Oesophageal Atresia and/or Tracheoesophageal Fistula

 


Embryology

Smith's theory: The trachea and esophagus initially begin as a single tube. The lateral esophageal grooves are formed as the dorsal esophagus is separated from the ventral trachea. Should the septation process continue distally, esophageal atresia would result.

Grunewald's theory: Elongation of the trachea is rapid in a caudal direction. When there is a fistula producing fixation of esophagus to trachea, the dorsal wall of the esophagus is drawn forward and downward to be incorporated into the trachea. Atresia of the esophagus results because of the fistula.

Bronchogenic theory: The esophagus does not develop at all distally. Rather, a third "bronchus" develops in the primordial lung bud and grows inferiorly to attach to the stomach.
 

VACTERL Association

  • Vertebral anomalies
  • Anal malformations
  • Cardiac malformations
  • Tracheoesophageal fistula
  • Renal deformities
  • Limb deformities (believed to result due to hyperflexion of the embryo)

Figure 11-5. The main varieties of tracheoesophageal fistula.
Figure 11-5. The main varieties of tracheoesophageal fistula. Possible directions of the flow of the contents are indicated by arrows. Esophageal atresia, as illustrated in A, is associated with tracheoesophageal fistula in more than 85% of cases. B, Fistula between the trachea and esophagus. In C, air cannot enter the distal esophagus and stomach. Air can enter the distal esophagus and stomach in D, and the esophageal and gastric contents may enter the trachea and lungs.

Classification (Gross's Anatomical Classification)

  • Type A: Esophageal atresia without tracheoesophageal fistula.
  • Type B: Esophageal atresia with proximal tracheoesophageal fistula.
  • Type C: Esophageal atresia with distal tracheoesophageal fistula (most common type) (85%).
  • Type D: Esophageal atresia with proximal and distal fistula.
  • Type E: Tracheoesophageal fistula without atresia. (Not shown)

Diagnosis

  • One in every 3,000 live births.
  • Hydramnios: Fetus unable to swallow amniotic fluid (may be responsible for early delivery).
  • Choking, coughing and regurgitating with first feed. Excessive salivation. Cyanosis with feeds.
  • Inability to pass feeding tube into the stomach.
  • Contrast studies sometimes used (with caution) in upper part.
  • Abdominal films should be obtained to rule out the occurrence of associated gastrointestinal anomalies.
  • Isolated tracheoesophageal fistula is more difficult to diagnose and may require repeated lateral esophagrams, bronchoscopy and esophagoscopy.

Treatment

  • Evaluate for evidence of associated anomalies, respiratory or cardiac anomalies.
  • Early surgical repair (+ bronchoscopy):
    • Transpleural
    • Extrapleural
  • Complications:
    • Stricture
    • Leak
    • Gastroesophageal reflux
    • Post surgical repair stricture

From:http://nba.uth.tmc.edu/courses/devo2004/lectures/block_3/lally/gastro_3/01_esophageal_atresia.htm