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.
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.
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.
deformities (believed to result due to hyperflexion of the embryo)
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)
- One in
every 3,000 live births.
Fetus unable to swallow amniotic fluid (may be responsible for
coughing and regurgitating with first feed. Excessive salivation.
Cyanosis with feeds.
to pass feeding tube into the stomach.
studies sometimes used (with caution) in upper part.
films should be obtained to rule out the occurrence of associated
tracheoesophageal fistula is more difficult to diagnose and may
require repeated lateral esophagrams, bronchoscopy and
for evidence of associated anomalies, respiratory or cardiac
surgical repair (+ bronchoscopy):
- Post surgical repair stricture