Abdominal Wall Disorders

Pediatric Surgery
Dr Jacob Langer discusses abdominal wall defects with Dr. Todd Ponsky.
Edited by Ian C. Glenn, MD and Sophia Abdulhai, MD

An interactive discussion about gastroschisis and omphalocele between Todd Ponsky, MD and Jacob "Jack" Langer, MD. Dr. Langer is professor of surgery at the University of Toronto and Head of the Division of General and Thoracic Surgery at The Hospital for Sick Children in Toronto, Canada.

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Prenatal counseling for gastroschisis

  • Most patients have no other associated anomalies. Karyotype is typically not indicated.
  • The bowel is damaged in the intrauterine environment.

 Mode of Delivery

  • Mode of delivery is controversial, with older literate favoring C-section.
  • However, multiple, more recent studies show no advantage to C-section over vaginal delivery.

Timing of Delivery

  • Timing of delivery also remains controversial. There are no large, randomized trial investigating early delivery. Some retrospective studies show an advantage to early delivery, while other studies do not. At The Hospital for Sick Children (SickKids), patients are delivered around 37 weeks EGA.
  • The mean EGA for onset of labor has been shown to be earlier in gastroschisis pregnancies (possibly due to inflammatory mediators produced by the bowel).
  • Labor is typically induced at 37 weeks at SickKids, however there is not strong evidence supporting this practice.

Location of Delivery

  • Delivery in a perinatal center may be beneficial, but there not prospective, randomized trials in this area.

Management of simple gastroschisis

  • The patient should be transported and/or nursed on his side (typically right-side down).
  • The patient should NOT be placed in the supine position due to risk for kinking of the mesentery.
  • Nasogastric tube should be placed and the patient’s body temperature should be controlled.
  • Bedside closure should be performed if the bowel is not too thickened and does not have excessive peel.

Bedside reduction of gastroschisis

  • Dr. Langer places the bowel into a silo and administers a small amount of sedation, without intubation.
  • The bowel should be carefully reduced into the abdomen. If the patient tolerates this and intraabdominal pressures are kept below 20 mmHg (although this does not always need to be measured), the silo may be removed.
  • The umbilical cord stump is placed over the abdominal wall defect, and this is covered with an occlusive dressing (such as Tegaderm or DuoDERM), which is left in place approximately 5 days. No suture is required.
  • Baird, et al demonstrated that flap (or "plastic closure”) has superior outcomes to fascial (sutured) closure, including a lower requirement for umbilical hernia repair. Reference: Youssef F, Gorgy A, Arbash G, Puligandla PS, Baird RJ. "Flap versus fascial closure for gastroschisis: a systematic review and meta-analysis.” J Pediatr Surg. 2016 May;51(5):718-25 (Pubmed)

Role of intubation

  • There is no strong evidence for or against intubation.
  • Gastroschisis may be intubated intubated prior to arrival.
  • Intubation may potentially be avoided with adequate pain control prior to reduction

Role of silo placement

  • Dr. Langer uses a silo in every patient, but many have their bowel reduced immediately.
  • Not all patients require a staged closure with silo.
  • Disadvantages of staged closure
    • Abdominal wall defect increases in size
    • Greater risk of bowel re-herniation
    • Infection risk
  • If the patient can require one-stage closure at the bedside, it should be performed.

Associated Intestinal Atresia

  • Likely there is a 5-10% incidence of intestinal atresia associated with gastroschisis.
  • There are likely multiple, different types of intestinal atresias in gastroschisis, including so-called "vanishing gastroschisis.”
  • Patients with vanishing gastroschisis have short bowel syndrome.

Management of associated intestinal atresias

  • Three management styles (without strong evidence supporting any single approach)
    • Repair of the atresia at the time of abdominal wall closure
    • Stoma and mucous fistula creation with later restoration of intestinal continuity
    • Return of bowel to the abdomen and wait a few months for atresia repair
  • Dr. Langer states that if the bowel appears healthy without excessive presence of peel/rind, he will repair the atresia at the time of abdominal wall closure.
  • Stomas are used when there is necrotic intestine which must be resected.
    • If the bowel can all be reduced, the stomas may be brought out of the umbilicus.
    • If the bowel cannot all be reduced, the stomas may be brought out of the silo until the bowel is reduced.

 Awaiting bowel function

  • Patients are usually given 4 weeks of life to have pass meconium before investigations are undertaken to look for intestinal atresia or stenosis.
  • Pro-kinetic agents (e.g. metoclopramide IV) may be considered to improve time to bowel function.
  • The first study should be a contrast enema to evaluate for mechanical obstruction. The next study would be an upper GI series.
  • If these studies are equivocal, it is reasonable to wait until 6 weeks of life. If there has still been no bowel function, laparotomy is indicated.

Cryptorchidism in gastroschisis

  • The right testis is more commonly the abnormal side.
  • The testis is returned to the pelvis and in approximately 50% of cases the testis will ultimately make its way to the pelvis.

Prenatal counseling for omphalocele

  • Much higher incidence of associated anomalies and chromosomal abnormalities when compared with gastroschisis.
  • Karyotype analysis is encouraged.
  • Beckwith-Wiedemann syndrome is associated with omphalocele.
  • It is important to differentiate between small and large omphalocele, that latter of which contains the liver. Those containing a large amount of liver may be considered "giant omphalocele”.
  • Small omphalocele are more likely to be associated with abnormal chromosomes. These families are particularly encouraged to obtain karyotype.
  • Pulmonary hypoplasia is associated with giant omphalocele, and this is very difficult to diagnose prenatally. The family should be counseled accordingly. 

Mode, location, and timing of delivery

  • In small omphalocele, there is no rationale for routine C-section and no need for special delivery location or induction of labor.
  • Giant (and sometimes large) omphalocele is typically delivered via C-section, although this is not strongly evidence-based. There is no need for early deliver, but these patients should be delivered at a perinatal center with a team of experienced neonatologists.

Management of giant omphalocele

  • The goal is to reduce the viscera into the abdomen without direct damage to the viscera or compromise of blood supply.
  • Intraabdominal pressure measurement monitoring is very helpful in determining if the viscera may be reduced primarily, or if a staged closure is required.
  • Immediate reduction is not attempted in every patient, but it is reasonable to try in patients who are full term and without other significant comorbidities (such as congenital heart defects or pulmonary hypoplasia).

Using the omphalocele sac as the silo

  • The omphalocele sac may be used as the silo, with sequential ligation of the sac (using umbilical tape) as the viscera are reduced into the abdomen. For this to be achieved, the umbilical cord must originate from the top of the sac, rather than the side.
  • If the sac is violated, the patient must be taken to the OR for reduction and/or silo placement.
  • Alternatively, a DuoDERM may be placed over the omphalocele as it is gradually reduced into the abdomen. This has been described by Cristobal Abello in Colombia (see video below)

 Escharotic therapy

  • Escharotic therapy may be the only option for some cases of giant omphalocele. Silver sulfadiazine may be used for this.
  • In the interim, some patients who have undergone escharotic therapy will have spontaneous reduction of the omphalocele.

Technical Pearls

  • A component separation-type repair may be used to aid in abdominal closure
  • In patients with defects abutting the costal margin, the inferior portion of the defect is closed in the standard fashion and a patch is used for the superior portion.

Pentalogy of Cantrell

  • Ompahlocele may be associated with Pentalogy of Cantrell and thus have foramen of Morgagni hernia or absent pericardium.
  • These patients are typically treated with escharotic therapy due to their cardiac problems. When the patients undergo cardiac surgery, then a diaphragmatic patch may be placed from the thoracic route.
  • After these patients have recovered from cardiac surgery, the abdominal wall defect may be repaired electively.

GERD and omphalocele

  • These patients are typically not going to be candidates for a G tube if they are undergoing escharotic therapy.
  • However, radiology may be very helpful in placement of G tube prior to definitive abdominal wall repair. This can be transitioned to a GJ tube (or this may be placed primarily) to help manage the patient’s GERD.
  • Fundoplication prior to repair of the abdominal wall is not advisable.
  • When the patient is undergoing definitive repair of the abdominal wall defect, then a fundoplication may be performed at that time.
  • Partial mechanical gastric outlet obstruction may be caused by the liver. This can be diagnosed with a contrast study.

 Rotational anomalies

  • No need to perform Ladd’s procedure for non-rotation, as there is no risk for midgut volvulus.

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