Chapter 392. Anatomic Disorders of the Esophagus

Congenital atresia of the esophagus and tracheoesophageal fistula occur in 1 of every 2500 to 3000 live births. Other congenital disorders of the esophagus, such as esophageal webs, strictures, duplications, and extrinsic vascular rings are far less common. Acquired esophageal lesions include strictures due to caustic injury, gastroesophageal reflux or eosinophilic esophagitis, and, rarely, diverticula.

The embryologic mechanisms responsible for both normal and abnormal trachea and esophageal development are not fully elucidated. At day 26 or 27 of gestation, a ventral diverticulum is formed from the caudal end of the primitive pharyngeal foregut. This laryngotracheal diverticulum undergoes elongation and differentiation to eventually form the larynx, trachea, bronchi, and lungs. In order to separate the dorsal foregut (future esophagus) from the ventral laryngotracheal diverticulum, longitudinal tracheoesophageal folds fuse to form a septum that completely separates these structures (eFig. 392.1). It is believed that failure of these folds to completely form, or improper timing of their formation, leads to the anomalies of esophageal atresia and tracheoesophageal fistula (TEF).

The genetic factors that lead to malformation of the trachea and esophagus have not yet been elucidated. There is a small increased risk of TEF of about 2% if there is an affected sibling. There are associated anomalies, with cardiac malformations being the most common, in about half of the cases of esophageal atresia (syndromatic esophageal atresia). In the remainder (nonsyndromic cases), esophageal atresia and tracheoesophageal fistula occur in isolation. The specific genes and signaling pathways that lead to esophageal malformations are yet to be determined.1

William Durston first described isolated esophageal atresia (EA) in 1670. He later described 40 cases of EA and tracheoesophageal fistula (TEF) and astutely noted that the fistulas typically arose just proximal to the carinal bifurcation. In 1697, Thomas Gibson was first to describe EA with TEF. Gibson was summoned to care for an infant with aspiration associated with all feeding attempts. The infant died, and on autopsy Gibson noted the EA and TEF. It was not until the 1900s that operative interventions were attempted. The first survivors were reported by William Ladd and N. Logan Leven in 1939. Both used a staged approach that consisted of fistula ligation, cervical esophagostomy, and gastrostomy tube placement. Later esophageal continuity was established via an antethoracic esophagus.2,3 Cameron Haight performed the first successful extrapleural primary repair of an EA and TEF in 1941.4

William Durston first described isolated esophageal atresia (EA) in 1670. He later described 40 cases of EA and tracheoesophageal fistula (TEF) and astutely noted that the fistulas typically arose just proximal to the carinal bifurcation. In 1697, Thomas Gibson was first to describe EA with TEF. Gibson was summoned to care for an infant with aspiration associated with all feeding attempts. The infant died, and on autopsy Gibson noted the EA and TEF. It was not until the 1900s that operative interventions were attempted. The first survivors were reported by William Ladd and N. Logan Leven in 1939. Both used a staged approach that consisted of fistula ligation, cervical esophagostomy, and gastrostomy tube placement. Later esophageal continuity was established via an antethoracic esophagus.2,3 Cameron Haight performed the first successful extrapleural primary repair of an EA and TEF in 1941.4

Clinical Features and Classification

Esophageal atresia (EA) has been classified into 5 types based on whether the esophagus is present and the location of fistula to the trachea. Figure 392-1 illustrates the different types of atresias with their incidence and anatomic findings. The most common type of EA has atresia of the esophagus with a distal tracheoesophageal fistula (TEF) (85%) with an esophageal fistula that typically originates just proximal to the carina in the posterior trachea. The next most common is a pure esophageal atresia without TEF (10%). The blind-ending upper esophageal pouch can have a variable length that determines if primary repair is feasible.

Tracheoesophageal fistula is associated with several other congenital anomalies.5 The most common association is described by the acronym VACTERL and includes anomalies of the vertebrae (similar to those of spondylocostal dysplasia), intestinal atresia, cardiac malformations (patent ductus arteriosus, atrial septal defect, or ventricular septal defect), tracheoesophageal fistula, renal anomalies (urethral atresia with hydronephrosis), and limb anomalies (hexadactyly, humeral hypoplasia, radial aplasia, and proximally placed thumb) (see Table 415-2). Rare cases of VACTERL association in the offspring of an affected individual have been reported, but this is uncommon. eTable 392.1 shows the incidence of anomalies in a large series of patients with esophageal atresia.5 Other associated anomalies include hypospadias, undescended testis, duodenal atresia (as in oculodigitalesophagoduodenal syndrome with gene defect in the 2p24–p23 region), and hydrocephalus secondary to aqueductal stenosis. Genetic syndromes, including oculoauriculovertebral dysplasia (Goldenhar syndrome) and Opitz-G syndrome, can also be associated with esophageal anomalies.

Diagnosis

Polyhydramnios is present in about one third of mothers carrying infants with esophageal fistula with distal tracheoesophageal fistula and in virtually 100% of mothers carrying infants with pure esophageal atresia, apparently due to the inability of the fetus to swallow amniotic fluid. Other antenatal ultrasound findings often include microgastria or a distended upper esophageal pouch.

After birth, the presence of excessive drooling or aspiration and coughing with feeds should lead to an evaluation for esophageal atresia. Confirmation of the diagnosis can be made by attempting to gently pass a 10 French orogastric tube into the stomach. If esophageal atresia is present, a radiograph can be taken while mild pressure is placed on the tube to determine the approximate length of the proximal esophageal pouch. Rib spaces or vertebrae can be counted between the tip of the orogastric tube and the carina to determine the length of the esophageal gap (Fig. 392-2). The site of the carina on chest x-ray can serve as a surrogate for the location of the distal esophageal segment. The chest radiograph also diagnoses a fistula if air is seen in the intestines. This can be in the form of a distal, isolated, or double fistula. Conversely, if the infant has a gasless abdomen, then the diagnosis is true esophageal atresia or a proximal tracheoesophageal fistula. Contrast studies should be avoided due to the risk of aspiration.

In contrast to this typical presentation, patients with H-type fistulas (intact esophagus with a congenital tracheoesophageal fistula) typically present later in life, with repeated bouts of aspiration pneumonia. Because their esophagus is in continuity, they are able to eat; however, they aspirate swallowed or refluxed esophageal contents via the fistula. The diagnosis can be difficult; routine radiographic barium swallows often overlook the fistula. The fistula is best identified by instilling thin barium through the tip of a nasogastric tube, with moderate pressure to distend the esophagus while slowly withdrawing the tube from the stomach into the esophagus. This tends to force the fistula open and allows visualization, as seen in eFigure 392.2A. Repeated radiography and/or rigid esophagoscopy and bronchoscopy may be necessary before the diagnosis is recognized (eFig. 392.2B).

Once the diagnosis of esophageal atresia is made, a search for associated anomalies is required. Radiographs should be performed to evaluate for possible vertebral anomalies. A renal ultrasound is performed to identify renal anomalies. Spinal ultrasound or magnetic resonance imaging should be performed to evaluate for a tethered cord, and a voiding cystourethrogram should be performed at some point prior to discharge. Prior to performing operative repair, it is imperative that an echocardiogram be performed to rule out cyanotic congenital heart anomalies that may require immediate repair and to define the anatomy of the aortic arch, which can determine the surgical approach.

Treatment

Esophageal Atresia with Distal Tracheoesophageal Fistula

Initial management of these infants is focused on minimizing aspiration by elevating the head (>30˚) and inserting an orogastric catheter into the blind upper esophageal pouch. A double-lumen sump-type orogastric catheter should be secured appropriately and connected to low suction. The catheter prevents saliva from pooling in the pouch, and elevation of the head facilitates drainage of secretion into the pouch for suctioning and prevents reflux of gastric contents into the lungs. Antibiotic therapy should be initiated and surgical consultation obtained.

Timing and selection of surgical intervention in patients with esophageal atresia and distal tracheoesophageal fistula is determined by the degree of prematurity, patient weight, overall clinical condition, presence of other associated anomalies, and the length of the gap between the ends of the esophagus. In healthy near-term or full-term infants without other severe anomalies and with minimal pneumonitis, closure of the fistula and primary esophageal anastomosis is typically performed within the first 24 to 72 hours after birth. Usually, the esophageal gap is 1 to 2 cm, allowing primary anastomosis of the 2 ends without tension. This repair can be performed with an extrapleural or transpleural approach. The advantage of the extrapleural approach is the avoidance of pleural contamination if an anastomotic leak occurs. In the case of a straightforward primary esophageal repair, a gastrostomy tube is rarely placed.

Continuous intensive care is crucial in the postoperative period. Intuitively, manipulation of the trachea and esophagus must be avoided in the postoperative period to prevent disruption of the tracheal repair and esophageal anastomosis. These patients are typically intubated postoperatively, and it is imperative to prevent migration of the endotracheal tube and possible perforation of the tracheal closure. To prevent this, the endotracheal tube should be secured adequately to the infant and its location in relation to the mouth noted and checked with nursing assessments and chest x-rays. Deep suctioning, placement, or manipulation of orogastric tubes/nasogastric tubes must be avoided. Depending on the circumstances, the endotracheal tube may remain in place for a few hours to several days. Postoperative nutritional support is provided either parenterally via a Silastic transanastomotic tube placed at the time of surgery for enteral nutrition. An esophagram is typically obtained 5 to 7 days after surgery to check for an anastomotic leak. If no leak is detected, then oral feeds are instituted. If a contained leak is seen, the patient is not fed until the study is repeated in several days.

In infants with severe pneumonia, prematurity, or other significant medical problems, the risk of major surgery is increased, so a gastrostomy tube is placed to allow decompression of the intestinal tract and medical optimization prior to esophageal repair. Head-of-bed elevation and upper pouch suction are maintained until surgery can be accomplished. In the extremely small infant in whom it is apparent that surgical correction of the tracheoesophageal anomaly must be delayed, surgical closure of the tracheoesophageal fistula can be performed in addition to decompressive gastrostomy, allowing gastrostomy feeding. If the esophageal reconstruction will be delayed for an extended period, a cervical diversion esophagostomy may be performed to reduce the risk of aspiration.

A subset of patients with esophageal atresia and distal tracheoesophageal fistula will develop respiratory failure. These patients are unable to deliver adequate tidal volumes because of leakage through the fistula and into the gastrointestinal tract. This can lead to intestinal distension, which inhibits diaphragmatic movement, further compromising respiration. Temporary nonoperative techniques to help improve ventilation while one awaits operative intervention include right mainstem bronchus intubation and high-frequency oscillatory ventilation. Intubation may worsen respiration because positive pressure can exacerbate intestinal distension. However, by placing the endotracheal tube distal to the fistula in the right mainstem bronchus, leakage of the tidal volume and increased gastric distension will be minimized. High-frequency oscillatory ventilation produces small tidal volumes leading to decreased leakage through the fistula. Emergent operative approaches to improve oxygenation include gastrostomy tube placement and fistula ligation and division. Gastrostomy decompression can increase diaphragmatic excursion. Additionally, the gastrostomy tube can be connected to a Pleurovac on water seal to create resistance to air flowing through the fistula. This may result in the tidal volume preferentially going to the lower resistance pathway (the lungs) rather than to the increased resistance in the gastrostomy tube. Definitive treatment of the fistula can be performed by its ligation and division via thoracotomy, but a primary repair of the esophagus is usually not performed at the time of ligation in these unstable patients. A staged approach with initial fistula ligation and division followed by stabilization and later primary esophageal repair is preferred.

Esophageal Atresia Without Tracheoesophageal Fistula

Infants with esophageal atresia without a tracheoesophageal fistula present with excessive oral secretions, drooling, and choking, similar to esophageal atresia and tracheoesophageal fistula patients, but they have a flat, gasless abdomen. If fed, they are unable to swallow, and diagnostic studies confirm the presence of a blind upper esophageal pouch. The length of the atretic segment varies, but a wide gap usually divides the upper and lower ends of the esophagus, thus making primary anastomosis difficult or impossible.

Initial management of these patients includes gastrostomy tube placement and intraoperative determination of the gap length. Primary repair can usually be achieved if the gap is less than 2 vertebral spaces. For gaps spanning 3 to 6 vertebrae, delayed esophageal anastomosis is planned in 2 to 3 months. During this period, a variety of surgical approaches can be attempted to bridge the gap between the 2 esophageal segments in the hopes of achieving a primary repair. These vary from bougienage to novel methods such as placing magnets in each segment to draw the ends closer, thus lengthening both limbs and narrowing the gap. Esophageal lengthening is unlikely to succeed if the gap is wider than 6 vertebrae. In such instances, gastrostomy tube placement and cervical esophagostomy are performed with later esophageal replacement. Conduits for esophageal replacement include gastric tube, gastric transposition, and colonic and jejunal interposition grafts.

Isolated Tracheoesophageal Fistula (H-Type Fistula)

Isolated tracheoesophageal fistulas course obliquely from the posterior trachea to the more caudal anterior esophagus. Infants with isolated tracheoesophageal fistula may present with intermittent episodes of choking during feeding in the newborn period. Others present later with persistent choking episodes, chronic cough, recurrent pneumonias, or reactive airway disease. Presumed congenital isolated tracheoesophageal fistulas have presented in adulthood with only mild symptoms of cough and intermittent pneumonias since childhood. Surgical division of the fistula can be achieved through a cervical approach. No gastrostomy is required, and patients usually have minimal morbidity.

Postoperative Management and Complications

Early complications following surgical repair of esophageal atresias include anastomotic leak, anastomotic stricture, and recurrent fistula. Anastomotic leaks occur in 15% to 20% of patients, with a majority being managed nonoperatively by providing parenteral nutrition and antibiotics until spontaneous closure is documented by a repeat esophagram. Then oral feeding is begun. Major leaks are rare and usually present with tachypnea, sepsis, and/or tension pneumothorax on the second or third postoperative day. Treatment includes tube thoracostomy and possible reexploration.

Stricture formation at the site of the esophageal anastomosis develops in 30% to 40% of patients. Contributing factors to stricture formation include anastomotic tension, ischemia, and leak. Late stricture development is attributed to gastroesophageal reflux. Anastomotic strictures usually respond to repeated dilatation either by radiographic placement of a balloon dilator or by progressive bougie-type dilatation. Recalcitrant strictures may benefit from injection of triamcinolone at the time of dilation,6 although some require resection and secondary anastomosis.

Recurrent tracheoesophageal fistula is thankfully rare with an incidence of 5%. Symptoms of recurrence include coughing, choking, cyanosis, apnea, and recurrent pulmonary infections. Diagnosis can be difficult, and the same techniques described for isolated fistulas are utilized: rigid esophagoscopy/bronchoscopy and withdrawal esophagram via a nasogastric tube. Treatment is surgical and requires division of the fistula.

Gastroesophageal reflux is common after esophageal repair.7 A recent study in postoperative esophageal atresia and tracheoesophageal fistula patients showed the incidence of gastroesophageal reflux doubles from age 6 months to 1 year (16–39%), and then it continues to rise to 51% at age 5.8 Incompetent lower esophageal sphincter, alteration of the angle of His, and poor distal esophageal motility all contribute to gastroesophageal reflux disease with a risk of esophagitis, peptic stricture, and Barrett esophagus. Treatment with proton pump inhibitors is usually adequate. Alternatively, antireflux surgery can be considered. Patients with esophageal atresia/tracheoesophageal fistula should be followed long-term because they are at risk of developing Barrett esophagus and esophageal cancer.9-11

Children who have required an esophageal replacement procedure are at even higher risk of gastroesophageal reflux with ulceration of the interposed segment. In addition, these children often have subclinical gastroesophageal reflux with silent aspiration, resulting in the development of chronic pulmonary disease. Interposed segments, particularly colonic or gastric interpositions, may distend with time, further compromising pulmonary function and occasionally requiring surgical revision.

Other complications include food or foreign impaction either at the site of esophageal structuring or in the aperistaltic segment of the distal esophagus, and dysphagia (particularly for solids) is common because of abnormal peristalsis in the lower esophageal segment. Occasionally, bronchial remnants are associated with tracheoesophageal fistula.

The overall prognosis after surgical repair of esophageal atresia and tracheoesophageal fistula depends on the type of anatomic abnormality and the presence of other anomalies. In general, survival is greater than 90%, and most patients have normal life expectancy and productive lives.

Congenital esophageal stenosis12 and web diaphragms13 rarely occur (ie, one in 25,000 live births) and usually present with dysphagia when feeds are advanced to pureed or solid consistencies. Diagnosis is made by radiographic contrast studies or endoscopy (Fig. 392-3). Webs and fibromuscular stenosis14 can usually be successfully dilated using endoscopy and/or fluoroscopic-guided balloon or bougie-type dilators. Stenosis resulting from ectopic cartilage (ie, tracheobronchial remnant) is diagnosed by endoscopy, and confirmation of its cartilaginous component can be provided by endoscopic ultrasound. The ectopic cartilage is more irregular and firmer than fibromuscular stenosis, and it should be treated by surgical resection rather than dilation because of the risk of esophageal perforation with dilation.

Esophageal duplications are rare lesions that present as a tubular mass in the posterior mediastinum. Secretions cause distension with pressure on contiguous structures that can cause dysphagia or respiratory symptoms. Surgical excision is curative.

Congenital esophageal diverticula are rare true diverticula lesions usually found in the muscle just above the cricopharyngeus. They may present with symptoms of choking, coughing, and dysphagia in older children. More commonly, acquired pseudodiverticula occur in neonates after traumatic efforts at airway intubation. Perforation results in infection and edema, which leads to the pseudodiverticulum and, occasionally, progression to obstruction. Antibiotic therapy and the cessation of oral feedings can be sufficient to treat the perforation if it is diagnosed soon after it occurs. Acquired diverticula may follow histoplasmosis infection15 or may result from a retained foreign body.16 They may also occur in children with Ehlers-Danlos syndrome.17Acquired esophageal strictures may also result from caustic ingestion, gastroesophageal reflux (peptic strictures), and eosinophilic esophagitis.