Esophageal atresia

Esophageal atresia is a congenital defect in which the upper esophagus is not connected to the lower esophagus, ending blindly instead. It is caused by the abnormal development of the tracheoesophageal septum. Esophageal atresia with a fistula connected distally to the trachea is the most common kind of esophageal malformation (classified as Gross type C). It manifests immediately after birth with cyanotic attacks, foaming at the mouth, and coughing, and prevents any attempts to pass a feeding tube into the stomach. X‑ray is mandatory for classifying the atresia and should show an air‑filled pouch situated at the level of the third thoracic vertebra. Infants with suspected esophageal atresia cannot be fed orally because of the risk of aspiration pneumonia. Curative surgery must, therefore, be performed within the first 24 hours after birth.

References:^[2][3]

• Incidence: approx. 1:4,300 live births in the US ^[4]

Epidemiological data refers to the US, unless otherwise specified.

• A wedge of mesoderm called the tracheoesophageal septum separates the developing foregut (esophagus) from the trachea.
• Esophageal atresia and tracheoesophageal fistula are caused by a defect in mesodermal differentiation
• About 50% of cases are associated with other mesodermal defects (VACTERL association) ^[2]
  • Vertebral anomaly
  • Anal atresia
  • Cardiac anomaly
  • Tracheoesophageal fistula
  • Esophageal atresia
  • Renal anomaly
  • Limb malformation

References:^[5]

Esophageal atresia

• Definition: a congenital defect in which the upper esophagus is not connected to the lower esophagus and ends blindly instead
• Prenatal features
  • Polyhydramnios
    • The fetus is unable to swallow amniotic fluid.
    • Occurs in approx. 57% of pregnancies ^[6]
  • Associated with an increased risk of premature birth ^[2][7][8]
• Postnatal features
  • Pooling of secretions → excessive secretions/foaming at the mouth ^[2]
    • Choking, drooling
    • Inability to feed
    • Vomiting

Tracheoesophageal fistula

• Definition: an abnormal connection between the trachea and esophagus that may be connected to the proximal and/or distal esophageal segment
• Postnatal features
  • Aspiration and subsequent aspiration pneumonia (especially if the fistula is connected to the proximal esophageal segment)
    • Coughing spells
    • Rales
    • Cyanotic attacks due to reflex laryngospasms that prevent reflux aspiration
  • If the fistula is connected to the distal esophageal segment: gastric distention ^[3][7]

Newborns usually present with symptoms directly after birth. The exception is Gross type E fistula, in which the diagnosis of a small H-type tracheoesophageal fistula may occur as late as adulthood.

• Placement of a feeding tube: the feeding tube cannot pass through the esophagus in the case of esophageal atresia ^[2]
• X-ray of the thorax/abdomen ; ^[2]
  • Esophageal pouch (except with an H‑type fistula)
  • Large gastric bubble: air in the stomach (gross types A and B present with a gasless abdomen)
• Further diagnostics concerning VACTERL anomalies
  • Ultrasound of the abdomen
  • Echocardiography

Double aortic arch

• Definition: : an embryonic malformation resulting in a double aortic arch (vascular ring anomaly; ) with subsequent constriction of the trachea and esophagus
• Etiology: associated with CHARGE syndrome, DiGeorge syndrome, trisomy 21
• Pathophysiology
  • The right and left pharyngeal arch arteries persist postnatally → formation of a vascular ring (double aortic arch) → constriction of the trachea and esophagus.
  • Feeding → ↑ constriction of the trachea → exacerbation of respiratory symptoms
• Clinical features ^[9]
  • Typically manifests within the first weeks of life, especially in cases of tracheal compression
  • Tracheal constriction: inspiratory and expiratory stridor, dyspnea, respiratory arrest
    • Acute episodes of severe constriction and/or apnea with cyanosis may occur (can be life-threatening)
    • Hyperextension of the head to improve airflow
  • Esophageal constriction: dysphagia, choking, retching, vomiting, failure to thrive
• Diagnostics
  • Chest x-ray (anteroposterior and lateral): shows anterior tracheal bowing and narrowing
  • Echocardiography: to identify anomaly and associated congenital heart defects (e.g., VSD, tetralogy of Fallot, PDA)
  • Chest CTA or MRA: to visualize the extent of compression and the relationship of the trachea, esophagus, and vessels preoperatively
• Treatment: surgical division of the minor arch ^[9]

Other

The differential diagnoses listed here are not exhaustive.

Preoperative

• Placement of an oroesophageal or nasoesophageal tube for continuous suction of secretions to prevent aspiration and facilitate breathing ^[2][3]
• Upper body elevated, left lateral decubitus position ^[3]
• Antibiotics in case of aspiration pneumonia ^[7]

Infants who potentially have esophageal atresia should not be fed orally under any circumstances!

Surgery

Surgical treatment should be performed within the first 24 hours of birth.

• The goal is to reconnect the upper esophageal pouch and the lower esophagus. ^[3]
• A long gap between both ends of the esophagus may not allow primary repair. ^[2]
  • In this case, a gastrostomy tube is necessary to allow enteral feeding.
  • Treatment options include promoting elongation of the esophagus (via the Foker technique) and colon interposition

Postoperative

• Uncomplicated surgery: transition to a normal diet after 2–3 days ^[3]
• Anastomosis under tension: postoperative ventilation (for approx. 5 days)
• Radiological examination with a contrast agent (esophagram) one week after surgery to identify complications: e.g., esophageal stricture or anastomotic leak ^[2]
• Approx. 4 weeks after the procedure: Gastroscopy (EGD) and dilation of the anastomosis may be necessary.

Overall good prognosis, but surgical complications occur frequently:

• Dysphagia
• Gastroesophageal reflux disease
• Anastomotic stenosis
• Wheezing
• Infections of the respiratory tract
• Anastomotic insufficiency
• Recurrence of esophageal tracheal fistula
• Esophageal stricture

The overall survival of esophageal atresia is good (> 85%) but decreases when other associated anomalies are present (e.g., cardiac anomalies). ^[11]