- 1.
Esophageal surgery in neonates includes the treatment of esophageal atresia, gastroesophageal reflux, congenital esophageal stenosis, esophageal duplication, and vascular rings.
- 2.
Esophageal atresia, with or without tracheoesophageal atresia, is the most common congenital anomaly of the esophagus, occurring in 1 in 3500 live births.
- 3.
The surgical treatment of esophageal atresia has undergone several advances including the introduction of thoracoscopic repair.
- 4.
Management of long-gap esophageal atresia remains challenging even at high-volume centers.
- 5.
Results from recent large, multicenter registries brought into question some aspects of traditional surgical management of esophageal atresia and are moving management toward an evidenced-based approach.
Introduction
Esophageal pathology in the newborn period represents a broad range of disorders that affect feeding, swallowing, and airway protection. These conditions require the multidisciplinary care of neonatologists, pediatric surgeons, aerodigestive specialists, and many others and are just a part of the complex care delivered to infants in modern neonatal intensive care units. A detailed understanding of the surgical considerations of infants with congenital and acquired esophageal pathologies is advantageous to those who are focused on these most fragile patients, because the respiratory and developmental morbidities associated with esophageal pathology can be significant. Herein, we review the principles of surgical management of esophageal pathology in the newborn, including esophageal atresia (EA) and tracheoesophageal fistula (TEF), gastroesophageal reflux disease, and other congenital anomalies, with a focus on the evidence-based clinical approaches and evaluation of outcomes.
EA and TEF
Pathophysiology
Embryology
EA occurs in approximately 1 in 3500 live births and is a congenital anomaly that develops in utero. During normal development, the respiratory and digestive tracts separate into the anterior trachea and the posterior esophagus, a process that commences with the outgrowth of the trachea from the ventral foregut by the fourth week of gestation. , The precise mechanism by which EA/TEF occurs during organogenesis is incompletely understood, but several risk factors have been discovered that increase the odds of EA/TEF. EA occurs more commonly in twins, with a relative risk of EA in twins compared with singleton pregnancies of 2.56 (95% CI, 2.01–3.25). EA is also seen in a number of other congenital associations and genetic syndromes. Up to one in four infants born with EA will have an associated nonrandom anomaly as part of the VACTERL association—a spectrum that includes vertebral, anorectal, cardiac, tracheal, esophageal, renal, and limb anomalies. , Additionally, genetic syndromes occur in 10% of infants with EA and include trisomy (chromosomes 13, 18, or 21) and single-gene disorders (CHARGE syndrome [coloboma, heart defects, atresia of the choanae, retardation of growth and mental development, genital underdevelopment, esophageal atresia], DiGeorge syndrome, Feingold syndrome, Opitz syndrome, and Fanconi anemia).
Anatomy and Classification
A familiarity with the anatomic variations of EA/TEF is critical for the systematic assessment of an infant suspected of having the anomaly, an understanding of the physiologic consequences of uncorrected EA/TEF, and the formulation of a surgical strategy for correction. The most commonly used classification is that described by Gross, but a simple description of the anatomy of each arrangement can be equally helpful in understanding the presenting features and pathophysiology associated with each ( Fig. 86.1 ). Five common anatomic variants are described, in order of most to least frequent: (1) EA with distal TEF—Gross type C, (2) isolated EA with no fistula—Gross type A, (3) TEF with no EA—commonly referred to as “H” type fistula, (4) EA with a proximal TEF—Gross type B, and (5) EA with both proximal and distal TEFs—Gross type D.
The most common conformation, EA with distal TEF, occurs in 86% of cases. In this arrangement, frequently referred to by its Gross classification “type C,” the proximal esophagus ends in a blind pouch in the superior mediastinum, typically at the level of the third to fourth thoracic vertebra. , The fistula occurs between the distal esophagus and the posterior wall of the trachea, usually within centimeters of the carina. This anatomy allows for the passage of air from the trachea into the low-resistance distal esophagus and intraabdominal intestinal tract, and thus intraluminal abdominal gas will be appreciated on plain radiograph. Additionally, because a TEF does exist, there is risk for gastric contamination of the respiratory tract with subsequent pneumonitis.
The next most common configuration occurs far less frequently, in 8% of cases, and involves an isolated EA with no fistula (type A). The absence of a distal fistula will result in a gasless abdomen, which can be seen on radiograph. In contrast to the gap distance in the typical type C defect, the distance between the blind upper and lower ends of the esophagus in type A is relatively far in isolated EA, thereby often precluding the possibility for a primary anastomosis shortly after birth.
The third most common type, TEF with no EA, occurs in only 4% of cases but presents some unique diagnostic challenges. , Although this is frequently referred to as an “H” type fistula, it has also been more accurately described as an “N” type due to the fistula running from the proximal orifice in the trachea to a distal orifice in the esophagus. Although there is no EA, most of these children can eat orally. The clinical presentation of this type is often more subtle and can involve difficulty feeding or, occasionally, excessive flatulence due to the increased passage of gas into the gastrointestinal tract. This condition can go undetected in the newborn period.
Natural History
The abnormal anatomic arrangements that result from EA/TEF produce predictable physiologic patterns that are important to recognize and aid in operative planning. Without surgical repair or a temporizing operation, there is no spontaneous resolution of the pathophysiologic consequences of the enteral system discontinuity and/or fistulous connection between the aerodigestive tracts. Therefore, before surgical correction became a feasible operation, the condition was uniformly fatal. In the modern era, up-front surgical correction is successful in most cases, and when not possible (due to comorbidities, extreme low birth weight, or long-gap atresia), temporizing strategies to manage the fistula and to provide enteric feeding access can be implemented.
Without continuity of the digestive tract, neonates with EA are unable to feed orally and thus will develop oral aversion. Although enteral access can be attained surgically, neonates with uncorrected EA are also unable to handle oral secretions, which increases the risk of recurrent oropharyngeal aspiration. Additionally, abnormal development of the trachea and aspiration of gastric contents through a fistulous tract leads to pneumonitis and respiratory compromise.
Clinical Features
Prenatal Diagnosis
Less than 20% of EA/TEF cases are detected prenatally. The characteristic findings on prenatal ultrasound suggestive of EA/TEF are polyhydramnios, an absent or small stomach bubble, and a “pouch sign” in which a fluid-filled, blind-ending esophagus is seen during fetal swallowing. However, these findings are usually not seen at the 20-week anatomic survey, are nonspecific, and can often be misleading, because there are several other and more common causes of polyhydramnios, and stomach size can vary even in cases of EA due to gastric secretion production. A recent meta-analysis of contemporary prenatal ultrasound estimated the sensitivity of detecting EA/TEF to be only 31.7%. The addition of fetal magnetic resonance imaging (MRI) has somewhat improved the ability to diagnose EA/TEF prenatally. When performed for cases of suspected EA/TEF, fetal MRI has a sensitivity of 94.7% and a specificity of 89.3%.
Clinical Presentation
The clinical presentation of a newborn with EA/TEF is well known to the experienced neonatologist and pediatric surgeon. EA with TEF typically presents just after birth with excessive drooling and the inability to tolerate feeding. It is not uncommon for the first attempt at feeding to result in coughing, choking, or cyanosis. All infants with these signs should be evaluated for EA with an attempt at careful placement of an esophageal feeding tube, which will meet resistance at the level of the atresia—most commonly approximately 10 cm from the lips. A plain chest radiograph will confirm the atresia when the tube is seen to be coiled in the upper esophageal pouch. In the extremely premature neonate, the only other esophageal disorder that should be considered in the differential diagnosis is an iatrogenic upper esophageal tear caused during orogastric tube placement. In these situations, an esophagram using a small volume of radiopaque contrast may be helpful to clarify the diagnosis.
If an abdominal radiograph demonstrates gas in the abdomen, in the presence of EA, it can be assumed that a distal TEF is also present ( Fig. 86.2 ). A concomitant duodenal atresia is present in 2% to 5% of patients, in which abdominal radiograph will show a “double bubble” sign. In contrast, if the abdomen is completely gasless, no such distal fistula is suspected. On physical examination, a scaphoid abdomen raises the suspicion for pure EA with no fistula, whereas a distended abdomen indicates the presence of a distal TEF.
The presentation of TEF without EA (H-type TEF) is not as obvious because the esophagus remains in continuity, which allows for clearance of saliva, the passage of an esophageal tube, and oral feeding. Furthermore, the presence of associated anomalies is less frequent, so suspicion for TEF may be underappreciated. TEF without EA should be considered in infants with coughing and choking during feeding, which occurs due to aspiration through the fistula. Nevertheless, these symptoms are associated with a broad differential, and the diagnosis of TEF without EA is elusive and can be missed in the neonatal period in up to one-third of cases. , If TEF without EA is suspected, it is best diagnosed with a prone pull-back esophagram and/or rigid bronchoscopy , ( Fig. 86.3 ).
Evaluation
Evaluation of Associated Anomalies
Once EA/TEF is diagnosed, a comprehensive evaluation of the associated anatomic and chromosomal anomalies ensues to determine treatment priorities. The most common accompanying anomalies are part of the VACTERL (vertebral, anorectal, cardiac, tracheal, esophageal, renal, limb/laryngeal) association. Therefore a complete physical exam is performed with a special focus on the cardiac (30%–60%), anorectal (7%–12%), and limb (6%–10%) exams.
The most urgent adjunct study is echocardiography to assess for congenital cardiac disease, which is a major driver of mortality. , , The most common cardiac anomalies associated with EA/TEF are atrial septal defect, ventricular septal defect, and tetralogy of Fallot. , In addition to identification of cardiac anomalies that might require urgent treatment, echocardiography can identify anomalies of the upper mediastinal vessels that are important to operative planning. These occur in up to 18% of patients and include a right-sided aortic arch (2%–6%) and an aberrant right-sided subclavian artery (12%). When a vascular anomaly is detected, cross-sectional imaging should be considered to optimize the operative approach.
Additional adjunct studies should be performed in all EA/TEF patients to rule out renal, limb, vertebral, and chromosomal abnormalities. Renal ultrasound will characterize the presence of the kidneys and any irregularities in renal development. Suspected radial limb anomalies on physical exam should be confirmed by plain radiography. Spinal radiography and ultrasound are used to look for vertebral anomalies and a tethered spinal cord, respectively. Any stigmata of chromosomal abnormalities should prompt a genetics consult.
Management
Preoperative Management
The goal of preoperative management of EA/TEF is to maintain cardiorespiratory stability and to provide hydration and nutrition until surgical repair is accomplished. To decrease oropharyngeal aspiration and respiratory tract contamination with gastroesophageal contents, newborns are made NPO (nil per os), and a large-bore oral esophageal sump drainage tube should be placed into the blind-ending esophageal pouch and put to continuous suction. A double lumen Replogle-type tube is best for drainage, and simple feeding catheters should be avoided. The head of the bed is elevated to 45 degrees and acid suppressive therapy is begun. Intravenous hydration is provided, and typically, a central venous catheter is placed for administration of parenteral nutrition because in most cases, it is anticipated that enteral feeding will not begin until 5 to 7 days after surgical repair.
The approach to respiratory management in neonates with a type C EA/TEF is based on avoidance of air flow preferentially through the fistula into the gastrointestinal tract. Excessive air entry into the stomach can cause gastric distension leading to further respiratory failure, an increase in reflux and aspiration through the fistula, and even gastric perforation. Spontaneous respiration is preferred and can be accomplished in most infants, especially those born at term. When mechanical ventilation is necessary, it should be undertaken judiciously and by a team experienced in the advanced respiratory support of neonates with EA/TEF. Also, a pediatric surgical team should be available should any emergent operative intervention be required.
During endotracheal intubation, care must be taken to avoid intubation of the fistula, which can lead to rapid decompensation. Patients with EA/TEF are at an increased risk for laryngeal anomalies, which can result in a challenging airway. The ideal positioning of the endotracheal tube when a TEF is present is to place the tip of the tube just below the level of the fistula, and flexible bronchoscopy can be a valuable tool to confirm the position of the endotracheal tube in relation to the fistula. Once the airway is secured, lower ventilator pressures should be used, and high-frequency oscillator ventilation has been described as an approach to minimize gastric distension.
In routine cases in otherwise healthy newborns, operative repair of a type C EA/TEF can take place within the first 24 to 48 hours of life to minimize aspiration and pulmonary soiling. Perioperative antibiotics are given to cover skin and upper gastrointestinal flora. Finally, EA/TEF repair is a major surgery, and preoperative optimization includes correction of any coagulopathy of the newborn, which is usually through vitamin K administration.
Operative Repair of EA/TEF
The goals of operative repair of any type C EA/TEF are twofold—division of the fistula and establishment of esophageal continuity. Once the airway is secured, rigid bronchoscopy is routinely performed to locate the TEF and to assess for the rare possibility of an additional proximal fistula. The operation is most commonly performed through a right thoracotomy incision. During dissection anterior to the proximal esophagus, care must be taken to avoid a posterior tracheal injury. Once sufficient esophageal length is attained, the two ends are sutured together by a single-layer end-to-end anastomosis. A chest tube is left in the extrapleural space adjacent to the anastomosis to control any potential anastomotic leak.
Traditionally, most surgeons have left a transanastomotic nasogastric feeding tube across the esophageal connection. Transanastomotic tubes have been reported to be used in almost three-fourths of cases in large academic medical centers. The transanastomotic tube has been placed both for early feeding access while the anastomosis is healing and because some have thought the tube improves healing through stenting of the esophagus. However, these theoretical advantages have not been supported by recent studies, and the tube may induce a foreign-body reaction that might have negative implications. Strikingly, in recent studies, transanastomotic tubes were associated with an increased risk of stricture formation. , Therefore the routine use of transanastomotic feeding tubes after TEF repair for EA with distal TEF is no longer recommended. The association between transanastomotic tubes and stricture has been explained through animal models demonstrating an increased rate of stricture with mechanical shearing by a foreign body and increased exposure to gastric acid reflux, which can occur when a tube is placed across the gastroesophageal junction.
Thoracotomy in infancy, even with a muscle-sparing approach, is associated with reported long-term morbidities including muscle weakness, winged scapula, and scoliosis. , Therefore a minimally invasive approach to repair using thoracoscopic surgery has been developed as an alternative to traditional thoracotomy. Additional potential benefits of thoracoscopy for EA/TEF repair include improved visualization of the posterior mediastinum and improved cosmesis. However, thoracoscopic EA/TEF repair is technically challenging, and only between 10% and 20% of EA/TEF repairs in the United States are performed thoracoscopically. When thoracoscopy is the selected approach, outcomes appear to be equivalent to open repair, with no differences in anastomotic leak or stricture rate. , However, there may be significant selection bias when comparing thoracoscopic with open EA/TEF repair.
Management of Long-Gap EA
Long-gap atresia is often defined when the distance between esophageal ends measures at least three vertebral bodies based on preoperative imaging studies. Although the surgical management of most type C EA/TEF neonates is relatively straightforward, management of long-gap EA, usually type A EA, remains a significant challenge. These patients are best managed at a center of excellence with a multidisciplinary care team devoted to the care of these complex patients.
The initial management of long-gap EA consists of (1) feeding gastrostomy placement to allow for enteral feeds, (2) continuous suctioning of the upper esophageal pouch, and (3) serial imaging with contrast to determine gap distance. A baby with pure EA in the absence of a fistula is not at imminent risk of aspiration and pulmonary soiling. Therefore definitive repair can be delayed for 1 to 3 months to allow the gap the opportunity to spontaneously narrow over time. Cervical esophagostomy is strongly discouraged because it will make subsequent attempts at a delayed primary repair more difficult.
Gastrostomy placement in infants with pure EA can be challenging because the stomach is relatively small from disuse, and placement should be strategic to allow for use of the stomach as an esophageal replacement conduit in the future if needed. After a gastrostomy tube is placed, the infant is allowed to feed enterally and grow in the neonatal intensive care unit, with continued suction drainage of the proximal pouch. With bolus gastrostomy feeds, the distal esophageal pouch may grow and lengthen. The proximal pouch may also lengthen over time due to the swallowing reflex with sham feeds. In most cases, the gap will shorten by approximately two vertebral bodies, enabling a delayed primary anastomosis.
Gap distance is assessed with serial gap studies, also referred to as “gapograms” ( Fig. 86.4 ). The initial study is typically obtained once the gastrostomy site heals and is repeated at monthly intervals for up to 3 months. It is most accurate to measure the gap length in terms of vertebral bodies rather than centimeters to account for infant growth and variation in size over time. Primary repair is usually attainable when the gap distance is less than two vertebral bodies.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
