While minimally invasive techniques have been used to alleviate esophageal symptoms, such as thoracoscopic release of vascular rings causing esophageal obstruction or laparoscopic fundoplication for gastroesophageal reflux disease (GERD), this chapter focuses on minimally invasive methods for direct surgical repair of congenital esophageal anomalies: esophageal atresia (EA) with or without tracheoesophageal fistula (TEF) and foregut duplication cysts.

As described in the previous chapter, the advent of successful surgical intervention for EA in the 1930s and 1940s was a hallmark event for pediatric surgery, changing a universally fatal anomaly into one that could be surgically repaired with an expectation for long-term success. With the development of minimally invasive techniques and the rapid advance of both supporting technology and surgical skill and experience, thoracoscopic approaches to esophageal repair have been proposed. Since the first report of a primary thoracoscopic repair of congenital EA in 1999 and EA with TEF in 2000, the use of this technique has gained traction and now is being performed at many, if not most, centers with advanced pediatric surgery capabilities.¹

The novelty of reports describing the thoracoscopic technique for repair of EA/TEF, not to mention that the operation is performed on some of our most fragile patients, is likely responsible for the delay in widespread acceptance of this approach. It ranks among the most technically demanding of pediatric minimally invasive procedures and requires advanced thoracoscopic surgical skill.^1,2 Multiple centers, however, now have reported their experience with this approach to treating EA with or without TEF, and as experience and longer-term outcomes accumulate, its place in the field of pediatric surgery will be determined.

On the other hand, the excision of foregut duplication cysts, specifically esophageal duplication cysts, is particularly suited to minimally invasive techniques, and this procedure now is routinely performed thoracoscopically. In contrast to newborns with EA in all its various forms, patients with foregut duplication cysts generally are older, more healthy, and rarely present with comorbid conditions. The absence of comorbidity perhaps is most responsible for the ready acceptance of the thoracoscopic approach to excising foregut duplication cysts.

EA occurs in 1 in 5000 births. It can develop in many forms, with the most common being the “Type C” atresia, comprised of EA with a distal TEF (see Fig. 52-1). The second most common scenario is EA without TEF, so-called pure EA. Although other forms exist, these two forms are most amenable to the thoracoscopic approach to esophageal repair. Since the first reporting of thoracoscopic repair of pure EA in 1999³ and EA with distal TEF in 2000,⁴ this approach has become increasingly used, and multi-institutional experiences have been reported.¹

General Principles

As with any intestinal anastomosis, the key surgical principle of the thoracoscopic esophageal repair in EA is to perform the procedure with the same high standards as one would follow when performing open surgery. Paramount in this procedure is healthy tissue, placed together with minimal tension. Some technical principles are detailed below, but are highlighted by the need to handle tissue gently and to incorporate sturdy, full-thickness bites including mucosa into the anastomosis without creating undue tension. As with all minimally invasive techniques, ergonomics and surgeon comfort during the procedure are important to prevent fatigue and allow for fine, delicate movements in the dissection of fragile structures. In addition, although we tend to use intracorporeal knot-tying techniques, extracorporeal techniques using a knot pusher are also well described. Finally, although the surgical techniques may be modified, it is paramount that the surgeon not compromise the quality of the operation to achieve a successful minimally invasive procedure.

The key clinical characteristic that defines thoracoscopic surgery, in antithesis to its open counterpart, is the significantly reduced morbidity related to the incision(s). In the immediate postoperative period, the drastically reduced pain associated with thoracoscopic surgery allows for faster recovery and decreased pulmonary complications in children who may already be at risk for other conditions such as congenital cardiac disease (see below). In addition, patients, especially newborns, are at particular risk for sequelae of open thoracotomy, including musculoskeletal deformities such as “winged” scapula, muscular atrophy with resultant asymmetry, and/or scoliosis.¹

Timing of surgery depends on the patient’s underlying diagnosis (pure EA vs. EA/TEF) and their stability. Pure EA patients can undergo thoracoscopic repair in a delayed fashion, after initial tube gastrostomy and a period of growth on enteral nutrition. Patients with EA/TEF are generally repaired within the first 24 hours of life assuming appropriate size, hemodynamic stability, and the absence of more pressing concomitant congenital defects.

Preoperative Assessment and Patient Selection

Since the various forms of EA can all be a component of the VACTERL (Vertebral anomalies, Anorectal anomalies, Cardiac defects, Tracheo-Esophageal anomalies, Renal anomalies, Limb defects) association, appropriate screening tests should be performed on all patients found to have EA. These include echocardiogram, spine ultrasound and plain films, and renal ultrasound. Chief among these, and the only one necessary prior to operative intervention for EA/TEF, is the echocardiogram. This allows for identification of intracardiac defects, such as ventricular septal defects or tetralogy of Fallot, and for identification of a potential right-sided aortic arch. In most cases, the surgical approach for repair of EA/TEF is through the right chest. A right-sided aortic arch, however, will prompt most surgeons to change to the left chest. Another common association involving EA is the cleverly but somewhat incompletely named CHARGE syndrome (Coloboma, Heart defects, choanal Atresia, Retardation, Genital hypoplasia, Ear abnormalities). This diagnosis is often made postoperatively, and may affect long-term outcomes.

While hemodynamically unstable patients and very premature or growth restricted newborns (<1500 g) should likely not undergo thoracoscopic repair of EA/TEF, there are other relative contraindications. These include significant congenital heart disease and smaller infants (less than 2.5 kg). One additional feature which should be assessed is the expectation of relative “gap” between the proximal esophageal pouch and the fistula in TEF or the distal pouch in pure EA. Plain films can help determine the location of the proximal pouch, with its coiled nasogastric tube, and obviously, the presence of a distal fistula based on the presence of bowel gas. Meanwhile, bronchoscopic evaluation can assess the level of the fistula (e.g., location relative to the carina). In cases of pure EA, most patients receive a gastrostomy at birth followed by delayed esophageal repair. In these cases, a preoperative gap assessment can be obtained by placing a radiopaque instrument such as a Bakes dilator via the gastrostomy and transorally, and obtaining fluoroscopic imaging while placing moderate pressure on the dilators. This technique can also be used intraoperatively for easy identification of the esophageal ends.

Each individual patient’s qualifications for a thoracoscopic approach must be assessed using a combination of these multiple variables. As surgeons (and anesthesiologists) gain more experience and confidence, these boundaries will continue to be tested.^1,5

Technique

Evaluation of the Fistula

We prefer to perform rigid bronchoscopy on all children with suspected EA (see Fig. 52-1), to identify and locate the TEF and also to potentially control it with the use of a balloon-tipped catheter which can be lodged within the proximal fistula and allow for the safer administration of positive-pressure ventilation during the initial stages of anesthesia prior to operative control of the fistula. While this is our chosen technique, not all surgeons perform this step.

Rigid bronchoscopy requires cervical extension in the supine position and the gentle use of an appropriately sized rigid ventilating bronchoscope. Important findings to note should include the assessment of vocal cord function for documentation prior to potential surgery on and around the vagus nerves, assessment for location of the distal fistula, a thorough and methodical evaluation of the posterior membranous trachea to rule out the possibility of multiple TEFs, and the assessment of tracheal stability with the presence or absence of significant tracheobronchomalacia. We then place a Fogarty-type balloon catheter transorally and bronchoscopically direct it into the fistula, inflating the balloon just inside the fistula itself. At the conclusion of bronchoscopy, the patient is orotracheally intubated with the goals of maintaining spontaneous ventilation if possible and avoiding intubation of the fistula which could result in disastrous decompensation. All of these steps are similar for both the open and thoracoscopic techniques.

Anesthetic Considerations and Lung Isolation

The anesthetic technique employed and full two-way communication between the anesthesia and surgery teams are essential to the successful completion of a thoracoscopic procedure in a neonate.¹ The team must be efficient to limit anesthetic time, limit time on positive-pressure ventilation prior to fistula control and maximize the amount of work accomplished during (essentially) single-lung ventilation.

Neonates with pure EA or EA/TEF typically undergo inhalational induction followed by bronchoscopy and balloon control of the fistula. Appropriate IV access is then obtained, typically in the form of 2 to 3 peripheral intravenous catheters and an arterial line for both monitoring of blood pressure and access to obtain blood for laboratory measurements. Transfusion intraoperatively is generally not warranted, and most patients are provided with hourly maintenance isotonic solution as well as 20 to 40 mL/kg of intravenous fluid boluses. Patients have safely been maintained on neuromuscular blockade without significant risk of gastric overdistention, even without preoperative balloon control of the fistula.⁶ Orotracheal intubation usually suffices, though some practitioners will attempt blind or fiberoptic-guided left mainstem intubation. Adequate lung deflation can be achieved by gentle carbon dioxide (CO₂) insufflation using a low flow (1 L/min) and low pressures (4–5 mm Hg).⁵

One key physiologic point is the expected immediate decompensation upon entry into the chest, when the patient is subjected, essentially, to single-lung ventilation. The anesthesia and surgery teams should expect relative hypoxia and hypercarbia, which are usually transient and recover within minutes as intrinsic physiologic mechanisms compensate for the loss of ventilation in the lung on the operative side and thus recover more normal matching of ventilation and perfusion. The frequent evaluation of blood gas measurements will allow for monitoring of this trend. In addition, should the patient not tolerate CO₂ insufflation or lung retraction, both of these may be reversed instantaneously by the surgeons to allow the anesthesiologist to recruit the lung and improve the patient’s status. Ultimately, the free-flowing discussion between the surgeons and anesthesiologists allows for ongoing decision-making regarding proceeding with thoracoscopic repair or converting to an open approach.

Positioning of Patient and Port Placement

Following bronchoscopy and anesthetic preparation, most surgeons prefer a modified prone position (see Fig. 52-2), with the patient’s right chest elevated 45 degrees. This positioning allows the lung and anterior mediastinal structures to fall anteriorly with gravity retraction, thus giving the surgeon excellent exposure to the posterior mediastinum, airway, and esophagus.

With this positioning, the surgeon and assistant stand on the anterior side of the patient, while the monitor is placed at eye level on the posterior side of the patient alongside the scrub nurse.

Three access sites are necessary for the procedure. An initial camera port (generally 4 mm) is placed just inferoposterior to the scapula, usually coinciding with the fifth intercostal space. We use a cut-down type approach, making an appropriate skin incision followed by blunt dissection above the rib using a straight Jacobson dissector. Lung ventilation is held when the pleura is encountered and the pleural space is entered bluntly. The chest wall defect is dilated to the appropriate size and the 4-mm trocar inserted. We use metal trocars fitted with a sleeve (a cut portion of an 18Fr red rubber catheter), which is sewn to the skin to prevent trocar migration.