is a surgical procedure that allows tube feedings into the stomach through the abdominal wall. A cervical esophagostomy is frequently performed to allow swallowed saliva to drain through a hole in the neck. Months or years later, the esophagus may be repaired, sometimes by inserting a segment of the bowel into the chest and interposing between the upper and lower esophageal segments.

Post-operative complications can occur, including a leak at the site of esophageal closure. A stricture, or tight spot, can form in the esophagus, making swallowing difficult. Using medical instruments, this is usually dilated. In later life, most children with this disorder will experience difficulty swallowing, heartburn, or both. 75-100 percent of patients have esophageal dysmotility.

Another serious complication is tracheomalacia, which is a softening of the trachea, usually above the carina (tracheal carina), but can be widespread in the lower bronchial tree. Even after anastomosis, the relative flaccidity of the former proximal pouch (blind pouch, above) combined with esophageal dysmotility can cause fluid buildup during feeding. Because of the close proximity, pouch ballooning can result in tracheal occlusion.

Severe hypoxia ("dying spells") ensues, and medical intervention is frequently required. There are several treatments available for tracheomalacia caused by esophageal atresia. If the condition is not severe, it can be managed predictably because the trachea usually stiffens as the infant matures into the first year of life. When only the trachea above the carina is compromised, one of the "simplest" interventions is aortopexy, which involves attaching the aortic loop to the back of the sternum and mechanically relieving pressure from the softened trachea. Stenting is an even simpler intervention. However, epithelial cell proliferation and potential stent incorporation into the trachea can make subsequent removal risky.