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Surgery_Schwartz. 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 randomized controlled trial dem-onstrated that outcomes were similar in infants with NEC that were treated either with primary peritoneal drainage or lapa-rotomy, although this study was criticized for the large number of patients who were excluded from randomization. There was also concern that a number of patients who were thought to have NEC may actually have had spontaneous intestinal per-foration, given their lack of pneumatosis and relatively early onset of presentation; these patients would be anticipated to improve after peritoneal drainage due to the more local nature of their disease process.Necrotizing Enterocolitis in Older Infants. Although NEC is typically a disease that affects preterm infants, several inde-pendent groups have reported a tendency for early onset of NEC in term


Surgery_Schwartz

Surgery_Schwartz. Enterocolitis in Older Infants. Although NEC is typically a disease that affects preterm infants, several inde-pendent groups have reported a tendency for early onset of NEC in term and near-term infants. In these patients, the pattern of disease was found to be different from that found in premature infants. Specifically, NEC in older infants typically is localized to the end of the small intestine and beginning of the colon, sug-gestive of an ischemic pathophysiology. There are four pertinent associations that are observed in term infants that develop NEC: congenital heart disease, in utero growth restriction, polycythe-mia, and perinatal hypoxic-ischemic events. As with NEC in preterm infants, NEC in older patients is also associated with formula consumption and is very rare in exclusively breastfed infants. Patients with NEC at full term typically present with bloody stools and may be characterized by rapid onset of symp-toms and a fulminant course. Thus, although it is true that


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Surgery_Schwartz. breastfed infants. Patients with NEC at full term typically present with bloody stools and may be characterized by rapid onset of symp-toms and a fulminant course. Thus, although it is true that NEC is typically a disease of premature babies, in the appropriate setting, NEC can develop at any age.Spontaneous Intestinal Perforation Versus Necrotizing Enterocolitis. In addition to NEC, preterm infants with intes-tinal pathology may develop spontaneous intestinal perforation (SIP). SIP is a distinct clinical entity from NEC, and it is essen-tially a perforation in the terminal ileum. The histopathology of SIP is different from NEC. Specifically, the mucosa is intact and not necrotic, there is no sign of ischemia, and the submucosa is thinned at the site of perforation. In contrast to NEC, pneuma-tosis intestinalis is absent in SIP. Moreover, the demographics of NEC and SIP are slightly different, in that patients with SIP tend to be slightly more premature, smaller, and more likely to


Surgery_Schwartz

Surgery_Schwartz. pneuma-tosis intestinalis is absent in SIP. Moreover, the demographics of NEC and SIP are slightly different, in that patients with SIP tend to be slightly more premature, smaller, and more likely to have been on inotropic support. SIP occurs in two separate time points, both within a few days after birth and approximately 10 days later, and in all cases, free air will be present, but pneu-matosis will be absent. Because patients with SIP have isolated disease without necrosis or systemic inflammation, they tend to have a better outcome and are likely to respond better to peri-toneal drainage. In short, the diagnosis of SIP versus NEC has important prognostic significance. Treatment for SIP should pri-marily be surgical, with intestinal resection and stoma creation, followed by stoma reversal once the child is stable.In both SIP and NEC, the timing of stoma closure is a mat-ter of ongoing debate. Whereas in the past, pediatric surgeons typically waited until the child reached 5 kg or


Surgery_Schwartz

Surgery_Schwartz. once the child is stable.In both SIP and NEC, the timing of stoma closure is a mat-ter of ongoing debate. Whereas in the past, pediatric surgeons typically waited until the child reached 5 kg or so, experience indicates that there is no benefit in waiting this long, and chil-dren tolerate stoma closure very well when they are at much lower weights. One approach is to close the stoma when the cal-culated gestational age is approximately 38 to 40 weeks, which will, on average, be at approximately 6 weeks after the initial surgery. This time point is selected based on the observation that proinflammatory gene expression has normalized by then, and NEC recurrence is very unlikely.Outcome. Survival in patients with NEC is dependent on the stage of disease, the extent of prematurity, and the presence of associated comorbidities. Survival by stage has recently been shown to be approximately 85%, 65%, and 35% for stages I, II, and III, respectively. Strictures develop in 20% of medically or


Surgery_Schwartz

Surgery_Schwartz. of associated comorbidities. Survival by stage has recently been shown to be approximately 85%, 65%, and 35% for stages I, II, and III, respectively. Strictures develop in 20% of medically or surgically treated patients, and a contrast enema is mandatory before reestablishing intestinal continuity. If all other factors are favorable, the ileostomy is closed when the child is between 2 and 2.5 kg. At the time of stoma closure, the entire intestine should be examined to search for areas of NEC. Patients who develop massive intestinal necrosis are at risk of developing short bowel syndrome, particularly when the total length of the viable intes-tinal segment is less than 40 cm. These patients require TPN to provide adequate calories for growth and development, and may develop parenteral nutrition associated cholestasis and hepatic fibrosis. In a significant number of these patients, transplantation of the liver and small bowel may be required.Short Bowel SyndromeShort bowel syndrome


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Surgery_Schwartz. nutrition associated cholestasis and hepatic fibrosis. In a significant number of these patients, transplantation of the liver and small bowel may be required.Short Bowel SyndromeShort bowel syndrome (SBS) is an extremely morbid condition with an increasing incidence. Various congenital and perinatal acquired conditions such as gastroschisis, malrotation, atresia, and NEC may lead to SBS. Medical and surgical treatment options carry high dollar and human costs and morbidities including multiple infections and hospitalizations for vascular access, liver failure in conjunction with parenteral nutrition–associated cholestasis, and death. Medical centers that have developed multidisciplinary clinics focused on treating children with short bowel syndrome have achieved significant success in Brunicardi_Ch39_p1705-p1758.indd 173012/02/19 11:26 AM 1731PEDIATRIC SURGERYCHAPTER 39preventing line infections, reducing cholestasis, and improving nutrition and feeding independence


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Surgery_Schwartz. success in Brunicardi_Ch39_p1705-p1758.indd 173012/02/19 11:26 AM 1731PEDIATRIC SURGERYCHAPTER 39preventing line infections, reducing cholestasis, and improving nutrition and feeding independence overall.IntussusceptionIntussusception is the leading cause of intestinal obstruction in the young child. It refers to the condition whereby a segment of intestine becomes drawn into the lumen of the more proximal bowel. The process usually begins in the region of the termi-nal ileum, and extends distally into the ascending, transverse, or descending colon. Rarely, an intussusception may prolapse through the rectum.The cause of intussusception is not clear, although one hypothesis suggests that hypertrophy of the Peyer’s patches in the terminal ileum from an antecedent viral infection acts as a lead point. Peristaltic action of the intestine then causes the bowel distal to the lead point to invaginate into itself. Idio-pathic intussusception occurs in children between the ages of


Surgery_Schwartz

Surgery_Schwartz. acts as a lead point. Peristaltic action of the intestine then causes the bowel distal to the lead point to invaginate into itself. Idio-pathic intussusception occurs in children between the ages of approximately 6 and 24 months of age. Beyond this age group, one should consider the possibility that a pathologic lead point maybe present. These include polyps, malignant tumors such as lymphoma, enteric duplication cysts or Meckel’s diverticu-lum. Such intussusceptions are rarely reduced by air or con-trast enema, and thus the lead point is identified when operative reduction of the intussusception is performed.Clinical Manifestations. Since intussusception is frequently preceded by a gastrointestinal viral illness, the onset may not be easily determined. Typically, the infant develops paroxysms of crampy abdominal pain and intermittent vomiting. Between attacks, the infant may act normally, but as symptoms progress, increasing lethargy develops. Bloody mucus (“currant-jelly” stool) may


Surgery_Schwartz

Surgery_Schwartz. of crampy abdominal pain and intermittent vomiting. Between attacks, the infant may act normally, but as symptoms progress, increasing lethargy develops. Bloody mucus (“currant-jelly” stool) may be passed per rectum. Ultimately, if reduction is not accomplished, gangrene of the intussusceptum occurs, and perforation may ensue. On physical examination, an elongated mass is detected in the right upper quadrant or epigastrium with an absence of bowel in the right lower quadrant (Dance’s sign). The mass may be seen on plain abdominal X-ray but is more easily demonstrated on air or contrast enema.Treatment. Patients with intussusception should be assessed for the presence of peritonitis and for the severity of systemic illness. Following resuscitation and administration of IV antibi-otics, the child is assessed for suitability to proceed with radio-graphic versus surgical reduction. In the absence of peritonitis, the child should undergo radiographic reduction. If peritonitis is present,


Surgery_Schwartz

Surgery_Schwartz. child is assessed for suitability to proceed with radio-graphic versus surgical reduction. In the absence of peritonitis, the child should undergo radiographic reduction. If peritonitis is present, or if the child appears systemically ill, urgent lapa-rotomy is indicated.In the stable patient, the air enema is both diagnostic and may be curative, and it is the preferred method of diagnosis and treatment of intussusception. Air is introduced with a manom-eter, and the pressure that is administered is carefully monitored. Under most instances, this should not exceed 120 mmHg. Suc-cessful reduction is marked by free reflux of air into multiple loops of small bowel and symptomatic improvement as the infant suddenly becomes pain free. Unless both of these signs are observed, it cannot be assumed that the intussusception is reduced. If reduction is unsuccessful, and the infant remains stable, the infant should be brought back to the radiology suite for a repeat attempt at reduction after a


Surgery_Schwartz

Surgery_Schwartz. that the intussusception is reduced. If reduction is unsuccessful, and the infant remains stable, the infant should be brought back to the radiology suite for a repeat attempt at reduction after a few hours. This strategy has improved the success rate of nonoperative reduction in many centers. In addition, hydrostatic reduction with barium may be useful if pneumatic reduction is unsuccessful. The overall suc-cess rate of radiographic reduction varies based on the experi-ence of the center, and it is typically between 60% and 90%.If nonoperative reduction is successful, the infant may be given oral fluids after a period of observation. Failure to reduce the intussusception mandates surgery. which can be approached through an open or laparoscopic technique. In an open procedure, exploration is carried out through a right lower quadrant incision, delivering the intussuscepted mass into the wound. Reduction usually can be accomplished by gentle distal pressure, where the intussusceptum is


Surgery_Schwartz

Surgery_Schwartz. is carried out through a right lower quadrant incision, delivering the intussuscepted mass into the wound. Reduction usually can be accomplished by gentle distal pressure, where the intussusceptum is gently milked out of the intussuscipiens (Fig. 39-20). Care should be taken not to pull the bowel out, as this can cause damage to the bowel wall. The blood supply to the appendix is often compromised, and appen-dectomy is therefore often performed. If the bowel is frankly gangrenous, resection and primary anastomosis is performed. In experienced hands, laparoscopic reduction may be performed, even in very young infants. This is performed using a 5-mm lap-aroscope placed in the umbilicus, and two additional 5 mm ports in the left and right lower quadrants. The bowel is inspected, and if it appears to be viable, reduction is performed by milking the bowel or using gentle traction, although this approach is nor-mally discouraged during manual reduction. Atraumatic bowel graspers allow the


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Surgery_Schwartz. to be viable, reduction is performed by milking the bowel or using gentle traction, although this approach is nor-mally discouraged during manual reduction. Atraumatic bowel graspers allow the bowel to be handled without injuring it.IV fluids are continued until the postoperative ileus sub-sides. Patients are started on clear liquids, and their diet is advanced as tolerated. Of note, recurrent intussusception occurs in 5% to 10% of patients, independent of whether the bowel is reduced radiographically or surgically. Patients present with recurrent symptoms in the immediate postoperative period. Treatment involves repeat air enema, which is successful in most cases. In patients who experience three or more episodes of intussusception, the presence of a pathologic lead point should be suspected and carefully evaluated using contrast stud-ies. After the third episode of intussusception, many pediatric surgeons will perform an exploratory laparotomy to reduce the bowel and to resect a


Surgery_Schwartz

Surgery_Schwartz. and carefully evaluated using contrast stud-ies. After the third episode of intussusception, many pediatric surgeons will perform an exploratory laparotomy to reduce the bowel and to resect a pathologic lead point if identified.AppendicitisPresentation. Correct diagnosis of appendicitis in children can be one of the most humbling and challenging tasks facing the pediatric surgeon. The classical presentation is known to all students and practitioners of surgery: generalized abdomi-nal pain that localizes to the right lower quadrant followed by nausea, vomiting, fever, and localized peritoneal irritation in the region of McBurney’s point. When children present in this Figure 39-20. Open reduction of intussusception showing how the bowel is milked backwards to relieve the obstruction.Brunicardi_Ch39_p1705-p1758.indd 173112/02/19 11:26 AM 1732SPECIFIC CONSIDERATIONSPART IImanner, there should be little diagnostic delay. The child should be made NPO, administered IV fluids and


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Surgery_Schwartz. 173112/02/19 11:26 AM 1732SPECIFIC CONSIDERATIONSPART IImanner, there should be little diagnostic delay. The child should be made NPO, administered IV fluids and broad-spectrum anti-biotics, and brought to the operating room for an appendec-tomy. However, children often do not present in this manner. The coexistence of nonspecific viral syndromes and the inability of young children to describe the location and quality of their pain often result in diagnostic delay. As a result, children with appendicitis often present with perforation, particularly those who are under 5 years of age. Perforation increases the length of hospital stay and makes the overall course of the illness sig-nificantly more complex.Diagnosis of Appendicitis in Children. There have been significant improvements in the role of radiographic studies in the diagnosis of acute appendicitis. While CT is quite reliable in making the diagnosis, US is very useful when performed in experienced centers and good


Surgery_Schwartz

Surgery_Schwartz. in the role of radiographic studies in the diagnosis of acute appendicitis. While CT is quite reliable in making the diagnosis, US is very useful when performed in experienced centers and good visualization of the appendix is achieved. MRI may be performed where available with high specificity and sensitivity—and avoidance of radiation. US is very useful for excluding ovarian causes of abdominal pain. Despite these radiographic measures, the diagnosis of appendi-citis remains largely clinical, and each clinician should develop his or her own threshold to operate or to observe the patient. A reasonable practice guideline is as follows. When the diagno-sis is clinically apparent, appendectomy should obviously be performed with minimal delay. Localized right lower quadrant tenderness associated with low-grade fever and leukocytosis in boys should prompt surgical exploration. In girls, ovarian or uterine pathology must also be considered. When there is diag-nostic uncertainty, the child


Surgery_Schwartz

Surgery_Schwartz. with low-grade fever and leukocytosis in boys should prompt surgical exploration. In girls, ovarian or uterine pathology must also be considered. When there is diag-nostic uncertainty, the child may be observed, rehydrated, and reassessed. In girls of menstruating age, an US may be obtained to exclude ovarian pathology (cysts, torsion, or tumor). If all studies are negative, yet the pain persists, and the abdominal findings remain equivocal, diagnostic laparoscopy may be employed to determine the etiology of the abdominal pain. The appendix should be removed even if it appears to be normal, unless another pathologic cause of the abdominal pain is defini-tively identified and the appendectomy would substantially increase morbidity.Surgical Treatment of Appendicitis. The definitive treat-ment for acute appendicitis is appendectomy. Prior to surgery, it is important that patients receive adequate IV fluids in order to correct dehydration that commonly develops as a result of fever and


Surgery_Schwartz

Surgery_Schwartz. for acute appendicitis is appendectomy. Prior to surgery, it is important that patients receive adequate IV fluids in order to correct dehydration that commonly develops as a result of fever and vomiting in patients with appendicitis. Patients should also be started on antibiotics (such as a second-generation cepha-losporin). Most surgeons will perform a laparoscopic appen-dectomy, which may have some advantage over removing the appendix through a single, larger incision. During the laparo-scopic appendectomy, a small incision is made at the umbilicus, and two additional incisions are made in the lower abdomen. The appendix is typically delivered through the umbilicus, and all incisions are then closed, with dissolvable sutures. If the appendix is not ruptured, the patient may start drinking liq-uids shortly after waking up from the operation, and may be advanced to a solid diet the next day. In general, the same steps are taken when appendectomy is performed through an open approach.


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Surgery_Schwartz. liq-uids shortly after waking up from the operation, and may be advanced to a solid diet the next day. In general, the same steps are taken when appendectomy is performed through an open approach. The most common complication after appendectomy is a surgical site infection. Other risks—including bleeding or damage to other structures inside the abdomen—are extremely rare. Recovery from surgery is dependent upon the individual patient. Most children are back to school approximately 1 week from surgery and usually are allowed to return to full physical Figure 39-21. Computed tomography scan of the abdomen showing the presence of a ruptured appendix with pelvic fluid and a fecalith (arrow).activity after 2 to 3 weeks. During the recovery period, over-the-counter pain medication may be required. Older patients tend to require a longer time for full recovery.Management of the Child With Perforated Appendicitis. The signs and symptoms of perforated appendicitis can closely mimic those of


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Surgery_Schwartz. Older patients tend to require a longer time for full recovery.Management of the Child With Perforated Appendicitis. The signs and symptoms of perforated appendicitis can closely mimic those of gastroenteritis and include abdominal pain, vom-iting, and diarrhea. Alternatively, the child may present with symptoms of intestinal obstruction. An abdominal mass may be present in the lower abdomen. When the symptoms have been present for more than 4 or 5 days, and an abscess is suspected, it is reasonable to obtain a computerized tomogram of the abdo-men and pelvis with IV, oral, and rectal contrast in order to visu-alize the appendix and the presence of an associated abscess, phlegmon, or fecalith (Fig. 39-21).An individualized approach is necessary for the child who presents with perforated appendicitis. When there is evidence of generalized peritonitis, intestinal obstruction or evidence of systemic toxicity, the child should undergo appendectomy. This should be delayed only for as long


Surgery_Schwartz

Surgery_Schwartz. When there is evidence of generalized peritonitis, intestinal obstruction or evidence of systemic toxicity, the child should undergo appendectomy. This should be delayed only for as long as is required to ensure ade-quate fluid resuscitation and administration of broad-spectrum antibiotics. The operation can be performed through an open or through a laparoscopic approach. One distinct advantage of the laparoscopic approach is that it provides excellent visualiza-tion of the pelvis and all four quadrants of the abdomen. At the time of surgery, adhesions are gently lysed, abscess cavities are drained and the appendix is removed. Drains are seldom used, and the skin incisions can be closed primarily. If a fecalith is identified outside the appendix on computerized tomography, every effort should be made to retrieve it and to remove it along with the appendix, if at all possible. Often, the child in whom symptoms have been present for more than 4 or 5 days will pres-ent with an abscess


Surgery_Schwartz

Surgery_Schwartz. should be made to retrieve it and to remove it along with the appendix, if at all possible. Often, the child in whom symptoms have been present for more than 4 or 5 days will pres-ent with an abscess without evidence of generalized peritonitis. Under these circumstances, it is appropriate to perform image-guided percutaneous drainage of the abscess followed by broad-spectrum antibiotic therapy. The inflammation will generally subside within several days, and the appendix can be safely removed as an outpatient 6 to 8 weeks later. If the child’s symp-toms do not improve, or if the abscess is not amenable to per-cutaneous drainage, then laparoscopic or open appendectomy and abscess drainage is required. Patients who present with a phlegmon in the region of a perforated appendix may be man-aged in a similar manner. In general, children who are younger Brunicardi_Ch39_p1705-p1758.indd 173212/02/19 11:26 AM 1733PEDIATRIC SURGERYCHAPTER 39than 4 or 5 years of age do not respond as well


Surgery_Schwartz

Surgery_Schwartz. in a similar manner. In general, children who are younger Brunicardi_Ch39_p1705-p1758.indd 173212/02/19 11:26 AM 1733PEDIATRIC SURGERYCHAPTER 39than 4 or 5 years of age do not respond as well to an initial nonoperative approach because their bodies do not localize or isolate the inflammatory process. Thus, these patients are more likely to require early surgical intervention. Patients who have had symptoms of appendicitis for no more than 4 days should probably undergo “early” appendectomy because the inflamma-tory response is not as excessive during that initial period and the procedure can be performed safely.Nonoperative Management of Acute Appendicitis. Despite the fact that surgical removal of the acutely inflammation appendix is effective in all cases, there has been a growing rec-ognition that certain children will respond to antibiotics alone and thus avoid surgery. Several trials have shown that acute appendicitis may be treated with antibiotics alone effectively in


Surgery_Schwartz

Surgery_Schwartz. rec-ognition that certain children will respond to antibiotics alone and thus avoid surgery. Several trials have shown that acute appendicitis may be treated with antibiotics alone effectively in nearly 80% of patients. However, the failure rate is considered unacceptably high for many patients, who effectively will have suffered a delay from definitive care. Furthermore, the hetero-geneity of disease presentation, and varying degree of illness severity, make it quite difficult to predict who will respond to antibiotics alone. This question is currently being answered in the United States in the form of a randomized controlled trial that is recruiting over 1500 patients in eight states, which will be divided into antibiotic therapy versus surgery (ClinicalTrials.gov, identifier NCT02800785).Other Causes of Abdominal Pain That Mimic Appendi-citis in Children. As mentioned earlier, appendicitis can be one of the most difficult diagnoses to establish in children with abdominal pain, in


Surgery_Schwartz

Surgery_Schwartz. Causes of Abdominal Pain That Mimic Appendi-citis in Children. As mentioned earlier, appendicitis can be one of the most difficult diagnoses to establish in children with abdominal pain, in part because of the large number of diseases that present in a similar fashion. Patients with urinary tract infection can present very similarly to those with appen-dicitis. However, patients with urinary tract infection are less likely to present with vomiting and are likely to also experience difficulty with urination, characterized by pressure, burning, and frequency. Constipation may be commonly confused with appendicitis in its earliest stages. However, patients with consti-pation rarely have fever and will not have abnormalities in their blood work. Ovarian torsion can mimic appendicitis, given the severe abdominal pain that accompanies this condition. How-ever, patients with ovarian torsion are generally asymptomatic until the acute onset of severe pain. By contrast, patients with


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Surgery_Schwartz. given the severe abdominal pain that accompanies this condition. How-ever, patients with ovarian torsion are generally asymptomatic until the acute onset of severe pain. By contrast, patients with appendicitis generally experience gradual onset of pain asso-ciated with nausea and vomiting. Finally, children and young adults are always at risk for the development of gastroenteritis. However, unlike appendicitis, patients with gastroenteritis gen-erally present with persistent vomiting and occasionally diar-rhea, which precedes the onset of the abdominal pain.Intestinal DuplicationsDuplications represent mucosa-lined structures that are in con-tinuity with the gastrointestinal tract. Although they can occur at any level in the gastrointestinal tract, duplications are found most commonly in the ileum within the leaves of the mesen-tery. Duplications may be long and tubular but usually are cystic masses. In all cases, they share a common wall with the intes-tine. Symptoms associated with


Surgery_Schwartz

Surgery_Schwartz. the ileum within the leaves of the mesen-tery. Duplications may be long and tubular but usually are cystic masses. In all cases, they share a common wall with the intes-tine. Symptoms associated with enteric duplication cysts include recurrent abdominal pain, emesis from intestinal obstruction, or hematochezia. Such bleeding typically results from ulceration in the duplication or in the adjacent intestine if the duplication contains ectopic gastric mucosa. On examination, a palpable mass is often identified. Children may also develop intestinal obstruction. Torsion may produce gangrene and perforation.The ability to make a preoperative diagnosis of enteric duplication cyst usually depends on the presentation. CT, US, and technetium pertechnetate scanning can be very helpful. Occasionally, a duplication can be seen on small bowel follow-through or barium enema. In the case of short duplications, resection of the cyst and adjacent intestine with end-to-end anastomosis can be performed.


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Surgery_Schwartz. a duplication can be seen on small bowel follow-through or barium enema. In the case of short duplications, resection of the cyst and adjacent intestine with end-to-end anastomosis can be performed. If resection of long duplications would compromise intestinal length, multiple enterotomies and mucosal stripping in the duplicated segment will allow the walls to collapse and become adherent. An alternative method is to divide the common wall using the GIA stapler, forming a com-mon lumen. Patients with duplications who undergo complete excision without compromise of the length of remaining intes-tine have an excellent prognosis.Meckel’s DiverticulumA Meckel’s diverticulum is a remnant of a portion of the embryonic omphalomesenteric (vitelline) duct. It is located on the antimesenteric border of the ileum, usually within 2 ft of the ileocecal valve (Fig. 39-22). It may be found incidentally at surgery or may present with inflammation masquerading as appendicitis. Perforation of a


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Surgery_Schwartz. border of the ileum, usually within 2 ft of the ileocecal valve (Fig. 39-22). It may be found incidentally at surgery or may present with inflammation masquerading as appendicitis. Perforation of a Meckel’s diverticulum may occur if the outpouching becomes impacted with food, leading to dis-tention and necrosis. Occasionally, bands of tissue extend from the Meckel’s diverticulum to the anterior abdominal wall, and these may represent lead points around which internal hernias may develop. This is an important cause of intestinal obstruction in the older child who has a scarless abdomen. Similar to dupli-cations, ectopic gastric mucosa may produce ileal ulcerations that bleed and lead to the passage of maroon-colored stools. Pancreatic mucosa may also be present. Diagnosis may be made by technetium pertechnetate scans when the patient presents with bleeding. Treatment is surgical. If the base is narrow and there is no mass present in the lumen of the diverticulum, a wedge resection of


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Surgery_Schwartz. pertechnetate scans when the patient presents with bleeding. Treatment is surgical. If the base is narrow and there is no mass present in the lumen of the diverticulum, a wedge resection of the diverticulum with transverse closure of the ileum can be performed. A linear stapler is especially useful in this circumstance. When a mass of ectopic tissue is palpable, if the base is wide, or when there is inflammation, it is prefer-able to perform a resection of the involved bowel and end-to-end ileoileostomy.Mesenteric CystsMesenteric cysts are similar to duplications in their location within the mesentery. However, they do not contain any mucosa or muscular wall. Chylous cysts may result from congenital Figure 39-22. Operative photograph showing the presence of a Meckel’s diverticulum (arrow).Brunicardi_Ch39_p1705-p1758.indd 173312/02/19 11:26 AM 1734SPECIFIC CONSIDERATIONSPART IIlymphatic obstruction. Mesenteric cysts can cause intestinal obstruction or may present as an abdominal


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Surgery_Schwartz. 173312/02/19 11:26 AM 1734SPECIFIC CONSIDERATIONSPART IIlymphatic obstruction. Mesenteric cysts can cause intestinal obstruction or may present as an abdominal mass. The diagno-sis may be made by abdominal US or CT. Treatment involves surgical excision. This may require resection of the adjacent intestine, particularly for extensive, multicystic lesions. In cases where complete excision is not possible due to the close proxim-ity to vital structures, partial excision or marsupialization should be performed.Hirschsprung’s DiseasePathogenesis. In his classic textbook entitled Pediatric Sur-gery, Dr. Orvar Swenson, who is eponymously associated with one of the classic surgical treatments for Hirschsprung’s dis-ease, described this condition as follows: “Congenital megaco-lon is caused by a malformation in the pelvic parasympathetic system which results in the absence of ganglion cells in Auer-bach’s plexus of a segment of distal colon. Not only is there an absence of ganglion cells,


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Surgery_Schwartz. a malformation in the pelvic parasympathetic system which results in the absence of ganglion cells in Auer-bach’s plexus of a segment of distal colon. Not only is there an absence of ganglion cells, but the nerve fibers are large and excessive in number, indicating that the anomaly may be more extensive than the absence of ganglion cells.” This narrative of Hirschsprung’s disease is as accurate today as it was more than 50 years ago and summarizes the essential pathologic fea-tures of this disease: absence of ganglion cells in Auerbach’s plexus and hypertrophy of associated nerve trunks. The cause of Hirschsprung’s disease remains incompletely understood, although current thinking suggests that the disease results from a defect in the migration of neural crest cells, which are the embryonic precursors of the intestinal ganglion cell. Under normal conditions, the neural crest cells migrate into the intes-tine from cephalad to caudad. The process is completed by the 12th week of


Surgery_Schwartz

Surgery_Schwartz. precursors of the intestinal ganglion cell. Under normal conditions, the neural crest cells migrate into the intes-tine from cephalad to caudad. The process is completed by the 12th week of gestation, but the migration from midtransverse colon to anus takes 4 weeks. During this latter period, the fetus is most vulnerable to defects in migration of neural crest cells. This may explain why most cases of aganglionosis involve the rectum and rectosigmoid. The length of the aganglionic segment of bowel is therefore determined by the most distal region that the migrating neural crest cells reach. In rare instances, total colonic aganglionosis may occur.Recent studies have shed light on the molecular basis for Hirschsprung’s disease. Patients with Hirschsprung’s disease have an increased frequency of mutations in several genes, including GDNF, its receptor Ret, or its coreceptor Gfra-1. Moreover, mutations in these genes also lead to aganglionic megacolon in mice, which provides the


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Surgery_Schwartz. frequency of mutations in several genes, including GDNF, its receptor Ret, or its coreceptor Gfra-1. Moreover, mutations in these genes also lead to aganglionic megacolon in mice, which provides the opportunity to study the function of the encoded proteins. Initial investigations indicate that GDNF promotes the survival, proliferation, and migration of mixed populations of neural crest cells in culture. Other studies have revealed that GDNF is expressed in the gut in advance of migrating neural crest cells and is chemoattrac-tive for neural crest cells in culture. These findings raise the possibility that mutations in the GDNF or Ret genes could lead to impaired neural crest migration in utero and the development of Hirschsprung’s disease.Clinical Presentation. The incidence of sporadic Hirschsprung’s disease is 1 in 5000 live births. There are reports of increased frequency of Hirschsprung’s disease in multiple generations of the same family. Occasionally, such families have


Surgery_Schwartz

Surgery_Schwartz. Hirschsprung’s disease is 1 in 5000 live births. There are reports of increased frequency of Hirschsprung’s disease in multiple generations of the same family. Occasionally, such families have mutations in the genes described earlier, includ-ing the Ret gene. Because the aganglionic colon does not permit normal peristalsis to occur, the presentation of children with Hirschsprung’s disease is characterized by a functional distal intestinal obstruction. In the newborn period, the most common symptoms are abdominal distention, failure to pass meconium, and bilious emesis. Any infant who does not pass meconium beyond 48 hours of life must be investigated for the presence of Hirschsprung’s disease. Occasionally, infants present with a dra-matic complication of Hirschsprung’s disease called enteroco-litis. This pattern of presentation is characterized by abdominal distention and tenderness, and it is associated with manifesta-tions of systemic toxicity that include fever, failure to thrive,


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Surgery_Schwartz. This pattern of presentation is characterized by abdominal distention and tenderness, and it is associated with manifesta-tions of systemic toxicity that include fever, failure to thrive, and lethargy. Infants are often dehydrated and demonstrate a leukocytosis or increase in circulating band forms on hemato-logic evaluation. On rectal examination, forceful expulsion of foul-smelling liquid feces is typically observed and represents the accumulation of stool under pressure in an obstructed dis-tal colon. Treatment includes rehydration, systemic antibiotics, nasogastric decompression, and rectal irrigations while the diag-nosis of Hirschsprung’s disease is being confirmed. In children that do not respond to nonoperative management, a decompres-sive stoma is required. It is important to ensure that this stoma is placed in ganglion-containing bowel, which must be confirmed by frozen section at the time of stoma creation.In approximately 20% of cases, the diagnosis of Hirschsprung’s


Surgery_Schwartz

Surgery_Schwartz. ensure that this stoma is placed in ganglion-containing bowel, which must be confirmed by frozen section at the time of stoma creation.In approximately 20% of cases, the diagnosis of Hirschsprung’s disease is made beyond the newborn period. These children have severe constipation, which has usually been treated with laxatives and enemas. Abdominal distention and failure to thrive may also be present at diagnosis.Diagnosis. The definitive diagnosis of Hirschsprung’s disease is made by rectal biopsy. Samples of mucosa and submucosa are obtained at 1 cm, 2 cm, and 3 cm from the dentate line. This can be performed at the bedside in the neonatal period without anes-thesia, as samples are taken in bowel that does not have somatic innervation and is thus not painful to the child. In older children, the procedure should be performed using IV sedation. The histo-pathology of Hirschsprung’s disease is the absence of ganglion cells in the myenteric plexuses, increased acetylcholinesterase


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Surgery_Schwartz. children, the procedure should be performed using IV sedation. The histo-pathology of Hirschsprung’s disease is the absence of ganglion cells in the myenteric plexuses, increased acetylcholinesterase staining, and the presence of hypertrophied nerve bundles.It is important to obtain a barium enema in children in whom the diagnosis of Hirschsprung’s disease is suspected. This test may demonstrate the location of the transition zone between the dilated ganglionic colon and the distal constricted aganglionic rectal segment. Our practice is to obtain this test before instituting rectal irrigations if possible so that the differ-ence in size between the proximal and distal bowel is preserved. Although the barium enema can only suggest, but not reliably establish, the diagnosis of Hirschsprung’s disease, it is very useful in excluding other causes of distal intestinal obstruction. These include small left colon syndrome (as occurs in infants of diabetic mothers), colonic atresia, meconium


Surgery_Schwartz

Surgery_Schwartz. disease, it is very useful in excluding other causes of distal intestinal obstruction. These include small left colon syndrome (as occurs in infants of diabetic mothers), colonic atresia, meconium plug syndrome, or the unused colon observed in infants after the administration of magnesium or tocolytic agents. The barium enema in total colonic aganglionosis may show a markedly shortened colon. Some surgeons have found the use of rectal manometry helpful, particularly in older children, although it is relatively inaccurate.Treatment. The diagnosis of Hirschsprung’s disease requires surgery in all cases. The classic surgical approach consisted of a multiple stage procedure. This included a colostomy in the newborn period, followed by a definitive pull-through operation after the child was over 10 kg. There are three viable options for the definitive pull through procedure that are currently used. Although individual surgeons may advocate one procedure over another, studies have


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Surgery_Schwartz. was over 10 kg. There are three viable options for the definitive pull through procedure that are currently used. Although individual surgeons may advocate one procedure over another, studies have demonstrated that the outcome after each type of operation is similar. For each of 6Brunicardi_Ch39_p1705-p1758.indd 173412/02/19 11:26 AM 1735PEDIATRIC SURGERYCHAPTER 39the operations that is performed, the principles of treatment include confirming the location in the bowel where the transition zone between ganglionic and aganglionic bowel exists, resecting the aganglionic segment of bowel, and performing an anastomosis of ganglionated bowel to either the anus or a cuff of rectal mucosa (Fig. 39-23).It is now well established that a primary pull-through pro-cedure can be performed safely, even in the newborn period. This approach follows the same treatment principles as a staged procedure and saves the patient from an additional surgical Figure 39-23. The three operations for surgical


Surgery_Schwartz

Surgery_Schwartz. even in the newborn period. This approach follows the same treatment principles as a staged procedure and saves the patient from an additional surgical Figure 39-23. The three operations for surgical correction of Hirschsprung’s disease. A. The Duhamel procedure leaves the rec-tum in place and brings ganglionic bowel into the retrorectal space. B. The Swenson procedure is a resection with end-to-end anastomo-sis performed by exteriorizing bowel ends through the anus. C. The Soave operation is performed by endorectal dissection and removal of mucosa from the aganglionic distal segment and bringing the ganglionic bowel down to the anus within the seromuscular tunnel.procedure. Many surgeons perform the intra-abdominal dissec-tion using the laparoscope. This approach is especially useful in the newborn period as this provides excellent visualization of the pelvis. In children with significant colonic distention, it is important to allow for a period of decompression using a rectal tube


Surgery_Schwartz

Surgery_Schwartz. the newborn period as this provides excellent visualization of the pelvis. In children with significant colonic distention, it is important to allow for a period of decompression using a rectal tube if a single-staged pull-through is to be performed. In older children with very distended, hypertrophied colon, it may be prudent to perform a colostomy to allow the bowel to decom-press prior to performing a pull-through procedure. However, it should be emphasized that there is no upper age limit for per-forming a primary pull-through.Of the three pull-through procedures performed for Hirschsprung’s disease, the first is the original Swenson pro-cedure. In this operation, the aganglionic rectum is dissected in the pelvis and removed down to the anus. The ganglionic colon is then anastomosed to the anus via a perineal approach. In the Duhamel procedure, dissection outside the rectum is confined to the retrorectal space, and the ganglionic colon is anastomosed posteriorly just above the


Surgery_Schwartz

Surgery_Schwartz. to the anus via a perineal approach. In the Duhamel procedure, dissection outside the rectum is confined to the retrorectal space, and the ganglionic colon is anastomosed posteriorly just above the anus. The anterior wall of the gangli-onic colon and the posterior wall of the aganglionic rectum are anastomosed, using a stapler. Although both of these procedures are extremely effective, they are limited by the possibility of damage to the parasympathetic nerves that are adjacent to the rectum. To circumvent this potential problem, Soave’s proce-dure involves dissection entirely within the rectum. The rectal mucosa is stripped from the muscular sleeve, and the gangli-onic colon is brought through this sleeve and anastomosed to the anus. This operation may be performed completely from below. In all cases, it is critical that the level at which ganglion-ated bowel exists be determined. Most surgeons believe that the anastomosis should be performed at least 5 cm from the point at which


Surgery_Schwartz

Surgery_Schwartz. In all cases, it is critical that the level at which ganglion-ated bowel exists be determined. Most surgeons believe that the anastomosis should be performed at least 5 cm from the point at which ganglion cells are found. This avoids performing a pull-through in the transition zone, which is associated with a high incidence of complications due to inadequate emptying of the pull-through segment. Up to one-third of patients who undergo a transition zone pull through will require a reoperation.The main complications of all procedures include post-operative enterocolitis, constipation, and anastomotic stricture. There is also a reported incidence of recurrent Hirschsprung’s disease, which may reflect either residual aganglionic bowel left behind after the pull-through, or the presence of ischemia in the pulled-through segment leading to ganglion cell loss. Long-term results with the three procedures are comparable and generally excellent in experienced hands. These three procedures also


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Surgery_Schwartz. in the pulled-through segment leading to ganglion cell loss. Long-term results with the three procedures are comparable and generally excellent in experienced hands. These three procedures also can be adapted for total colonic aganglionosis in which the ileum is used for the pull-through segment.Anorectal MalformationsAnatomic Description. Anorectal malformations describe a spectrum of congenital anomalies that include imperforate anus and persistent cloaca. Anorectal malformations occur in approximately 1 in 5000 live births and affect males and females almost equally. The embryologic basis includes failure of descent of the urorectal septum. The level to which this septum descends determines the type of anomaly that is present, which subsequently influences the surgical approach.In patients with imperforate anus, the rectum fails to descend through the external sphincter complex. Instead, the rectal pouch ends “blindly” in the pelvis, above or below the levator ani muscle. In most


Surgery_Schwartz

Surgery_Schwartz. with imperforate anus, the rectum fails to descend through the external sphincter complex. Instead, the rectal pouch ends “blindly” in the pelvis, above or below the levator ani muscle. In most cases, the blind rectal pouch com-municates more distally with the genitourinary system or with the perineum through a fistulous tract. Traditionally, anatomic Brunicardi_Ch39_p1705-p1758.indd 173512/02/19 11:26 AM 1736SPECIFIC CONSIDERATIONSPART IIFigure 39-24. Low imperforate anus in a male. Note the well-developed buttocks. The perineal fistula was found at the midline raphe.Figure 39-25. Imperforate anus in a female. A catheter has been placed into the fistula, which is in the vestibule of the vagina.description of imperforate anus has been characterized as either “high” or “low” depending on whether the rectum ends above the levator ani muscle complex or partially descends through this muscle (Fig. 39-24). Based upon this classification system, in male patients with high imperforate


Surgery_Schwartz

Surgery_Schwartz. on whether the rectum ends above the levator ani muscle complex or partially descends through this muscle (Fig. 39-24). Based upon this classification system, in male patients with high imperforate anus the rectum usually ends as a fistula into the membranous urethra. In females, high imperforate anus often occurs in the context of a persistent clo-aca. In both males and females, low lesions are associated with a fistula to the perineum. In males, the fistula connects with the median raphe of the scrotum or penis. In females, the fistula may end within the vestibule of the vagina, which is located immediately outside the hymen or at the perineum.Because this classification system is somewhat arbitrary, Peña proposed a classification system that specifically and unambiguously describes the location of the fistulous opening. In men, the fistula may communicate with: (a) the perineum (cutaneous perineal fistula); (b) the lowest portion of the poste-rior urethra (rectourethral bulbar


Surgery_Schwartz

Surgery_Schwartz. the location of the fistulous opening. In men, the fistula may communicate with: (a) the perineum (cutaneous perineal fistula); (b) the lowest portion of the poste-rior urethra (rectourethral bulbar fistula); (c) the upper portion of the posterior urethra (rectourethral prostatic fistula); or (d) the bladder neck (rectovesicular fistula). In females, the ure-thra may open to the perineum between the female genitalia and the center of the sphincter (cutaneous perineal fistula) or into the vestibule of the vagina (vestibular fistula) (Fig. 39-25). In both sexes, the rectum may end in a completely blind fashion (imperforate anus without fistula). In rare cases, patients may have a normal anal canal, yet there may be total atresia or severe stenosis of the rectum.The most frequent defect in males is imperforate anus with rectourethral fistula, followed by rectoperineal fistula, then rectovesical fistula or rectobladder neck. In females, the most frequent defect is the rectovestibular


Surgery_Schwartz

Surgery_Schwartz. in males is imperforate anus with rectourethral fistula, followed by rectoperineal fistula, then rectovesical fistula or rectobladder neck. In females, the most frequent defect is the rectovestibular defect, followed by the cutaneous perineal fistula. The third most common defect in females is the persistent cloaca. This lesion represents a wide spectrum of malformations in which the rectum, vagina, and urinary tract meet and fuse into a single common channel. On physical examination, a single perineal orifice is observed, and it is located at the place where the urethra normally opens. Typi-cally, the external genitalia are hypoplastic.Associated Malformations. Approximately 60% of patients have an associated malformation. The most common is a urinary tract defect, which occurs in approximately 50% of patients. Skeletal defects are also seen, and the sacrum is most commonly involved. Spinal cord anomalies especially tethered cored are common, particularly in children with high


Surgery_Schwartz

Surgery_Schwartz. approximately 50% of patients. Skeletal defects are also seen, and the sacrum is most commonly involved. Spinal cord anomalies especially tethered cored are common, particularly in children with high lesions. Gastroin-testinal anomalies occur, most commonly esophageal atresia. Cardiac anomalies may be noted, and occasionally patients pres-ent with a constellation of defects as part of the VACTERLL syndrome (described earlier).Management of Patients With Imperforate Anus. Patients with imperforate anus are usually stable, and the diagnosis is readily apparent. Despite the obstruction, the abdomen is initially not distended, and there is rarely any urgency to intervene. The principles of management center around diagnosing the type of defect that is present (high vs. low), and evaluating the presence of associated anomalies. It may take up to 24 hours before the presence of a fistula on the skin is noted, and thus it is important to observe the neonate for some period of time before


Surgery_Schwartz

Surgery_Schwartz. the presence of associated anomalies. It may take up to 24 hours before the presence of a fistula on the skin is noted, and thus it is important to observe the neonate for some period of time before defini-tive surgery is undertaken. All patients should therefore have an orogastric tube placed and be monitored for the appearance of meconium in or around the perineum or in the urine. Investiga-tion for associated defects should include an US of the abdomen to assess for the presence of urinary tract anomaly. Other tests should include an echocardiogram and spinal radiographs. An US of the spine should be performed to look for the presence of a tethered cord. To further classify the location of the fistula as either “high” versus “low,” a lateral abdominal radiograph can be obtained with a radiopaque marker on the perineum. By placing the infant in the inverted position, the distance between the most distal extent of air in the rectum and the perineal surface can be measured. This study


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Surgery_Schwartz. marker on the perineum. By placing the infant in the inverted position, the distance between the most distal extent of air in the rectum and the perineal surface can be measured. This study is imprecise, however, and may add little to the overall management of these patients.The surgical management of infants with imperforate anus is determined by the anatomic defect. In general, when a low lesion is present, only a perineal operation is required without a colostomy. Infants with a high lesion require a colostomy in the newborn period, followed by a pull-through procedure at approximately 2 months of age. When a persistent cloaca is present, the urinary tract needs to be carefully evaluated at the time of colostomy formation to ensure that normal emptying can occur and to determine whether the bladder needs to be drained by means of a vesicostomy. If there is any doubt about the type of lesion, it is safer to perform a colostomy rather than jeopardize the infant’s long-term chances


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Surgery_Schwartz. the bladder needs to be drained by means of a vesicostomy. If there is any doubt about the type of lesion, it is safer to perform a colostomy rather than jeopardize the infant’s long-term chances for continence by an injudicious perineal operation.Brunicardi_Ch39_p1705-p1758.indd 173612/02/19 11:26 AM 1737PEDIATRIC SURGERYCHAPTER 39The type of pull-through procedure favored by most pedi-atric surgeons today is the posterior sagittal anorectoplasty (PSARP procedure), as described by Peña and DeVries. This involves placing the patient in the prone jack-knife position, dividing the levator ani and external sphincter complex in the midline posteriorly, dividing the communication between the gastrointestinal tract and the urinary tract, and bringing down the rectum after sufficient length is achieved. The muscles are then reconstructed and sutured to the rectum. The outcome of 1192 patients who had undergone this procedure has been reviewed by Peña and Hong. Seventy-five percent of


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Surgery_Schwartz. is achieved. The muscles are then reconstructed and sutured to the rectum. The outcome of 1192 patients who had undergone this procedure has been reviewed by Peña and Hong. Seventy-five percent of patients were found to have voluntary bowel movements, and nearly 40% were considered totally continent. As a rule, patients with high lesions demonstrate an increase incidence of incontinence, whereas those with low lesions are more likely to be consti-pated. Management of patients with high imperforate anus can be greatly facilitated using a laparoscopic assisted approach, in which the patient is operated on in the supine position, and the rectum is mobilized down to the fistulous connection to the bladder neck. This fistulous connection is then divided, and the rectum is completely mobilized down to below the peritoneal reflection. The operation then proceeds at the perineum, and the location of the muscle complex is determined using the nerve stimulator. A Veress needle is then advanced


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Surgery_Schwartz. down to below the peritoneal reflection. The operation then proceeds at the perineum, and the location of the muscle complex is determined using the nerve stimulator. A Veress needle is then advanced through the skin at the indicated site, with the laparoscope providing guidance to the exact intrapelvic orientation. Dilators are then placed over the Veress needle, the rectum is then pulled through this perito-neal opening, and an anoplasty is performed.JAUNDICEThe Approach to the Jaundiced InfantJaundice is present during the first week of life in 60% of term infants and 80% of preterm infants. There is usually accumula-tion of unconjugated bilirubin, but there may also be deposition of direct bilirubin. During fetal life, the placenta is the principal route of elimination of unconjugated bilirubin. In the newborn infant, bilirubin is conjugated through the activity of glucoronyl transferase. In the conjugated form, bilirubin is water soluble, which results in its excretion into the


Surgery_Schwartz

Surgery_Schwartz. bilirubin. In the newborn infant, bilirubin is conjugated through the activity of glucoronyl transferase. In the conjugated form, bilirubin is water soluble, which results in its excretion into the biliary system and then into the gastrointestinal tract. Newborns have a relatively high level of circulating hemoglobin and relative immaturity of the conjugating machinery. This results in a transient accumulation of bilirubin in the tissues, which is manifested as jaundice. Physi-ologic jaundice is evident by the second or third day of life and usually resolves within approximately 5 to 7 days. By definition, jaundice that persists beyond 2 weeks is considered pathologic.Pathologic jaundice may be due to biliary obstruction, increased hemoglobin load, or to liver dysfunction. The workup of the jaundiced infant therefore should include a search for the following possibilities: (a) obstructive disorders, including biliary atresia, choledochal cyst, and inspissated bile syndrome; (b)


Surgery_Schwartz

Surgery_Schwartz. of the jaundiced infant therefore should include a search for the following possibilities: (a) obstructive disorders, including biliary atresia, choledochal cyst, and inspissated bile syndrome; (b) hematologic disorders, including ABO incompatibility, Rh incompatibility, spherocytosis; (c) metabolic disorders, includ-ing α-1 antitrypsin deficiency, galactosemia; pyruvate kinase deficiency; and (d) congenital infection, including syphilis and rubella.Biliary AtresiaPathogenesis. Biliary atresia is a rare disease associated with significant morbidity and mortality. This disease is character-ized by a fibroproliferative obliteration of the biliary tree which progresses toward hepatic fibrosis, cirrhosis, and end-stage liver failure. The incidence of this disease is approximately 1 in 8000 to 1 in 18,000. The etiology of biliary atresia is likely multifac-torial. In the classic textbook, Abdominal Surgery of Infancy and Childhood, Ladd and Gross described the cause of biliary atresia as


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Surgery_Schwartz. 1 in 18,000. The etiology of biliary atresia is likely multifac-torial. In the classic textbook, Abdominal Surgery of Infancy and Childhood, Ladd and Gross described the cause of biliary atresia as an “arrest of development during the solid stage of bile duct formation.” Previously proposed theories on the eti-ology of biliary atresia have focused on defects in hepatogen-esis, prenatal vasculogenesis, immune dysregulation, infectious agents, and exposure to toxins. More recently, genetic mutations in the cfc1 gene, implicated in left-right axis determinations, were identified in patients with biliary atresia-splenic malforma-tion syndrome. Additionally, the detection of higher incidence of maternal microchimerism in the livers of males with biliary atresia has led to the suggestion that consequent expression of maternal antigens may lead to an autoimmune process leading to inflammation and obliteration of the biliary tree. Recent ani-mal studies strongly implicate perinatal exposure


Surgery_Schwartz

Surgery_Schwartz. consequent expression of maternal antigens may lead to an autoimmune process leading to inflammation and obliteration of the biliary tree. Recent ani-mal studies strongly implicate perinatal exposure to reovirus or rotavirus. Such viral exposure may lead to periportal inflamma-tion mediated by interferon-γ and other cytokines.Clinical Presentation. Infants with biliary atresia present with jaundice at birth or shortly thereafter. The diagnosis of biliary atresia is frequently not entertained by pediatricians in part because physiologic jaundice of the newborn is so common and biliary atresia is so uncommon. As such, it is not unusual for there to be a delay in diagnosis. However, infants with bili-ary atresia characteristically have acholic, pale gray appearing stools, secondary to obstructed bile flow. With further passage of time, these infants manifest progressive failure to thrive, and if untreated, develop stigmata of liver failure and portal hyper-tension, particularly


Surgery_Schwartz

Surgery_Schwartz. to obstructed bile flow. With further passage of time, these infants manifest progressive failure to thrive, and if untreated, develop stigmata of liver failure and portal hyper-tension, particularly splenomegaly and esophageal varices.The obliterative process of biliary atresia involves the common duct, cystic duct, one or both hepatic ducts, and the gallbladder, in a variety of combinations. The histopathology of patients with biliary atresia includes inflammatory changes within the parenchyma of the liver, as well as fibrous deposi-tion at the portal plates that is observed on trichrome staining of frozen tissue sections. In certain cases, bile duct prolifera-tion may be seen, a relatively nonspecific marker of liver injury. Approximately 25% of patients with biliary atresia have coin-cidental malformations, often associated with polysplenia, and may include intestinal malrotation, preduodenal portal vein, and intrahepatic vena cava.Diagnosis. In general, the diagnosis of biliary


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Surgery_Schwartz. malformations, often associated with polysplenia, and may include intestinal malrotation, preduodenal portal vein, and intrahepatic vena cava.Diagnosis. In general, the diagnosis of biliary atresia is made utilizing a combination of studies, as no single test is suffi-ciently sensitive or specific. Fractionation of the serum bilirubin is performed to determine if the associated hyperbilirubinemia is conjugated or unconjugated. Workup commonly includes the analysis of TORCH infection titers as well as viral hepatitis. Typically, a US is performed to assess the presence of other causes of biliary tract obstruction, including choledochal cyst. The absence of a gallbladder is highly suggestive of the diagno-sis of biliary atresia. However, the presence of a gallbladder does not exclude the diagnosis of biliary atresia because in approxi-mately 10% of biliary atresia patients, the distal biliary tract is patent and a gall bladder may be visualized, even though the proximal ducts are


Surgery_Schwartz

Surgery_Schwartz. the diagnosis of biliary atresia because in approxi-mately 10% of biliary atresia patients, the distal biliary tract is patent and a gall bladder may be visualized, even though the proximal ducts are atretic. It is important to note that the intrahe-patic bile ducts are never dilated in patients with biliary atresia. In many centers, a nuclear medicine scan using technetium 99m IDA (DISIDA), performed after pretreatment of the patient with phenobarbital, has proven to be an accurate and reliable study. Brunicardi_Ch39_p1705-p1758.indd 173712/02/19 11:26 AM 1738SPECIFIC CONSIDERATIONSPART IIIf radionuclide appears in the intestine, there is patency of the biliary tree, and the diagnosis of biliary atresia is excluded. If radionuclide is concentrated by the liver but not excreted despite treatment with phenobarbital, and the metabolic screen, particu-larly α1-antitrypsin determination, is normal, the presumptive diagnosis is biliary atresia. A percutaneous liver biopsy might


Surgery_Schwartz

Surgery_Schwartz. despite treatment with phenobarbital, and the metabolic screen, particu-larly α1-antitrypsin determination, is normal, the presumptive diagnosis is biliary atresia. A percutaneous liver biopsy might potentially distinguish between biliary atresia and other sources of jaundice such as neonatal hepatitis. When these tests point to or cannot exclude the diagnosis of biliary atresia, surgical exploration is warranted. At surgery, a cholangiogram may be performed if possible, using the gallbladder as a point of access. This may be performed using a laparoscope. The cholangio-gram demonstrates the anatomy of the biliary tree, determines whether extrahepatic bile duct atresia is present, and evaluates whether there is distal bile flow into the duodenum. The cholan-giogram may demonstrate hypoplasia of the extrahepatic biliary system. This condition is associated with hepatic parenchymal disorders that cause severe intrahepatic cholestasis, including α1-antitrypsin deficiency and biliary


Surgery_Schwartz

Surgery_Schwartz. of the extrahepatic biliary system. This condition is associated with hepatic parenchymal disorders that cause severe intrahepatic cholestasis, including α1-antitrypsin deficiency and biliary hypoplasia (Alagille’s syn-drome). Alternatively, a cursory assessment of the extrahepatic biliary tree may clearly delineate the atresia.Inspissated Bile Syndrome. This term is applied to patients with normal biliary tracts who have persistent obstructive jaun-dice. Increased viscosity of bile and obstruction of the canaliculi are implicated as causes. The condition has been seen in infants receiving parenteral nutrition, but it is also encountered in con-ditions associated with hemolysis, or in cystic fibrosis. In some instances, no etiologic factors can be defined. Neonatal hepatitis may present in a similar fashion to biliary atresia. This disease is characterized by persistent jaundice due to acquired biliary inflammation without obliteration of the bile ducts. There may be a viral etiology,


Surgery_Schwartz

Surgery_Schwartz. a similar fashion to biliary atresia. This disease is characterized by persistent jaundice due to acquired biliary inflammation without obliteration of the bile ducts. There may be a viral etiology, and the disease is usually self-limited. In this case, cholangiography is both diagnostic and therapeutic.Treatment. If the diagnosis of biliary atresia is confirmed intraoperatively, then surgical treatment is undertaken at the same setting. Currently, first-line therapy consists of creation of a hepatoportoenterostomy, as described by Kasai. The purpose of this procedure is to promote bile flow into the intestine. The procedure is based on Kasai’s observation that the fibrous tissue at the porta hepatis invests microscopically patent biliary duct-ules that, in turn, communicate with the intrahepatic ductal sys-tem (Fig. 39-26). Transecting this fibrous tissue at the portal Figure 39-26. Operative photograph showing Kasai portoenteros-tomy. Arrows denote the site of the anastomosis. Note


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Surgery_Schwartz. ductal sys-tem (Fig. 39-26). Transecting this fibrous tissue at the portal Figure 39-26. Operative photograph showing Kasai portoenteros-tomy. Arrows denote the site of the anastomosis. Note the engorged liver.Figure 39-27. Schematic illustration of the Kasai portoenteros-tomy for biliary atresia. An isolated limb of jejunum is brought to the porta hepatis and anastomosed to the transected ducts at the liver plate.plate, invariably encountered cephalad to the bifurcating portal vein, opens these channels and establishes bile flow into a surgi-cally constructed intestinal conduit, usually a Roux-en-Y limb of jejunum (Fig. 39-27). Some authors believe that an intussus-cepted antireflux valve is useful in preventing retrograde bile reflux, although the data suggest that it does not impact out-come. A liver biopsy is performed at the time of surgery to determine the degree of hepatic fibrosis that is present. The diameter of bile ducts at the portal plate is predictive of likeli-hood of


Surgery_Schwartz

Surgery_Schwartz. A liver biopsy is performed at the time of surgery to determine the degree of hepatic fibrosis that is present. The diameter of bile ducts at the portal plate is predictive of likeli-hood of long-term success of biliary drainage through the por-toenterostomy. Numerous studies also suggest that the likelihood of surgical success is inversely related to the age at the time of portoenterostomy. Infants treated prior to 60 days of life are more likely to achieve successful and long-term biliary drainage than older infants. Although the outlook is less favor-able for patients after the 12th week, it is reasonable to proceed with surgery even beyond this time point, as the alternative is certain liver failure. It is noteworthy that a significant number of patients have had favorable outcomes after undergoing portoen-terostomy despite advanced age at time of diagnosis.Bile drainage is anticipated when the operation is carried out early; however, bile flow does not necessarily imply cure.


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Surgery_Schwartz. after undergoing portoen-terostomy despite advanced age at time of diagnosis.Bile drainage is anticipated when the operation is carried out early; however, bile flow does not necessarily imply cure. Approximately one-third of patients remain symptom free after portoenterostomy, the remainder require liver transplantation due to progressive liver failure. Independent risk factors that predict failure of the procedure include bridging liver fibrosis at the time of surgery and postoperative cholangitic episodes. A review of the data of the Japanese Biliary Atresia Registry (JBAR), which 7Brunicardi_Ch39_p1705-p1758.indd 173812/02/19 11:26 AM 1739PEDIATRIC SURGERYCHAPTER 39includes the results of 1381 patients, showed that the 10-year survival rate was 53% without transplantation, and 66.7% with transplantation. A common postoperative complication is cholangitis. There is no effective strategy to completely eliminate this complication, and the effectiveness of long-term prophylactic


Surgery_Schwartz

Surgery_Schwartz. with transplantation. A common postoperative complication is cholangitis. There is no effective strategy to completely eliminate this complication, and the effectiveness of long-term prophylactic antibiotics has not been fully resolved. The Childhood Liver Research and Education Network (ChiLDREN, formerly the Biliary Atresia Research Consortium) is an active consortium of 15 children’s hospitals in the United States, funded by the National Institutes of Health (NIH) that studies rare cholestatic liver diseases of infants and children (http://childrennetwork.org). An NIH-funded, randomized, double-blinded, placebo-controlled trial designed to determine if adjuvant steroids improve outcome of infants undergoing Kasai portoenterostomy has been completed. This trial showed that among infants with biliary atresia who have undergone hepatoportoenterostomy, high-dose steroid therapy following surgery did not result in statistically significant treatment differences in bile drainage at 6


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Surgery_Schwartz. with biliary atresia who have undergone hepatoportoenterostomy, high-dose steroid therapy following surgery did not result in statistically significant treatment differences in bile drainage at 6 months, although a small clinical benefit could not be excluded. Steroid treatment was associated with earlier onset of serious adverse events in children with biliary atresia.Previous authors have published merits of revising the portoenterostomy in select patients if drainage of bile stops. Recently, Bondoc et al reported on their experience with revision of portoenterostomies. Specifically, the authors reported on 183 patients who underwent Kasai portoenterostomy for biliary atresia, of which 24 underwent revision for recurrence of nondrainage after successful bypass. Of the patients who underwent revision for nondrainage, 75% ultimately achieved drainage after the second procedure, of which nearly 50% survived long term with their native livers. The authors conclude that in selected


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Surgery_Schwartz. underwent revision for nondrainage, 75% ultimately achieved drainage after the second procedure, of which nearly 50% survived long term with their native livers. The authors conclude that in selected patients in which bile flow was established following the Kasai procedure and then lost, revision of the portoenterostomy is a reasonable treatment option with good success.Choledochal CystClassification. The term choledochal cyst refers to a spec-trum of congenital biliary tract disorders that were previously grouped under the name idiopathic dilation of the common bile duct. After the classification system proposed by Alonso-Lej, five types of choledochal cyst are described. Type I cyst is char-acterized by fusiform dilatation of the bile duct. This is the most common type and is found in 80% to 90% of cases. Type II choledochal cysts appear as an isolated diverticulum protruding from the wall of the common bile duct. The cyst may be joined to the common bile duct by a narrow stalk.


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Surgery_Schwartz. 80% to 90% of cases. Type II choledochal cysts appear as an isolated diverticulum protruding from the wall of the common bile duct. The cyst may be joined to the common bile duct by a narrow stalk. Type III choledochal cysts arise from the intraduodenal portion of the common bile duct and are also known as choledochoceles. Type IVA cysts consist of multiple dilatations of the intrahepatic and extra-hepatic bile ducts. Type IVB choledochal cysts are multiple dilatations involving only the extrahepatic bile ducts. Type V (Caroli’s disease) consists of multiple dilatations limited to the intrahepatic bile ducts.Choledochal cyst is most appropriately considered the pre-dominant feature in a constellation of pathologic abnormalities that can occur within the pancreato-biliary system. Frequently associated with choledochal cyst is an anomalous junction of the pancreatic and common bile ducts. The etiology of choledochal cyst is controversial. Babbit proposed an abnormal pancreatic and


Surgery_Schwartz

Surgery_Schwartz. associated with choledochal cyst is an anomalous junction of the pancreatic and common bile ducts. The etiology of choledochal cyst is controversial. Babbit proposed an abnormal pancreatic and biliary duct junction, with the formation of a “common channel” into which pancreatic enzymes are secreted. This process results in weakening of the bile duct wall by gradual enzymatic destruction, leading to dilatation, inflammation, and finally cyst formation. Not all patients with choledochal cyst demonstrate an anatomic common channel, which raises ques-tions regarding the accuracy of this model.Clinical Presentation. Choledochal cyst is more common in females than in males (4:1). Typically, these present in children beyond the toddler age group. The classic symptom triad consists of abdominal pain, mass, and jaundice. However, this complex is actually encountered in fewer than half of the patients. The more usual presentation is that of episodic abdominal pain, often recurring over the


Surgery_Schwartz

Surgery_Schwartz. pain, mass, and jaundice. However, this complex is actually encountered in fewer than half of the patients. The more usual presentation is that of episodic abdominal pain, often recurring over the course of months or years, and generally asso-ciated with only minimal jaundice that may escape detection. If left undiagnosed, patients may develop cholangitis or pancreatitis. Cholangitis may lead to the development of cirrhosis and portal hypertension. Choledochal cyst can present in the newborn period, where the symptoms are very similar to those of biliary atresia. Often neonates will have an abdominal mass at presentation.Diagnosis. Choledochal cyst is frequently diagnosed in the fetus at a screening prenatal US. In the older child or adoles-cent, abdominal US may reveal a cystic structure arising from the biliary tree. CT will confirm the diagnosis. These studies will demonstrate the dimensions of the cyst and define its rela-tionship to the vascular structures in the porta hepatis,


Surgery_Schwartz

Surgery_Schwartz. arising from the biliary tree. CT will confirm the diagnosis. These studies will demonstrate the dimensions of the cyst and define its rela-tionship to the vascular structures in the porta hepatis, as well as the intrahepatic ductal configuration. Endoscopic retrograde cholangiopancreatography (ERCP) is reserved for patients in whom confusion remains after evaluation by less invasive imag-ing modalities. Magnetic resonance cholangiopancreatography may provide a more detailed depiction of the anatomy of the cyst and its relationship to the bifurcation of the hepatic ducts and into the pancreas.Treatment. The cyst wall is composed of fibrous tissue and is devoid of mucosal lining. As a result, the treatment of cho-ledochal cyst is surgical excision followed by biliary-enteric reconstruction. There is no role for internal drainage by cys-tenterostomy, which leaves the cyst wall intact and leads to the inevitable development of cholangitis. Rarely, choledochal cyst can lead to the


Surgery_Schwartz

Surgery_Schwartz. There is no role for internal drainage by cys-tenterostomy, which leaves the cyst wall intact and leads to the inevitable development of cholangitis. Rarely, choledochal cyst can lead to the development of a biliary tract malignancy. This provides a further rationale for complete cyst excision.Resection of the cyst may be performed via open or laparo-scopic approach, and where possible, requires circumferential dis-section. The posterior plane between the cyst and portal vein must be carefully dissected to accomplish removal. The pancreatic duct, which may enter the distal cyst, is vulnerable to injury dur-ing distal cyst excision but can be avoided by avoiding entry into the pancreatic parenchyma. In cases were the degree of pericystic inflammation is dense, it may be unsafe to attempt complete cyst removal. In this instance, it is reasonable to dissect within the posterior wall of the cyst, which allows the inner lining of the back wall to be dissected free from the outer layer that


Surgery_Schwartz

Surgery_Schwartz. cyst removal. In this instance, it is reasonable to dissect within the posterior wall of the cyst, which allows the inner lining of the back wall to be dissected free from the outer layer that directly overlies the portal vascular structures. The lateral and anterior cyst, as well as the internal aspect of the back wall, is removed, yet the outer posterior wall remains behind. Cyst excision is accomplished, and the proximal bile duct is anastomosed to the intestinal tract typically via a Roux-en Y limb of jejunum. More recently, laparoscopic-assisted resections of choledochal cysts have been described. In these cases, the end-to-side jejunojeju-nostomy is performed extracorporeally, but the remainder of the procedure is completed utilizing minimally invasive techniques.The prognosis for children who have undergone com-plete excision of choledochal cyst is excellent. Complications include anastomotic stricture, cholangitis, and intrahepatic stone Brunicardi_Ch39_p1705-p1758.indd


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Surgery_Schwartz. children who have undergone com-plete excision of choledochal cyst is excellent. Complications include anastomotic stricture, cholangitis, and intrahepatic stone Brunicardi_Ch39_p1705-p1758.indd 173912/02/19 11:26 AM 1740SPECIFIC CONSIDERATIONSPART IIformation. These complications may develop a long time after surgery has been completed.DEFORMITIES OF THE ABDOMINAL WALLEmbryology of the Abdominal WallThe abdominal wall is formed by four separate embryologic folds: cephalic, caudal, right, and left lateral folds. Each of these is com-posed of somatic and splanchnic layers and develops toward the anterior center portion of the coelomic cavity, joining to form a large umbilical ring that surrounds the two umbilical arteries, the vein, and the yolk sac or omphalomesenteric duct. These struc-tures are covered by an outer layer of amnion, and the entire unit composes the umbilical cord. Between the 5th and tenth weeks of fetal development, the intestinal tract undergoes rapid growth


Surgery_Schwartz

Surgery_Schwartz. struc-tures are covered by an outer layer of amnion, and the entire unit composes the umbilical cord. Between the 5th and tenth weeks of fetal development, the intestinal tract undergoes rapid growth outside the abdominal cavity within the proximal portion of the umbilical cord. As development is completed, the intestine gradu-ally returns to the abdominal cavity. Contraction of the umbilical ring completes the process of abdominal wall formation.Failure of the cephalic fold to close results in sternal defects such as congenital absence of the sternum. Failure of the caudal fold to close results in exstrophy of the bladder and, in more extreme cases, exstrophy of the cloaca. Interruption of central migration of the lateral folds results in omphalocele. Gastroschisis, originally thought to be a variant of omphalocele, possibly results from a fetal accident in the form of intrauterine rupture of a hernia of the umbilical cord, although other hypoth-eses have been advanced.Umbilical


Surgery_Schwartz

Surgery_Schwartz. to be a variant of omphalocele, possibly results from a fetal accident in the form of intrauterine rupture of a hernia of the umbilical cord, although other hypoth-eses have been advanced.Umbilical HerniaFailure of the umbilical ring to close results in a central defect in the linea alba. The resulting umbilical hernia is covered by nor-mal umbilical skin and subcutaneous tissue, but the fascial defect allows protrusion of abdominal contents. Hernias less than a cen-timeter in size at the time of birth usually will close spontaneously by 4 to 5 years of life and in most cases should not undergo early repair. Sometimes the hernia is large enough that the protrusion is disfiguring and disturbing to both the child and the family. In such circumstances, early repair may be advisable (Fig. 39-28).Figure 39-28. Umbilical hernia in a 1-year-old female.Umbilical hernias are generally asymptomatic protrusions of the abdominal wall. They are generally noted by parents or physicians shortly


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Surgery_Schwartz. 39-28).Figure 39-28. Umbilical hernia in a 1-year-old female.Umbilical hernias are generally asymptomatic protrusions of the abdominal wall. They are generally noted by parents or physicians shortly after birth. All families of patients with umbilical hernia should be counseled about signs of incarcera-tion, which is rare in umbilical hernias and more common in smaller (1 cm or less) rather than larger defects. Incarceration presents with abdominal pain, bilious emesis, and a tender, hard mass protruding from the umbilicus. This constellation of symp-toms mandates immediate exploration and repair of the hernia to avoid strangulation. More commonly, the child is asymptomatic and treatment is governed by the size of the defect, the age of the patient, and the concern that the child and family have regard-ing the cosmetic appearance of the abdomen. When the defect is small and spontaneous closure is likely, most surgeons will delay surgical correction until 5 years of age. If closure


Surgery_Schwartz

Surgery_Schwartz. have regard-ing the cosmetic appearance of the abdomen. When the defect is small and spontaneous closure is likely, most surgeons will delay surgical correction until 5 years of age. If closure does not occur by this time or a younger child has a very large or symp-tomatic hernia, it is reasonable to proceed to repair.Repair of uncomplicated umbilical hernia is performed under general anesthesia as an outpatient procedure. A small curving incision that fits into the skin crease of the umbilicus is made, and the sac is dissected free from the overlying skin. The fascial defect is repaired with permanent or long-lasting absorb-able, interrupted sutures that are placed in a transverse plane. The skin is closed using subcuticular sutures. The postoperative recovery is typically uneventful and recurrence is rare, but it is more common in children with elevated intraabdominal pres-sures, such as those with a VP shunt.Patent UrachusDuring the development of the coelomic cavity, there is free


Surgery_Schwartz

Surgery_Schwartz. recurrence is rare, but it is more common in children with elevated intraabdominal pres-sures, such as those with a VP shunt.Patent UrachusDuring the development of the coelomic cavity, there is free communication between the urinary bladder and the abdominal wall through the urachus, which exits adjacent to the omphalo-mesenteric duct. Persistence of this tract results in a communi-cation between the bladder and the umbilicus. The first sign of a patent urachus is moisture or urine flow from the umbilicus. Recurrent urinary tract infection can result. The urachus may be partially obliterated, with a remnant beneath the umbilicus in the extraperitoneal position as an isolated cyst that may be identi-fied by US. A urachal cyst usually presents as an inflammatory mass inferior to the umbilicus. Initial treatment is drainage of the infected cyst followed by cyst excision as a separate proce-dure once the inflammation has resolved.In the child with a persistently draining umbilicus, a


Surgery_Schwartz

Surgery_Schwartz. Initial treatment is drainage of the infected cyst followed by cyst excision as a separate proce-dure once the inflammation has resolved.In the child with a persistently draining umbilicus, a diag-nosis of patent urachus should be considered. The differential diagnosis includes an umbilical granuloma, which generally responds to local application of silver nitrate. The diagnosis of patent urachus is confirmed by umbilical exploration. The ura-chal tract is excised and the bladder is closed with an absorbable suture. A patent vitelline duct may also present with umbilical drainage. In this circumstance, there is a communication with the small intestine, often at the site of a Meckel’s diverticulum. Treatment includes umbilical exploration with resection of the duct remnant (Fig. 39-29).OmphalocelePresentation. Omphalocele refers to a congenital defect of the abdominal wall in which the bowel and solid viscera are covered by peritoneum and amniotic membrane (Fig. 39-30). The umbil-ical


Surgery_Schwartz

Surgery_Schwartz. refers to a congenital defect of the abdominal wall in which the bowel and solid viscera are covered by peritoneum and amniotic membrane (Fig. 39-30). The umbil-ical cord inserts into the sac. Omphalocele can vary from a small defect with intestinal contents to giant omphalocele in which the abdominal wall defect measures 4 cm or more in diameter and contains liver. The overall incidence is approximately 1 in 5000 Brunicardi_Ch39_p1705-p1758.indd 174012/02/19 11:26 AM 1741PEDIATRIC SURGERYCHAPTER 39Figure 39-29. Patent vitelline duct. Note the communication between the umbilicus and the small bowel at the site of a Meckel’s diverticulum.Figure 39-30. Giant omphalocele in a newborn male.live births, with 1 in 10,000 that are giant omphaloceles. Omphalocele occurs in association with special syndromes such as exstrophy of the cloaca (vesicointestinal fissure), the Beckwith-Wiedemann constellation of anomalies (macroglos-sia, macrosomia, hypoglycemia, and visceromegaly and


Surgery_Schwartz

Surgery_Schwartz. with special syndromes such as exstrophy of the cloaca (vesicointestinal fissure), the Beckwith-Wiedemann constellation of anomalies (macroglos-sia, macrosomia, hypoglycemia, and visceromegaly and omphalocele) and Cantrell’s Pentalogy (lower thoracic wall malformations [cleft sternum], ectopia cordis, epigastric omphalocele, anterior midline diaphragmatic hernia and cardiac anomalies). There is a 60% to 70% incidence of associated anomalies, especially cardiac (20–40% of cases) and chromo-somal abnormalities. Chromosomal anomalies are more common in children with smaller defects. Omphalocele is associated with prematurity (10–50% of cases) and intrauterine growth restriction (20% of cases).Treatment. Immediate treatment of an infant with omphalocele consists of attending to the vital signs and maintaining the body 8temperature. A blood glucose should be evaluated because of the association with Beckwith-Wiedemann. The omphalocele should be covered to reduce fluid loss, but moist


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Surgery_Schwartz. signs and maintaining the body 8temperature. A blood glucose should be evaluated because of the association with Beckwith-Wiedemann. The omphalocele should be covered to reduce fluid loss, but moist dressings may result in heat loss and are not indicated. No pressure should be placed on the omphalocele sac in an effort to reduce its contents because this maneuver may increase the risk of rupture of the sac or may interfere with abdominal venous return. Prophylac-tic broad-spectrum antibiotics should be administered in case of rupture. The subsequent treatment and outcome is determined by the size of the omphalocele. In general terms, small to medium-sized defects have a significantly better prognosis than extremely large defects in which the liver is present. In these cases, not only is the management of the abdominal wall defect a significant challenge, but these patients often have concomitant pulmonary insufficiency that can lead to significant morbidity and mortality. If possible,


Surgery_Schwartz

Surgery_Schwartz. management of the abdominal wall defect a significant challenge, but these patients often have concomitant pulmonary insufficiency that can lead to significant morbidity and mortality. If possible, and if the pulmonary status will permit it, a primary repair of the omphalocele should be undertaken. This involves resection of the omphalocele membrane and closure of the fas-cia. A layer of prosthetic material may be required to achieve closure. In infants with a giant omphalocele, the defect cannot be closed primarily because there is not adequate intraperitoneal domain to reduce the viscera (see Fig. 39-30). Some infants may have associated congenital anomalies that complicate surgical repair, and because cardiac anomalies are common, an echocar-diogram should be obtained prior to any procedure. If repair is contraindicated, such as with a very large defect, a nonopera-tive approach can be used. The omphalocele sac can be treated with topical treatments, which serve to harden the sac


Surgery_Schwartz

Surgery_Schwartz. If repair is contraindicated, such as with a very large defect, a nonopera-tive approach can be used. The omphalocele sac can be treated with topical treatments, which serve to harden the sac to allow for more protective coverage where muscle and skin cannot be used given the large defect. Various authors describe success with iodine-containing solutions, silver sulfadiazine, or saline, and some surgeons rotate these solutions because of the impact of iodine on the thyroid and the difficulty of cleaning off all of the silver sulfadiazine and its association with leukopenia. It typically takes 2 to 3 months before reepithelialization occurs. In the past, mercury compounds were used, but they have been discontinued because of associated systemic toxicity. After epi-thelialization has occurred, attempts should be made to achieve closure of the anterior abdominal wall but may be delayed by associated pulmonary insufficiency. Such procedures typically require complex measures to achieve


Surgery_Schwartz

Surgery_Schwartz. attempts should be made to achieve closure of the anterior abdominal wall but may be delayed by associated pulmonary insufficiency. Such procedures typically require complex measures to achieve skin closure, including the use of biosynthetic materials or component separation. In cases of giant omphalocele, prolonged hospitalization is typical. If the base is very narrow—which can occur even for babies with very large omphaloceles—it may be wise to open the base in order to allow the abdominal contents and the liver to reenter the abdominal cavity, and thereby achieve abdominal domain. This approach will, by necessity, require sewing in some synthetic material in order to achieve fascial closure, and prolonged hos-pitalization will be required to allow for skin coverage to occur. These patients require high amounts of caloric support, given the major demands for healing.GastroschisisPresentation. Gastroschisis represents a congenital anom-aly characterized by a defect in the anterior


Surgery_Schwartz

Surgery_Schwartz. require high amounts of caloric support, given the major demands for healing.GastroschisisPresentation. Gastroschisis represents a congenital anom-aly characterized by a defect in the anterior abdominal wall through which the intestinal contents freely protrude. Unlike omphalocele, there is no overlying sac, and the size of the defect is usually <4 cm. The abdominal wall defect is located at the junction of the umbilicus and normal skin, and is almost always to the right of the umbilicus (Fig. 39-31). The umbilicus becomes partly detached, allowing free communication with the Brunicardi_Ch39_p1705-p1758.indd 174112/02/19 11:26 AM 1742SPECIFIC CONSIDERATIONSPART IIFigure 39-31. Gastroschisis in a newborn. Note the location of the umbilical cord and the edematous, thickened bowel.Figure 39-32. Prenatal ultrasound of a 30-week gestation age fetus with a gastroschisis. Arrows point to the bowel outside within the amniotic fluid.Figure 39-33. Use of a silo in a patient with a


Surgery_Schwartz

Surgery_Schwartz. 39-32. Prenatal ultrasound of a 30-week gestation age fetus with a gastroschisis. Arrows point to the bowel outside within the amniotic fluid.Figure 39-33. Use of a silo in a patient with a gastroschisis to allow for the bowel wall edema to resolve so as to facilitate closure of the abdominal wall.abdominal cavity. The appearance of the bowel provides some information with respect to the in-utero timing of the defect. The intestine may be normal in appearance, suggesting that the rupture occurred relatively late during the pregnancy. More commonly, however, the intestine is thick, edematous, discol-ored, and covered with exudate, implying a more longstanding process. Progression to full enteral feeding is usually delayed, with diminished motility that may be related to these changes.Unlike infants born with omphalocele, associated anoma-lies are not usually seen with gastroschisis except for a 10% rate of intestinal atresia. This defect can readily be diagnosed on prenatal US (Fig.


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Surgery_Schwartz. infants born with omphalocele, associated anoma-lies are not usually seen with gastroschisis except for a 10% rate of intestinal atresia. This defect can readily be diagnosed on prenatal US (Fig. 39-32). There is no advantage to perform-ing a cesarean section instead of a vaginal delivery. In a decade long retrospective review, early deliver did not affect the thick-ness of bowel peel, yet patients delivered before 36 weeks had significantly longer length of stay in the hospital and time to enteral feeds. Based upon these findings, it is thought that fetal well-being should be the primary determinant of delivery for gastroschisis.Treatment. All infants born with gastroschisis require urgent surgical treatment. Of equal importance, these infants require vigorous fluid resuscitation in the range of 160 to 190 cc/kg per day to replace significant evaporative fluid losses. In many instances, the intestine can be returned to the abdominal cavity, and a primary surgical closure of the


Surgery_Schwartz

Surgery_Schwartz. the range of 160 to 190 cc/kg per day to replace significant evaporative fluid losses. In many instances, the intestine can be returned to the abdominal cavity, and a primary surgical closure of the abdominal wall is per-formed. Some surgeons believe that they facilitate primary closure with mechanical stretching of the abdominal wall, thor-ough orogastric suctioning with foregut decompression, rectal irrigation, and evacuation of meconium. Care must be taken to prevent markedly increased abdominal pressure during the reduction, which will lead to compression of the inferior vena cava, respiratory embarrassment, and abdominal compartment syndrome. To avoid this complication, it is helpful to moni-tor the bladder or airway pressures during reduction. In infants whose intestine has become thickened and edematous, it may be impossible to reduce the bowel into the peritoneal cavity in the immediate postnatal period. Under such circumstances, a plastic spring-loaded silo can be placed


Surgery_Schwartz

Surgery_Schwartz. thickened and edematous, it may be impossible to reduce the bowel into the peritoneal cavity in the immediate postnatal period. Under such circumstances, a plastic spring-loaded silo can be placed onto the bowel and secured beneath the fascia or a sutured silastic silo constructed. The silo covers the bowel and allows for graduated reduc-tion on a daily basis as the edema in the bowel wall decreases (Fig. 39-33). It is important to ensure that the silo-fascia junc-tion does not become a constricting point or “funnel,” in which case the intestine will be injured upon return to the peritoneum. In this case, the fascial opening must be enlarged. Surgical clo-sure can usually be accomplished within approximately 1 to 2 weeks. A prosthetic piece of material may be required to bring the edges of the fascia together. If an atresia is noted at the time of closure, it is prudent to reduce the bowel at the first operation and return after several weeks once the edema has resolved to correct