Pediatric surgery 66 Tracheoesophageal fistula

During the fourth week of gestation, the esophagotracheal diverticulum of the foregut fails to divide completely to form the esophagus and trachea.

• Vertebral
• Anorectal
• Cardiac
• Tracheal
• Esophageal
• Renal, and
• Limb

In the most common type (C lesion) of proximal esophageal atresia with distal TEF, the proximal blind pouch ends approximately the distance of one or two vertebral bodies from the distal TEF

• Infant with excessive salivation along with coughing or choking experienced at the first oral feeding. 
• Maternal history of polyhydramnios
• In an infant with proximal esophageal atresia with distal TEF, acute gastric distention may occur as a result of air entering the distal esophagus and stomach with each inspired breath.
• The clinical presentation of isolated TEF without esophageal atresia may be subtle, often beyond the newborn period. In general, these infants experience choking and coughing associated with feedings

The inability to pass a nasogastric tube into the stomach is a cardinal feature for the diagnosis of esophageal atresia. If gas is present below the diaphragm, an associated TEF is confirmed. Conversely, the inability to pass a nasogastric tube in an infant with absent radiographic evidence of air in the GI tract is virtually diagnostic of an isolated esophageal atresia.

• A Replogle tube is a medical device used in the treatment of babies with oesophageal atresia. It is a double-lumen tube which is inserted through the baby's nostril into the blind-ending oesophageal pouch and used to drain saliva.
• This avoids secretions overflowing into the trachea (windpipe) and causing problems such as aspiration pneumonia.
• Replogle tubes are flushed regularly with saline to help remove secretions

• Decompression of the proximal esophageal pouch with a sump tube (e.g., Replogle tube) placed on continuous suction.
• The infant is positioned in an upright prone position to minimize GER and to prevent aspiration.
• Broad-spectrum IV antibiotic coverage is started empirically.
• Routine endotracheal intubation is avoided because positive pressure ventilation may be inadequate to inflate the lungs as air is directed into the TEF through the path of least resistance.
• Gastrostomy to decompress the distended stomach should be avoided because it may abruptly worsen the ability to ventilate the patient. In these circumstances, manipulation of the endotracheal tube advanced distal to the TEF (e.g., right mainstem intubation) may minimize the leak and permit adequate ventilation. The placement of an occlusive balloon (Fogarty) catheter into the fistula through a rigid bronchoscope may also be useful.
• As a last resort, emergent thoracotomy with ligation of the fistula alone may be required.

• A right thoracotomy is performed for the operative repair in patients with a normal left-sided aortic arch. However, for infants with a right-sided arch, a left thoracotomy would be preferred.
• Open thoracotomy with an extrapleural dissection.
• After exposure of the posterior mediastinum, the azygos vein is divided to reveal the underlying TEF.
• The TEF is dissected circumferentially, and its attachment to the membranous portion of trachea is taken down.
• The tracheal opening is approximated with interrupted nonabsorbable sutures.
• The proximal esophageal pouch is then mobilized as high as possible to facilitate a tension-free esophageal anastomosis.
• The blood supply to the upper esophageal pouch is generally robust from arteries derived from the thyrocervical trunk.
• However, the lower esophageal vasculature is more tenuous and segmental, originating from intercostal vessels. As such, extensive mobilization of the lower esophagus should be avoided to prevent ischemia.