Pyloric Stenosis

Hypertrophic pyloric stenosis occurs in 1.5 to 4 in 1000 live births, and more recent population-based studies suggest the incidence is decreasing over time. It remains a common cause of neonatal emesis and typically presents in the third to fifth week of life. The emesis is typically nonbilious and projectile, although some jaundiced infants may have emesis that has bilious appearance. Hypertrophic pyloric stenosis (HPS) occurs more frequently in male newborns, although providers should be aware that a patient whose mother had pyloric stenosis as an infant has a fourfold incidence of HPS. The precise etiology of the hypertrophied pylorus is unclear, but what was once thought to be an inherently congenital problem is now understood to be an acquired condition. The causes of pyloric stenosis are likely multifactorial, including both genetic and environmental causes. Caretakers often describe projectile nonbilious vomiting and infants present with dehydration and electrolyte imbalances. Physical exam may reveal a sunken fontanelle, lethargy, visible intestinal peristalsis, and in some infants a palpable “olive.” The “olive” is frequently appreciated by experienced examiners. A nasogastric tube is sometimes necessary to decompress the stomach while the hungry child is calmed by being allowed to drink glucose water, thereby allowing an exam which reveals the presence of an “olive.” The exam is best performed by standing to the right of the child, placing the left hand behind the lower back, and palpating just to the left of the midline with the right hand. The primary physiologic disturbance is hypokalemic hypochloremic metabolic alkalosis, which occurs due to the gastric losses from unremitting emesis. Evaluation should include a renal function panel and imaging. At centers where immediate ultrasound is not available and an “olive” is not palpated, an upper gastrointestinal (UGI) study may be obtained to delineate the obstruction and hypertrophied pylorus. Although exact size criteria vary by institution, it is commonly accepted that muscle wall thickness greater than 3 mm and length greater than 14 mm is abnormal in infants under 30 days old (Fig. 9-1). Infants who are diagnosed with pyloric stenosis must be adequately resuscitated before proceeding to the operating room for pyloromyotomy. The anesthetic risk is heightened when the patient’s bicarbonate level is 30 or greater, as the body attempts to compensate for the metabolic alkalosis with respiratory acidosis, which is accomplished with decreased respiratory drive or hypoventilation. Resuscitation goals should include correcting the metabolic alkalosis and additional electrolyte disturbances such as hypokalemia. Infants should be voiding adequately as a marker of resuscitation as well prior to the operating room. The surgical treatment of HPS is a pyloromyotomy performed laparoscopically or open. The pylorus is incised longitudinally so as to divide the hypertrophic fibers, but avoiding perforation of the mucosa. The hypertrophied wall is then spread until the entire length of the pylorus allows for bulging of the mucosa from the circular muscle fiber of the stomach to just proximal to the duodenum (Fig. 9-2). The risk for perforation is highest at the duodenal end of the pyloromyotomy, and standard teaching suggests that ongoing feeding intolerance following operation is associated with inadequate proximal pyloromyotomy. Inspection of the mucosa can detect bile if a perforation occurred, and some surgeons will also test the pyloromyotomy with insufflation of the stomach while clamping the duodenum distally. If a perforation is identified, the opening should be closed by approximating the mucosa to the seromuscular edge. Patients often do well postoperatively and are best fed ad lib, or on a fast feeding protocol to reach goal in order to allow for discharge home. Many patients have emesis postoperatively due to edema of the pylorus after manipulation, and parents should be prepared for this expected outcome. Postoperative ultrasound and UGI will demarcate persistent pyloric stenosis even in the setting of adequate pyloromyotomy. Thus, in most cases, watchful waiting is the best course of action with postoperative feeding intolerance. If a perforation has occurred intraoperatively, patients are left with a nasogastric tube and a UGI is performed postoperatively with feeding advancement once a negative study is obtained.

Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is the most common surgical emergency in the neonate and can have lifelong morbidity for affected newborns. NEC is an acquired disease mostly of extremely low birth weight infants (<1000 g). Other risk factors include patent ductus arteriosus treated with indomethacin and enteral feeding with formula. Extensive research has demonstrated the relationship of inflammatory factors, bacterial insults, immune alterations, and environmental genetic roles that may give rise to the mucosal insult in NEC. Providers should be aware of the clinical presentation of an infant with NEC including blood in the stool, bilious emesis, abdominal distention, and abdominal wall discoloration (Fig. 9-3). Neonates may also present with hemodynamic instability, respiratory failure, apnea, bradycardia, neutropenia, leukocytosis, thrombocytopenia, and metabolic acidosis. Plain film radiographs may reveal dilated intestinal loops, bowel wall thickening, pneumatosis intestinalis, portal venous gas, and free peritoneal air. Ultrasound may demonstrate similar findings.

The majority of infants are treated with medical management including discontinuation of enteral feeding, nasogastric decompression, resuscitation, correction of electrolyte abnormalities, and antibiotic initiation. Indications for operative treatment include decline in hemodynamic stability, worsening physical exam, or pneumoperitoneum. The objective in operative treatment is to diagnose the source of sepsis and resect necrotic bowel, and may include a second-look operation in order to limit bowel resection (Fig. 9-4). The patient may be left with one or multiple enterostomies. In unstable low birth weight infants, a drain may be placed in the right lower quadrant in lieu of a formal operation. Most neonates will physiologically improve following drain placement. However, some may go on to decline clinically, and in this case a formal exploration is indicated. Postop care should focus on stabilizing the patient and providing parenteral nutrition, with the plan to close the enterostomy at 6 to 8 weeks after the initial resection. Contrast study is utilized to evaluate for distal points of obstruction since it is common for strictures to form in NEC despite an initial grossly normal appearance of the distal bowel.

Short Bowel Syndrome

Short bowel syndrome (SBS) is a condition in which an impaired or limited length of intestine reduces the absorption of nutrients from enteral sources. SBS can occur due to loss of bowel length in the setting of NEC, midgut volvulus, gastroschisis, and with bowel dysfunction such as with motility disorders. The actual length may vary in those pediatric patients affected by SBS, and is impacted positively by the presence of the ileocecal valve as well as a functional colon. Patients with SBS are dependent on total parenteral nutrition (TPN) and may eventually tolerate feeds entirely via an enteral route. The ability to tolerate enteral feeds is dependent on the proportion of small bowel remaining when compared to that expected. Bowel lengthening procedures such as the serial transverse enteroplasty (STEP) and Bianchi procedures depend on the fact that the bowel dilates in the setting of SBS. Such bowel lengthening procedures, along with the development of optimal medical management–associated emergence of centers with SBS programs have been shown to enhance survival in patients with SBS. When necessary, small bowel transplantation, sometimes with liver transplantation, is an option, with an improving 5-year survival in patients with refractory SBS and/or liver failure.

Severe Reflux/Gastrointestinal Reflux Disease

Gastrointestinal reflux disease (GERD) is a relatively common diagnosis in pediatric patients, and as many as 7% of children and infants are diagnosed with GERD. Infants present to the pediatrician with symptoms of reflux including emesis, retching, back arching, and sometimes more severe symptoms such as apparent life-threatening events (ALTE). Many infants and children experience physiologic reflux, which is not considered pathologic. However, if reflux interferes with adequate nutrition and growth or causes aspiration, esophagitis, or hospitalization, medical intervention should be initiated. Medical treatment may not be effective for all infants and children with GERD, and surgical intervention is considered for these patients. It is not entirely understood why some otherwise normal children develop pathological GERD. Children with esophageal atresia (EA), congenital heart defects, and neurological impairment experience an increased incidence of GERD. The Nissen fundoplication is indicated in children with failed medical management of GERD and who are at risk for complications of reflux if left untreated. The fundoplication is performed laparoscopically or open, and a 360-degree wrap is typically performed. However, in some cases where the esophagus is dysfunctional (such as with EA), or where the patient’s stomach may be small or tubular in shape, a partial wrap, such as a Thal wrap, may be considered. Outcomes favor surgical intervention over long-term medical management. However, the evidence is limited to retrospective data without long-term outcomes. It should be recognized that many children, especially <1 year of age, may simply grow out of their reflux and may not need fundoplication.

Gastroschisis

Gastroschisis is an abdominal wall defect that occurs in the developing embryo and is thought to be a failure of the lateral folds to completely approximate. It affects approximately 5 in 10,000 infants and is associated with maternal factors such as low socioeconomic status, use of tobacco, low maternal age, environmental exposures such as solvents, colorants, and medications such as cyclooxygenase inhibitors and decongestants. Prenatal diagnosis is made via in utero ultrasound. At one time the thought was that Cesarean section may be indicated to prevent injury to the exposed bowel. However, there are no data to support either early vaginal or Cesarean section delivery. Most infants do not have associated anomalies, and of those that do, intestinal atresia is the most common, occurring in 10% to 15% of patients with gastroschisis.

The infant with gastroschisis should be delivered in a center with a neonatal ICU and access to pediatric surgery. A nasogastric tube should be placed to decompress the bowel. Dehydration and hypothermia from insensible fluid and heat losses are prevented by immediate administration of intravenous fluids, wrapping the viscera with a moist gauze dressing, and placement of the lower portion of the newborn’s body in a bowel bag. The viscera should be supported so that they remain on top of the abdomen, rather than falling over to the side, to avoid venous outflow obstruction, which can augment bowel edema. Broad-spectrum antibiotics are administered.

Once the infant is resuscitated, the viscera are examined for evidence of atresia, mesenteric injury, or bowel compromise. Rectal irrigation is often performed to aid in evacuating meconium to reduce the visceral volume, and a Foley catheter is inserted to decompress the bladder. The bowel is often thickened, probably due to contact with the amniotic fluid, such that individual bowel loops are poorly defined (Fig. 9-5). If an atresia is suspected at the time of birth, primary abdominal wall closure is still first achieved in the majority of patients. If an atresia is then confirmed in the postnatal period, re-exploration with repair of the atresia should be performed at 3 to 6 weeks. In some circumstances, an enterostomy is required, especially in the setting of obvious atresia or compromised bowel.

Primary closure of the abdominal wall is successful in approximately 80% of newborns. “Sutureless” closure using the umbilical stalk may be successful in neonates with adequate abdominal wall compliance and a small defect (Fig. 9-6). While the fascia has traditionally been closed with sutures at birth, recent experience has suggested success with using the umbilicus to patch the fascial defect. During attempted reduction of the viscera, it is vital to recognize any compromise in physiologic status of the neonate during closure such as significant increase in airway pressures, unstable hemodynamics, or development of acidosis due to excess intra-abdominal pressure. Examination of the newborn’s lower body may demonstrate edema and cyanosis due to venous congestion. If signs of increased abdominal pressure are observed, the bowel should be removed to decompress the abdomen and a silo placed.

If the bowel cannot be safely reduced, a staged closure using a prosthesis is useful (Fig. 9-7). Spring-loaded, preformed silos are now available in different sizes and are easy to place, which precludes the need to manually construct a silo. In some cases, the abdominal wall defect is enlarged to avoid a funnel type configuration of the silo, which could lead to compression of the bowel at the base of the silo with ischemia and necrosis. The silo is wrapped in betadine-moistened gauze to prevent infection and suspended from the over-bed warmer in order to encourage gravity-assisted reduction of the remaining viscera. The viscera are gradually reduced by compressing or twisting the silo and tying an umbilical tape sequentially lower on the silo once every 12 to 24 hours. Use of a silo may be associated with a decrease in time on the mechanical ventilator and time to initial and full feedings. The viscera are usually reduced within a week such that the base of the silo is flat. The patient is then taken back to the operating room and the fascia closed. The edge of the opening is incised and the fascia identified circumferentially. Vicryl sutures are then placed to close the fascia; this is often done in a horizontal fashion because the tension is less than with a vertical fascial closure. Fascial closure sometimes leads to physiologic compromise. In that case, a Vicryl or a biosynthetic mesh (Surgisis ES; Cook Tissue Engineering Products, Bloomington, IN) may be sewn to the fascia, although a ventral hernia may result. This includes infants in whom the bowel cannot be completely reduced and those with concern for ischemic bowel, because a silo allows one to directly monitor the bowel status.

Following reduction of the viscera, return of GI function often is delayed: median time to initiation of feedings is 15 days, with full enteral intake achieved by 22 days. Nearly all patients with gastroschisis require nutritional support with parenteral nutrition and central venous access. Postoperative bowel obstruction is relatively uncommon, and an upper GI contrast study is performed after approximately 2 to 3 weeks when GI function fails to normalize. If the silo separates from the fascia, a pseudomembrane has usually formed beneath the silo, which can be allowed to granulate. Skin graft closure of the abdominal wall is possible once infection has been resolved using topical silver sulfadiazine.

Survival is over 90%. However, the complications that arise pose a considerable threat in the neonate with gastroschisis. NEC may occur during advancement of enteral feeds after gastroschisis closure. Neonates with gastroschisis may be at increased risk of developing NEC due to enhanced mucosal permeability, intestinal dysmotility, or intestinal atresia. Patients with gastroschisis who develop NEC have lower birth weight and are more likely to be formula fed. An enterocutaneous fistula may develop from an anastomotic leak or intestinal injury. Malrotation, if not corrected at the time of the initial operation, may rarely result in jejunal obstruction due to Ladd bands or volvulus. SBS may occur as a result of bowel dysfunction or loss of bowel due to atresia or one of the complications outlined previously. By 6 months of age, intestinal function, in general, has returned to normal. GERD is observed in 16% of patients with gastroschisis, likely related to the presence of increased intra-abdominal pressure.

Omphalocele

Omphalocele differs from gastroschisis in that it consists of an abdominal wall defect at the umbilicus, a peritoneal and amnion covering or sac, a normal umbilical cord that attaches to the sac, and umbilical vessels that radiate over the defect (Fig. 9-8). Patients with omphalocele have a ruptured sac in approximately 10% of cases; however, the underlying diagnosis is still contrasted from gastroschisis due to the characteristics noted above. The liver is within the defect in approximately half of the patients.

Approximately 30% to 60% of newborns with omphalocele present with concomitant anomalies which may be a source of major morbidity and mortality. Congenital heart disease occurs in 20%, abnormal karyotypes are observed in 29%, and the Beckwith–Wiedemann syndrome is seen in 10% of patients. Patients with Beckwith–Wiedemann may have macroglossia, leading to airway obstruction, and may also present with hypoglycemia, which requires prompt preoperative recognition and treatment.

The initial management of omphalocele is similar to that described for gastroschisis. Hypothermia and dehydration are avoided and treatment with broad-spectrum antibiotics is initiated. Endotracheal intubation and mechanical ventilation may be required if respiratory distress is present, often related to underlying pulmonary hypoplasia. Infants born with giant or large omphalocele greater than 4 to 6 cm in size and/or having the liver in a central position have an increased association with pulmonary hypoplasia and respiratory distress and therefore may require prolonged support with mechanical ventilation. During initial resuscitation, the sac is left intact and is covered with saline-soaked gauze to prevent desiccation and to decrease heat and fluid losses. Evaluation for other chromosomal and developmental anomalies, especially those related to congenital heart disease, is undertaken.

If the defect is <4 cm in size, it is considered a hernia of the umbilical cord. Closure of a defect of this size is often straightforward and may be amenable to primary closure. Omphaloceles >4 cm are typically more challenging and complicated to manage, and are associated with a poorly developed peritoneal cavity (Fig. 9-4). Skin coverage of the omphalocele defect is the primary goal.

Traditionally, the omphalocele sac is excised during staged reduction, except for where it is adherent to the liver. Excision of the sac in that location could result in liver injury and bleeding. Should bleeding occur, pressure and clot-enhancing agents should be applied. Unfortunately, once the sac is excised, there is time pressure to achieve visceral reduction. Instead, surgeons have recommended leaving the sac intact and sequentially gathering the sac to achieve reduction (Fig. 9-9). Once reduction is accomplished, the fascia may be closed as described for a gastroschisis. A currently popular approach is to use external compression by wrapping of the omphalocele to augment reduction of the viscera while allowing the sac to epithelialize over several months. Application of Silvadene rather than mercurochrome, which can cause mercury poisoning, results in eschar formation of the sac. Contraction and flattening of the omphalocele is often the result, although a ventral hernia usually remains.

When these approaches do not work, or in the case of a ruptured omphalocele, the skin–amnion junction is incised circumferentially and the fascia mobilized; caution should be exercised when dissecting over the superior aspect of the liver since the hepatic veins are often superficial in this location because of the downward position of the liver in the omphalocele. If care is not exercised, injury to and bleeding from the hepatic veins can result. Examination of the diaphragm should be performed to check for the presence of an associated defect. With a large omphalocele, primary closure is rarely possible. Thus, a silo is created from Dacron-reinforced silastic or Gore-Tex (W.L. Gore and Assoc., Inc.; Newark, DE) and is sewn to the fascial edges. The mesh is sequentially gathered in the midline until the fascial edges are nearly approximated. During this process, one must balance aggressively tightening the mesh with avoiding undue tension on the mesh: excess tension could lead to premature separation of the mesh from the fascia. The patient should also be monitored for evidence of high intraabdominal pressure resulting in hypercarbia, oliguria, hemodynamic compromise, and acidosis. Such high pressures could compromise ventilation, renal blood flow, cardiac output, intestinal perfusion, and venous drainage from the lower extremities. Once it is nearly approximated, the fascia can then be closed with removal of the mesh, although a reasonable option is to close the skin while leaving part of the mesh in place. If the mesh separates, granulation tissue often remains underneath. This presents a challenging wound care problem: application of homograft and other artificial wound coverings may be considered. One option is to allow the wound to epithelialize. An alternative is split-thickness skin graft placement, which is often effective once any wound infection is controlled.

As with gastroschisis, return of gastrointestinal function is often delayed in patients with a large omphalocele. Parenteral nutrition is initiated within the first few days of life, requiring early central venous access. Mechanical bowel obstruction can occur, but is unusual. Lung and chest wall hypoplasia and chronic respiratory insufficiency are reasonably common among patients with giant omphaloceles, and tracheostomy tube placement may be required. Staged reduction in patients with giant omphalocele applies pressure upon the diaphragm, which complicates lung dysfunction.

Survival is 80% to 90%, and mortality is impacted primarily by the associated anomalies. In children with omphalocele, the incidence of gastroesophageal reflux (GER) is high (43%), likely due to the elevated intraabdominal pressure. Ventral hernias often result when a nonsurgical approach is employed. A staged approach to closure of the ventral hernia will be required in those with massive ventral hernias. The incidence of cryptorchidism is increased in patients with omphalocele (16%); this is thought to be related to decreased intraabdominal pressure during the typical period of physiologic in-utero testicular descent.

Malrotation

At approximately 8 to 10 weeks of development, the midgut rotates 270 degrees counterclockwise, which leads to fixation of the proximal small bowel at the ligament of Treitz, attachment of the cecum and right colon in the right lower quadrant, and broad fixation of the base of the small bowel mesentery to the retroperitoneum. If this rotation fails to occur, the small intestine remains on the right side of the abdomen, the cecum is typically at a location other than the right lower quadrant, and the bowel remains unfixed. The entire midgut is mobile and prone to rotation on a central axis or volvulus, which is the mode of presentation in 85% of newborns and 31% of patients of all ages. Volvulus may compromise superior mesenteric artery (SMA) inflow and venous blood outflow, leading to ischemia or necrosis of the entire small intestine and transverse colon. In addition, peritoneal bands known as Ladd bands, which are responsible for drawing the cecum into the right lower quadrant, cross over and may partially obstruct the distal duodenum and proximal small bowel. Eighty-nine percent of patients with symptomatic malrotation present in the first year of life, with 50% in the first week and 65% in the first month, leaving only 11% to present after the first year. An occasional older patient presents with intermittent midgut volvulus and recurrent abdominal pain that may mimic other common causes of an acute abdomen.

The failure to recognize this entity promptly may result in the loss of the entire midgut. The primary symptom of acute midgut volvulus is sudden onset of bilious vomiting; therefore it is essential the provider consider the diagnosis of malrotation in any infant with bilious vomiting. With midgut volvulus, as the distal bowel empties, the abdomen is often scaphoid rather than distended. Physical examination is unexpectedly without peritonitis until later in the process when intestinal ischemia and necrosis develop. At that point, abdominal distension, tenderness, and hematochezia are often present. As the course progresses, hypovolemia, shock, and acidosis ensue. To avoid these sequelae, an emergent contrast UGI study should be performed. UGI evaluation of the course of the duodenum demonstrates that the duodenojejunal junction remains to the right of the midline, and the normal posterior and cephalad fixation of the duodenum at the ligament of Treitz is absent (Fig. 9-10). If volvulus is present, a corkscrew appearance of the duodenojejunal junction is noted. Ultrasound may be helpful in diagnosing midgut volvulus by identifying an abnormal SMA and superior mesenteric vein (SMV) relationship as well as inability to identify the duodenum passing behind the SMA.

Midgut volvulus is a surgical emergency. Once the diagnosis of malrotation is made in the symptomatic patient, immediate laparotomy is indicated even if radiologic and clinical signs of volvulus are absent (Fig. 9-11). The child should be rapidly resuscitated either in the operating room or while preparing the operating room. A Ladd procedure consists of the following: (i) exploration of the midgut; (ii) counterclockwise derotation of a midgut volvulus (if present); (iii) performance of a Kocher maneuver with division of Ladd bands; (iv) broadening of the mesentery of the proximal jejunum and the transverse colon by division of adhesions between these two structures—along with subsequent general bowel adhesion formation, broadening the mesentery will reduce the incidence of recurrent volvulus (Fig. 9-12); (v) return of the intestine to the abdomen without any twists in the mesentery, and placement of the cecum in the left lower quadrant to further broaden the mesentery; and (vi) appendectomy because of the potential of a difficult diagnosis of appendicitis in the future with the inappropriate location of the appendix. Failure to completely detorse the bowel or lyse all of Ladd bands may result in persistent obstruction or recurrence of volvulus. There is no evidence to support fixation of the intestine to the retroperitoneum. If compromised bowel is noted, a second look at 24 hours is an option to minimize the amount of bowel resected and short gut syndrome. If the surgeon encounters grossly necrotic bowel it may be necessary to resect and plan for reexploration at 24 hours. Performance of an ileostomy is usually necessary only if there is continued question of intestinal viability at reexploration. Necrosis of the entire midgut makes survival unlikely; resection of the entire midgut is associated with high morbidity and lifelong parenteral nutrition or small bowel transplantation in most cases. Postoperative complications may occur such as recurrence of midgut volvulus; although infrequent, <2% of patients have recurrence and it is thought to be related to a failure to lyse all the Ladd bands. Adhesive bowel obstruction occurs in 1% to 10% of patients, and perioperative mortality is 4% and is primarily associated with sepsis from massive intestinal necrosis. Mortality is at least 50% in those with extensive (>75%) small bowel infarction. Mortality may be also increased in those with congenital heart disease. One review of patients with malrotation and heterotaxy identified nearly 10% in-hospital mortality, due to cardiac causes in those who underwent a Ladd procedure. However, the authors noted that the deaths were not due to the Ladd procedure and that 27% of the patients with heterotaxy and symptomatic malrotation had midgut volvulus. In another study, 18% of patients with heterotaxy died after a Ladd procedure: all deaths occurred more than 1 month after the operation and were due to the underlying cardiac disease. It is therefore important for the surgical and cardiology teams to discuss the potential risks and benefits of a Ladd procedure in patients with congenital heart disease and asymptomatic malrotation.

Esophageal Atresia/Tracheoesophageal Fistula

Providers may be aware of the potential for the diagnosis of esophageal atresia (EA) from a diagnostic ultrasound performed during gestation demonstrating polyhydramnios. Postnatally, a neonate may have difficulty handling secretions and may have symptoms of choking or coughing with feeding. Usually an unsuccessful attempt is made at passing a nasogastric or orogastric tube. Curling of the tube in the dilated proximal esophageal pouch may be seen on plain radiograph and is pathognomonic for EA (Fig. 9-13). The neonate is always at risk for aspiration, especially if EA goes unrecognized. In addition, gastric secretions may reflux into the lungs through a distal tracheoesophageal fistula (TEF), if present, and lead to further lung contamination and the development of pneumonia. Maintaining the newborn in a strict 30-degree to 45-degree upright position will inhibit reflux of gastrointestinal contents into the tracheobronchial tree. Intravenous antibiotics should be administered prophylactically if the patient exhibits signs of pneumonia. Mechanical ventilation should be performed only if necessary because of the risk of ventilation through a TEF leading to gastric distention, and potentially, perforation. Respiratory insufficiency, especially in the setting of prematurity and respiratory distress syndrome (RDS), may be associated with a decrease in pulmonary compliance. In that setting, the TEF competes with and prevents adequate pulmonary ventilation. Occlusion of the TEF via lower esophageal occlusion with a balloon catheter introduced through a gastrostomy site or thoracotomy with division of the fistula may be required with or without performance of an esophageal anastomosis esophagogastrostomy).

Air in the abdomen on radiograph suggests the presence of a distal TEF (85%), and the absence of distal air indicates a pure EA (7%) (Fig. 9-14). Radiologic evaluation, performed with careful administration of contrast medium into the upper pouch with the patient sitting upright to avoid aspiration, will verify the diagnosis of EA and identify a proximal TEF, which is present in approximately 1% of patients. Proximal fistulas are frequently missed at the time of operation because the fistula may be proximal, above the level of routine dissection. The presence of a small proximal pouch suggests that a proximal fistula may be present and that the anastomosis may be under tension. Bronchoscopy may help to identify a proximal fistula in the operating room prior to repair of the EA/TEF. However, bronchoscopy may miss small proximal fistulas, and contrast study of the proximal pouch appears to be an equally useful adjunctive test with low risk of aspiration when appropriately performed (Fig. 9-15).

Greater than half of the patients with EA/TEF have associated anomalies. Approximately 15% of patients have a constellation of findings compatible with the VATER or VACTERL association (vertebral defects, anal atresia, cardiac anomalies, TEF and EA, renal defects, and limb abnormalities). The most common anomalies are cardiac (38%) and are responsible for many of the deaths associated with EA and TEF. Renal anomalies occur in 17% of patients.

In general, patients with EA and a distal TEF have adequate esophageal length to allow primary reconstruction. A repair is generally planned within the first 24 to 48 hours unless contraindicated by prematurity, the presence of congenital heart disease, or critical illness rendering the operative and anesthetic risks unacceptable. In that case, temporizing with proximal pouch replogle suction and a gastrostomy tube with plans for delayed repair may be the best strategy. When repair is performed, an approach through the right chest using a muscle-sparing incision is typically performed with access via the fourth intercostal space. The presence of a right aortic arch, found in 2% of patients with the EA/TEF anomaly, should be identified on echocardiography so that the surgical team can consider a left thoracic approach. A retropleural approach is historically used in order to contain a potential leak, although there is no evidence to suggest that such an approach is beneficial. The distal TEF is identified in the region of the carina and is divided. Prior to division of the fistula, maintenance of oxygenation may be tenuous and requires that the surgeon intermittently allow expansion of the right lung; this problem usually resolves once the fistula is ligated. A few millimeters of esophageal tissue are left on the trachea during division of the TEF in order to avoid compromise of the tracheal lumen. The tracheal closure is checked for an air leak with saline submersion and application of sustained airway pressure. The distal esophagus can be mobilized with minimal risk of devascularization. The proximal esophageal pouch can be identified by having the anesthesiologist advance a catheter placed through the mouth into the pouch. A suture is placed in the apex of the proximal pouch for manipulation in order to avoid trauma due to repeated grasping of the tissue. The pouch is mobilized in the upper mediastinum; care is taken while mobilizing the anterior esophagus because of the risk of entry into the membranous trachea. Use of cautery should be limited, especially in the apex of the thorax, because of the risk of thermal injury to the recurrent laryngeal nerves. An esophagoesophagostomy is performed, taking care to ensure that sutures include the full thickness of the esophagus. Some patients with EA and a distal TEF will have a longer gap between the proximal and distal esophagus (>2 vertebral bodies). The anastomosis may be performed under tension. Some surgeons maintain the patient sedated with the head in flexed position to decrease postoperative anastomotic tension. If the gap between the upper and lower pouches is long enough, the TEF may be ligated and divided and the distal pouch tacked to the prevertebral fascia, with reconstruction performed after 8 to 12 weeks. A nasogastric tube is passed through the anastomosis into the stomach to ensure patency of the distal esophagus. Gastrostomy tubes may be indicated if the presence of other anomalies suggests that prolonged tube feeding will be required. A drainage tube is typically placed near, but not on, the anastomosis at the end of the operation to contain postoperative anastomotic leaks. Small openings in the pleura are unimportant and should not be closed when a retropleural approach is used. Oropharyngeal suctioning is limited to <6 cm from the lips in order to avoid trauma to the anastomosis. An esophageal contrast study is performed approximately 1 week after operation. If the anastomosis is intact, feedings are initiated, antibiotics are discontinued, and the retropleural chest tube is removed. Complications include anastomotic leaks, which occur in 16% of cases and typically resolve without intervention. Silk sutures are associated with a two- to threefold increase in the incidence of anastomotic leak. Postoperative strictures may be found in up to 40% of cases and are often associated with leaks, anastomotic tension, and GER. GER occurs in up to 70% of patients with EA/TEF and may require a fundoplication, which may result in dysphagia by augmenting the esophageal dysfunction typically associated with an EA/TEF.

In patients with isolated EA without a TEF (pure esophageal atresia), the distal esophagus is typically short, which precludes immediate repair. Patients with pure esophageal atresia that are not amenable to a primary approach may be repaired at 8 to 12 weeks with a delayed primary anastomosis. The management involves initial placement of a gastrostomy tube, allowing for growth of the proximal and distal pouch over the ensuing 3 months prior to an attempt at a primary repair (Fig. 9-16). Daily dilation of the proximal pouch may enhance lengthening. There are other alternative approaches that may be required, including proximal pouch myotomies to extend length. However, these may be associated with complications such as leaks, strictures, outpouching of the esophagus at the site of the myotomy, and esophageal dysfunction. In patients with very long gaps, replacement of the esophagus with a natural conduit such as the stomach, colon, or even the small bowel may be the best option.

Other techniques are available that may lengthen the esophagus, including the Kimura procedure, in which an esophagostomy is formed on the chest and sequentially lengthened every 2 to 3 weeks by advancing the esophagostomy inferiorly along the chest wall. This technique allows sham feedings, which are important for normal feeding development to take place.

Another more recent approach to augment esophageal length was developed by Foker. With this approach, continuous traction is used to slowly approximate the proximal and distal ends of the esophagus, followed by performance of an anastomosis (Fig. 9-17). The traction is applied by sutures placed on the ends of the esophagus which are brought out through the lateral, superior, and inferior rib interspaces, respectively. Tension is steadily applied to allow for growth and eventual approximation. With the Foker technique, the patient is at risk for postoperative strictures and reflux that can be managed with dilations and fundoplication, respectively. If the sutures pull through the ends of the esophagus there is the potential for esophageal leak. Options when this complication occurs are to replace the sutures with repair of the leak (if present) or to convert to a cervical esophagostomy with plans for esophageal reconstruction later.

In general, all attempts are made to salvage the native esophagus. However, when the esophagus cannot be approximated or if complications of stricture, recurrent GER, or esophageal dysfunction persist, esophageal replacement is an alternative. Right or left colon, jejunum, or the stomach, either as a reversed-gastric tube or a gastric transposition, can be used. Although an effective solution to establishing esophageal continuity, the complication rate with esophageal replacement is substantial and includes an anastomotic leak rate of approximately 30%, stricture formation in 20% to 60%, and a mortality of 5%. Anastomotic leaks almost always resolve spontaneously. A variety of options are available for esophageal replacement.

When a colon conduit is used, it can consist or right or left colon and be placed behind the hilum of the lung on either side or in a substernal position, although the latter is associated with a higher stenosis rate. A vagotomy is effective in preventing the development of ulcers when a colon conduit is used. The colon may become redundant in the chest (sink trap deformity), leading to dysfunction and stasis (16%). Reoperation is necessary in approximately 50% of patients and is most often performed to redo the esophagocolic or cologastric anastomoses due to strictures or to correct the redundancy. Gastrocolic reflux may also occur, and approximately 20% will ultimately require replacement of the colon graft, which is best managed by performance of a gastric transposition or a free jejunal graft.

Another option for esophageal replacement is the reverse gastric tube, which is formed by creating a tube from the greater curvature of the stomach. This is most often brought up to the neck through what would have been the esophageal bed. Complications are leak from the long suture line and compromise of the stomach size, especially in newborns with a diminutive stomach. Finally, gastric transposition is a successful option because the blood supply to the stomach is excellent and the operation is technically easier than other alternatives. This option can be used even when previous operations have been performed on the stomach. The right and left gastroepiploic arteries are maintained intact while the stomach is otherwise mobilized. The distal esophageal segment is excised and the fundus is brought through the posterior mediastinum, which limits the potential complication of gastric distension. The posterior aspect of the stomach must be anchored to the sternocleidomastoid muscles in the infant and to the prevertebral fascia in the older patient to prevent retraction of the stomach into the thorax. A pyloromyotomy should be performed to enhance gastric emptying. The dumping syndrome occurs in a minority of patients in the postoperative period but typically resolves over the first year. Care must be taken to avoid a twist in any of the conduits performed, which may result in ischemia or obstruction. Dissection must be maintained on the proximal esophagus to avoid injury to the recurrent laryngeal nerves.

The simultaneous presentation of EA/TEF and duodenal atresia is a challenging clinical situation. Duodenal atresia occurs in 10% of patients with isolated EA, and the lack of air in the GI tract in the setting of EA without a TEF can delay the diagnosis of duodenal atresia until a gastrostomy tube is placed. An intraoperative contrast study at the time of gastrostomy tube placement helps to identify this combined anomaly, although this is not routinely performed. Imperforate anus, which is part of the VACTERL constellation of findings, should be typically addressed by performing a colostomy.

Patients with a TEF but no EA (4%) often have episodes of gastric distention during crying and choking, recurrent pneumonia, and cyanotic spells during feeding. The diagnosis is best made by a contrast swallow or bronchoscopy, which may demonstrate the H-type fistula between the trachea and esophagus. A Fogarty catheter may be placed through the fistula at the time of bronchoscopy to help with identification of the fistula at operation. Ligation of the fistula is usually performed via a right cervical approach. The recurrent laryngeal nerve must be identified to prevent injury, the most common complication of this procedure. Recurrence of the fistula is rare.

Overall survival rate is 95%. Mortality is usually secondary to associated anomalies and is increased with the presence of major cardiac disease and birth weight <1500 g (Table 9-1). One of the most difficult decision-making situations involves the premature newborn with RDS and EA/TEF because the associated ventilator leak through the fistula increases with airway pressure escalation; therefore, ligation of the fistula is ideally performed before compromised respiratory status precludes a safe operation, requiring close monitoring and keen judgement. Early thoracotomy and ligation of the fistula provides an ability to ventilate and prevents gastric distension, though this decision must be weighed against the overall clinical status of the neonate.

Immediate postoperative complications include small anastomotic leaks on postoperative contrast study in 15% of EA/TEF patients with primary repair. Almost all small leaks will resolve spontaneously with continuation of IV antibiotics and chest tube drainage. A repeat study is performed 1 week later, and oral feedings are held until the leak resolves. Disruption of the anastomosis occurs in approximately 5% due to excess tension, ischemia, or poor surgical technique, and presents with persistent pneumothorax, respiratory distress, pleural effusion, and/or sepsis. The disruption should be managed with either direct repair, preferably with reinforcement of the anastomosis with an intercostal muscle flap or a pleural or pericardial patch, or with formation of a cervical esophagostomy and placement of a gastrostomy tube with subsequent esophageal replacement. Stricture formation occurs in approximately 15% of cases and is often associated with a prior anastomotic leak. Most strictures are responsive to repeated antegrade dilatation initially at a frequency of approximately every 2 to 3 weeks. Esophagoscopy should be performed before dilatation to assess the anastomotic caliber and after to ensure that full-thickness perforation has not occurred. Hurst-Maloney dilators may be sequentially passed to dilate a slightly narrowed stricture. In narrow strictures, a wire passed under endoscopic and/or fluoroscopic guidance will allow safe passage of sequentially larger Savory dilators or balloon dilators under fluoroscopic guidance to safely enlarge the anastomosis. Contrast injection at the end of the dilatation can be performed to identify a leak at the site of the stricture. Occasionally, refractory strictures may require resection or even esophageal replacement. Refractory strictures may be due to the presence of reflux, which occurs frequently in patients with EA/TEF. Strictures due to GER usually respond to dilatation once a fundoplication has been performed. Thus, the presence of GER should be investigated if a stricture does not respond after two or three dilatations.

Leak from the trachea or compromise of the tracheal lumen is unusual but requires operation in the former and bronchoscopic evaluation in the latter. Recurrent TEF occurs in 3% of cases, is usually associated with a postoperative leak, and requires reoperation. Recurrent pneumonia, coughing, and choking are frequently noted. Esophagram with the patient prone and/or with balloon catheter obstruction of the distal esophagus during esophageal contrast administration can enhance identification of the fistula. Bronchoscopy with attempts at passage of a catheter through a potential fistula or instillation of dilute methylene blue into the trachea with esophageal assessment for the presence of blue dye will frequently reveal the presence of a recurrent TEF. High-resolution CT may help to identify a recurrent fistula or a missed proximal fistula. Thoracotomy with fistula ligation is required. A 2 Fr balloon catheter should first be passed through the fistula under bronchoscopic guidance to allow intraoperative identification of the fistula. Once the fistula is ligated, a pleural or pericardial flap should be interposed between the trachea and esophagus to help prevent recurrence. Injection of fibrin glue into the fistula may result in closure of the communication without thoracotomy.

The most common long-term problems associated with EA include GER (40%–70%), tracheomalacia (16%), and esophageal dysfunction. GER is likely due to the tension placed on the distal esophagus with compromise of the native antireflux mechanisms and shortening of the intra-abdominal esophagus. Recurrent pneumonia, reactive airway disease, cyanotic spells, and persistent anastomotic stricture can be symptoms/signs of GER in the EA/TEF patient. GER symptoms are present in at least 20% to 40% of adult patients with previous EA/TEF. Evaluation with upper GI contrast study and/or 24-hour pH probe may document the diagnosis. GER is typically first managed with prokinetic agents and proton pump inhibitors, although approximately 30% to 40% of patients require a fundoplication. A 360-degree Nissen fundoplication is most frequently performed, although a Nissen fundoplication may exacerbate the esophageal dysfunction associated with EA/TEF. Under those circumstances, recurrent reflux, esophageal dilation and dysfunction, and dysphagia may result in an adverse outcome. A Thal fundoplication is a reasonable alternative because of the partial nature of the wrap, but the failure rate has been high. As a result, most surgeons prefer to perform a “floppy” Nissen fundoplication. Because studies have demonstrated a relatively high incidence of Barrett’s esophagitis among patients with repaired EA/TEF (5%–7%), long-term endoscopic surveillance is important.

Tracheomalacia results in stridor and a barking cough in newborns, although some patients may present with apnea, as the result of a weakness in the tracheal wall such that the anterior and posterior tracheal walls coapt during expiration. Bronchoscopy during spontaneous breathing demonstrates the collapse in the distal third of the trachea. Mild symptoms in most patients can be followed, with expected resolution as the patient grows. Life-threatening symptoms require operation in 6%. An aortopexy, in which the anterior aspect of the aortic arch is approximated to the posterior sternum, is effective in almost all patients at resolving the symptoms of tracheomalacia. A Palmaz airway stent or tracheostomy may be of benefit should the aortopexy prove to be inadequate. Frequently, it is difficult to determine whether the symptoms observed are due to tracheomalacia or GER.

Esophageal dysmotility is present in the majority of EA/TEF children, and 40% to 75% of adult EA/TEF patients have mild-to-severe dysphagia and esophageal dysmotility. In most cases, the dysphagia is tolerable and in infants can be managed by slowing the pace of feeding and feeding while the patient is sitting up. Scoliosis develops in 8% of patients, probably due to fusion of the ribs at the site of the thoracotomy, which prevents ipsilateral spine growth. Anterior chest wall deformities are observed in 20%, though a muscle sparing or thoracoscopic (see below) approach may decrease the incidence of this complication. Foreign body impaction occurs in 13% of patients with corrected EA/TEF, usually during the child’s first 5 years of life.