Pediatric Small-Bowel Obstruction
- Author: Jaime Shalkow, MD; Chief Editor: Carmen Cuffari, MD more...
Background
Many different pathologic processes can cause pediatric small-bowel obstructions. These processes can be divided into acute intestinal obstructions and chronic, partial intestinal obstructions. These conditions can be further subdivided into those that present in the immediate postnatal period and those that occur later in childhood (see the images below). (See Etiology, Presentation, and Workup.)
Small-bowel obstruction visible on plain radiograph caused by intussusception in a 5-month-old patient.
Surgical photograph of a transition zone in an infant with small bowel obstruction. Intestinal obstruction occurs in about 1 in 1,500 live births. Intestinal obstruction should be suspected in any child with persistent vomiting, distention, and abdominal pain, because delayed diagnosis and treatment can lead to devastating consequences. Infants and young children with intestinal obstruction present with pain, irritability, vomiting, and abdominal distention. Small-bowel obstructions progress to decreased or no bowel movements. Undiagnosed or improperly managed obstructions can progress to vascular compromise, which causes bowel ischemia, necrosis, perforation, sepsis, and death. (See Prognosis, Presentation, and Workup.)
Congenital obstructive lesions of the intestines can be viewed as intrinsic (atresia, stenosis, meconium ileus, aganglionic megacolon) or extrinsic (malrotation, constricting bands, intra-abdominal hernias, duplications). An attempt should be made to locate the lesion preoperatively to guide the surgical approach. (See Workup and Treatment.)
When the obstruction is complete, there should be little difficulty in clinical recognition, but when it is incomplete or intermittent, the diagnosis may pose considerable difficulty. Polyhydramnios frequently accompanies high intestinal obstruction. When polyhydramnios has been noted, the infant's stomach should be aspirated immediately after birth. Aspiration of 15-20mL or more of gastric fluid, especially if it is bile stained, is suggestive of a high intestinal obstruction.[1] (See P resentation and Workup.)
Patient education
For patient education information, see the Digestive Disorders Center, as well as Abdominal Pain in Children, Hernia, Vomiting and Nausea, Constipation in Children, and Colic.
Pathophysiology
The normal bowel contains gas and chyle, which is the sum of food and salivary, gastric, biliary, pancreatic, and intestinal secretions. Chyle continues to accumulate even without oral intake. Intrinsic or extrinsic blockage of the small bowel leads to accumulating secretions that dilate the intestine proximal to the obstruction.
Increased peristaltic contractions and intraluminal pressure may cause frequent loose stools and flatus early in the disease course. Vomiting is also an important sign of obstructed children, and its characteristics can suggest the level of the obstruction. Intestinal absorption and lymphatic drainage decrease if intraluminal pressure exceeds capillary and venous pressure in the bowel wall.
The bowel becomes ischemic when capillary blood flow stops, allowing bacteria to pass into the peritoneum; from that point, it passes into the bloodstream, leading to septicemia by a process known as bacterial translocation. Peritoneal fluid is constantly secreted by the visceral peritoneum and absorbed by the parietal peritoneum, mostly in the diaphragmatic abdominal surface, where the diaphragmatic pores can be distended as much as 3 times their normal size to allow the passage of bacteria.
The colonized fluid is then transported via the lymphatic channels into the thoracic duct, which drains in the jugulosubclavian angle of Pirogoff, allowing bacteria to enter the circulation and causing septicemia. Bacteria injected into the peritoneum can be cultivated from peripheral blood only 6 minutes after the injection, confirming the extremely rapid flow from the peritoneum into the systemic circulation.
Perforation can develop as the ischemia leads to bowel necrosis. First, lymphatic obstruction occurs because of the lesser pressure in these vessels. This is followed by venous obstruction, which accelerates the edema process because blood enters the affected bowel segment but does not have a drainage route. Finally, the continuous increase in the bowel wall pressure blocks the arterial vessels, leading to ischemic necrosis and perforation. Massive third spacing of fluids rapidly leads to shock, contributing to morbidity and mortality. This sequence may occur more rapidly in a closed-loop obstruction with no proximal escape for bowel contents.
Etiology
Intussusceptions
Intussusception is the most common cause of intestinal obstruction in infants and children aged 3 months to 6 years and is the second most common cause of acute abdomen in this age group. It occurs when a proximal segment of the intestine (called the intussusceptum) telescopes or invaginates into the lumen of another, immediately adjacent distal segment (called the intussuscipiens). Most intussusceptions are idiopathic. A lead point is identified in only 2-8% of cases. (See the image below.)
Small-bowel obstruction visible on plain radiograph caused by intussusception in a 5-month-old patient. Although the cause of intussusception is unknown in 90-95% of children, a viral etiology is suspected because of intussusception’s seasonal predisposition for spring and autumn, as well as a higher incidence of adenoid hypertrophy in children who suffer intussusceptions.
Gastroenteritis, rotavirus infection, or allergic stimuli are believed to cause intestinal lymphoid tissue to swell and become a lead point to pull the mass into the adjacent proximal intestine. In patients younger than 1 month and older than 3 years, pathologic lesions serve as the lead points that produce the condition.
An analysis by Okimoto et al of 71 stool samples from pediatric patients with intussusception indicated that adenovirus is also a risk factor for the development of intussusception, with the risk being particularly high in children over age 2 years.[2]
Intussusception is a well-described complication of patients with Meckel diverticulum,[3] Waugh syndrome, cocaine abuse, laxative use, and even antibiotic use, presumably due to motility derangements caused by some of these agents. In Henoch-Schönlein purpura, mucosal hematomas are thought to act as lead points.[4]
Peutz-Jeghers syndrome is a rare cause of intussusception in older children; in this condition, hamartomatous polyps act as the lead point. Similarly, familial polyposis coli and juvenile polyposis can also cause intussusceptions, and a vermiform appendix may occasionally cause the disease. Familial cases of intussusception have been described. Suspect intestinal lymphomas in all children older than 6 years with intussusception.
Extensive retroperitoneal dissections are known to predispose children to postoperative intussusceptions, probably because of intestinal dysmotility in these patients. Blunt abdominal trauma has also been known to cause intussusception.
Intussusceptions are believed to begin with an intestinal spasm around a lead point; the bowel relaxes just distally to this spasm, which allows the longitudinal muscle fibers to draw the contracted portion of bowel into the relaxed portion.
In some patients, recognizable lead points are found, such as Meckel diverticulum, intestinal polyps, duplications, lymphosarcomas, and, rarely, foreign bodies. Compression of the mesentery at the point of invagination occurs from the start, leading to immediate venous compression, venous stasis, and edema. Goblet cells pour copious amounts of mucus into the intestinal lumen. The engorged hyperemic intestinal mucosa seeps blood, which mixes with the mucus to form the currant jelly stool that occurs in 60% of patients. Tissue pressure eventually exceeds arterial pressure, and necrosis ensues within 24 hours.
The peak age of presentation is between the ages of 5 and 10 months. Intussusception is more common in males. Less than 1% of intussusceptions are found in neonates; however, cases have been reported in newborns and premature babies. Early diagnosis and prompt treatment prevent catastrophic complications. In 95% of cases, the intussusception is in the ileocecal area. Ileoileal and colocolic intussusceptions are rare.
Occasionally, an ileoileal intussusception of the terminal ileum may progress through the ileocecal valve, a condition known as ileoileocolic intussusception. Ileoileal intussusceptions are seen as a postoperative complication after extensive retroperitoneal dissections, as in surgery for neuroblastoma or Wilms tumors.
Management includes radiographic reductions with air enema and, if necessary, open reduction with bowel resection. Reports have concluded that laparoscopy is a reasonable alternative to pediatric intussusception, even in the event of requiring a bowel resection.[5]
Incarcerated hernias
The overall incidence of inguinal hernias in childhood ranges from 0.8-4.4%. The incidence is up to 10 times higher in boys than in girls. The incidence is much higher in premature infants; inguinal hernias develop in 13% of infants born before 32 weeks' gestation and in 30% of infants weighing less than 1000g. (See the images below.)
Small-bowel obstruction caused by an incarcerated inguinal hernia in a 2-month-old infant with bilateral inguinal hernias as well as an umbilical hernia.
Incarcerated left inguinal hernia. During the third month of gestation, the abdominal peritoneum protrudes at the internal inguinal ring and extends to the scrotum to form a diverticulum known as the processus vaginalis. In females, this diverticulum is called the canal of Nuck and extends through the internal inguinal ring to the labia majora.
At birth, the processus vaginalis is open and in communication with the peritoneal cavity in about 80% of babies. Closure takes place progressively during the first 2 years of life, with an estimated 20-30% incidence of patency at age 2 years and then little further decline. This patent processus vaginalis becomes a hernia only when it contains abdominal viscera.
Incarcerated hernias occur when the contents of a hernia sac cannot be reduced back into the abdominal cavity. Incarcerated or nonreducible hernias may contain small bowel, cecal appendix (Amyand hernia), omentum, or, rarely, Meckel diverticulum (Littre hernia). In girls, the ovary and/or fallopian tube are usually incarcerated. When a part of the bladder wall or the colonic wall is contained in the hernia sac, it is called a sliding hernia.
Umbilical hernias are the result of an incompletely closed umbilical ring. Most spontaneously resolve by age 2 years (80%).
The risk of incarceration in premature infants is increased, being as high as 31% in some series.[6] Incarcerated hernias can be inguinal, femoral, or umbilical. Inguinal and femoral incarcerated hernias are most common in both sexes.
Femoral hernias, which tend to incarcerate, are extremely rare in children and are the only hernias that occur in girls more often than in boys. Femoral hernias often present as recurrent hernias after inguinal hernia repair, most likely because the surgeon was misled by the findings of a processus vaginalis at the initial surgery and missed the actual hernia defect. These are uncommon in infants.[7]
Incarceration represents the most common complication associated with inguinal hernias. In several large series, incarceration was reported in 6-18% of patients. The incidence could be as high as 30% for infants younger than age 2 months. Most inguinal hernias in children are indirect hernias. Most direct hernias in the pediatric population occur following repair of an indirect hernia.
Umbilical hernias are very common in children, rarely incarcerate, and often close spontaneously by age 5 years.
Unless there is clear peritonitis or bowel compromise, incarcerated inguinal hernias can usually be reduced manually using a taxis technique. Up to 80% of incarcerated hernias can be reduced this way.[8]
In girls, an incarcerated ovary may be present in the hernial sac, in which case, vascular compromise risk is high (33%).[9]
Internal hernias are extremely rare and cause bowel obstruction in children. Hernias in the mesentery, mesocolon, mesosigmoid, and Winslow foramen[10] and defects in the falciform ligament have been described.[11]
Malrotation of bowel with midgut volvulus
The reported incidence of malrotation is 1 in every 500 infants. It can be isolated or associated with other malformations, including congenital diaphragmatic hernia, abdominal wall defects, intestinal atresias, and Beckwith-Wiedemann syndrome.[12]
Intestinal malrotation refers to errors of midgut rotation around the superior mesenteric artery axis and the subsequent fixation of the midgut in the peritoneal cavity. Nonrotation, incomplete rotation, reversed rotation, and alterations of fixation (including the internal hernias [mesocolic, paraduodenal] and the mobile cecum) are among the many embryonic variants of the anomaly. (See the images below.)
Upper GI contrast study showing a malrotation with lack of normal C-shaped duodenum and the small bowel "hanging" on the right side of the abdomen.
Contrast enema with an abnormally located cecum in a patient with malrotation. The primitive gut, which forms during the fourth week of embryonal life, is divided into the foregut, midgut, and hindgut. The largest of these, the midgut, is the only portion that undergoes rotation by herniating extraembryonically into the umbilical cord and rotating 270° in a counterclockwise direction around the superior mesenteric artery on its journey back to the abdominal cavity by 11 weeks' gestation. This produces the normal C-shaped configuration of the duodenum and results in the cecum coming to rest in the right lower quadrant of the abdomen.
For unknown reasons, midgut rotation can arrest at any point, most commonly rotating 180° and leaving the cecocolic loop in the right upper quadrant. Dense peritoneal bands (ie, Ladd bands) cross from the malpositioned right colon across the duodenum to the right lateral abdominal wall. This configuration leaves a narrow mesenteric root and creates a predisposition to clockwise torsion of the midgut, while the Ladd bands themselves can obstruct the duodenum.
Theories of malrotation are based on anatomic and pathologic findings, but the actual rotation movements have not been seen in human embryos. Evidence suggests that, at least in rats, the midgut never rotates around the superior mesenteric artery and that the final normal position and fixation of the midgut are probably due to differential growth of specific intestinal segments rather than to rotational movements.
Malrotation is always present in patients with abdominal wall defects (gastroschisis, omphalocele) and in patients with congenital diaphragmatic hernia. It is often associated with other congenital and acquired lesions of the gastrointestinal (GI) tract, such as Hirschsprung disease, intussusception, and atresia of the jejunum, duodenum, and esophagus.
In children, the most common form of malrotation occurs when the process of rotation is incomplete and the ligament of Treitz or the cecum is abnormally located or fixed. The mesenteric attachment of the midgut to the posterior abdominal wall is narrow and predisposes the midgut to twist around an axis formed by the superior mesenteric artery (midgut volvulus). Complete volvulus of the bowel for more than 1-2 hours can totally obstruct blood supply to the bowel, leading to complete necrosis of the involved segment. (See the image below.)
Surgical photograph of necrotic bowel in a patient with midgut volvulus. Postoperative adhesions
Adhesive small-bowel obstruction is a surgical complication, with postoperative adhesions being responsible for about 7% of the intestinal obstructions in infants and children. A single adhesion causes most obstructions, regardless of the nature of the previous illness or type of abdominal surgery. The postsurgical onset of obstructive symptoms can take from 2 days to 10 years to occur, although most adhesions (>50%) occur within the first 3-6 postoperative months; few occur after 2 years. The incidence of adhesive small-bowel obstructions seems to be lower after laparoscopic procedures than after laparotomy.[13]
Annular pancreas
Annular pancreas is a rare congenital anomaly seen in 1-3 of every 20,000 autopsies performed. Annular pancreas occurs when the ventral pancreatic bud fails to rotate behind the duodenum, leaving pancreatic tissue fully encircling the second portion of the duodenum. This results in a nondistensible ring of pancreatic parenchyma and a functional stenosis.
In children born with the condition, the second portion of the duodenum is either partially or completely surrounded by pancreatic tissue. Most cases of annular pancreas are diagnosed early in life when patients present with symptoms of duodenal obstruction.[14]
Annular pancreas involves a lesion that consists of a thin, flat ring of histologically normal pancreatic tissue that surrounds the descending duodenum in an anomalous position. Annular pancreas results from abnormal rotation of the ventral pancreatic bud, and usually functions normally, barring development of pancreatitis or an obstruction of the duct of Wirsung.
An annular pancreas can be asymptomatic or can cause external compression on the second portion of the duodenum, which creates a partial or complete obstruction. Annular pancreas is almost invariably associated with an intrinsic cause of duodenal obstruction (duodenal atresia).
Mesocolic hernia
Mesocolic hernia is a rotation abnormality.[15] Nonfixed colonic and duodenal mesenteries lead to formation of potential hernia pouches, which transiently and recurrently entrap the bowel and cause partial obstructions. The exact incidence of mesocolic hernia is not known, because most cases are asymptomatic. (See the image below.)
Mesocolic hernia. The median age at presentation in one series was 13 years, with an age range of 6-19 years. The most common presenting symptom was diffuse abdominal pain lasting 1 day.[16]
The internal hernias may be right sided or left sided and can sometimes incarcerate and strangulate. Mesocolic hernias can also occur when a mesenteric defect is not properly closed during retroperitoneal surgery.
Necrotizing enterocolitis
Necrotizing enterocolitis (NEC) can produce strictures that subsequently cause intestinal obstruction. The most common sites for these strictures are the terminal ileum and the colon. Strictures usually occur within 1-6 months following an acute NEC episode. In patients with NEC, whether a systemic inflammatory response triggered by a perinatal physiologic stress results in intestinal ischemia, bacterial overgrowth, breakdown of the mucosal barrier, and bacterial translocation is unclear.
Strictures from NEC occur most often in premature infants. These strictures account for 15% of deaths in infants older than 1 week whose birth weights were less than 1500 g. However, although prematurity and the associated immaturity of the gut mucosa account for 90% of cases, 10% of NEC occurs in term infants.[17]
Intestinal strictures occur in patients with NEC regardless of management. Retrospective and prospective studies have reported an incidence of strictures of between 10% and 35% for medically and surgically managed patients.
While the exact cause of NEC remains unknown, multiple factors probably lead to ischemic or hypoxemic insult of the intestinal mucosa, followed by bacterial invasion of the denuded mucosa with gram-negative septicemia and intestinal necrosis.
NEC can be regarded as an immunoinflammatory response by the immature and inexperienced gut to environmental antigens such as enteral nutrition and the presence of commensal bacteria. The primary infectious process likely results in enteroinvasion, release of inflammatory mediators, toxin production, ileus, gas production, bowel distention, increased intraluminal pressure, and vascular compromise, which causes loss of mucosal integrity, and bacterial translocation, which results in a systemic inflammatory response.
The most prominent is risk factor prematurity with aggressive hypertonic enteral feedings; however, NEC is seen in 15% of patients that have never been fed. Full-term newborns with polycythemia or congenital heart disease have higher risk for NEC, as do infants who had umbilical arterial or venous catheters in situ. Other risk factors include hypertonic feeding solutions that damage the mucosal epithelium of the intestine and episodes of apnea with ischemia of the GI tract.
Mortality rates from NEC are high, ranging from 15-30%. There is strong evidence that half of the survivors have neurodevelopmental outcomes lower than their peers without NEC.[18]
Causes of chronic, partial intestinal obstructions
Most chronic, partial intestinal obstructions are due to anatomic abnormalities such as intestinal duplications, hernias, and intestinal stenosis. Rarely, children may experience obstruction due to trichobezoar; this usually occurs in young females with trichotillomania (an irresistible desire to pull out one's own hair) or trichophagia (in which an individual eats hair or wool). When the trichobezoar has a long tail that extends beyond the stomach into the small intestine, it is called Rapunzel syndrome.
Cecal volvulus
Cecal volvulus is a rare disorder of nonfixation (ie, a mobile cecum), rather than a complete malrotation. Cecal volvulus most commonly occurs as axial twisting of the cecum, ascending colon, and terminal ileum. It has also been described in patients who have undergone a Malone antegrade continence enema (MACE) procedure, in which the cecal appendix is used as a tubular conduit between the abdominal wall and the cecum, creating a stoma through which the patient can get an antegrade enema to achieve "social continence."[19]
Duplication cysts
Duplications of the alimentary tract make up a group of rare malformations that vary greatly in appearance, size, location, and symptoms. Intestinal duplications can be either cystic or tubular in shape. They have been reported to occur anywhere along the GI tract, from the tongue to the anus, although most are located in the terminal ileum near the ileocecal valve. Duplications are seen in 1 of every 4500 autopsies; 85% of cases are detected by age 2 years.[20]
The embryogenesis of rectal duplications has been attributed to the pinching off of diverticula that are present in the 8-week-old to 9-week-old embryo. The reported association of spinal abnormalities makes the split notochord mechanism another probable origin of rectal duplications.
The 3 characteristics of alimentary tract duplications, as proposed by Ladd and Gross, include (1) contiguity with and strong adherence to some part of the alimentary tract, (2) a smooth muscle coat (usually in 2 layers), and (3) a mucosal lining that consists of 1 or more types of cells normally observed in the alimentary tract.[21]
Most duplications are truly enteric cysts; few of them actually represent attempts to double the alimentary tract. The intestinal epithelium may or may not correspond to the epithelium of the adjacent intestinal structure. Gastric mucosa is the most common ectopic tissue found.
Intestinal obstruction, bleeding, infection, and carcinomatous degeneration have been observed with these anomalies, and early correct diagnosis is vital. Most symptoms are caused by the mass effect, and the duplication causes either a partial or complete small-bowel obstruction.
Causes of immediate postnatal small-bowel obstructions
Most of these obstructions are the result of jejunoileal atresia (see the images below), meconium ileus, or extrinsic or intrinsic duodenal obstructions. Jejunoileal atresia (ie, complete obstruction) and stenosis (ie, incomplete obstruction) are extremely important causes of neonatal intestinal obstruction. Atresia, which accounts for 95% of cases, is a congenital obstruction secondary to complete occlusion of the intestinal lumen. In about 25% of these patients, atresia is associated with major GI anomalies (eg, malrotation, meconium ileus, volvulus, omphaloceles, gastroschisis).
Upper GI contrast study demonstrating a jejunal atresia with a proximal dilated atretic bowel and lack of passage of contrast into the distal small bowel.
Surgical photograph of the patient in the previous image depicting the proximal dilated atretic jejunum. Stenosis is the cause of the remaining 5% of cases. It is a partial congenital obstruction caused by incomplete intraluminal occlusion. Both entities appear to be caused by incomplete vacuolization of the embryonic intestine during the cord phase of intestinal development. Patients with intestinal atresia are epidemiologically characterized by low gestational age and low birth weight.
Meconium ileus
Meconium ileus occurs almost exclusively in patients with cystic fibrosis (CF) and is usually the earliest clinical manifestation: 10-15% of patients with CF have meconium ileus, and 90% of patients with meconium ileus have CF.
Meconium ileus is caused by hyperviscous secretions produced by the small intestine’s mucous glands. Meconium ileus is the most severe clinical expression of exocrine pancreatic insufficiency; the lack of normal pancreatic exocrine secretions is the most important factor in the formation of the thick meconium. These secretions cause a thick and tarlike in utero meconium that has a low water content. This abnormally sticky meconium adheres firmly to the small intestinal mucosa and produces intraluminal obstructions. The involved bowel segment may dilate and may even perforate or develop a volvulus.
Meconium plug syndrome or meconium obstruction does not appear to be associated with CF or Hirschsprung disease in extremely low birth weight infants.
Duodenal obstructions
Duodenal obstructions in newborns may be partial or complete and they may be secondary to extrinsic or intrinsic abnormalities. Duodenal atresia and stenosis are believed to be caused by failure of recanalization or vacuolization of the duodenum after the embryologic cord stage, when the lumen is completely obliterated. Duodenal atresia completely obliterates the duodenal lumen; duodenal stenosis only partially or incompletely obstructs the duodenal lumen.
Duodenal atresia and stenosis are relatively rare causes of obstruction, with a frequency of 1 in 20,000-40,000 births. Although duodenal atresia is at least 4 times more common than duodenal stenosis, stenosis occurs more often in the duodenum than in other portions of the GI tract and may remain undetected until adulthood.
Duodenal atresia has a high rate of associated anomalies (50%): trisomy 21 (31%), malrotation (20%), congenital heart disease (30%), esophageal atresia (10%), genitourinary anomalies (11%), and anular pancreas (20%). Polyhydramnios occurs in approximately 40% of patients, and this clinical finding suggests a more proximal intestinal obstruction in the fetus.
The 3 basic morphologic features of duodenal atresias are as follows:
- Type I atresias - Characterized by luminal webs or membranes
- Type II - Characterized by a complete atresia connected by a fibrous cord
- Type III - Characterized by complete atresia, with a mesenteric gap between the affected intestinal segments.
Jejunoileal atresia
Jejunoileal atresia is believed to result from intrauterine mesenteric vascular accidents that cause devascularization. Lack of normal vacuolization is thought to be the cause of all type I atresias, which may occur anywhere. Vascular accidents with different degrees of infarction are then thought to be the cause of other types of atresias, which may include not only intestinal, but also mesenteric, defects.
The extent of atresia and the appearance of the atretic intestinal segment vary according to the timing and degree of the disruption of the mesenteric blood supply.
Small-bowel atresia variably reduces the size of the colon. The volume of intestinal secretions and amniotic fluid that passes through the colon in fetal life determines its size in the newborn. Atresia blocks this fluid flow through the colon, thus limiting colon growth; however, passage of meconium does not rule out intestinal atresia, because the vascular insult that leads to the atresia may occur after the recanalization phase of the intestinal development.
Jejunoileal atresias are twice as common as duodenal atresias and are also more common than colonic atresias. Males and females are equally affected. Usually jejunoileal atresias are single atresias (multiple atresias occur in 6-20%). In order of location and frequency, jejunoileal atresias occur as follows:
- Distal ileum - 36%
- Proximal jejunum - 31%
- Distal jejunum - 20%
- Proximal ileum - 13%
In the case of jejunoileal atresias, the obstruction is mechanical; it is caused by the presence of bile, lanugo, and meconium distal to the atresia. In contrast to duodenal atresia, this occlusion happens after intestinal development has been completed.
Following this occlusion, an ischemic injury develops, caused by 1 of the following:
- Volvulus
- Malrotation
- Intestinal strangulation at the umbilical ring
- Intestinal perforation and/or peritonitis
- Vasoconstrictive drugs such as cocaine, pseudoephedrine, and nicotine
Epidemiology
Occurrence in the United States
Malrotation of the bowel with midgut volvulus occurs at a rate of 1 case per 500 infants. Jejunoileal atresia and stenosis have a combined reported incidence of 1 case per 1500-5000 live births. These conditions are common among patients with maternal polyhydramnios; 38% have jejunal atresia, and 15% have ileal atresia. Overall, the atresia is almost equally divided between the jejunum (51%) and ileum (49%).
Jejunoileal atresia is twice as common as duodenal atresia and is more common than colonic atresia. Duodenal atresia and stenosis, collectively, are relatively rare causes of obstruction that occur at a rate of just 1 case per 10,000 live births. The incidence of alimentary tract duplications is 1 case per 4500 population.
Sex-related demographics
The male-to-female ratio for incarcerated hernias is 8:1. Hernias occur on the right in about 60% of males, on the left in 25%, and bilaterally in 15%. Females have bilateral inguinal hernias more often than do males. Malrotation of the bowel with midgut volvulus can affect either sex. Neither duplication cysts nor jejunoileal atresia and stenosis exhibit a sexual predilection.
Age-related demographics
Intussusception can occur at any time in life, but the idiopathic form is primarily a childhood disease, developing especially during infancy. Peak occurrence is in infants aged 5-10 months; average age is about 7-8 months.
Most patients with inguinal hernias present during the first year of life. Approximately one third are younger than 6 months at the time of surgery.
Most patients with symptomatic malrotation of the bowel with midgut volvulus present in early infancy. Approximately 50% of patients present in the first month of life, and 80% present in the first year of life. Midgut volvulus has reportedly occurred in utero. Fewer patients (ie, 6-20%) present at ages older than 1 year; these patients tend to have a longer course of vague symptoms (eg, intermittent, bilious vomiting; chronic abdominal pain).
Most patients with duplication cysts present in early childhood or infancy, although some may not develop symptoms until much later. Many duplication cysts are diagnosed within the first week of life, 60% are identified during the first 6 months of life, and 85% are identified by age 1 year.
For annular pancreas, the age of onset of obstructive symptoms widely varies; sometimes, these do not develop until adulthood. Many pediatric patients present in the newborn period with complete duodenal obstruction, often after the first feeding.
NEC occurs in 90% of premature infants weighing less than 1500 g; however, 10% of NEC occurrences are in the term infant.
Jejunoileal atresia causes obstruction in the immediate postnatal period. Patients with duodenal stenosis may remain asymptomatic until late childhood or may progress to complete obstruction; symptom onset depends upon the degree of stenosis. Patients with duodenal atresia or annular pancreas present in the first 24 hours of life.
Meconium ileus and meconium plug syndrome present in the first few days of life. A rare entity similar to meconium ileus that presents later in life is called meconium ileus equivalent or distal intestinal obstruction syndrome.
Prognosis
Mortality and morbidity in pediatric small-bowel obstruction depend on the type of lesion that causes the intestinal blockage, whether it is a closed-loop or strangulated obstruction, and the time elapsed before diagnosis and definitive, adequate treatment. Mortality is low with early diagnosis and treatment. If left untreated, strangulated obstructions are always lethal. Mortality rates may reach 65% if more than 75% of the small bowel is necrotic at the time of laparotomy. Strictures and adhesions are late complications of treated obstructions. Too much bowel damage can cause malnutrition due to short-bowel syndrome.[22]
Long-term survival in patients with duodenal atresia or stenosis is approximately 86%. Most of the morbidity and mortality is related to cardiac anomalies. This includes patients with annular pancreas.
Although intussusception-associated infant deaths in the United States have declined substantially since the late 20th century, some of these deaths may have been preventable because they were apparently related to delayed or reduced access to health care.
The survival rate at 1 year is approximately 92% in patients with uncomplicated meconium ileus and 89% in patients with complicated disease.
Intestinal resections have been reported in about 1.4-1.8% of patients with incarcerated inguinal hernias. The incidence of testicular infarction and atrophy ranges from 4-12%; young infants seem to be at higher risk.
Wyllie Robert. Intestinal atresia,stenosis and malrotation. In: Nelson Textbook of Pediatrics. 18. Sounders; 327.
Okimoto S, Hyodo S, Yamamoto M, Nakamura K, Kobayashi M. Association of viral isolates from stool samples with intussusception in children. Int J Infect Dis. Sep 2011;15(9):e641-5. [Medline].
Ruscher KA, Fisher JN, Hughes CD, Neff S, Lerer TJ, Hight DW, et al. National trends in the surgical management of Meckel's diverticulum. J Pediatr Surg. May 2011;46(5):893-6. [Medline].
Vestergaard H, Westergaard T, Wohlfahrt J, et al. Association between intussusception and tonsil disease in childhood. Epidemiology. Jan 2008;19(1):71-4. [Medline].
Fraser JD, Aguayo P, Ho B, Sharp SW, Ostlie DJ, Holcomb GW 3rd. Laparoscopic management of intussusception in pediatric patients. J Laparoendosc Adv Surg Tech A. Aug 2009;19(4):563-5. [Medline].
Rajput A, Gauderer MW, Hack M. Inguinal hernias in very low birth weight infants: incidence and timing of repair. J Pediatr Surg. Oct 1992;27(10):1322-4. [Medline].
Ikossi DG, Shaheen R, Mallory B. Laparoscopic femoral hernia repair using umbilical ligament as plug. J Laparoendosc Adv Surg Tech A. Apr 2005;15(2):197-200. [Medline].
Chan KL, Hui WC, Tam PK. Prospective randomized single-center, single-blind comparison of laparoscopic vs open repair of pediatric inguinal hernia. Surg Endosc. Jul 2005;19(7):927-32. [Medline].
Boley SJ, Cahn D, Lauer T, Weinberg G, Kleinhaus S. The irreducible ovary: a true emergency. J Pediatr Surg. Sep 1991;26(9):1035-8. [Medline].
Mboyo A, Goura E, Massicot R, et al. An exceptional cause of intestinal obstruction in a 2-year-old boy: strangulated hernia of the ileum through Winslow's foramen. J Pediatr Surg. Jan 2008;43(1):e1-3. [Medline].
Gingalewski C, Lalikos J. An unusual cause of small bowel obstruction: herniation through a defect in the falciform ligament. J Pediatr Surg. Feb 2008;43(2):398-400. [Medline].
El-Gohary Y, Alagtal M, Gillick J. Long-term complications following operative intervention for intestinal malrotation: a 10-year review. Pediatr Surg Int. Feb 2010;26(2):203-6. [Medline].
Tsao KJ, St Peter SD, Valusek PA, et al. Adhesive small bowel obstruction after appendectomy in children: comparison between the laparoscopic and open approach. J Pediatr Surg. Jun 2007;42(6):939-42; discussion 942. [Medline].
Ohno Y, Kanematsu T. Annular pancreas causing localized recurrent pancreatitis in a child: report of a case. Surg Today. 2008;38(11):1052-5. [Medline].
Kihne M, Ramanujam TM, Sithasanan N. Mesocolic hernia: a rare cause of intestinal obstruction in childhood. Med J Malaysia. Jun 2006;61(2):251-3. [Medline].
Villalona GA, Diefenbach KA, Touloukian RJ. Congenital and acquired mesocolic hernias presenting with small bowel obstruction in childhood and adolescence. J Pediatr Surg. Feb 2010;45(2):438-42. [Medline].
Henry MC, Moss RL. Neonatal Necrotizing Enterocolitis. Seminars in Pediatric Surgery. May 72008;17:98-109.
Stevenson DK, Kerner JA, Malachowski N. Late morbidity among survivors of necrotizing enterocolitis. Pediatrics. 1980;66:925-7.
Herndon CD, Rink RC, Cain MP, et al. In situ Malone antegrade continence enema in 127 patients: a 6-year experience. J Urol. Oct 2004;172(4 Pt 2):1689-91. [Medline].
Foley PT, Sithasanan N, McEwing R, et al. Enteric duplications presenting as antenatally detected abdominal cysts: is delayed resection appropriate?. J Pediatr Surg. Dec 2003;38(12):1810-3. [Medline].
Ladd W, Gross RE. Surgical treatment of duplication of the alimentary tract: Enterogenous cysts, enteric cysts, or ileum duplex. Surg Gynecol Obstet. 1940;70:295-307.
Moss RL, Kalish LA, Duggan C, et al. Clinical parameters do not adequately predict outcome in necrotizing enterocolitis: a multi-institutional study. J Perinatol. Oct 2008;28(10):665-74. [Medline].
Bell MJ, Ternberg JL, Feigin RD, Keating JP, Marshall R, Barton L. Neonatal necrotizing enterocolitis. Therapeutic decisions based upon clinical staging. Ann Surg. Jan 1978;187(1):1-7. [Medline].
Hooker RL, Hernanz-Schulman M, Yu C, et al. Radiographic evaluation of intussusception: utility of left-side-down decubitus view. Radiology. Sep 2008;248(3):987-94. [Medline].
Roskind CG, Ruzal-Shapiro CB, Dowd EK, et al. Test characteristics of the 3-view abdominal radiograph series in the diagnosis of intussusception. Pediatr Emerg Care. Nov 2007;23(11):785-9. [Medline].
Sizemore AW, Rabbani KZ, Ladd A, et al. Diagnostic performance of the upper gastrointestinal series in the evaluation of children with clinically suspected malrotation. Pediatr Radiol. May 2008;38(5):518-28. [Medline].
Fazio VW, Cohen Z, Fleshman JW, et al. Reduction in adhesive small-bowel obstruction by Seprafilm adhesion barrier after intestinal resection. Dis Colon Rectum. Jan 2006;49(1):1-11. [Medline].
Shah U, Shafiq Y, Khan MA. Gastrograffin use in distal intestinal obstruction syndrome of cystic fibrosis. J Ayub Med Coll Abbottabad. Jan-Mar 2007;19(1):58-60. [Medline].
Yagci G, Kaymakcioglu N, Can MF, et al. Comparison of Urografin versus standard therapy in postoperative small bowel obstruction. J Invest Surg. Nov-Dec 2005;18(6):315-20. [Medline].
Gul A, Tekoglu G, Aslan H, et al. Prenatal sonographic features of esophageal and ileal duplications at 18 weeks of gestation. Prenat Diagn. Dec 15 2004;24(12):969-71. [Medline].
Dordelmann M, Rau G, Bartels D, et al. Evaluation of portal venous gas detected by ultrasound examination for diagnosis of NEC. Arch Dis Child Fetal Neonatal Ed. Sep 11. [Epub ahead of print] 2008.
Faingold R, Daneman A, Tomlinson G, Babyn PS, Manson DE, Mohanta A. Necrotizing enterocolitis: assessment of bowel viability with color doppler US. Radiology. May 2005;235(2):587-94. [Medline].
Kaiser AD, Applegate KE, Ladd AP. Current success in the treatment of intussusception in children. Surgery. Oct 2007;142(4):469-75; discussion 475-7. [Medline].
Ramachandran P, Gupta A, Vincent P, et al. Air enema for intussusception: is predicting the outcome important?. Pediatr Surg Int. Mar 2008;24(3):311-3. [Medline].
[Best Evidence] Abbas S, Bissett IP, Parry BR. Oral water soluble contrast for the management of adhesive small bowel obstruction. Cochrane Database Syst Rev. Jul 18 2007;CD004651. [Medline].
James DC, Lessen R. Position of the American Dietetic Association: promoting and supporting breastfeeding. J Am Diet Assoc. Nov 2009;109(11):1926-42. [Medline].
Probiotics for prevention of necrotizing enterocolitis in preterm infants [database online]. Cochrane Database of Systematic Reviews: Al Faleh KM, Bassler D; 2008.
Draus JM Jr, Foley DS, Bond SJ. Laparoscopic Ladd procedure: a minimally invasive approach to malrotation without midgut volvulus. Am Surg. Jul 2007;73(7):693-6. [Medline].
Tsumura H, Ichikawa T, Murakami Y, et al. Laparoscopic adhesiolysis for recurrent postoperative small bowel obstruction. Hepatogastroenterology. Jul-Aug 2004;51(58):1058-61. [Medline].
Sola JE, Tepas JJ 3rd, Koniaris LG. Peritoneal Drainage versus Laparotomy for Necrotizing Enterocolitis and Intestinal Perforation: A Meta-Analysis. J Surg Res. Jun 6 2009;[Medline].
Banieghbal B, Beale PG. Minimal access approach to jejunal atresia. J Pediatr Surg. Aug 2007;42(8):1362-4. [Medline].
Kozlov Y, Novogilov V, Yurkov P, Podkamenev A, Weber I, Sirkin N. Keyhole approach for repair of congenital duodenal obstruction. Eur J Pediatr Surg. Mar 2011;21(2):124-7. [Medline].
Jawaheer J, Khalil B, Plummer T, et al. Primary resection and anastomosis for complicated meconium ileus: a safe procedure?. Pediatr Surg Int. Nov 2007;23(11):1091-3. [Medline].

