Follow-up \200 Respiratory morbidity in the early years after OA/TOF repair is relatively high, particular ly in the winter months. Consider admitting these children during respiratory infections. O bstruction of the esophagus by food boluses is common in toddlers and young children after OA repair. Usually, it is caused by meat that has not been chewed. Refer for urgent oesopha goscopy. OA + TOF Isolated OA OA + double TOF Isolated H-TOF Fig. 23.2 Types of OA/TOF. 23_McClure_23.indd 849 11/14/2012 3:30:19 PM CHAPTER 23 Pediatric surgery 850 Congenital abnormalities: esophagus Oesophageal stricture Oesophageal strictures in childre n may be congenital (5%) or acquired (95%). Strictures may be acquired as a result of re \202 ux oesophagitis, caustic ingestion, or following repair of OA. Congenital oesophageal strictures most commonly affect the middle and distal third of the esophagus and rarely cau se symptoms in the neonatal period. They may be due to: \200 \200 \200 membranous diaphragm; segmental submucosal \201 brosis; presence of ectopic tracheobronch ial rests. Presentation Strictures present with: \200 \200 \200 regurgitation of undigested food; bolus obstruction; failure to thrive. Diagnosis \200 \200 Barium swallow. Oesophagoscopy. Treatment. \200 \200 Peptic strictures are an absolute indication for anti-re \202 ux surgery. Congenital stric tures may respond to dilatation but resection or oesophageal replacement is often necessary . Caustic ingestion \200 \200 \200 \200 Acute Endoscopy: Feeding Chronic children require oesophageal replacement. phase: resuscitate and support with IV \202 uids and antibiotics. to con \201 rm the severity of the burn. gastrostomy: in severe strictures. phase: serial oesophageal dilatation is performed, but m any 23_McClure_23.indd 850 11/14/2012 3:30:19 PM CONGENITAL ABNORMALITIES: LUNG 851 Congenital abnormalities: lung Congenital cystic adenomatoid malformation (CAM) CAM is a co ngenital malformation of the lung bud characterized by dys- plasia of respiratory epitheliu m. The majority of CAMs are now diagnosed prenatally by US and high-risk cases will be asso ciated with hydrops. Symptomatic CAMs should be resected. \200 Large CAMs present at birth with respiratory distress that is managed along conventional li nes. Small CAMs will be asymptomatic at birth, but may present in early childhood with pulm onary sepsis. Sequestration Pulmonary sequestrations are segments of lung parenchyma with an anomalous bl ood supply from the aorta. There may be an abnormal bron- chial connection with the foregut or tracheobronchial tree. The majority are detected prenatally and the management is resec tion. \200 Large sequestrations will present at birth with respiratory distress or with heart failure from high \202 ow through the feeding vessel. Sequestrations may present in infancy or ch ildhood with pulmonary sepsis. Congenital lobar emphysema (CLE) CLE is an unusual lung bud anomaly characterized by massiv e air trapping in the emphysematous lobe. This compresses the surrounding normal lung and m ay result in mediastinal shift. \200 CLE presenting with progressive respiratory distress within the \201 rst few weeks or mon ths of life nearly always require lobectomy. In the acute phase positive pressure ventilati on may produce rapid worsening of the emphysema. Lobar emphysema identi \201 ed on CXR in the absence of symptoms will need close follow-up, and surgery may be avoided. 23_McClure_23.indd 851 11/14/2012 3:30:19 PM CHAPTER 23 Pediatric surgery 852 Congenital abnormalities: chest Congenital diaphragmatic hernia See b p.844. The incidence of CDH is 1/2400. The main problem is not the diaphragmatic hernia, but rather the associat ed pulmonary hypoplasia that is often severe and determines prognosis. The most common type of diaphragmatic defect is posterolateral (Bochdalek) and left-sided, occur- ring in 90% ( see Figs 23.3 and 23.4). \200 screening: most CDHs are identi \201 ed on antenatal US, but the Antenatal prognosis for these fetuses is poor (i.e. 20% survive). Birth: if the diagnosis i s not made antenatally and the baby presents at birth, clinical \201 ndings may include r espiratory distress, scaphoid abdomen, and apparent dextrocardia. The prognosis for surviva l is 760%. Coincidental: including most anterior (Morgagni) defects. The prognosis is excel lent. 710% of CDHs are discovered during early childhood, Neonatal management \200 Initial management consists of sedation, paralysis, endotracheal intubation, and mechanical ventilation with 100% O2. NGT placement and avoid bag \200\223mask \200\223valve ventilati on. If oxygenation is good and pulmonary hypoplasia is not severe, repair of the diaphragma tic defect is undertaken after a few days either by primary suture or insertion of a prosth etic patch. \200 Hiatus hernia (HIH) HIH refers to herniation of the stomach into the chest through the oe- sophageal hiatus in the diaphragm. The lower oesophageal sphincter also moves and becomes i ncompetent. Most children with HIH present with gastro-oesophageal re \202 ux (GOR). Two t ypes of hiatus hernia are recog- nized (Fig. 23.5): \200 \200 sliding (common); rolling or paraoesophageal (rare). Management \200 \200 \200 Diagnosis is made radiologically by barium meal. Treatment comprises management of the GOR, initially medically. Surgery is reserved for children who fail to respond to medication, c omplicated re \202 ux (e.g. peptic strictures), and paraoesophageal hernias (because of th e risk of incarceration and infarction of the herniated stomach). Surgery involves repair o f the hiatus hernia and a fundoplication to prevent GOR. 23_McClure_23.indd 852 11/14/2012 3:30:19 PM CONGENITAL ABNORMALITIES: CHEST 853 Anterior (Morgagni) hernia Posterolateral (Bochdalek) hernia Fig. 23.3 Types of diaphragmatic hernia. Apparent dextrocardia because mediastinum displaced into right thorax Signs of respiratory distress : tachypnoea cyanosis grunting Bowel sounds may be audible in chest (uncommon) Scaphoid abdomen because bowel in chest Fig. 23.4 Clinical features of CDH. Sliding hiatus hernia (common) Rolling hiatus hernia (rare) Fig. 23.5 Types of hiatus hernia. 23_McClure_23.indd 853 11/14/2012 3:30:20 PM CHAPTER 23 Pediatric surgery 854 Idiopathic hypertrophic pyloric stenosis The incidence of idiopathic hypertrophic pyloric s tenosis (IHPS) is 73/1000 live births. Boys are affected more frequently than girls and IHP S is more common in Whites than in dark-skinned races. The pylorus enlarges as a result of hypertrophy of the circular muscle to produce the typical \200\230tumor \200\231. The caus e remains unknown. Familial occurrence is well docu- mented, particularly in girls. Clinica l features (Fig. 23.6) \200 Vomiting: vomitus is always non-bilious, but it may contain altered blood ( \200\230coffee ground \200\231) or fresh blood from oesophagitis. Vomiting occurs within an hour of feedin g and the baby is immediately hungry. Vomiting may not be projectile in babies who present early ( \201 rst or second week); they are often misdiagnosed as suffering from GOR. Const ipation Dehydration IHPS is rare beyond 12wks of age. projectile, starting in the third or fourth week of life. The \200 \200 is common due to reduced \202 uid intake. , malnutrition, and jaundice are late signs. Diagnosis \200 Test the examiner palpates the baby \200\231s abdomen. This is best conducted with the baby resting on the mother \200\231s lap, cradled on her left arm. The examiner sits opposite t he mother, on the baby \200\231s left. Visible waves of gastric peristalsis may be seen pas sing across the upper abdomen. The pyloric tumor is usually easiest to feel either early in the feed or after the baby has vomited. 60 \200\22390% tumors are palpable. The thickened pylorus is palpable as a \201 rm, \200\230olive-shaped \200\231 mass, just above and to the right of the umbilicus during a \200\230test feed \200\231. US: diagnosis. Biochemistr y: the biochemical abnormality of IHPS is a hypochloraemic, hypokalaemic metabolic alkalosi s (Fig. 23.7). Assess degree of alkalosis at presentation and monitor correction prior to s urgery. feed: the baby is allowed to feed from the breast or bottle whilst if a tumor cannot be felt, US will usually con \201 rm or exclude the Pre-operative management \200 IV \200 Rehydrate and correct the alkalosis before surgery. \202 uids should be started. 0.45% Saline with 5% dextrose and 20mmol/L potassium chloride at 120mL/kg/day. Feeds: Electrolytes they return to normal (usu ally 24 \200\22348h). Blood glucose: should be monitored. Surgery \200 \200 withhold. The stomach should be emptied with a NGT. and capillary blood pH: should be checked regularly until Ramstedt \200\231s This involves splitting the thickened pyloric muscle. Complications incl ude perforation of the mucosa, which is not serious provided it is recognized and repaired, and wound infection. feeds are usually withheld overnight. Transient post-operative Oral v omiting is common but invariably settles within 36h. There are no long-term sequelae. pyloromyotomy: the treatment of choice (Fig. 23.8). 23_McClure_23.indd 854 11/14/2012 3:30:20 PM IDIOPATHIC HYPERTROPHIC PYLORIC STENOSIS 855 Signs of mild-moderate dehydration (sunken fontanelle, dry tongue) Projectile, non-bilious vomiting. Hungry active baby (except in very advanced cases) Visible peristalisis over stomach Palpable pyloric tumor (feels like an olive or marble) Dry nappies, constipation Fig. 23.6 Clinical signs of pyloric stenosis. Hydrogen chloride loss from vomiting Renal compensation by maximizing bicarbonate reabsorbtion Exchange of K+ and Na+ for hydrogen ions in distal convoluted tubule Results in hypochloraemic metabolic alkalosis Fig. 23.7 Biochemical abnormalities in pyloric stenosis. Pyloric mucosa bulges through the myotomy Fig. 23.8 Ramstedt \200\231s operation. 23_McClure_23.indd 855 11/14/2012 3:30:20 PM CHAPTER 23 Pediatric surgery 856 Ingested foreign bodies See also b pp.51, 857. Swallowed foreign bodies are fairly common i n young children. The incident may have been witnessed. Alternatively, the child may presen t with: \200 \200 \200 dribbling; regurgitation; occasionally cough and stridor. Diagnosis Chest X-ray: the majority of ingested foreign bodies are radio-opaque (coins). Management \200 Oesophageal: if the foreign body is in the esophagus it should be removed within 24hr, usually by oesophagoscopy. Button batteries in the esophagus must be retrieve d or pushed down into the stomach within a few hours of ingestion. Electrolytic ulceration of the esophagus occurs rapidly and this may lead to perforation or \201 stulation into t he tracheal or aorta. Below invariably pass spontaneously per rectum and all that is requir ed is reassurance. Serial radiographs are unnecessary. The only proviso is a child who has had previous abdominal surgery in which case adhesions may impede passage of the object: \200 the diaphragm: if the foreign body is below the diaphragm it will Parents should be asked to examine the child \200\231s stools for the foreign body. Colicky abdominal pain and vomiting (i.e. possible signs of intestinal obstruction) warrant review and a repeat X-ray. Provided the child remains asymptomatic, surgery to retrieve the objec t should be deferred for several months. Button the same way as other ingested foreign bodi es. The battery will pass spontaneously long before it disintegrates. batteries below the diaphragm should be treated in exactly 23_McClure_23.indd 856 11/14/2012 3:30:21 PM BEZOARS 857 Bezoars Bezoars are FB concretions composed of hair (trichobezoar) or vegetable matter (phy tobezoar). The bezoar forms in the stomach and may extend into the small bowel. Bezoars are most commonly seen in young girls who present with: \200 weight loss; \200 vomiting; \200 abdominal pain; \200 anemia. Diagnosis \200 \200 An abdominal mass may be palpable. Barium meal or endoscopy will con \201 rm the abnormali ty. Surgical treatment \200 \200 Large Smaller bezoars: open surgical removal is necessary. bezoars: endoscopic removal. 23_McClure_23.indd 857 11/14/2012 3:30:21 PM CHAPTER 23 Pediatric surgery 858 Midgut malrotation and volvulus See Fig. 23.9 and b p.845. During the \201 rst trimester of intrauterine development the fetal midgut transiently herniates into the umbilical cord. As this reduces, the mesentery normally rotates to bring the cae- cum to lie in the right iliac fossa and duodenojejunal \202 exure (DJF) to lie to the left of the midline. The mi dgut mesentery thus extends diagonally across the back of the abdominal cavity and provides a broad stable pedi- cle for the SMA to supply the bowel. Malrotation is a failure of this normal rotation that leaves the caecum high in the right upper quadrant and DJF mobile in midline. The result is a narrow base for the midgut mesentery and a narrow mobile pedicle t hrough which the SMA runs. Malrotation is usually asymptomatic and only detected by contras t meal and follow through. Midgut malrotation \200 \200 Midgut malrotation predisposes to midgut volvulus. To prevent this complication, surgical c orrection of a malrotation is advised using Ladd \200\231s procedure. An incidental appendi cectomy is usually performed. Midgut volvulus \200 \200 This is a catastrophic event that occurs without warning. The immediate effect is high inte stinal obstruction at duodenal level that is rapidly followed by infarction of the entire m idgut. Symptoms \200 \200 \200 Bile-stained vomiting. Circulatory collapse. Tender abdomen. Diagnosis \200 AXR (Fig. 23.10). May appear similar to duodenal atresia with a \200\230double bubble \200 \231 and a paucity of gas elsewhere in the abdomen. The diagnosis is con \201 rmed by an u rgent (even middle of the night) upper GI contrast study. Surgical treatment \200 \200 \200 Immediate laparotomy to untwist the volvulus. If the bowel is healthy a Ladd \200\231s proc edure is performed. If bowel viability is doubtful a second look laparotomy may be necessar y after 24hr. Frequently, there is massive intestinal necrosis and the child is left with a very short gut in which case long-term IV feeding is required. 23_McClure_23.indd 858 11/14/2012 3:30:21 PM MIDGUT MALROTATION AND VOLVULUS 859 Normal Malrotation Mid-gut volvulus Duodenal obstruction Broad stable base to midgut mesentery. DJ flexure to left of midline, caecum in RIF Narrow base to midgut mesentery predisposes to volvulus Volvulus around base of midgut causes bowel obstruction and mesenteric ischaemia leading to infarction of the midgut Fig. 23.9 Intestinal rotation and volvulus. RIF, Right iliac fossa; DJF, duodenojejunal \202 exure. Dilated stomach and duodenum (obstruction) No other air-fluid levels in the bowel, just a few small pockets of residual gas in small/l arge bowel Fig. 23.10 Features of volvulus on AXR. 23_McClure_23.indd 859 11/14/2012 3:30:21 PM CHAPTER 23 Pediatric surgery 860 Intussusception Intussusception typically affects infants between 6 and 18mths of age. The incidence is 1/500 children. The majority of intussusceptions occur in association with vir al gastroenteritis. \200 Enlarged Peyer \200\231s patch in the ileum acts as the invaginates into the distal bowel. Intussusceptions in older children and adults are more likely to be due to a pathological l ead point, e.g. a polyp or Meckel \200\231s diverticulum. lead point that then Intussusception causes a small bowel obstruction. The intussuscepted bowel becomes engorged , which causes rectal bleeding, and eventually gangrenous. Following this, perforation and peritonitis will occur. The most common site for an intussusception is ileocolic (Fig. 23.1 1) followed by ileo-ileal. Small bowel intussusception may occur as a post-operative compli cation in infants, typically following nephrectomy. Presentation The typical presentation of an intussusception in an infant is as follows: \200 \200 \200 Spasms of colic associated with pallor, screaming, and drawing-up legs. The child falls asl eep between episodes. Later, as the intestinal obstruction progresses, bile-stained vomitin g develops and rectal bleeding, (i.e. \200\230red currant jelly stools \200\231). The chil d will appear ill, listless, and dehydrated. In late cases circulatory shock or peritonitis will be present. \200 Assessment \200 In 30% of cases the intussusception will be palpable as a sausage- shaped abdominal mass. B lood may be noted on rectal examination. AXR: be visible. US: \200 small bowel obstruction and occasionally a soft tissue mass will con \201 rms the diagnosis by showing a characteristic \200\230target sign \200\231. Management \200 Resuscitation: perfusion Antibiotics Analgesia . NGT Radiological peri tonitis, and facilities for immediate surgery are available, the treatment of choice is for an expert pediatric radiologist to reduce the intussusception pneumatically by rectal insu f \202 ation of air under \202 uoroscopic control. The risks of this procedure are incom plete reduction and perforation. The latter can be particularly dangerous as a tension pneu moperitoneum develops very rapidly. Laparotomy: because of concern about a gangrenous intus susception, laparotomy often large volumes of IV \202 uid are required to restore \200 \200 \200 passed if the infant is vomiting. reduction: provided that there is no evidence of if pneumatic reduction fails, or is contraindicated 23_McClure_23.indd 860 11/14/2012 3:30:22 PM INTUSSUSCEPTION 861 is necessary. The distal bowel is gently compressed to reduce the intussusception. If this is not successful then the intussusception is resected. There is a recurrence rate about 10 % whether the intussusception is treated radiologically or by surgery. Further recurrence s hould raise the question of a pathological lead point. Hepatic flexure Intussuscepted ileum becomes oedematous with bleeding from the mucosa Blood vessels become drawn into the intussusception Appendix drawn into the intussusception Small bowel obstruction Fig. 23.11 Ileocolic intussusception. 23_McClure_23.indd 861 11/14/2012 3:30:22 PM CHAPTER 23 Pediatric surgery 862 Duodenal atresia The incidence of DA is 1/5000 live births. \200 \200 \200 One-third of babies with DA have trisomy 21. Babies with DA present at birth with bile-stai ned vomiting. AXR shows \200\230double bubble \200\231 sign of gas in stomach and proximal duodenum (Fig. 23.12). Surgical treatment consists of side-to-side duodenoduodenostomy. Th e prognosis is excellent. Small bowel atresias The incidence of small bowel atresia is 1/3000 live births. The etiolo gy is thought to be vascular. The pathology of small bowel atresias varies (depending on ho w deep in the mesentery the vascular accident occurs) from an atresia in continuity with a mucosal membrane to a widely sepa- rated atresia with a V-shaped mesenteric defect and loss of gut (Fig. 23.13). About 10% of atresias are multiple. Clinical aspects \200 Bile-stained vomiting and abdominal distension. AXR Laparotomy: length of the remaining sma ll bowel. vomiting: babies present shortly after birth with bile-stained \200 shows multiple \202 uid levels (Fig. 23.14). end-to-end anastomosis. The prognosis depends on the Meconium ileus The incidence of MCI is 71/2500 live births. MCI is associated with cystic \201 brosis (CF): 15% of children with CF present with MCI. Lack of pan- creatic enzymes r esults in meconium that is thick and viscous causing an intraluminal obstruction in the ter minal ileum. Occasionally the distended obstructed bowel will perforate or result in volvul us in utero, so-called \200\230complicated \200\231 MCI. Babies present at birth with inte stinal obstruction. Management Treatment of MCI involves relieving the intestinal obstruction. \200 Gastrograf \201 n perforation the obstruction may be relieved by hypertonic contrast, whic h draws \202 uid into the bowel lumen, and the detergent then loosens inspissated meconiu m. Laparotomy Management enema: provided that there is no evidence of intra-uterine \200 . for unsuccessful enema or complicated MCI. of CF if diagnosed. 23_McClure_23.indd 862 11/14/2012 3:30:22 PM MECONIUM ILEUS 863 Dilated stomach Dilated duodenum No gas in bowel distal to atresia Fig. 23.12 Features of duodenal atresia on AXR. Atresias in continuity Atresia with a gap Apple peel atresia Multiple atresias Fig. 23.13 Types of small bowel atresia. Dilated stomach Gas in duodenum and jejunum above atresia No gas in bowel distal to atresia Fig. 23.14 Features of jejunal atresia on AXR. 23_McClure_23.indd 863 11/14/2012 3:30:23 PM CHAPTER 23 Pediatric surgery 864 Acute appendicitis Acute appendicitis is the commonest abdominal emergency in children, aff ecting approximately one-sixth of the population. Acute appendicitis begins with obstructio n of the lumen of the appendix, often by a faeco- lith, and this causes vague central abdom inal pain. After about 6 \200\22312hr an in \202 ammatory process involves the full thickn ess of the wall of the appen- dix. After a further 24 \200\22336hr the appendix will become gangrenous and perforate. Irritation of the peritoneum results in more severe abdominal pa in localized to the right iliac fossa. \200 Pain is aggravated by movement. \200 Child may prefer to lie still with knees \202 exed. \200 Mild fever is usual. \200 Peritone al irritation results in involuntary spasm in the muscles of the abdominal wall \200\224 \200\230guarding \200\231. Diagnosis The mortality from appendicitis is virtually zero. However, substantial morbidity is incurred by delayed diagnosis. The diagnosis of appendicitis is clinical and laboratory investigations are generally not helpful. \200 The \200\230classical \200\231 symptoms and signs of acute appendicitis are seen in about 60% of cases. Of all children admitted to hospital with abdominal pain only about 30% will have acute appendicitis. Not all of these cases are obvious at the initial assessment (prob ably only 50 \200\22370%); if there is any doubt, child should be admitted to hospital for observation. Urinalysis is abnormal in about 1/3 children with acute appendicitis: pyuria a nd even bacteriuria may be present. The temptation to start antibiotics for a presumptive d iagnosis of UTI should be avoided unless there are symptoms of dysuria. The WCC is normal i n 10 \200\22320% of children with appendicitis. if there is clinical doubt, US is the inves tigation of choice. The US: overall accuracy of US in the diagnosis of acute appendicitis i s around 90%. \200 23_McClure_23.indd 864 11/14/2012 3:30:23 PM MESENTERIC ADENITIS 865 Mesenteric adenitis Mesenteric adentitis (MeA) is a condition that mimics acute appendiciti s. It is usually the result of an intercurrent viral infection. Children with MeA typically present with: \200 \200 \200 fever; malaise; central abdominal pain. Diagnosis \200 Usually a period of observation is necessary during which time the symptoms remain static o r improve rather than progress as would be expected with appendicitis. MeA accounts for the majority of children who undergo a normal appendicectomy. After surgery the post-operative course is usually uneventful. Meckel \200\231s diverticulum Meckel \200\231s diverticulm (MD) is: \200 A persistence of the embryonic vitelline duct that normally involutes during late fetal dev elopment. Present in 2% of the population and the majority are asymptomatic. A cause of GI bleeding, obstruction, in \202 ammation, and umbilical discharge. \200 Management \200 Rectal bleeding from a MD is painless, fresh, and suf \201 cient to cause a drop in hemogl obin. Sometimes a 99mTc-pertechnetate isotope scan will identify a MD. Laparotomy: even if the scan is \200\223ve. Diverticulitis or perforation of a MD is clinically indistinguisha ble from appendicitis. Symptomatic MD should be resected. persistent or recurrent bleeding requires a laparotomy 23_McClure_23.indd 865 11/14/2012 3:30:23 PM CHAPTER 23 Pediatric surgery 866 Gastroschisis The incidence of gastroschisis is 1/3000 live births, but it is increasing. M ost fetuses with gastroschisis are identi \201 ed on prenatal US and delivery can then be arranged in a regional neonatal surgical center. The abnormality is immediately apparent at birth as a defect in the abdominal wall to the right of the umbilicus (Fig. 23.15). The bo wel is eviscerated and not covered by a sac. As a result of contact with amniotic \202 ui d the bowel is thickened and matted. Associated malformations are uncommon except intestina l atresias (10%). Management \200 \200 \200 \200 Immediate: cover the exposed bowel with Cling \201 lm \204 . Keep the baby warm and hydrat ed. AXR is unnecessary. Surgery: Often this has to be staged using a silo because the abdom en is too small to accommodate the intestine. The silo is reduced serially over a period of 1 \200\2232wks and then s closure of the defect is performed. Nutrition: because intestina l function is slow to resume after the abdominal wall is closed. However, the long-term out come is excellent. the defect requires surgical closure as rapidly as possible. total parenteral nutrition may be required for many weeks Exomphalos (omphalocele) The incidence of exomphalos is 1/3000 live births (see Fig. 23.15) . It is usu- ally identi \201 ed on prenatal US. It is characterized by: \200 Hernia into the base of the umbilical cord \200\224the herniated bowel is covered by a sac (amnion). Exomphalos major: Exomphalos minor: \200 defect >5cm diameter. defect <5cm diameter. Malformations in association with exomphalos are found in 50% of cases: \200 \200 \200 trisomies 18, 13, 21 and Turner \200\231s syndrome. Chromosomal defects: Cardiac defects. BWS. Syndromes: Surgical treatment \200 \200 Closure of the defect in one or more stages. The prognosis depends on associated malformati ons. 23_McClure_23.indd 866 11/14/2012 3:30:23 PM EXOMPHALOS (OMPHALOCELE) 867 Exomphalos Gastroschisis Matted loops of bowel with no covering Bowel covered by sac of amnion Defect to the right of the umbilicus Fig. 23.15 Anterior abdominal wall defects. 23_McClure_23.indd 867 11/14/2012 3:30:23 PM CHAPTER 23 Pediatric surgery 868 Inguinal hernias Groin hernias in children are almost invariably indirect inguinal hernias. Femoral hernias are rare in children. Inguinal hernias have the following characteristics. \200 \200 \200 \200 More common in boys. More common on the right side, due to later descent of right testis. 1 5% hernias are bilateral. Symptoms are rare. Clinical care \200 A reducible swelling in the groin, often extending into the scrotum (Fig. 23.16). Surgical herniotomy. Infants should be repaired within a few weeks of diagnosis because the risk of incarceration is high. The risk of incarceration lessens after the age of 1yr. Incarcerated hernia \200 \200 Incarceration results in an intestinal obstruction. There is a 30% risk of testicular infar ction due to pressure on the gonadal vessels. Treatment of an irreducible inguinal hernia c omprises resuscitation of the child and then reduction of the hernia by taxis (i.e. gentle, but sustained pressure is applied to the sac to reduce the contents). Most hernias can be reduced safely, although it may be necessary to give the baby morphine \201 rst. If the h ernia cannot be reduced, emergency surgical exploration is necessary (but this is rare). Th e use of gallows traction to reduce a hernia is obsolete. Provided the hernia is reduced a herniotomy should be performed after 24 \200\22348hr to allow for any oedema to settle. Hydroceles Infantile hydroceles are common. \200 Caused by failure of the processus vaginalis to obliterate after testicular descent through the inguinal canal. Clinical signs are a soft swelling around the testis that transillumin ates and above which the examiner can get (Fig. 23.16). Most resolve by the second year and those that do not should be treated surgically through a short groin incision. Check for i nguinal hernia. 23_McClure_23.indd 868 11/14/2012 3:30:24 PM HYDROCELES 869 Inguinal hernia (common, reducible, can \200\231t get above it) Encysted hydrocele (rare, will not reduce, separate from testis) Hydrocele (very common, can get above it, irreducible, transilluminates) Superficial inguinal lymph nodes (usually small and multiple) Fig. 23.16 Groin swellings. 23_McClure_23.indd 869 11/14/2012 3:30:24 PM CHAPTER 23 Pediatric surgery 870 Hirschsprung \200\231s disease The incidence of HSD is 1/5000 live births. It may be famili al and associated with trisomy 21. \200 \200 It is caused by a failure of ganglion cells to migrate into the hindgut. This defect leads to an absence of co-ordinated bowel peristalsis and functional intestinal obstruction at th e junction ( \200\230transition zone \200\231) between normal bowel and the distal aganglio nic bowel. In 80% of cases the transition zone is in the rectum or sigmoid \200\224short se gment disease. In 20% of cases the entire colon is involved \200\224long segment disease. O ccasionally, children with short segment disease present in childhood with chronic constipa tion. \200 Diagnosis \200 Usually presents within the \201 rst few days of life with low intestinal obstruction, i. e. failure to pass meconium, abdominal distension, and bile-stained vomiting. 99% of normal newborns pass meconium within 24hr of delivery. AXR: Rectal biopsy: \200 distal intestinal obstruction. no ganglion cells in the submucosa. Surgical treatment Many surgeons now perform a single stage pull-through in the neonatal pe riod, managing initial intestinal obstruction with rectal washouts, but traditionally a 3-s tage procedure is used. \200 Defunctioning colostomy, with multiple biopsies to con \201 rm the site of the transition zone. Pull-through procedure to bring ganglionic bowel down to the anus. Closure of colosto my. \200 Outcome \200 The long-term results are generally satisfactory with approximately 75% of children acquiri ng normal bowel control, 15 \200\22320% partial control, and 5% who never gain control and may end up with a permanent stoma. Most important complication of HSD is enterocolitis. A d ramatic gastroenteritic illness characterized by abdominal distension, bloody watery diarrh ea, circulatory collapse, and septicaemia. Condition usually associated with Clostridium di f \201 cile toxin in the stools. Mortality 710%. 23_McClure_23.indd 870 11/14/2012 3:30:24 PM RECTAL PROLAPSE 871 Rectal prolapse Rectal prolapse refers to a mucosal or full-thickness herniation of rectum through the anal canal. \200 \200 Most commonly seen in constipated toddlers squatting and straining. Rarely associated with diarrhea, cystic \201 brosis, and coeliac disease. Management \200 Often the prolapse reduces spontaneously after defecation. If not, gentle digital reduction should be performed. Constipation should be treated. Recurrent prolapse may be managed wit h submucous injection of 5% phenol in almond oil. More complicated surgical procedures are rarely necessary. \200 23_McClure_23.indd 871 11/14/2012 3:30:24 PM CHAPTER 23 Pediatric surgery 872 Anorectal malformations The incidence of anorectal malformation is 1/5000 live births. Anor ectal malformations comprise part of the VACTERL association (see b p.848). The abnormality should be identi \201 ed at birth. The baby presents with: \200 \200 \200 failure to pass meconium; abdominal distension; bile-stained vomiting. Anatomy The precise anatomy varies but the malformation can be subdivided into high and low /intermediate anomalies in males and females. Low/intermediate anomalies \200 \200 Rectum is present and passes through a normal sphincter complex. In boys (Fig. 23.17) there is a tiny \201 stulous track to the surface of the perineum, often anteriorly on to the scrotum. If meconium is visible on the perineum a local \200\230cut-back \200\231 procedur e can be performed to open the \201 stula back to the rectum in anticipation of normal co ntinence. In girls (Fig. 23.18) the rectum usually opens into the back of the introitus as a rectovestibular \201 stula. This abnormality is termed intermediate because, although n ormal continence is to be expected, reconstruction involves division of a common wall betwe en rectum and vagina. For this reason treatment involves a 3-stage procedure with defunctio ning colostomy, anorectal reconstruction, and then closure of the stoma. Vesicoureteric re \202 ux is very common. High anomalies \200 \200 These anomalies are rare in girls but common in boys (Fig. 23.17). The sphincter complex is poorly developed and the prospects for continence are mediocre. In boys the rectum makes a \201 stulous connection with the urethra. Treatment involves a defunctioning colostomy w ithin the \201 rst 48hr of birth, reconstruction at a few months of age (most commonly in volving a posterior sagittal anorectoplasty performed through a midline perineal incision), and then closure of the colostomy. 23_McClure_23.indd 872 11/14/2012 3:30:24 PM ANORECTAL MALFORMATIONS 873 Low anomaly \200\223perineal fistula High anomaly \200\223recto-urethral fistula Recto-urethral fistula lies above the levator ani which is deficient Rectum passes through the levator ani sphincter Recto-urethral fistula Site of anus Fistula from rectum onto perineum Site of anus Fig. 23.17 Male anorectal malformations. Intermediate anomaly \200\223recto-vestibular fistula Low anomaly \200\223perineal fistula Rectum passes through a normal levator ani complex Rectum passes through a normal levator ani complex Stenotic anterior perineal opening Site of anus Site of anus This anomaly is termed \200\230intermediate \200\231 because of the common wa ll between the rectum and the vagina, which makes reconstruction complex Rectum opens into posterior fourchette of the introitus Fig. 23.18 Female anorectal malformations. 23_McClure_23.indd 873 11/14/2012 3:30:24 PM CHAPTER 23 Pediatric surgery 874 Umbilical anomalies Granuloma The commonest umbilical abnormality seen in infants is an umb ilical granu- loma (see Fig. 23.19). This is a harmless reaction to the resolving umbilical stump and usually disappears by the 2nd to 3rd week. Treatment A persistent granuloma should be cauterized with a silver nitrate stick. Vaseline should be applied round the umbilicus to prevent damage to the surrounding skin and a smal l dressing placed over the umbilicus to prevent marking of the baby \200\231s vest. Multipl e applications may be necessary. (cid:1) Caution A persistent \200\230granuloma \200\231 discharging small bowel contents s igni \201 es a patent vitello-intestinal duct (Fig. 23.19). Treatment involves surgical ex ploration of the umbilicus and excision of the duct with a small segment of ileum. The diag nosis is clinical. Urachal remnants These are uncommon anomalies that present in infancy or early child- hood. The urachus is an embryonic tubular connection between the blad- der and the allantois tha t normally obliterates before birth. \200 \200 Main Bladder excluded by micturating cystography. Treatment is surgical closure. symptom: persistent discharge of urine from the umbilicus. outlet obstruction (posterior ur ethral valves) should be Umbilical hernias (Fig. 23.19) \200 \200 Common, particularly in Afro-Caribbean children. Most will close spontaneously during the \201 rst few years of life, regardless of size. Complications are rare. If the hernia fail s to close surgical repair can be performed at around 5yrs of age. \200 23_McClure_23.indd 874 11/14/2012 3:30:25 PM UMBILICAL ANOMALIES 875 Typical umbilical hernia (large, easily reducible protrusion into umbilical skin) Vitello-intestinal fistula visible as intestinal mucosa in the umbilical stump Cord clamp Umbilical granuloma Fig. 23.19 Disorders of the umbilicus. 23_McClure_23.indd 875 11/14/2012 3:30:25 PM CHAPTER 23 Pediatric surgery 876 Testicular torsion Testicular torsion must be excluded in a child with acute scrotal pain. The peak incidence occurs around 12yrs, but it can occur at any age. \200 Congenital has a hard, painless scrotal mass. Testis has invariably infarcted and explorati on is not necessary, nor is \201 xation of the opposite testis. The pathology is torsion of the spermatic cord outside the tunica vaginalis. Torsion outside the perinatal period: t he result of an abnormally mobile mesentery of the testis inside the tunica vaginalis. This anomaly is bilateral and allows the gonad to twist on its vascular pedicle. testicular torsion: rare perinatal event. Newborn infant Presentation \200 Sudden onset severe scrotal pain, often associated with nausea and vomiting. Tender testis. Overlying scrotal skin may be reddened and oedematous. \200 Treatment \200 Immediate scrotal exploration is mandatory to salvage the testis, which should then be \201 xed to prevent recurrence. The contralateral testis should also be \201 xed. Differential diagnosis of acute scrotal pain See also b p.877 Testicular torsion \200 \200 \200 Sudden onset pain, swelling, and nausea Testis is very tender, and may lie transversely in scrotum Scrotal skin may be red Torted hydatid \200 \200 \200 Gradual onset of less severe pain; no nausea Focal tenderness at upper pole of testis Torte d hydatid may be visible through scrotal skin as a pea-sized blue/black swelling Epididymo-orchitis \200 \200 \200 Insidious onset of dysuria and fever Usually associated with a urinary tract infection Red tender scrotum Testicular trauma History obvious and there are signs of trauma/ haematocele Idiopathic scrotal oedema \200 \200 \200 Child is well Scrotal skin is cellulitic but the testes are not tender The condition settle s spontaneously within a few days 23_McClure_23.indd 876 11/14/2012 3:30:25 PM ORCHITIS AND EPIDIDYMITIS 877 Orchitis and epididymitis Orchitis \200 Orchitis is an uncommon condition in boys that presents with fever and testicular pain. App roximately 20% of prepubertal patients with mumps develop orchitis (see b p.713). Diagnosis based on a history of recent mumps or parotitis; mumps orchitis is unilateral in 70% of ca ses. In 30% of cases, contralateral testicular involvement follows a few days later. This c ondition is rare in post-pubertal boys. Bacterial orchitis is usually associated with an ep ididymitis. \200 Epididymitis \200 \200 Usually associated with concomitant orchitis. In children epididymo-orchitis is usually ass ociated with a urinary tract infection: infected urine re \202 uxes down the vas. Structur al abnormality in the renal tract should be excluded. Epididymo-orchitis presents with feve r, urinary symptoms, and scrotal pain. In sexually-active adolescents epididymo-orchitis ma y be caused by gonorrhea or Chlamydia. Epididymo-orchitis should be managed with antibiotic s once urine has been sent for culture. Adolescents should be screened for sexually transmi tted infection (see b p.801). \200 