Tracheoesophageal Fistula
Tracheoesophageal Fistulas can be a serious and life threatening congenital abnormalities in a newborn. It results from the failure of the tracheal bud to develop normally from the primitive foregut during embryogenesis. There are various ways that the esophagus and trachea can be associated in TEFs. There are 5 most common presentations and are named Types A through E.
Type A is esophageal atresia without a tracheoesophageal fistula. This is the most ideal situation for an Anesthesiologist, because there is no connection between the airway and the enteric system. This accounts for around 8% of TEFs.
Type B is an esophageal atresia with a proximal tracheoesophageal fistula. This is an obvious concern for aspiration when feeding a new born since the only outlet from the esophagus is the trachea. This accounts for 1% of TEFs.
Type C is the most common and is an esophageal atresia with a distal tracheoesophageal. In this scenario, the gastric inlet usually arises in the posterior aspect of the trachea. Is it the path of least resistance and must be considered when having difficulties with ventilating a patient. If the patient develops a major leak, it is possible that your ETT could have migrated around or into the fistula in a way that some of your positive pressure ventilation is now insufflating the stomach. This type accounts for around 84% of TEFs.
Type D is a proximal and distal tracheoesophageal fistula with esophageal atresia. This occurs in around 3% of TEFs.
And finally, Type E is an “H-shape” TEF, with a tracheoesophageal fistula that connects a continuous esophagus leading into a stomach with the trachea. This accounts for 4% of TEFs.
The diagnosis can be suspected in prenatally in a scenario of polyhydramnios. It is typically diagnosed at birth with newborns who have excessive drooling, cyanotic episodes, coughing relieved by suction, or the inability to pass a gastric tube. A chest X-ray showing a nasal or oral gastic tube curling in the esophageal stump can confirm the diagnosis.
TEFs can be associated with other congenital abnormalities. These fall into the umbrella of “VACTERL”. This stands for:
-Vertebral anomalies
-Anal Atresia
-Cardiac Defects
-Tracheoesophageal fistulas
-Esophageal atresia
-Renal abnormalities
-Limb defects
In the preoperative time, a full work up would include a chest X-ray, a transthoracic echocardiogram, and labs evaluating electrolytes, pH balance, and hemoglobin levels. Commonly, these patients will benefit from humidified supplemental oxygen via nasal cannula. Continuous suction is applied to the esophageal stump to prevent aspiration.
Intraoperatively, your biggest concerns involve the airway. The greatest concern would be to intubate the TEF and create a bigger defect while also insufflating the stomach. Ideally, you can keep the patient breathing spontaneously with little positive pressure support. An endotracheal tub can be placed under bronchoscopic guidance to avoid the TEF or purposely bypass it. After the TEF has been ligated, it is generally safe to switch to a mode of ventilation that involves more positive pressure.
Postoperatively, these patients will stay intubate to allow for adequate recovery from their operation, especially around the airway. Unfortunately, these patients have potential to develop life long sequelae from this anatomical anomaly such as tracheomalacia, gastroesophageal reflux, esophageal strictures, and tracheal diverticulum.
