Steven W. Bruch
Presentation
A newborn baby boy, born to a healthy 28-year-old female at 37 weeks’ estimated gestational age with APGAR scores of 8 and 9, had difficulties with his first feed. He coughed and sputtered after the feeding appearing to choke and then almost immediately spit up all of the feeding. There was no bile in the emesis. A nasogastric tube was passed but met resistance. A chest x-ray revealed the tube curled up at the thoracic inlet, a slightly distended stomach, but otherwise a normal abdominal gas pattern.
Differential Diagnosis
Failure to tolerate feeds and an x-ray showing a nasogastric tube coiled in a proximal esophageal pouch with air in the bowel is typical in a baby born with esophageal atresia (EA) and a distal tracheoesophageal fistula (TEF). There are five variations of EA with or without TEF as seen in Figure 1, with the most common being EA with a distal TEF. An iatrogenic esophageal perforation can mimic an EA with difficult passage of a nasogastric tube. These perforations are almost always in the proximal esophagus and heal on their own with intravenous antibiotics, nothing per mouth, and placement of a tube past the perforation into the stomach to help drain the saliva.
FIGURE 1 • The five varieties of EA with and without tracheoesophageal fistulas with their rates of occurrence. (A) EA with a distal TEF. (B) Pure EA. (C) EA with a proximal and a distal tracheoesophageal fistula. (D) EA with a proxi-mal TEF. (E) H-type TEF.
Workup
Preoperative workup attempts to answer three questions: Are there associated anomalies? What side of the chest is the arch of the aorta located? And what is the exact anatomy of the trachea, esophagus, and their connections?
Anomalies associated with EA and TEF include chromosomal anomalies and a sequence of anomalies referred to as the VACTERL sequence that includes vertebral, anorectal, cardiac, tracheal, esophageal, renal, and limb anomalies. A karyotype will look for chromosomal anomalies the most frequent being trisomies 13 and 18, which are lethal, and trisomy 21, Down’s syndrome. The VACTERL anomalies are evaluated with physical exam looking for the anorectal anomalies, usually imperforate anus, plain x-rays for the vertebral and limb anomalies, an abdominal ultrasound for renal anomalies and to look for tethering of the spinal cord, and an echocardiogram for cardiac abnormalities.
The echocardiogram is also used to locate the aortic arch. If the arch is located on the right side, it makes it difficult to complete the esophageal anastomosis over the arch when approached through a right-sided thoracotomy. In that event, a left thoracotomy allows a more tension-free esophageal anastomosis.
The anatomy of the trachea and esophagus can be defined in a number of ways. The initial plain x-ray determines if a distal TEF is present. If there is a gasless abdomen as seen in Figure 2, there is no distal TEF, whereas if there is gas in the bowel, a connection between the trachea and the distal esophagus is present. A proximal fistula can be evaluated with a “pouchogram,” rigid bronchoscopy, or both. A pouchogram depicted in Figure 3 involves placing a small amount of barium in the proximal esophageal pouch to evaluate the size of the pouch and to look for a connection between the proximal esophageal pouch and the membranous portion of the trachea. A small pouch implies that fluid swallowed by the fetus exited the pouch via a proximal fistula, therefore not providing the pressure required to distend the proximal esophageal pouch. Rigid bronchoscopy will allow visualization of the distal fistula, which is usually seen at the carina as shown in Figure 4. A close look should be undertaken for a proximal fistula, which is rare and quite a bit more subtle than the distal fistulas. An H-type fistula often is suspected later than the neonatal period and is diagnosed with an esophagram as seen in Figure 5, and/or rigid bronchoscopy.
FIGURE 2 •The gasless abdomen of pure EA. The proximal pouch is outlined with contrast.
FIGURE 3 • AP (A) and lateral (B) views of a pouchogram revealing no connection between the upper esophageal pouch and the trachea.
FIGURE 4 • Bronchoscopic view of the distal TEF emanating from the carina between the right and the left mainstem bronchi.
FIGURE 5 • Esophogram demonstrating an H-type TEF denoted by the arrow. Contrast placed in the esophagus entered the tracheobronchial tree via the H-type fistula.
Diagnosis and Treatment
With the diagnosis made and the workup completed, the newborn is taken to the operating room for repair of the EA and TEF. In children with EA without a distal TEF, a gastrostomy tube placement with evaluation of the gap length between the two ends of esophagus is the first step in treatment. If the gap length is ≥3 vertebral bodies, repair is delayed. With growth, the gap length may shorten allowing primary repair, or remain “long” leading to the creation of an esophageal spit fistula in the left side of the neck and an eventual esophageal replacement with either a gastric or colon conduit.
Surgical Approach
A right posterolateral thoracotomy is used unless a right-sided aortic arch is identified on echocardiography, when a left posterolateral thoracotomy provides optimal exposure. A muscle-sparing technique minimizes rib cage and spinal abnormalities later in life. The chest is entered through the fourth interspace using a retropleural approach. This allows for more easy retraction of the lung during the case and prevents intrapleural soilage in case of an anastomotic leak post operatively. The azygos vein is identified and divided exposing the connection between the trachea and the distal esophagus. The esophagus will distend with each breath helping identify its location. The fistula is divided as close to the tracheal wall as feasible with Prolene sutures. The proximal pouch is then searched for asking the anesthesiologist to push on the nasogastric tube in the pouch. The proximal esophagus will be located at the thoracic inlet. A suture, used to provide traction, is placed through the esophageal pouch and the nasogastric tube. The proximal pouch is dissected fully as proximal as possible keeping in mind the possibility of coming across a proximal fistula between the pouch and the membranous portion of the trachea. The dissection should avoid opening the membranous tracheal wall by staying on the thick muscular wall of the esophageal pouch. At this point, an assessment of the length of the gap between the two ends of the esophagus should be made. If the two ends can be brought together, an anastomosis is performed. If extra length is required, the distal esophagus may be mobilized. Although the blood supply to the distal esophagus, which is segmental from the descending aorta, is more tenuous than that of the proximal esophagus, which arises from the thyrocervical trunk, the distal esophagus may safely be mobilized if length is required after complete mobilization of the proximal esophagus. Other techniques to gain length include circular myotomies of the proximal pouch and tubularization of the proximal pouch as seen in Figures 6and 7. When adequate length is obtained, an eight-stitch anastomosis is performed with absorbable suture material. The five back row sutures are placed, and a nasogastric tube is placed through the anastomosis and into the stomach. Then, the remaining three anterior sutures are placed to complete the anastomosis as shown in Figure 8. A chest tube is placed and the thoracotomy incision is closed. Recently, thoracoscopic techniques have been developed to complete the repair in a minimally invasive fashion.
FIGURE 6 • Use of a circular esophageal myotomy on the upper pouch to gain length and close the esophagus primarily.
FIGURE 7 • Use of an anterior muscle flap of the upper pouch to gain length and close the esophagus primarily. (Reprinted from Gough MH. Esophageal atresia—Use of an anterior flap in the difficult anastomosis. J Pediatr Surg. 1980;15(3):310–311, with permission from Elsevier.)
FIGURE 8 • Esophageal anastomosis. A: Posterior sutures placed. B: Nasogastric tube is passed and anterior sutures complete the anastomosis.
Special Intraoperative Considerations
Babies born with pure EA without a connection between the trachea and the distal esophagus present unique problems. The gap between the two ends of the atretic esophagus is often too long to bridge in the neonatal period. The first operative step in a pure EA is the placement of a gastrostomy tube to gain access to the stomach for enteral feeds. The stomach in these babies is very small making the placement technically challenging. When the gastrostomy tube is placed, an estimate of the gap length can be obtained by placing a tube in the upper pouch and a neonatal endoscope in the distal esophagus via the gastrostomy site and looking at the gap distance with fluoroscopy. If the gap is within two vertebral bodies, a primary repair may be attempted. Most of the time, this gap will be too long to close, and the baby will be nursed with a Replogle tube in the proximal pouch, the head of the bed elevated 45°, and using the G-tube for feedings. Evaluation of the gap length should then be carried out every 4 to 6 weeks. Most agree that if the gap is not close enough to attempt repair by 3 months of age, then it is time to think about an esophageal replacement. This would include creating a spit fistula in the left neck in preparation for a gastric transposition or a colon conduit. The spit fistula allows sham feeds in these babies while they await their replacement operation. An option to consider prior to going to replacement of the esophagus is the “Foker” technique. This technique uses tension on the esophageal ends over time to lengthen the proximal and distal esophageal remnants. Multiple sutures with pledgets are placed on the proximal and distal esophageal ends. These sutures are then brought out the back of the baby (the lower pouch sutures out the upper back, and the upper pouch sutures out the lower back) where they are placed on traction and shortened a small incremental amount each day until the ends are close enough to allow primary anastomosis as shown in Figure 9.
FIGURE 9 • The “Foker” technique. A: Sutures placed in upper pouch and distal esophagus. Metal clips are placed to track the position of the esophageal ends using plain x-ray. B: Sutures are brought out the back and traction is used over time to lengthen the two segments of the esophagus.
On occasion, babies with EA are born with premature lungs and ventilation becomes difficult. The premature lungs require increased peak inspiratory pressures to adequately ventilate. This may result in a large portion of each mechanical breath going down the fistula rather than to the lungs because the air will travel the path of least resistance. This can be a difficult problem to manage. Attempts can be made to place the tip of the endotracheal tube past the fistula opening. This can rarely be sustained as a solution because of the mobility of the endotracheal tube, and the close relationship of the TEF and the carina. There are several other options to control this problem. Placement of a Fogarty catheter that is inflated into the fistula opening with rigid bronchoscopy followed by reintubation often temporizes the situation. However, the Fogarty often inadvertently slips out of position causing this method to fail. Another option is to place a gastrostomy tube and put the end of the tube to underwater seal, thus increasing the resistance of the fistula tract and allowing more air into the lungs. At the time of gastrostomy tube placement, a Rumel tourniquet may be placed around the gastroesophageal junction and brought out the upper abdomen. This can be used to intermittently occlude the esophagus again forcing air into the mainstem bronchi rather than down the fistula. A more long-term solution is to divide the fistula through a right posterolateral thoracotomy. This should improve the respiratory status of the baby. If the anesthesiologist can then easily ventilate and oxygenate, the definitive repair can be done. If the baby does not improve after the fistula is divided, the distal esophagus should be stretched cranially and tacked to the prevertebral fascia with permanent sutures and the chest closed. This allows a definitive repair later when the baby has grown and the respiratory issues have resolved.
Postoperative Management
In the postoperative period, the baby is nursed with the head of the bed elevated and meticulous care is taken to keep the oropharynx suctioned of saliva to prevent aspiration and pneumonia. Some surgeons will feed enterally through the tube across the anastomosis into the stomach. A contrast study of the esophagus is performed about 1 week after the operation to look for a leak. If no leak is present, the tube is removed, feeds are begun, and the chest tube is removed if no formula or saliva is seen draining. If there is a leak, large or small, the baby remains on antibiotics, the chest tube remains in place, and the study is repeated 1 week later until no leak is seen. These postoperative leaks seal with time. In addition to a leak, four more complications should be anticipated: stricture formation, gastroesophageal reflux, tracheomalacia, and recurrence of the TEF.
Stricture formation is common occurring in up to 40% of repairs. The stricture is almost always at the anastomosis although rarely a primary cartilaginous esophageal stricture may be present in the distal esophagus in association with a TEF. Strictures are initially dilated with balloon dilators, or tapered bougie dilators that can be used over a guide wire (Savory dilators) or passed blindly (Maloney dilators). If a gastrostomy tube is present, Tucker dilators may be attached to a string that traverses the stricture from the mouth to the stomach and pulled through the stricture. A child with a stricture that fails to stay open after serial dilation should be evaluated for gastroesophageal reflux disease, as the stricture will not resolve until the reflux is adequately managed.
Gastroesophageal reflux occurs very commonly in this patient population, up to 70% of the time. Reflux is initially managed medically with a proton pump inhibitor with or without the addition of an H2 blocker. If medical management fails, a fundoplication may be necessary. Care must be taken when fashioning a fundoplication in these children. The distal portion of the esophagus in TEF patients does not peristalse well and a fundoplication can lead to difficulties with dysphasia. Most pediatric surgeons will use a “floppy” Nissen fundoplication in these patients, although some prefer a partial wrap. Occasionally, these children will have a relatively short esophagus due to the initial repair and require a Collis-Nissen fundoplication to gain adequate length for a proper fundoplication.
Tracheomalacia can mimic gastroesophageal reflux disease in this patient population and occurs in up to 20% of babies born with TEF. Tracheomalacia occurs due to weakening of the tracheal cartilage resulting in “ fishmouthing” of the trachea with expiration as seen on bronchoscopic view in Figure 10. Rigid bronchoscopy with the baby spontaneously breathing will diagnose tracheomalacia. Most babies will grow out of the malacia, but those with severe tracheomalacia require an aortopexy to stent open the trachea as seen in Figure 11.
FIGURE 10 • Bronchoscopic view of tracheomalacia. A: Open trachea during inspiration. B: The “fish mouth” collapse of the trachea during expiration.
FIGURE 11 • Aortopexy involves suturing the adventitia of the aorta to the sternum. This stents open the trachea in the babies with severe tracheomalacia.
Recurrent tracheoesophageal fistulas occur in up to 10% of repairs. If suspected in children with respiratory issues around feeds or frequent pneumonias, it can be diagnosed with an esophagram or using a combination of rigid bronchoscopy and esophagoscopy. The best contrast study to identify a recurrence is a prone pullback esophagram where the study is done with the child lying prone allowing gravity to reveal the connection between the trachea and the esophagus. The use of rigid bronchoscopy and esophagoscopy will sometimes identify a recurrent fistula, but they are often difficult to pick up. In those difficult cases, placing methylene blue into the trachea and ventilating allow the dye to pass through the fistula if present into the esophagus where the blue dye can be seen with esophagoscopy. A recurrent fistula can be approached initially endoscopically. The fistula is identified; the mucosa is removed as best as possible mechanically or with argon beam coagulation, and then an adhesive is placed bronchoscopically to occlude the fistula. If this fails an open procedure is required to separate the trachea and esophagus, repair the fistula, and place viable tissue between the suture lines. Usually, a flap of pericardium works well to prevent future recurrences.
Survival is excellent with a near-term infant without cardiac anomalies. However, prematurity and the presence of a significant cardiac defect reduce the expected survival. Infants weighing >1,500 g at birth without major congenital cardiac anomalies have a 97% survival rate. If the infant is either born <1,500 g or has a major cardiac anomaly, the survival rate decreases to 59%. Infants who weigh <1,500 g at birth and have a major cardiac abnormality have only a 22% chance of survival.
Case Conclusion
On the second day of life, the baby underwent successful repair of the EA and TEF. The contrast study at 1 week showed no leak. Feeds were initiated and tolerated well, and he was discharged home. During the transition from formula to baby food, he developed some vomiting and dysphasia. A stricture was identified at the area of the anastomosis that underwent serial dilation and remained open. Other than having a “hot dog” that was underchewed get caught at the anastomotic site at age 3 requiring upper endoscopy and retrieval, he has done well and is taking all of his nutrition by mouth and thriving.
TAKE HOME POINTS
· EA and/or TEF is identified at birth with emesis and failure to pass a nasogastric tube.
· Plain film confirms EA with the tube in the proximal pouch and presence of a distal TEF when there is air seen in the abdomen.
· Evaluation involves excluding associated anomalies including chromosomal and VACTERL anomalies, identifying the location of the aortic arch, and delineating the anatomy of the trachea, the esophagus, and their connections.
· Repair involves a right muscle-sparing posterolateral thoracotomy using a retropleural approach.
· Identification of the fistula and creation of an esophageal anastomosis with minimal tension provide the technical challenge.
· The anastomosis is studied at 1 week and allowed to heal on its own if a leak is identified. The leak should be retropleural and drained adequately with the chest tube.
· Postoperative complications include anastomotic leaks, strictures, gastroesophageal reflux, tracheomalacia, and recurrent TEFs.
SUGGESTED READINGS
Bruch SW, Hirschl RB, Coran AG. The diagnosis and management of recurrent tracheoesophageal fistulas. J Pediatr Surg. 2010;45:337–340.
Harmon CM, Coran AG. Congenital anomalies of the esophagus. In: Grosfeld JL, O΄Neil JA Jr, Coran AG, et al., eds. Pediatric Surgery. 6th ed. Philadelphia, PA: Mosby Elsevier, 2006:1051–1081.
MacKinlay GA. Esophageal atresia surgery in the 21st century. Semin Pediatr Surg. 2009;18:20–22.
Spitz L, Bax NM. Esophageal atresia with and without tracheoesophageal fistula. In: Spitz L, Coran AG, eds. Operative Pediatric Surgery. 6th ed. London, UK: Hodder Arnold, 2006:109–120.