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Surgery_Schwartz. that is aspirated, although other materials (pop-corn, for instance) may also be involved. A solid foreign body often will cause air trapping, with hyperlucency of the affected lobe or lung seen especially on expiration. Oil from the peanut is very irritating and may cause pneumonia. Delay in diagnosis can lead to atelectasis and infection. The most common ana-tomic location for a foreign body is the right main stem bronchus or the right lower lobe. The child usually will cough or choke while eating but may then become asymptomatic. Total respira-tory obstruction with tracheal foreign body may occur; however, respiratory distress is usually mild if present at all. A unilateral wheeze is often heard on auscultation. This wheeze often leads to an inappropriate diagnosis of “asthma” and may delay the correct diagnosis for some time. Chest X-ray will show a radi-opaque foreign body, but in the case of nuts, seeds, or plastic toy parts, the only clue may be hyperexpansion of the affected


Surgery_Schwartz

Surgery_Schwartz. delay the correct diagnosis for some time. Chest X-ray will show a radi-opaque foreign body, but in the case of nuts, seeds, or plastic toy parts, the only clue may be hyperexpansion of the affected lobe on an expiratory film or fluoroscopy. Bronchoscopy confirms the diagnosis and allows removal of the foreign body. It can be a very simple procedure or it may be extremely difficult, espe-cially with a smooth foreign body that cannot be grasped easily or one that has been retained for some time. The rigid broncho-scope should be used in all cases, and utilization of the optical forceps facilitates grasping the inhaled object. Epinephrine may be injected into the mucosa when the object has been present for a long period of time, which minimizes bleeding. Bronchiectasis may be seen as an extremely late phenomenon after repeated infections of the poorly aerated lung and may require partial or total resection of the affected lobe. The differential diagnosis of a bronchial foreign body


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Surgery_Schwartz. extremely late phenomenon after repeated infections of the poorly aerated lung and may require partial or total resection of the affected lobe. The differential diagnosis of a bronchial foreign body includes an intraluminal tumor (i.e., carcinoid, hemangioma, or neurofibroma).Foreign Bodies and Esophageal Injury. The most common foreign body in the esophagus is a coin, followed by small toy parts. Toddlers are most commonly affected. The coin is retained in the esophagus at one of three locations: the cricopharyngeus, the area of the aortic arch, or the gastroesophageal junction, all of which are areas of normal anatomic narrowing. Symptoms are variable depending on the anatomic position of the foreign body and the degree of obstruction. There is often a relatively asymptomatic period after ingestion. The initial symptoms are gastrointestinal, and include dysphagia, drooling, and dehydra-tion. The longer the foreign body remains in the esophagus with oral secretions unable to transit


Surgery_Schwartz

Surgery_Schwartz. ingestion. The initial symptoms are gastrointestinal, and include dysphagia, drooling, and dehydra-tion. The longer the foreign body remains in the esophagus with oral secretions unable to transit the esophagus, the greater the incidence of respiratory symptoms including cough, stridor, and wheezing. These findings may be interpreted as signs of upper respiratory infections. Objects that are present for a long period of time—particularly in children who have underlying neurological impairment—may manifest as chronic dysphagia. The chest X-ray is diagnostic in the case of a coin. A contrast swallow, or preferably an esophagoscopy, may be required for nonradiopaque foreign bodies. Coins lodged within the upper Brunicardi_Ch39_p1705-p1758.indd 171612/02/19 11:26 AM 1717PEDIATRIC SURGERYCHAPTER 39Figure 39-8. The five varieties of esophageal atresia and tracheoesophageal fistula. A. Isolated esophageal atresia. B. Esophageal atresia with tracheoesophageal fistula between proximal


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Surgery_Schwartz. 39Figure 39-8. The five varieties of esophageal atresia and tracheoesophageal fistula. A. Isolated esophageal atresia. B. Esophageal atresia with tracheoesophageal fistula between proximal segment of esophagus and trachea. C. Esophageal atresia with tracheoesophageal fistula between distal esophagus and trachea. D. Esophageal atresia with fistula between both proximal and distal ends of esophagus and trachea. E. Tracheoesophageal fistula without esophageal atresia (H-type fistula).esophagus for less than 24 hours may be removed using Magill forceps during direct laryngoscopy. For all other situations, the treatment is by esophagoscopy, rigid or flexible, and removal of the foreign body. In the case of sharp foreign bodies such as open safety pins, extreme care is required on extraction to avoid injury to the esophagus. Rarely, esophagotomy is required for removal, particularly of sharp objects. Diligent follow-up is required after removal of foreign bodies, especially batteries,


Surgery_Schwartz

Surgery_Schwartz. to avoid injury to the esophagus. Rarely, esophagotomy is required for removal, particularly of sharp objects. Diligent follow-up is required after removal of foreign bodies, especially batteries, which can cause strictures, and sharp objects, which can injure the underlying esophagus. In the case of a retained battery, this case should be handled as a surgical emergency, as the negative pole of the battery directly damages the surrounding tissue, and tracheoesophageal fistula, aortic exsanguination, and mediasti-nitis have all been described after local tissue necrosis at the site where the battery has lodged.ESOPHAGUSEsophageal Atresia and Tracheoesophageal FistulaThe management of esophageal atresia (EA) and tracheoesopha-geal fistula (TEF) is one of the most gratifying pediatric sur-gical conditions to treat. In the not so distant past, nearly all infants born with EA and TEF died. In 1939 Ladd and Leven achieved the first success repair by ligating the fistula, placing a


Surgery_Schwartz

Surgery_Schwartz. sur-gical conditions to treat. In the not so distant past, nearly all infants born with EA and TEF died. In 1939 Ladd and Leven achieved the first success repair by ligating the fistula, placing a gastrostomy, and reconstructing the esophagus at a later time. Subsequently, Dr. Cameron Haight, in Ann Arbor, Michigan, performed the first successful primary anastomosis for esopha-geal atresia, which remains the current approach for treatment of this condition. Despite the fact that there are several com-mon varieties of this anomaly and the underlying cause remains obscure, a careful approach consisting of meticulous periopera-tive care and attention to the technical detail of the operation can result in an excellent prognosis in most cases.Anatomic Varieties. The five major varieties of EA and TEF are shown in Fig. 39-8. The most commonly seen variety is esophageal atresia with distal tracheoesophageal fistula (type C), which occurs in approximately 85% of the cases in most series. The


Surgery_Schwartz

Surgery_Schwartz. TEF are shown in Fig. 39-8. The most commonly seen variety is esophageal atresia with distal tracheoesophageal fistula (type C), which occurs in approximately 85% of the cases in most series. The next most frequent is pure esophageal atresia (type A), occurring in 8% to 10% of patients, followed by tracheoesophageal fistula without esophageal atresia (type E). This occurs in 8% of cases and is also referred to as an H-type fistula, based upon the anatomic similarity to that letter Figure 39-9. Barium esophagram showing H-type tracheoesophageal fistula (arrow).(Fig. 39-9). Esophageal atresia with fistula between both proximal and distal ends of the esophagus and trachea (type D) is seen in approximately 2% of cases, and type B, esophageal atresia with tracheoesophageal fistula between distal esophagus and trachea, is seen in approximately 1% of all cases.Etiology and Pathologic Presentation. The esophagus and trachea share a common embryologic origin. At approximately 4 weeks’


Surgery_Schwartz

Surgery_Schwartz. distal esophagus and trachea, is seen in approximately 1% of all cases.Etiology and Pathologic Presentation. The esophagus and trachea share a common embryologic origin. At approximately 4 weeks’ gestation, a diverticulum forms off the anterior aspect of the proximal foregut in the region of the primitive pharynx. This diverticulum extends caudally with progressive formation of the laryngo-tracheal groove, thus, creating a separate trachea and esophagus. Successful development of these structures is the consequence of extremely intricate interplay of growth and transcription factors necessary for rostral-caudal and anterior-posterior specification. The variations in clinically observed EA and TEF that must result in failure of successful formation of these structures are depicted in Fig. 39-8. While definitive genetic mutations have been difficult to identify in isolated EA-TEF, mutations in N-myc, Sox2, and CHD7 have been character-ized in syndromic EA-TEF with associated


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Surgery_Schwartz. in Fig. 39-8. While definitive genetic mutations have been difficult to identify in isolated EA-TEF, mutations in N-myc, Sox2, and CHD7 have been character-ized in syndromic EA-TEF with associated anomalies.Other congenital anomalies commonly occur in asso-ciation with EA-TEF. For instance, VACTERRL syndrome is associated with vertebral anomalies (absent vertebrae or hemi-vertebrae) and anorectal anomalies (imperforate anus), cardiac Brunicardi_Ch39_p1705-p1758.indd 171712/02/19 11:26 AM 1718SPECIFIC CONSIDERATIONSPART IIFigure 39-10. Type C esophageal atresia with tracheoesophageal fistula. Note the catheter that is coiled in the upper pouch and the presence of gas below the diaphragm, which confirms the presence of the tracheoesophageal fistula.defects, tracheoesophageal fistula, renal anomalies (renal agen-esis, renal anomalies), and radial limb hyperplasia. In nearly 20% of the infants born with esophageal atresia, some variant of congenital heart disease occurs.Clinical


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Surgery_Schwartz. renal anomalies (renal agen-esis, renal anomalies), and radial limb hyperplasia. In nearly 20% of the infants born with esophageal atresia, some variant of congenital heart disease occurs.Clinical Presentation of Infants With Esophageal Atresia and Tracheoesophageal Fistula. The anatomic variant of infants with EA-TEF predicts the clinical presentation. When the esophagus ends either as a blind pouch or as a fistula into the trachea (as in types A, B, C, or D), infants present with exces-sive drooling, followed by choking or coughing immediately after feeding is initiated as a result of aspiration through the fistula tract. As the neonate coughs and cries, air is transmitted through the fistula into the stomach, resulting in abdominal dis-tention. As the abdomen distends, it becomes increasingly more difficult for the infant to breathe. This leads to further atelecta-sis, which compounds the pulmonary dysfunction. In patients with type C and D varieties, the regurgitated gastric juice


Surgery_Schwartz

Surgery_Schwartz. more difficult for the infant to breathe. This leads to further atelecta-sis, which compounds the pulmonary dysfunction. In patients with type C and D varieties, the regurgitated gastric juice passes through the fistula where it collects in the trachea and lungs and leads to a chemical pneumonitis, which further exacerbates the pulmonary status. In many instances, the diagnosis is actually made by the nursing staff who attempt to feed the baby and notice the accumulation of oral secretions.The diagnosis of esophageal atresia is confirmed by the inability to pass an orogastric tube into the stomach (Fig. 39-10). The dilated upper pouch may be occasionally seen on a plain chest radiograph. If a soft feeding tube is used, the tube will coil in the upper pouch, which provides further diagnostic cer-tainty. An important alternative diagnosis that must be consid-ered when an orogastric tube does not enter the stomach is that of an esophageal perforation. This problem can occur in infants


Surgery_Schwartz

Surgery_Schwartz. cer-tainty. An important alternative diagnosis that must be consid-ered when an orogastric tube does not enter the stomach is that of an esophageal perforation. This problem can occur in infants after traumatic insertion of a nasogastric or orogastric tube. In this instance, the perforation classically occurs at the level of the piriform sinus, and a false passage is created, which prevents the tube from entering the stomach. Whenever there is any diag-nostic uncertainty, a contrast study will confirm the diagnosis of EA and occasionally document the TEF. The presence of a tracheoesophageal fistula can be demonstrated clinically by finding air in the gastrointestinal tract. This can be proven at the bedside by percussion of the abdomen and confirmed by obtain-ing a plain abdominal radiograph. Occasionally, a diagnosis of EA-TEF can be suspected prenatally on US evaluation. Typical features include failure to visualize the stomach and the pres-ence of polyhydramnios. These findings


Surgery_Schwartz

Surgery_Schwartz. Occasionally, a diagnosis of EA-TEF can be suspected prenatally on US evaluation. Typical features include failure to visualize the stomach and the pres-ence of polyhydramnios. These findings reflect the absence of efficient swallowing by the fetus.In a child with esophageal atresia, it is important to iden-tify whether coexisting anomalies are present. These include cardiac defects in 38%, skeletal defects in 19%, neurologi-cal defects in 15%, renal defects in 15%, anorectal defects in 8%, and other abnormalities in 13%. Examination of the heart and great vessels with echocardiography is important to exclude cardiac defects, as these are often the most important predictors of survival in these infants. The echocardiogram also demonstrates whether the aortic arch is left sided or right sided, which may influence the approach to surgical repair. Vertebral anomalies are assessed by plain radiography, and a spinal US is obtained if any are detected. A patent anus should be confirmed


Surgery_Schwartz

Surgery_Schwartz. sided, which may influence the approach to surgical repair. Vertebral anomalies are assessed by plain radiography, and a spinal US is obtained if any are detected. A patent anus should be confirmed clinically. The kidneys in a newborn may be assessed clinically by palpation. A US of the abdomen will demonstrate the presence of renal anomalies, which should be suspected in the child who fails to make urine. The presence of extremity anomalies is suspected when there are missing digits and confirmed by plain radiographs of the hands, feet, forearms, and legs. Rib anomalies may also be present. These may include the presence of a 13th rib.Initial Management. The initial treatment of infants with EA-TEF includes attention to the respiratory status, decompression of the upper pouch, and appropriate timing of surgery. Because the major determinant of poor survival is the presence of other severe anomalies, a search for other defects including congeni-tal cardiac disease is undertaken in a


Surgery_Schwartz

Surgery_Schwartz. timing of surgery. Because the major determinant of poor survival is the presence of other severe anomalies, a search for other defects including congeni-tal cardiac disease is undertaken in a timely fashion. The initial strategy after the diagnosis is confirmed is to place the neonate in an infant warmer with the head elevated at least 30°. A sump catheter is placed in the upper pouch on continuous suction. Both of these strategies are designed to minimize the degree of aspiration from the esophageal pouch. When saliva accumulates in the upper pouch and is aspirated into the lungs, coughing, bronchospasm, and desaturation episodes can occur, which may be minimized by ensuring the patency of the sump catheter. IV antibiotic therapy is initiated, and warmed electrolyte solu-tion is administered. Where possible, the right upper extremity is avoided as a site to start an IV line, as this location may interfere with positioning of the patient during the surgical repair. Some surgeons


Surgery_Schwartz

Surgery_Schwartz. Where possible, the right upper extremity is avoided as a site to start an IV line, as this location may interfere with positioning of the patient during the surgical repair. Some surgeons place a central line in all patients to facilitate the admin-istration of antibiotics and total parenteral nutrition as needed.The timing of repair is influenced by the stability of the patient. Definitive repair of the EA-TEF is rarely a surgical emergency. If the child is hemodynamically stable and is oxy-genating well, definitive repair may be performed within 1 to 2 days after birth. This allows for a careful determination of the presence of coexisting anomalies and for selection of an expe-rienced anesthetic team.Management of Esophageal Atresia and Tracheoesopha-geal Fistula in the Preterm Infant. The ventilated, prema-ture neonate with EA-TEF and associated hyaline membrane disease represents a patient who may develop severe, progres-sive, cardiopulmonary dysfunction. The tracheoesophageal


Surgery_Schwartz

Surgery_Schwartz. ventilated, prema-ture neonate with EA-TEF and associated hyaline membrane disease represents a patient who may develop severe, progres-sive, cardiopulmonary dysfunction. The tracheoesophageal fis-tula can worsen the fragile pulmonary status as a result of recurrent aspiration through the fistula, and as a result of increased abdominal distention, which impairs lung expansion. Moreover, the elevated airway pressure that is required to ven-tilate these patients can worsen the clinical course by forcing air through the fistula into the stomach, thereby exacerbating the Brunicardi_Ch39_p1705-p1758.indd 171812/02/19 11:26 AM 1719PEDIATRIC SURGERYCHAPTER 39ABCEDAzygos VeinEsophagusEsophagusAzygos VeinFigure 39-11. Primary repair of type C tracheosophageal fistula. A. Right thoracotomy incision. B. Azygous vein transected, proximal and distal esophagus demonstrated, and fistula identified. C. Tracheoesophageal fistula transected and defect in trachea closed. D. End-to-end anastomosis


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Surgery_Schwartz. B. Azygous vein transected, proximal and distal esophagus demonstrated, and fistula identified. C. Tracheoesophageal fistula transected and defect in trachea closed. D. End-to-end anastomosis between proximal and distal esophagus (posterior row). E. Completed anastomosis.degree of abdominal distention and compromising lung expan-sion. In this situation, the first priority is to minimize the degree of positive pressure needed to adequately ventilate the child. This can be accomplished using high frequency oscil-latory ventilation (HFOV). If the gastric distention becomes severe, a gastrostomy tube should be placed. This procedure can be performed at the bedside under local anesthetic, if necessary. The dilated, air-filled stomach can easily be accessed through an incision in the left-upper quadrant of the abdomen. Once the gastrostomy tube is placed and the abdominal pressure is relieved, the pulmonary status can paradoxically worsen. This is because the ventilated gas may pass


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Surgery_Schwartz. quadrant of the abdomen. Once the gastrostomy tube is placed and the abdominal pressure is relieved, the pulmonary status can paradoxically worsen. This is because the ventilated gas may pass preferentially through the fistula, which is the path of least resistance, and bypass the lungs thereby worsening the hypoxemia. To correct this problem, the gastrostomy tube may be placed under water seal, elevated, or intermittently clamped. If these maneuvers are to no avail, liga-tion of the fistula may be required. This procedure can be per-formed in the neonatal intensive care unit if the infant is too unstable to be transported to the operating room. These inter-ventions allow for the infant’s underlying hyaline membrane disease to improve, for the pulmonary secretions to clear, and for the infant to reach a period of stability so that definitive repair can be performed.Primary Surgical Correction. In a stable infant, definitive repair is achieved through performance of a primary


Surgery_Schwartz

Surgery_Schwartz. the infant to reach a period of stability so that definitive repair can be performed.Primary Surgical Correction. In a stable infant, definitive repair is achieved through performance of a primary esopha-goesophagostomy. There are two approaches to this operation: 2open thoracotomy or thoracoscopy. In the open approach, the infant is brought to the operating room, intubated, and placed in the lateral decubitus position with the right side up in prepara-tion for right posterolateral thoracotomy. If a right-sided arch was determined previously by echocardiography, consideration is given to performing the repair through the left chest, although most surgeons believe that the repair can be performed safely from the right side as well. Bronchoscopy may be performed to exclude the presence of additional, upper-pouch fistulae in cases of esophageal atresia (i.e., differentiation of types B, C, and D variants) and identification of a laryngeotracheoesopha-geal cleft.The operative technique


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Surgery_Schwartz. additional, upper-pouch fistulae in cases of esophageal atresia (i.e., differentiation of types B, C, and D variants) and identification of a laryngeotracheoesopha-geal cleft.The operative technique for primary repair is as follows (Fig. 39-11). A retropleural approach is generally used as this technique prevents widespread contamination of the thorax if a postoperative anastomotic leak occurs. The sequence of steps is as follows: (a) mobilization of the pleura to expose the struc-tures in the posterior mediastinum; (b) division of the fistula and closure of the tracheal opening; (c) mobilization of the upper esophagus sufficiently to permit an anastomosis without tension and to determine whether a fistula is present between the upper esophagus and the trachea (forward pressure by the anesthesia staff on the sump drain in the pouch can greatly facilitate dissection at this stage of the operation; care must be taken when dissecting posteriorly to avoid violation of either the lumen of


Surgery_Schwartz

Surgery_Schwartz. staff on the sump drain in the pouch can greatly facilitate dissection at this stage of the operation; care must be taken when dissecting posteriorly to avoid violation of either the lumen of trachea and esophagus); (d) mobilization of the dis-tal esophagus (this needs to be performed judiciously to avoid Brunicardi_Ch39_p1705-p1758.indd 171912/02/19 11:26 AM 1720SPECIFIC CONSIDERATIONSPART IIdevascularization since the blood supply to the distal esopha-gus is segmental from the aorta; most of the esophageal length is obtained from mobilizing the upper pouch since the blood supply travels via the submucosa from above); (e) performing a primary esophagoesophageal anastomosis (most surgeons perform this procedure in a single layer using 5-0 sutures; if there is excess tension, the muscle of the upper pouch can be circumferentially incised without compromising blood supply to increase its length; many surgeons place a transanastomotic feeding tube in order to institute feeds in the


Surgery_Schwartz

Surgery_Schwartz. of the upper pouch can be circumferentially incised without compromising blood supply to increase its length; many surgeons place a transanastomotic feeding tube in order to institute feeds in the early postoperative period); and (f) placement of a retropleural drain and closure of the incision in layers.When a minimally invasive approach is selected, the patient is prepared for right-sided, transthoracic thoracoscopic repair. The same steps as described earlier for the open repair are undertaken, and the magnification and superb optics that are provided by the thoracoscopic approach provide for superb visualization. Identification of the fistula is performed as a first step; this can be readily ligated and divided between tho-racoscopically placed sutures. The anastomosis is performed in a single layer. The thoracoscopically performed TEF repair requires clear and ongoing communication between the oper-ating surgeons and the anesthesiologist; visualization can be significantly


Surgery_Schwartz

Surgery_Schwartz. in a single layer. The thoracoscopically performed TEF repair requires clear and ongoing communication between the oper-ating surgeons and the anesthesiologist; visualization can be significantly reduced with sudden changes in lung inflation, potentially leading to the need to convert to an open repair. Although clear guidelines for patient selection for a thoraco-scopic repair as opposed to an open repair remain lacking, rea-sonable selection criteria include patients over 2.5 kg who are hemodynamically stable and without comorbidities.Postoperative Course. The postoperative management strat-egy of patients with EA-TEF is influenced to a great degree by the preference of the individual surgeon and the institutional culture. Many surgeons prefer not to leave the infants intubated postoperatively to avoid the effects of positive pressure on the site of tracheal closure. However, early extubation may not be possible in babies with preoperative lung disease either from pre-maturity or


Surgery_Schwartz

Surgery_Schwartz. to avoid the effects of positive pressure on the site of tracheal closure. However, early extubation may not be possible in babies with preoperative lung disease either from pre-maturity or pneumonia or when there is any vocal cord edema. When a transanastomotic tube is placed, feeds are begun slowly in the postoperative period. Some surgeons institute parenteral nutrition for several days, using a central line. The retropleural drain is assessed daily for the presence of saliva, indicating an anastomotic leak. Many surgeons obtain a contrast swallow 1 week after repair to assess the caliber of the anastomosis and to determine whether a leak is present. If there is no leak, feedings are started. The principal benefit of the thoracoscopic approach is that postoperative pain is significantly reduced, as is the requirement for postoperative narcotic analgesia.Complications of Surgery. Anastomotic leak occurs in 10% to 15% of patients and may be seen either in the immediate post-operative


Surgery_Schwartz

Surgery_Schwartz. reduced, as is the requirement for postoperative narcotic analgesia.Complications of Surgery. Anastomotic leak occurs in 10% to 15% of patients and may be seen either in the immediate post-operative period or after several days. Early leakage (i.e., within the first 24 to 48 hours) is manifested by a new pleural effusion, pneumothorax, and sepsis and requires immediate exploration. In these circumstances, the anastomosis may be completely dis-rupted, possibly due to excessive tension. Revision of the anas-tomosis may be possible. If not, cervical esophagostomy and gastrostomy placement is required, with a subsequent procedure to reestablish esophageal continuity. Anastomotic leakage that is detected after several days usually heals without intervention, particularly if a retropleural approach is used. Under these cir-cumstances, broad spectrum antibiotics, pulmonary toilet, and optimization of nutrition are important. After approximately a week or so, a repeat esophagram should be


Surgery_Schwartz

Surgery_Schwartz. is used. Under these cir-cumstances, broad spectrum antibiotics, pulmonary toilet, and optimization of nutrition are important. After approximately a week or so, a repeat esophagram should be performed, at which time the leakage may have resolved.Strictures at the anastomosis are not infrequent (10–20%), particularly if a leak has occurred. A stricture may become apparent at any time, from the early postoperative period to months or years later. It may present as choking, gagging, or failure to thrive, but it often becomes clinically apparent with the transition to eating solid food. A contrast swallow or esoph-agoscopy is confirmatory, and simple dilatation is usually cor-rective. Occasionally, repeated dilatations are required. These may be performed in a retrograde fashion, during which a silk suture is placed into the oropharynx and delivered from the esophagus through a gastrostomy tube. Tucker dilators are then tied to the suture and passed in a retrograde fashion from the


Surgery_Schwartz

Surgery_Schwartz. which a silk suture is placed into the oropharynx and delivered from the esophagus through a gastrostomy tube. Tucker dilators are then tied to the suture and passed in a retrograde fashion from the gastrostomy tube and delivered out of the oropharynx. Increas-ing sizes are used, and the silk is replaced at the end of the pro-cedure where it is taped to the side of the face at one end, and to the gastrostomy tube at the other. Alternatively, image-guided balloon dilation over a guide wire may be performed, using intraoperative contrast radiography to determine the precise location of the stricture and to assess the immediate response to the dilation.“Recurrent” tracheoesophageal fistula may represent a missed upper pouch fistula or a true recurrence. This may occur after an anastomotic disruption, during which the recurrent fis-tula may heal spontaneously. Otherwise, reoperation may be required. Recently, the use of fibrin glue has been successful in treating recurrent fistulas,


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Surgery_Schwartz. disruption, during which the recurrent fis-tula may heal spontaneously. Otherwise, reoperation may be required. Recently, the use of fibrin glue has been successful in treating recurrent fistulas, although long-term follow-up is lacking.Gastroesophageal reflux commonly occurs after repair of EA-TEF, potentially due to alterations in esophageal motility and the anatomy of the gastroesophageal junction. The clinical manifestations of such reflux are similar to those seen in other infants with primary gastroesophageal reflux disease (GERD). A loose antireflux procedure, such as a Nissen fundoplication, is used to prevent further reflux, but the child may have feed-ing problems after antireflux surgery as a result of the intrinsic dysmotility of the distal esophagus. The fundoplication may be safely performed laparoscopically in experienced hands, although care should be taken to ensure that the wrap is not excessively tight.Special Circumstances. Patients with type E tracheoesoph-ageal


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Surgery_Schwartz. safely performed laparoscopically in experienced hands, although care should be taken to ensure that the wrap is not excessively tight.Special Circumstances. Patients with type E tracheoesoph-ageal fistulas (also called H-type) most commonly present beyond the newborn period. Presenting symptoms include recurrent chest infections, bronchospasm, and failure to thrive. The diagnosis is suspected using barium esophagography and confirmed by endoscopic visualization of the fistula. Surgical correction is generally possible through a cervical approach with concurrent placement of a balloon catheter across the fis-tula and requires mobilization and division of the fistula. Out-come is usually excellent.Patients with duodenal atresia and EA-TEF may require urgent treatment due to the presence of a closed obstruction of the stomach and proximal duodenum. In stable patients, treat-ment consists of repair of the esophageal anomaly and correc-tion of the duodenal atresia if the infant is stable


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Surgery_Schwartz. a closed obstruction of the stomach and proximal duodenum. In stable patients, treat-ment consists of repair of the esophageal anomaly and correc-tion of the duodenal atresia if the infant is stable during surgery. If not, a staged approach should be utilized consisting of ligation of the fistula and placement of a gastrostomy tube. Definitive repair can then be performed at a later point in time.Primary esophageal atresia (type A) represents a chal-lenging problem, particularly if the upper and lower ends are too far apart for an anastomosis to be created. Under these Brunicardi_Ch39_p1705-p1758.indd 172012/02/19 11:26 AM 1721PEDIATRIC SURGERYCHAPTER 39circumstances, treatment strategies include placement of a gas-trostomy tube and performing serial bougienage to increase the length of the upper pouch. This occasionally allows for primary anastomosis to be performed. Occasionally, when the two ends cannot be brought safely together, esophageal replacement is required using either


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Surgery_Schwartz. the upper pouch. This occasionally allows for primary anastomosis to be performed. Occasionally, when the two ends cannot be brought safely together, esophageal replacement is required using either a gastric pull-up or colon interposition (see the following section).Outcome. Various classification systems have been utilized to predict survival in patients with EA-TEF and to stratify treat-ment. A system devised by Waterston in 1962 was used to strat-ify neonates based on birth weight, the presence of pneumonia, and the identification of other congenital anomalies. In response to advances in neonatal care, the surgeons from the Montreal Children’s Hospital proposed a new classification system in 1993. In the Montreal experience only two characteristics inde-pendently affected survival: preoperative ventilator dependence and associated major anomalies. Pulmonary disease as defined by ventilator dependence appeared to be more accurate than pneumonia. When the two systems were compared,


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Surgery_Schwartz. ventilator dependence and associated major anomalies. Pulmonary disease as defined by ventilator dependence appeared to be more accurate than pneumonia. When the two systems were compared, the Montreal system more accurately identified children at highest risk. Spitz and colleagues analyzed risk factors in infants who died with EA-TEF. Two criteria were found to be important predictors of outcome: birth weight less than 1500 g and the presence of major congenital cardiac disease. A new classification for predicting outcome in esophageal atresia was therefore proposed: group I: birth weight ≥1500 g, without major cardiac disease, survival 97% (283 of 293); group II: birth weight <1500 g, or major car-diac disease, survival 59% (41 of 70); and group III: birth weight <1500 g, and major cardiac disease, survival 22% (2 of 9).In general, surgical correction of EA-TEF leads to a sat-isfactory outcome with nearly normal esophageal function in most patients. Overall survival rates of greater


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Surgery_Schwartz. disease, survival 22% (2 of 9).In general, surgical correction of EA-TEF leads to a sat-isfactory outcome with nearly normal esophageal function in most patients. Overall survival rates of greater than 90% have been achieved in patients classified as stable, in all the various staging systems. Unstable infants have an increased mortality (40–60% survival) because of potentially fatal associated cardiac and chromosomal anomalies or prematurity. However, the use of a staged procedure also has increased survival in even these high-risk infants.Corrosive Injury of the EsophagusInjury to the esophagus after ingestion of corrosive substances most commonly occurs in the toddler age group. Both strong alkali and strong acids produce injury by liquefaction or coag-ulation necrosis, and since all corrosive agents are extremely hygroscopic, the caustic substance will cling to the esophageal epithelium. Subsequent strictures occur at the anatomic nar-rowed areas of the esophagus, cricopharyngeus,


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Surgery_Schwartz. agents are extremely hygroscopic, the caustic substance will cling to the esophageal epithelium. Subsequent strictures occur at the anatomic nar-rowed areas of the esophagus, cricopharyngeus, midesophagus, and gastroesophageal junction. A child who has swallowed an injurious substance may be symptom-free but usually will be drooling and unable to swallow saliva. The injury may be restricted to the oropharynx and esophagus, or it may extend to include the stomach. There is no effective immediate anti-dote. Diagnosis is by careful physical examination of the mouth and endoscopy with a flexible or a rigid esophagoscope. It is important to endoscope only to the first level of the burn in order to avoid perforation. Early barium swallow may delineate the extent of the mucosal injury. It is important to realize that the esophagus may be burned without evidence of injury to the mouth. Although previously used routinely, steroids have not been shown to alter stricture development or modify


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Surgery_Schwartz. to realize that the esophagus may be burned without evidence of injury to the mouth. Although previously used routinely, steroids have not been shown to alter stricture development or modify the extent of injury and are no longer part of the management of caustic injuries. Antibiotics are administered during the acute period.The extent of injury is graded endoscopically as either mild, moderate, or severe (grade I, II, or III). Circumferential esophageal injuries with necrosis have an extremely high like-lihood of stricture formation. These patients should undergo placement of a gastrostomy tube once clinically stable. A string should be inserted through the esophagus either immediately or during repeat esophagoscopy several weeks later. When estab-lished strictures are present (usually 3 to 4 weeks), dilatation is performed. Fluoroscopically guided balloon dilation of the stric-ture is effective, which should be performed in association with esophagoscopy, and allows for a precise


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Surgery_Schwartz. 3 to 4 weeks), dilatation is performed. Fluoroscopically guided balloon dilation of the stric-ture is effective, which should be performed in association with esophagoscopy, and allows for a precise evaluation of the nature and extent of the stenosis. The procedure should be performed under general anesthesia, and care must be taken to ensure there is no airway injury. Dislodgment of the endotracheal tube can occur during this procedure, and careful communication with the anesthesiologist is critical during the procedure.In certain circumstances, especially if a gastrostomy tube has been placed, retrograde dilatation may be performed, using graduated dilators brought through the gastrostomy and advanced into the esophagus via the transesophageal string. Management of esophageal perforation during dilation should include antibiotics, irrigation, and closed drainage of the tho-racic cavity to prevent systemic sepsis. When recognition is delayed or if the patient is systemically ill,


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Surgery_Schwartz. during dilation should include antibiotics, irrigation, and closed drainage of the tho-racic cavity to prevent systemic sepsis. When recognition is delayed or if the patient is systemically ill, esophageal diver-sion may be required with staged reconstruction at a later time.Although the native esophagus can be preserved in most cases, severe stricture formation that does not respond to dila-tion is best managed by esophageal replacement. The most com-monly used options for esophageal substitution are the colon (right colon or transverse/left colon) and the stomach (gastric tubes or gastric pull-up). Pedicled or free grafts of the jejunum are rarely used. The right colon is based on a pedicle of the middle colic artery, and the left colon is based on a pedicle of the middle colic or left colic artery. Gastric tubes are fashioned from the greater curvature of the stomach based on the pedi-cle of the left gastroepiploic artery. When the entire stomach is used, as in gastric pull-up, the


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Surgery_Schwartz. artery. Gastric tubes are fashioned from the greater curvature of the stomach based on the pedi-cle of the left gastroepiploic artery. When the entire stomach is used, as in gastric pull-up, the blood supply is provided by the right gastric artery. The neoesophagus may traverse (a) sub-sternally; (b) through a transthoracic route; or (c) through the posterior mediastinum to reach the neck. A feeding jejunostomy is placed at the time of surgery and tube feedings are instituted once the postoperative ileus has resolved. Long-term follow-up has shown that all methods of esophageal substitution can sup-port normal growth and development, and the children enjoy reasonably normal eating habits. Because of the potential for late complications such as ulceration and stricture, follow-up into adulthood is mandatory, but complications appear to dimin-ish with time.Gastroesophageal RefluxGastroesophageal reflux (GER) occurs to some degree in all children and refers to the passage of gastric


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Surgery_Schwartz. adulthood is mandatory, but complications appear to dimin-ish with time.Gastroesophageal RefluxGastroesophageal reflux (GER) occurs to some degree in all children and refers to the passage of gastric contents into the esophagus. By contrast, gastroesophageal reflux disease (GERD) describes the situation where reflux is symptomatic. Typical symptoms include failure to thrive, bleeding, stricture formation, reactive airway disease, aspiration pneumonia, or apnea. Failure to thrive and pulmonary problems are particularly common in infants with GERD, whereas strictures and esopha-gitis are more common in older children and adolescents. GERD is particularly problematic in neurologically impaired children.Clinical Manifestations. Because all infants experience occasional episodes of GER to some degree, care must be taken Brunicardi_Ch39_p1705-p1758.indd 172112/02/19 11:26 AM 1722SPECIFIC CONSIDERATIONSPART IIbefore a child is labeled as having pathologic reflux. A history of repeated


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Surgery_Schwartz. degree, care must be taken Brunicardi_Ch39_p1705-p1758.indd 172112/02/19 11:26 AM 1722SPECIFIC CONSIDERATIONSPART IIbefore a child is labeled as having pathologic reflux. A history of repeated episodes of vomiting that interferes with growth and development, or the presence of apparent life-threatening events, are required for the diagnosis of GERD. In older chil-dren, esophageal bleeding, stricture formation, severe heartburn, or the development of Barrett’s esophagus unequivocally con-note pathologic reflux or GERD. In neurologically impaired children, vomiting due to GER must be distinguished from chronic retching.The workup of patients suspected of having GERD includes documentation of the episodes of reflux and evalua-tion of the anatomy. A barium swallow should be performed as an initial test. This will determine whether there is obstruction of the stomach or duodenum (due to duodenal webs or pyloric stenosis) and will determine whether malrotation is present. The frequency


Surgery_Schwartz

Surgery_Schwartz. initial test. This will determine whether there is obstruction of the stomach or duodenum (due to duodenal webs or pyloric stenosis) and will determine whether malrotation is present. The frequency and severity of reflux should be assessed using a 24-hour pH probe study. Although this test is poorly tolerated, it provides the most accurate determination that GERD is present. Esophageal endoscopy with biopsies may identify the presence of esophagitis, and it is useful to determine the length of intra-abdominal esophagus and the presence of Barrett’s esophagus. Some surgeons obtain a radioisotope “milk scan” to evaluate gastric emptying, although there is little evidence to show that this test changes management when a diagnosis of GERD has been confirmed using the aforementioned modalities.Treatment. Most patients with GERD are treated initially by conservative means. In the infant, propping and thickening the formula with rice cereal are generally recommended. Some authors prefer a


Surgery_Schwartz

Surgery_Schwartz. patients with GERD are treated initially by conservative means. In the infant, propping and thickening the formula with rice cereal are generally recommended. Some authors prefer a prone, head-up position. In the infant unrespon-sive to position and formula changes and the older child with severe GERD, medical therapy is based on gastric acid reduc-tion with an H2-blocking agent and/or a proton pump inhibitor. Medical therapy is successful in most neurologically normal infants and younger children, many of whom will outgrow their need for medications. In certain patients, however, medical treatment does not provide symptomatic relief and surgery is therefore indicated. The least invasive surgical option includes the placement of a nasojejunal or gastrojejunal feeding tube. Because the stomach is bypassed, food contents do not enter the esophagus, and symptoms are often improved. However, as a long-term remedy, this therapy is associated with several problems. The tubes often become


Surgery_Schwartz

Surgery_Schwartz. is bypassed, food contents do not enter the esophagus, and symptoms are often improved. However, as a long-term remedy, this therapy is associated with several problems. The tubes often become dislodged, acid reflux still occurs, and bolus feeding is generally not possible. Fundoplica-tion provides definitive treatment for gastroesophageal reflux and is highly effective in most circumstances. The fundus may be wrapped around the distal esophagus either 360o (i.e., Nissen) or to lesser degrees (i.e., Thal or Toupet). At present, the stan-dard approach in most children is to perform these procedures laparoscopically whenever possible. In children with feeding difficulties and in infants under 1 year of age, a gastrostomy tube should be placed at the time of surgery. Early postoperative complications include pneumonia and atelectasis, often due to inadequate pulmonary toilet and pain control with abdominal splinting. Late postoperative complications include wrap break-down with


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Surgery_Schwartz. complications include pneumonia and atelectasis, often due to inadequate pulmonary toilet and pain control with abdominal splinting. Late postoperative complications include wrap break-down with recurrent reflux, which may require repeat fundo-plication, and dysphagia due to a wrap performed too tightly, which generally responds to dilation. These complications are more common in children with neurologic impairment. The keys to successful surgical management of patients with GERD include careful patient selection and meticulous operative tech-nique. There are emerging concerns regarding the long-term use of acid reducing agents, which may increase the frequency with which antireflux procedures are performed in children, espe-cially those with neurological impairment.GASTROINTESTINAL TRACTAn Approach to the Vomiting InfantAll infants vomit. Because infant vomiting is so common, it is important to differentiate between normal and abnormal vomit-ing, which may be indicative of a


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Surgery_Schwartz. TRACTAn Approach to the Vomiting InfantAll infants vomit. Because infant vomiting is so common, it is important to differentiate between normal and abnormal vomit-ing, which may be indicative of a potentially serious underlying disorder. In order to determine the seriousness of a particular infant’s bouts of emesis, one needs to characterize what the vomit looks like and how sick the baby is. Vomit that looks like feeds and comes up immediately after a feeding is almost always gastroesophageal reflux. This may or may not be of concern, as described earlier. Vomiting that occurs a short while after feed-ing, or vomiting that projects out of the baby’s mouth may be indicative of pyloric stenosis. By contrast, vomit that has any green color in it is always worrisome. This may be reflective of intestinal volvulus, an underlying infection, or some other cause of intestinal obstruction. A more detailed description of the management of these conditions is provided in the follow-ing


Surgery_Schwartz

Surgery_Schwartz. of intestinal volvulus, an underlying infection, or some other cause of intestinal obstruction. A more detailed description of the management of these conditions is provided in the follow-ing sections.Hypertrophic Pyloric StenosisClinical Presentation. Infants with hypertrophic pyloric stenosis (HPS) typically present with nonbilious vomiting that becomes increasingly projectile, over the course of several days to weeks due to progressive thickening of the pylorus muscle. HPS occurs in approximately 1 in 300 live births and commonly in infants between 3 and 6 weeks of age. Male-to-female ratio is nearly 5:1.Eventually as the pyloric muscle thickening progresses, the infant develops a complete gastric outlet obstruction and is no longer able to tolerate any feeds. Over time, the infant becomes increasingly hungry, unsuccessfully feeds repeatedly, and becomes increasingly dehydrated. Wet diapers become less frequent, and there may even be a perception of less passage of flatus. HPS may


Surgery_Schwartz

Surgery_Schwartz. increasingly hungry, unsuccessfully feeds repeatedly, and becomes increasingly dehydrated. Wet diapers become less frequent, and there may even be a perception of less passage of flatus. HPS may be associated with jaundice due to an indi-rect hyperbilirubinemia, although the nature of this relation is unclear.The cause of HPS has not been determined. Studies have shown that HPS is found in several generations of the same family, suggesting a familial link. Recently, a genome-wide sig-nificant locus for pyloric stenosis at chromosome 11q23.3 was identified, and the single-nucleotide polymorphism (SNP) with the greatest significance was associated with part of the genome that regulates cholesterol. It is not clear how this links to the development of pyloric stenosis, but it does suggest a potential dietary link.Infants with HPS develop a hypochloremic, hypokale-mic metabolic alkalosis. The urine pH level is high initially, but eventually drops because hydrogen ions are preferentially


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Surgery_Schwartz. potential dietary link.Infants with HPS develop a hypochloremic, hypokale-mic metabolic alkalosis. The urine pH level is high initially, but eventually drops because hydrogen ions are preferentially exchanged for sodium ions in the distal tubule of the kidney as the hypochloremia becomes severe (paradoxical aciduria). While in the past the diagnosis of pyloric stenosis was most often made on physical examination by palpation of the typical “olive” in the right upper quadrant and the presence of visible gastric waves on the abdomen, current standard of care is to perform an US, which can diagnose the condition accurately in 95% of patients. Criteria for US diagnosis include a channel length of over 16 mm and pyloric thickness over 4 mm. It is important to note that younger babies may have lower values Brunicardi_Ch39_p1705-p1758.indd 172212/02/19 11:26 AM 1723PEDIATRIC SURGERYCHAPTER 39Pyloric “tumor”MucosaABCFigure 39-12. Fredet-Ramstedt pyloromyotomy. A. Pylorus deliv-ered into


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Surgery_Schwartz. lower values Brunicardi_Ch39_p1705-p1758.indd 172212/02/19 11:26 AM 1723PEDIATRIC SURGERYCHAPTER 39Pyloric “tumor”MucosaABCFigure 39-12. Fredet-Ramstedt pyloromyotomy. A. Pylorus deliv-ered into wound and seromuscular layer incised. B. Seromuscular layer separated down to submucosal base to permit herniation of mucosa through pyloric incision. C. Cross-section demonstrating hypertrophied pylorus, depth of incision, and spreading of muscle to permit mucosa to herniate through incision.for pyloric thickness and still be abnormal, and a close clinical correlation with the US result is mandatory. In cases in which the diagnosis remains unclear, upper gastrointestinal evaluation by contrast radiography will reveal delayed passage of contents from the stomach through the pyloric channel and a typical thickened appearance to the pylorus.Treatment. Given frequent fluid and electrolyte abnormali-ties at time of presentation, pyloric stenosis is never a surgical emergency. Fluid


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Surgery_Schwartz. channel and a typical thickened appearance to the pylorus.Treatment. Given frequent fluid and electrolyte abnormali-ties at time of presentation, pyloric stenosis is never a surgical emergency. Fluid resuscitation with correction of electrolyte abnormalities and metabolic alkalosis is essential prior to induc-tion of general anesthesia for operation. For most infants, fluid containing 5% dextrose and 0.45% saline with added potassium of 2 to 4 mEq/kg over 24 hours at a rate of approximately 150 to 175 mL/kg for 24 hours will correct the underlying deficit. It is important to ensure that the child has an adequate urine output (>2 cc/kg per hour) as further evidence that rehydration has occurred.After resuscitation, a Fredet-Ramstedt pyloromyotomy is performed (Fig. 39-12). It may be performed using an open or laparoscopic approach. The open pyloromyotomy is per-formed through either an umbilical or a right upper quadrant transverse abdominal incision. The former route is cosmetically


Surgery_Schwartz

Surgery_Schwartz. using an open or laparoscopic approach. The open pyloromyotomy is per-formed through either an umbilical or a right upper quadrant transverse abdominal incision. The former route is cosmetically more appealing, although the transverse incision provides easier access to the antrum and pylorus. In recent years, the laparo-scopic approach has gained great popularity. Two randomized trials have demonstrated that both the open and laparoscopic approaches may be performed safely with equal incidence of postoperative complications, although the cosmetic result is clearly superior with the laparoscopic approach. Whether done through an open or laparoscopic approach, surgical treatment of pyloric stenosis involves splitting the pyloric muscle while leav-ing the underlying submucosa intact. The incision extends from just proximal to the pyloric vein of Mayo to the gastric antrum; it typically measures between 1 and 2 cm in length. Postop-eratively, IV fluids are continued for several hours,


Surgery_Schwartz

Surgery_Schwartz. incision extends from just proximal to the pyloric vein of Mayo to the gastric antrum; it typically measures between 1 and 2 cm in length. Postop-eratively, IV fluids are continued for several hours, after which Pedialyte is offered, followed by formula or breast milk, which is gradually increased to 60 cc every 3 hours. Most infants can be discharged home within 24 to 48 hours following surgery. Recently, several authors have shown that ad lib feeds are safely tolerated by the neonate and result in a shorter hospital stay.The complications of pyloromyotomy include perforation of the mucosa (1–3%), bleeding, wound infection, and recur-rent symptoms due to inadequate myotomy. When perforation occurs, the mucosa is repaired with a stitch that is placed to tack the mucosa down and reapproximate the serosa in the region of the tear. A nasogastric tube is left in place for 24 hours. The outcome is generally very good.Intestinal Obstruction in the NewbornThe cardinal symptom of intestinal


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Surgery_Schwartz. the serosa in the region of the tear. A nasogastric tube is left in place for 24 hours. The outcome is generally very good.Intestinal Obstruction in the NewbornThe cardinal symptom of intestinal obstruction in the newborn is bilious emesis. Prompt recognition and treatment of neonatal intestinal obstruction can truly be lifesaving.The incidence of neonatal intestinal obstruction is 1 in 2000 live births. The approach to intestinal obstruction in the newborn infant is critical for timely and appropriate interven-tion. When a neonate develops bilious vomiting, one must con-sider a surgical etiology. Indeed, the majority of newborns with bilious emesis have a surgical condition. In evaluating a poten-tial intestinal obstruction, it is helpful to determine whether the intestinal obstruction is either proximal or distal to the ligament of Treitz. One must conduct a detailed prenatal and immediate postnatal history and a thorough physical examination. In all cases of intestinal


Surgery_Schwartz

Surgery_Schwartz. is either proximal or distal to the ligament of Treitz. One must conduct a detailed prenatal and immediate postnatal history and a thorough physical examination. In all cases of intestinal obstruction, it is vital to obtain abdominal films in the supine and upright (or lateral decubitus) views to assess the presence of air-fluid levels or free air as well as how far downstream air has managed to travel. Importantly, one should recognize that it is difficult to determine whether a loop of bowel is part of either the small or large intestine, as neonatal bowel lacks clear features, such as haustra or plica circulares, normally present in older children or adults. As such, contrast imaging may be necessary for diagnosis in some instances.Proximal intestinal obstructions typically present with bil-ious emesis and minimal abdominal distention. The normal neo-nate should have a rounded, soft abdomen; in contrast, a neonate with a proximal intestinal obstruction typically exhibits a flat or


Surgery_Schwartz

Surgery_Schwartz. bil-ious emesis and minimal abdominal distention. The normal neo-nate should have a rounded, soft abdomen; in contrast, a neonate with a proximal intestinal obstruction typically exhibits a flat or scaphoid abdomen. On a series of upright and supine abdominal radiographs, one may see a paucity or absence of bowel gas, which normally should be present throughout the gastrointesti-nal tract within 24 hours. Of utmost importance is the exclusion of a malrotation with midgut volvulus from all other intestinal obstructions as this is a surgical emergency.Distal obstructions typically present with bilious emesis and abdominal distention. Passage of black-green meconium should have occurred within the first 24 to 38 hours. Of great 34Brunicardi_Ch39_p1705-p1758.indd 172312/02/19 11:26 AM 1724SPECIFIC CONSIDERATIONSPART IIFigure 39-13. Abdominal X-ray showing “double bubble” sign in a newborn infant with duodenal atresia. The two “bubbles” are numbered.importance, one should determine


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Surgery_Schwartz. 1724SPECIFIC CONSIDERATIONSPART IIFigure 39-13. Abdominal X-ray showing “double bubble” sign in a newborn infant with duodenal atresia. The two “bubbles” are numbered.importance, one should determine whether there is tenderness or discoloration of the abdomen, visible or palpable loops of intestine, presence or absence of a mass, and whether the anus is patent and in appropriate location. Abdominal radiographs may demonstrate calcifications may indicate complicated meconium ileus; pneumatosis and/or pneumoperitoneum may indicate necrotizing enterocolitis. A contrast enema may show whether there is a microcolon indicative of jejunoileal atresia or meconium ileus. If a microcolon is not present, then the diag-noses of Hirschsprung’s disease, small left colon syndrome, or meconium plug syndrome should be considered.Duodenal ObstructionWhenever the diagnosis of duodenal obstruction is entertained, malrotation and midgut volvulus must be excluded. This topic is covered in further detail


Surgery_Schwartz

Surgery_Schwartz. should be considered.Duodenal ObstructionWhenever the diagnosis of duodenal obstruction is entertained, malrotation and midgut volvulus must be excluded. This topic is covered in further detail later in this chapter. Other causes of duodenal obstruction include duodenal atresia, duodenal web, stenosis, annular pancreas, or duodenal duplication cyst. Duode-nal obstruction is easily diagnosed on prenatal US, which dem-onstrates the fluid-filled stomach and proximal duodenum as two discrete cystic structures in the upper abdomen. Associated polyhydramnios is common and presents in the third trimester. In 85% of infants with duodenal obstruction, the entry of the bile duct is proximal to the level of obstruction, such that vom-iting is bilious. Abdominal distention is typically not present because of the proximal level of obstruction. In those infants with obstruction proximal to the bile duct entry, the vomiting is nonbilious. The classic finding on abdominal radiography is the “double


Surgery_Schwartz

Surgery_Schwartz. of the proximal level of obstruction. In those infants with obstruction proximal to the bile duct entry, the vomiting is nonbilious. The classic finding on abdominal radiography is the “double bubble” sign, which represents the dilated stomach and duodenum (Fig. 39-13). In association with the appropriate clin-ical picture, this finding is sufficient to confirm the diagnosis of duodenal obstruction. However, if there is any uncertainty, particularly when a partial obstruction is suspected, a contrast upper gastrointestinal series is diagnostic.Treatment. An orogastric tube is inserted to decompress the stomach and duodenum and the infant is given IV fluids to maintain adequate urine output. If the infant appears ill, or if abdominal tenderness is present, a diagnosis of malrotation and midgut volvulus should be considered, and surgery should not be delayed. Typically, the abdomen is soft, and the infant is very stable. Under these circumstances, the infant should be evaluated


Surgery_Schwartz

Surgery_Schwartz. and midgut volvulus should be considered, and surgery should not be delayed. Typically, the abdomen is soft, and the infant is very stable. Under these circumstances, the infant should be evaluated thoroughly for other associated anomalies. Approxi-mately one-third of newborns with duodenal atresia have asso-ciated Down syndrome (trisomy 21). These patients should be evaluated for associated cardiac anomalies. Once the workup is complete and the infant is stable, he or she is taken to the operat-ing room, and repair is performed either via an open approach or laparoscopically.Regardless of the surgical approach, the principles are the same. If open, the abdomen is entered through a transverse right upper quadrant supraumbilical incision under general endotra-cheal anesthesia. Associated anomalies should be searched for at the time of the operation. These include malrotation, ante-rior portal vein, a second distal web, and biliary atresia. The surgical treatment of choice for duodenal


Surgery_Schwartz

Surgery_Schwartz. should be searched for at the time of the operation. These include malrotation, ante-rior portal vein, a second distal web, and biliary atresia. The surgical treatment of choice for duodenal obstruction due to duodenal stenosis or atresia or annular pancreas is a duodeno-duodenostomy. This procedure can be most easily performed using a proximal transverse-to-distal longitudinal (diamond-shaped) anastomosis. In cases where the duodenum is extremely dilated, the lumen may be tapered using a linear stapler with a large Foley catheter (24F or greater) in the duodenal lumen. It is important to emphasize that an annular pancreas is never divided but rather is bypassed to avoid injury to the pancreatic ducts. Treatment of duodenal web includes vertical duodenot-omy, excision of the web, oversewing of the mucosa, and clos-ing the duodenotomy horizontally. Care must be taken to avoid injury to the bile duct, which opens up near the web in all cases. For this reason, some surgeons favor


Surgery_Schwartz

Surgery_Schwartz. of the mucosa, and clos-ing the duodenotomy horizontally. Care must be taken to avoid injury to the bile duct, which opens up near the web in all cases. For this reason, some surgeons favor performing a duodeno-duodenostomy for children with duodenal web, although such an approach may lead to long-term complications associated with the creation of a blind section of duodenum between the web and the bypass, which can expand over time. Gastrostomy tube placement is not routinely performed. Recently reported survival rates exceed 90%. Late complications from repair of duodenal atresia occur in approximately 12% to 15% of patients and include megaduodenum, intestinal motility disorders, and gastroesophageal reflux.Specific consideration may be given to premature infants with duodenal obstruction. Whereas in the past pediatric sur-geons may have favored delayed repair until the child reached either term or a weight closer to 3 kg, there is no reason to wait, and once the child is stable


Surgery_Schwartz

Surgery_Schwartz. Whereas in the past pediatric sur-geons may have favored delayed repair until the child reached either term or a weight closer to 3 kg, there is no reason to wait, and once the child is stable from a pulmonary perspective, duo-denal repair can be performed in children as small as 1 kg quite safely, as long as there is meticulous attention to detail and a thorough knowledge of the anatomy.Intestinal AtresiaObstruction due to intestinal atresia can occur at any point along the intestinal tract. Intestinal atresias were previously thought to be the result of in utero mesenteric vascular accidents leading to segmental loss of the intestinal lumen, although more likely they are the result of developmental defects in normal intestinal organogenesis due to disruption of various signaling pathways such as fibroblast growth factor, bone morphogenic protein, and β-catenin pathways. The incidence of intestinal atresia has been estimated to be between 1 in 2000 to 1 in 5000 live births, with


Surgery_Schwartz

Surgery_Schwartz. such as fibroblast growth factor, bone morphogenic protein, and β-catenin pathways. The incidence of intestinal atresia has been estimated to be between 1 in 2000 to 1 in 5000 live births, with equal representation of the sexes. Infants with jejunal or ileal atresia present with bilious vomiting and progressive abdominal distention. The more distal the obstruction, the more distended the abdomen becomes, and the greater the number of obstructed loops on upright abdominal films (Fig. 39-14).In cases where the diagnosis of complete intestinal obstruction is ascertained by the clinical picture and the pres-ence of staggered air-fluid levels on plain abdominal films, the child can be brought to the operating room after appropriate resuscitation. In these circumstances, there is little extra infor-mation to be gained by performing a barium enema. By contrast, Brunicardi_Ch39_p1705-p1758.indd 172412/02/19 11:26 AM 1725PEDIATRIC SURGERYCHAPTER 39Figure 39-14. Intestinal obstruction in


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Surgery_Schwartz. infor-mation to be gained by performing a barium enema. By contrast, Brunicardi_Ch39_p1705-p1758.indd 172412/02/19 11:26 AM 1725PEDIATRIC SURGERYCHAPTER 39Figure 39-14. Intestinal obstruction in the newborn showing sev-eral loops of distended bowel with air fluid levels. This child has jejunal atresia.Figure 39-15. Operative photograph of newborn with “Christmas tree” type of ileal atresia.when there is diagnostic uncertainty, or when distal intestinal obstruction is apparent, a barium enema is useful to establish whether a microcolon is present and to diagnose the presence of meconium plugs, small left colon syndrome, Hirschsprung’s disease, or meconium ileus. Judicious use of barium enema is therefore required in order to safely manage neonatal intestinal obstruction, based on an understanding of the expected level of obstruction.Surgical correction of the small intestinal atresia should be performed relatively urgently, especially when there is a possibility of volvulus. At


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Surgery_Schwartz. understanding of the expected level of obstruction.Surgical correction of the small intestinal atresia should be performed relatively urgently, especially when there is a possibility of volvulus. At laparotomy, one of several types of atresia will be encountered. In type 1 there is a mucosal atre-sia with intact muscularis. In type 2, the atretric ends are con-nected by a fibrous band. In type 3A, the two ends of the atresia are separated by a V-shaped defect in the mesentery. Type 3B is an “apple-peel” deformity or “Christmas tree” deformity in which the bowel distal to the atresia receives its blood supply in a retrograde fashion from the ileocolic or right colic artery (Fig. 39-15). In type 4 atresia, there are multiple atresias with a “string of sausage” or “string of beads” appearance. Disparity in lumen size between the proximal distended bowel and the small diameter of collapsed bowel distal to the atresia has led to a num-ber of innovative techniques of anastomosis. However,


Surgery_Schwartz

Surgery_Schwartz. Disparity in lumen size between the proximal distended bowel and the small diameter of collapsed bowel distal to the atresia has led to a num-ber of innovative techniques of anastomosis. However, under most circumstances, an anastomosis can be performed using the end-to-back technique in which the distal, compressed loop is “fish-mouthed” along its antimesenteric border. The proximal distended loop can be tapered as previously described. Because the distended proximal bowel rarely has normal motility, the extremely dilated portion should be resected prior to per-forming the anastomosis.Occasionally the infant with intestinal atresia will develop ischemia or necrosis of the proximal segment secondary to volvulus of the dilated, bulbous, blind-ending proximal bowel. Under these conditions, primary anastomosis may be performed as described earlier. Alternatively, an end ileostomy and mucus fistula should be created, and the anastomosis should be deferred to another time after the infant


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Surgery_Schwartz. primary anastomosis may be performed as described earlier. Alternatively, an end ileostomy and mucus fistula should be created, and the anastomosis should be deferred to another time after the infant stabilizes.Malrotation and Midgut VolvulusEmbryology. During the sixth week of fetal development, the midgut grows too rapidly to be accommodated in the abdominal cavity and therefore herniates into the umbilical cord. Between the 10th and 12th week, the midgut returns to the abdominal cavity, undergoing a 270° counterclockwise rotation around the superior mesenteric artery. Because the duodenum also rotates caudal to the artery, it acquires a C-loop, which traces this path. The cecum rotates cephalad to the artery, which determines the location of the transverse and ascending colon. Subsequently, the duodenum becomes fixed retroperitoneally in its third por-tion and at the ligament of Treitz, while the cecum becomes fixed to the lateral abdominal wall by peritoneal bands. The takeoff of


Surgery_Schwartz

Surgery_Schwartz. the duodenum becomes fixed retroperitoneally in its third por-tion and at the ligament of Treitz, while the cecum becomes fixed to the lateral abdominal wall by peritoneal bands. The takeoff of the branches of the superior mesenteric artery elon-gates and becomes fixed along a line extending from its emer-gence from the aorta to the cecum in the right lower quadrant. Genetic mutations likely disrupt the signaling critical for normal intestinal rotation. For instance, mutations in the gene BCL6 resulting in absence of left-sided expression of its transcript lead to reversed cardiac orientation, defective ocular development, and malrotation. The essential role of the dorsal gut mesentery in mediating normal intestinal rotation and the role of the fork-head box transcription factor FOXF1 in formation of the dorsal mesentery in mice are consistent with the noted association of intestinal malrotation with alveolar capillary dysplasia, caused by mutations in FOXF1. If rotation is


Surgery_Schwartz

Surgery_Schwartz. FOXF1 in formation of the dorsal mesentery in mice are consistent with the noted association of intestinal malrotation with alveolar capillary dysplasia, caused by mutations in FOXF1. If rotation is incomplete, the cecum remains in the epigastrium, but the bands fixing the duode-num to the retroperitoneum and cecum continue to form. This results in (Ladd’s) bands extending from the cecum to the lat-eral abdominal wall and crossing the duodenum, which creates the potential for obstruction. The mesenteric takeoff remains confined to the epigastrium, resulting in a narrow pedicle sus-pending all the branches of the superior mesenteric artery and the entire midgut. A volvulus may therefore occur around the mesentery. This twist not only obstructs the proximal jejunum but also cuts off the blood supply to the midgut. Intestinal obstruction and complete infarction of the midgut occur unless the problem is promptly corrected surgically.Presentation and Management. Midgut volvulus can occur


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Surgery_Schwartz. supply to the midgut. Intestinal obstruction and complete infarction of the midgut occur unless the problem is promptly corrected surgically.Presentation and Management. Midgut volvulus can occur at any age, though it is seen most often in the first few weeks of life. Bilious vomiting is usually the first sign of volvulus and all infants with bilious vomiting must be evaluated rapidly to ensure that they do not have intestinal malrotation with volvu-lus. The child with irritability and bilious emesis should raise particular suspicions for this diagnosis. If left untreated, vascular Brunicardi_Ch39_p1705-p1758.indd 172512/02/19 11:26 AM 1726SPECIFIC CONSIDERATIONSPART IIFigure 39-16. Abdominal X-ray of a 10-day-old infant with bil-ious emesis. Note the dilated proximal bowel and the paucity of distal bowel gas, characteristic of a volvulus.compromise of the midgut initially causes bloody stools, but it eventually results in circulatory collapse. Additional clues to the presence of


Surgery_Schwartz

Surgery_Schwartz. of distal bowel gas, characteristic of a volvulus.compromise of the midgut initially causes bloody stools, but it eventually results in circulatory collapse. Additional clues to the presence of advanced ischemia of the intestine include ery-thema and edema of the abdominal wall, which progresses to shock and death. It must be reemphasized that the index of sus-picion for this condition must be high, since abdominal signs are minimal in the early stages. Abdominal films show a paucity of gas throughout the intestine with a few scattered air-fluid levels (Fig. 39-16). When these findings are present, the patient should undergo immediate fluid resuscitation to ensure adequate per-fusion and urine output followed by prompt exploratory lapa-rotomy. In cases where the child is stable, laparoscopy may be considered.Often the patient will not appear ill, and the plain films may suggest partial duodenal obstruction. Under these condi-tions, the patient may have malrotation without volvulus.


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Surgery_Schwartz. may be considered.Often the patient will not appear ill, and the plain films may suggest partial duodenal obstruction. Under these condi-tions, the patient may have malrotation without volvulus. This is best diagnosed by an upper gastrointestinal series that shows incomplete rotation with the duodenojejunal junction displaced to the right. The duodenum may show a corkscrew effect diag-nosing volvulus, or complete duodenal obstruction, with the small bowel loops entirely in the right side of the abdomen. Barium enema may show a displaced cecum, but this sign is unreliable, especially in the small infant in whom the cecum is normally in a somewhat higher position than in the older child.When volvulus is suspected, early surgical intervention is mandatory if the ischemic process is to be avoided or reversed. Volvulus occurs clockwise, and it is therefore untwisted coun-terclockwise. This can be remembered using the memory aid “turn back the hands of time.” Subsequently, a Ladd’s


Surgery_Schwartz

Surgery_Schwartz. be avoided or reversed. Volvulus occurs clockwise, and it is therefore untwisted coun-terclockwise. This can be remembered using the memory aid “turn back the hands of time.” Subsequently, a Ladd’s proce-dure is performed. This operation does not correct the malro-tation, but it does broaden the narrow mesenteric pedicle to prevent volvulus from recurring. This procedure is performed as follows (Fig. 39-17). The bands between the cecum and the abdominal wall and between the duodenum and terminal ileum are divided sharply to splay out the superior mesenteric artery and its branches. This maneuver brings the straightened duodenum into the right lower quadrant and the cecum into the left lower quadrant. The appendix is usually removed to avoid diagnostic errors in later life. No attempt is made to suture the cecum or duodenum in place. With advanced ischemia, reduc-tion of the volvulus without the Ladd’s procedure is accom-plished, and a “second look” 24 to 36 hours later often may show


Surgery_Schwartz

Surgery_Schwartz. to suture the cecum or duodenum in place. With advanced ischemia, reduc-tion of the volvulus without the Ladd’s procedure is accom-plished, and a “second look” 24 to 36 hours later often may show some vascular recovery. A plastic transparent silo may be placed to facilitate constant evaluation of the intestine and to plan for the timing of reexploration. Clearly necrotic bowel can then be resected conservatively. With early diagnosis and cor-rection, the prognosis is excellent. However, diagnostic delay can lead to mortality or to short-gut syndrome requiring intes-tinal transplantation.A subset of patients with malrotation will demonstrate chronic obstructive symptoms. These symptoms may result from Ladd’s bands across the duodenum, or occasionally, from intermittent volvulus. Symptoms include intermittent abdominal pain and intermittent vomiting that may occasionally be bilious. Infants with malrotation may demonstrate failure to thrive, and they may be diagnosed initially as having


Surgery_Schwartz

Surgery_Schwartz. intermittent abdominal pain and intermittent vomiting that may occasionally be bilious. Infants with malrotation may demonstrate failure to thrive, and they may be diagnosed initially as having gastroesophageal reflux disease. Surgical correction using Ladd’s procedure as described earlier can prevent volvulus from occurring and improve symp-toms in many instances. In these cases, a laparoscopic approach may be taken, where diagnosis of Ladd’s bands and direct visu-alization of the relevant anatomy may be achieved.Meconium IleusPathogenesis and Clinical Presentation. Infants with cystic fibrosis have characteristic pancreatic enzyme deficiencies and abnormal chloride secretion in the intestine that result in the production of viscous, water-poor meconium. This phenotype is explained by the presence of mutations in the CFTR gene. Meconium ileus occurs when this thick, highly viscous meco-nium becomes impacted in the ileum and leads to high-grade intestinal obstruction. Recently,


Surgery_Schwartz

Surgery_Schwartz. by the presence of mutations in the CFTR gene. Meconium ileus occurs when this thick, highly viscous meco-nium becomes impacted in the ileum and leads to high-grade intestinal obstruction. Recently, additional mutations were identified in genes encoding multiple apical plasma membrane proteins of infants with meconium ileus. Meconium ileus can be either uncomplicated, in which there is no intestinal perforation, or complicated, in which prenatal perforation of the intestine has occurred or vascular compromise of the distended ileum devel-ops. Antenatal US may reveal the presence of intra-abdominal or scrotal calcifications, or distended bowel loops. These infants present shortly after birth with progressive abdominal disten-tion and failure to pass meconium with intermittent bilious emesis. Abdominal radiographs show dilated loops of intestine. Because the enteric contents are so viscous, air-fluid levels do not form, even when obstruction is complete. Small bubbles of gas become


Surgery_Schwartz

Surgery_Schwartz. Abdominal radiographs show dilated loops of intestine. Because the enteric contents are so viscous, air-fluid levels do not form, even when obstruction is complete. Small bubbles of gas become entrapped in the inspissated meconium in the dis-tal ileum, where they produce a characteristic “ground glass” appearance.The diagnosis of meconium ileus is confirmed by a con-trast enema that typically demonstrates a microcolon. In patients with uncomplicated meconium ileus, the terminal ileum is filled with pellets of meconium. In patients with complicated meco-nium ileus, intraperitoneal calcifications form, producing an eggshell pattern on plain abdominal X-ray.Management. The treatment strategy depends on whether the patient has complicated or uncomplicated meconium ileus. Patients with uncomplicated meconium ileus can be Brunicardi_Ch39_p1705-p1758.indd 172612/02/19 11:26 AM 1727PEDIATRIC SURGERYCHAPTER 39Figure 39-17. Ladd procedure for malrotation. A. Lysis of cecal and duodenal


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Surgery_Schwartz. meconium ileus can be Brunicardi_Ch39_p1705-p1758.indd 172612/02/19 11:26 AM 1727PEDIATRIC SURGERYCHAPTER 39Figure 39-17. Ladd procedure for malrotation. A. Lysis of cecal and duodenal bands. B. Broadening the mesentery. C. Appendectomy.treated nonoperatively. Either dilute water-soluble contrast or N-acetylcysteine (Mucomyst) is infused transanally via catheter under fluoroscopic control into the dilated portion of the ileum. Because these agents act by absorbing fluid from the bowel wall into the intestinal lumen, infants undergoing treatment are at risk of fluid and electrolyte abnormalities so that appropriate resuscitation of the infant during this maneuver is extremely important. The enema may be repeated at 12-hour intervals over several days until all the meconium is evacuated. Inability to reflux the contrast into the dilated portion of the ileum signi-fies the presence of an associated atresia or complicated meco-nium ilus, and thus warrants exploratory laparotomy. If


Surgery_Schwartz

Surgery_Schwartz. Inability to reflux the contrast into the dilated portion of the ileum signi-fies the presence of an associated atresia or complicated meco-nium ilus, and thus warrants exploratory laparotomy. If surgical intervention is required because of failure of contrast enemas to relieve obstruction, operative irrigation with dilute contrast agent, N-acetylcysteine, or saline through a purse-string suture may be successful. Alternatively, resection of the distended ter-minal ileum is performed, and the meconium pellets are flushed from the distal small bowel. At this point, an end ileostomy may be created. The distal bowel may be brought up as a mucus fistula or sewn to the side of the ileum as a classic Bishop-Koop anastomosis. An end-to-end anastomosis may also be consid-ered in the appropriate setting (Fig. 39-18).Necrotizing EnterocolitisClinical Features. Necrotizing enterocolitis (NEC) is the most frequent and lethal gastrointestinal disorder affecting the intestine of the stressed,


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Surgery_Schwartz. setting (Fig. 39-18).Necrotizing EnterocolitisClinical Features. Necrotizing enterocolitis (NEC) is the most frequent and lethal gastrointestinal disorder affecting the intestine of the stressed, preterm neonate. The overall mortal-ity ranges between 10% and 50%. Advances in neonatal care such as surfactant therapy as well as improved methods of mechanical ventilation have resulted in increasing numbers of Brunicardi_Ch39_p1705-p1758.indd 172712/02/19 11:26 AM 1728SPECIFIC CONSIDERATIONSPART IIProximalDistalABCDProximalDistalProximalDistalProximalDistalDistalProximalTypical operative findingEnd to backThomas taperBishop-Koop with distal ventMikulicz enterostomyFigure 39-18. Techniques of intestinal anastomosis for infants with small bowel obstruction. A. End-to-back distal limb has been incised, creating “fishmouth” to enlarge the lumen. B. Bishop-Koop; proximal distended limb joined to side of distal small bowel, which is vented by “chimney” to the abdominal wall. C. Tapering;


Surgery_Schwartz

Surgery_Schwartz. been incised, creating “fishmouth” to enlarge the lumen. B. Bishop-Koop; proximal distended limb joined to side of distal small bowel, which is vented by “chimney” to the abdominal wall. C. Tapering; portion of antimesenteric wall of proximal bowel excised, with longitudinal closure to minimize disparity in the limbs. D. Mikulicz double-barreled enterostomy is constructed by suturing the two limbs together and then exte-riorizing the double stoma. The common wall can be crushed with a special clamp to create a large stoma. The stoma can be closed in an extraperitoneal manner.low-birth-weight infants surviving neonatal hyaline membrane disease. An increasing proportion of survivors of neonatal respi-ratory distress syndrome will therefore be at risk for developing NEC. Consequently, it is estimated that NEC may eventually surpass respiratory distress syndrome as the principal cause of death in the preterm infant. This is especially relevant, as NEC is a significant risk factor for more


Surgery_Schwartz

Surgery_Schwartz. that NEC may eventually surpass respiratory distress syndrome as the principal cause of death in the preterm infant. This is especially relevant, as NEC is a significant risk factor for more severe respiratory distress in premature infants.Multiple risk factors have been associated with the devel-opment of NEC. These include prematurity, initiation of enteral feeding, bacterial infection, intestinal ischemia resulting from birth asphyxia, umbilical artery cannulation, persistence of a patent ductus arteriosus, cyanotic heart disease, and maternal cocaine abuse. Nonetheless, the mechanisms by which these complex interacting etiologies lead to the development of the disease remain undefined. The only consistent epidemio-logic precursors for NEC are prematurity and enteral ali-mentation, representing the commonly encountered clinical situation of a stressed infant who is fed enterally. Of note, there is some debate regarding the type and strategy of enteral alimen-tation in the


Surgery_Schwartz

Surgery_Schwartz. representing the commonly encountered clinical situation of a stressed infant who is fed enterally. Of note, there is some debate regarding the type and strategy of enteral alimen-tation in the pathogenesis of NEC. A prospective randomized 5study showed no increase in the incidence of NEC despite an aggressive feeding strategy.The indigenous intestinal microbial flora has been shown to play a central role in the pathogenesis of NEC. The importance of bacteria in the pathogenesis of NEC is further supported by the finding that NEC occurs in episodic waves that can be abrogated by infection control measures, and the fact that NEC usually develops at least 10 days postnatally, when the GI tract is colonized by coliforms. More recently, outbreaks of NEC have been reported in infants fed formula contaminated with Enterobacter sakazakii. Common bacterial isolates from the blood, peritoneal fluid, and stool of infants with advanced NEC include Escherichia coli, Enterobacter, Klebsiella, and


Surgery_Schwartz

Surgery_Schwartz. contaminated with Enterobacter sakazakii. Common bacterial isolates from the blood, peritoneal fluid, and stool of infants with advanced NEC include Escherichia coli, Enterobacter, Klebsiella, and occasionally, coagulase-negative Staphylococ-cus species.NEC may involve single or multiple segments of the intes-tine, most commonly the terminal ileum, followed by the colon. The gross findings in NEC include bowel distention with patchy areas of thinning, pneumatosis, gangrene, or frank perforation. The microscopic features include the appearance of a “bland infarct” characterized by full thickness necrosis.Brunicardi_Ch39_p1705-p1758.indd 172812/02/19 11:26 AM 1729PEDIATRIC SURGERYCHAPTER 39Figure 39-19. Abdominal radiograph of infant with necrotizing enterocolitis. Arrows point to area of pneumatosis intestinalis.Clinical Manifestations. Infants with NEC present with a spectrum of disease. In general, the infants are premature and may have sustained one or more episodes of stress,


Surgery_Schwartz

Surgery_Schwartz. of pneumatosis intestinalis.Clinical Manifestations. Infants with NEC present with a spectrum of disease. In general, the infants are premature and may have sustained one or more episodes of stress, such as birth asphyxia, or they may have congenital cardiac disease. The clin-ical picture of NEC has been characterized as progressing from a period of mild illness to that of severe, life-threatening sepsis by Bell and colleagues. Although not all infants progress through the various “Bell stages,” this classification scheme provides a useful format to describe the clinical picture associated with the development of NEC. In the earliest stage (Bell stage I), infants present with feeding intolerance. This is suggested by vomiting or by the presence of a large residual volume from a previous feeding in the stomach at the time of the next feed-ing. Following appropriate treatment, which consists of bowel rest and IV antibiotics, many of these infants will not progress to more advanced


Surgery_Schwartz

Surgery_Schwartz. feeding in the stomach at the time of the next feed-ing. Following appropriate treatment, which consists of bowel rest and IV antibiotics, many of these infants will not progress to more advanced stages of NEC. These infants are colloqui-ally described as suffering from an “NEC scare” and represent a population of neonates who are at risk of developing more severe NEC if a more prolonged period of stress supervenes.Infants with Bell stage II have established NEC that is not immediately life-threatening. Clinical findings include abdomi-nal distention and tenderness, bilious nasogastric aspirate, and bloody stools. These findings indicate the development of intestinal ileus and mucosal ischemia, respectively. Abdominal examination may reveal a palpable mass indicating the pres-ence of an inflamed loop of bowel, diffuse abdominal tender-ness, cellulitis, and edema of the anterior abdominal wall. The infant may appear systemically ill, with decreased urine output, hypotension,


Surgery_Schwartz

Surgery_Schwartz. of an inflamed loop of bowel, diffuse abdominal tender-ness, cellulitis, and edema of the anterior abdominal wall. The infant may appear systemically ill, with decreased urine output, hypotension, tachycardia, and noncardiac pulmonary edema. Hematologic evaluation reveals either leukocytosis or leukope-nia, an increase in the number of bands, and thrombocytopenia. An increase in the blood urea nitrogen and plasma creatinine level may be found, which signify the development of renal dys-function. The diagnosis of NEC may be confirmed by abdomi-nal radiography. The pathognomonic radiographic finding in NEC is pneumatosis intestinalis, which represents invasion of the ischemic mucosa by gas producing microbes (Fig. 39-19). Other findings include the presence of ileus or portal venous gas. The latter is a transient finding that indicates the presence of severe NEC with intestinal necrosis. A fixed loop of bowel may be seen on serial abdominal radiographs, which suggests the possibility


Surgery_Schwartz

Surgery_Schwartz. The latter is a transient finding that indicates the presence of severe NEC with intestinal necrosis. A fixed loop of bowel may be seen on serial abdominal radiographs, which suggests the possibility that a diseased loop of bowel, potentially with a localized perforation, is present. Although these infants are at risk of progressing to more severe disease, with timely and appropriate treatment, they often recover.Infants with Bell stage III have the most advanced form of NEC. Abdominal radiographs often demonstrate the presence of pneumoperitoneum, indicating that intestinal perforation has occurred. These patients may develop a fulminant course with progressive peritonitis, acidosis, sepsis, disseminated intravas-cular coagulopathy, and death.Pathogenesis of Necrotizing Enterocolitis. Several theories have been proposed to explain the development of NEC. In gen-eral terms, the development of diffuse pneumatosis intestinalis—which is associated with the development of stage II NEC—is


Surgery_Schwartz

Surgery_Schwartz. theories have been proposed to explain the development of NEC. In gen-eral terms, the development of diffuse pneumatosis intestinalis—which is associated with the development of stage II NEC—is thought to be due to the presence of gas within the wall of the intestine from enteric bacteria, suggesting the causative role of bacteria in the pathogenesis of NEC. Furthermore, the develop-ment of pneumoperitoneum indicates disease progression with severe disruption of the intestinal barrier (intestinal perforation). Finally, systemic sepsis with diffuse multisystem organ dysfunc-tion suggests the role for circulating proinflammatory cytokines in the pathogenesis of NEC. It has also been demonstrated that the premature intestine responds in an exaggerated fashion to bacterial products, rendering the host susceptible to barrier dys-function and the development of NEC. Various groups have shown that NEC pathogenesis requires activation of the bacterial receptor—Toll-like receptor 4 (TLR4)—in


Surgery_Schwartz

Surgery_Schwartz. the host susceptible to barrier dys-function and the development of NEC. Various groups have shown that NEC pathogenesis requires activation of the bacterial receptor—Toll-like receptor 4 (TLR4)—in the intestinal epithe-lium. The expression of TLR4 is significantly elevated in the premature infant intestine as compared with the full-term infant intestine, a consequence of the role that TLR4 plays in normal intestinal development. When the infant is born prematurely and TLR4 expression levels are elevated, subsequent activation of TLR4 by colonizing bacteria in the neonatal intensive care unit leads to the induction of a severe proinflammatory response and the development of NEC. It is noteworthy that breast milk—long known to be protective against NEC—is able to suppress TLR4 signaling and that synthetic TLR4 antagonists are known to prevent NEC in preclinical models, suggesting the possibility of preventive approaches for this disease.Treatment. In all infants suspected of having


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Surgery_Schwartz. and that synthetic TLR4 antagonists are known to prevent NEC in preclinical models, suggesting the possibility of preventive approaches for this disease.Treatment. In all infants suspected of having NEC, feedings are discontinued, a nasogastric tube is placed, and broad-spec-trum parenteral antibiotics are given. The infant is resuscitated, and inotropes are administered to maintain perfusion as needed. Intubation and mechanical ventilation may be required to main-tain oxygenation. Total parenteral nutrition is started. Subse-quent treatment may be influenced by the particular stage of NEC that is present. Patients with Bell stage I are closely moni-tored and generally remain NPO and on IV antibiotics for 7 to 10 days, prior to reinitiating enteral nutrition. If the infant fully recovers, feedings may be reinitiated.Patients with Bell stage II disease merit close observa-tion. Serial physical examinations are performed looking for the development of diffuse peritonitis, a fixed mass,


Surgery_Schwartz

Surgery_Schwartz. feedings may be reinitiated.Patients with Bell stage II disease merit close observa-tion. Serial physical examinations are performed looking for the development of diffuse peritonitis, a fixed mass, progres-sive abdominal wall cellulitis or systemic sepsis. If infants fail to improve after several days of treatment, consideration should be given to exploratory laparotomy. Paracentesis may be per-formed, and if the Gram stain demonstrates multiple organisms and leukocytes, perforation of the bowel should be suspected, and patients should undergo laparotomy.Brunicardi_Ch39_p1705-p1758.indd 172912/02/19 11:26 AM 1730SPECIFIC CONSIDERATIONSPART IIIn the most severe form of NEC (Bell stage III), patients have definite intestinal perforation or have not responded to nonoperative therapy. Two schools of thought direct fur-ther management. One group favors exploratory laparotomy. At laparotomy, frankly gangrenous or perforated bowel is resected, and the intestinal ends are brought out as


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Surgery_Schwartz. schools of thought direct fur-ther management. One group favors exploratory laparotomy. At laparotomy, frankly gangrenous or perforated bowel is resected, and the intestinal ends are brought out as stomas. When there is massive intestinal involvement, marginally viable bowel is retained and a “second-look” procedure is carried out after the infant stabilizes (24–48 hours). Patients with extensive necrosis at the second look may be managed by placing a proximal diverting stoma, resecting bowel that is definitely not viable, and leaving questionably viable bowel behind, distal to the diverted segment. When the intestine is viable except for a localized perforation without diffuse peri-tonitis and if the infant’s clinical condition permits, intestinal anastomosis may be performed. In cases where the diseased, perforated segment cannot be safely resected, drainage cath-eters may be left in the region of the diseased bowel, and the infant is allowed to stabilize.An alternative approach to


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Surgery_Schwartz. the diseased, perforated segment cannot be safely resected, drainage cath-eters may be left in the region of the diseased bowel, and the infant is allowed to stabilize.An alternative approach to the management of infants with perforated NEC involves drainage of the peritoneal cavity. This may be performed under local anesthesia at the bedside, and it can be an effective means of stabilizing the des-perately ill infant by relieving increased intra-abdominal pres-sure and allowing ventilation. When successful, this method also allows for drainage of perforated bowel by establishing a controlled fistula. Approximately one-third of infants treated with drainage alone survive without requiring additional oper-ations. Infants that do not respond to peritoneal drainage alone after 48 to 72 hours should undergo laparotomy. This proce-dure allows for the resection of frankly necrotic bowel diver-sion of the fecal stream and facilitates more effective drainage. It is noteworthy that a recent