Gastroschisis

Definition

• Direct abdominal defect that causes a portion of the intestines and other abdominal organs to herniate WITHOUT a covering membrane/peritoneal sac
• Typically located on the right side of the umbilicus
• Approximately 10–20% of cases are associated with additional congenital anomalies.
  • Commonly reported associated abnormalities include undescended testes, Meckel’s diverticulum, and intestinal duplication.

Diagnosis

• Identified via ultrasound during prenatal screening
• Elevated AFP can help confirm the diagnosis
  • Levels of AFP tend to be higher in Gastroschisis compared to Omphalocele

Epidemiology/Prognosis

• Occurs in 3-4 out of 10000 births
• Outcomes are variable, but are highly dependent on the amount of organs/intestines that have herniated and the prior level of prenatal care
  • Survival rates are > 90%

Embryology/Pathophysiology

• During normal embryologic development, the intestinal tract physiologically herniates into the umbilical cord at approximately the sixth week of gestation, with expected return to the abdominal cavity by around the twelfth week.
• In gastroschisis, this process is disrupted, most commonly attributed to an ischemic insult to the developing abdominal wall, which impairs normal closure and results in persistent herniation of the abdominal contents.

Surgical/Medical Management

• Infants with gastroschisis are frequently delivered via cesarean section to minimize the risk of additional bowel injury during passage through the vaginal canal, although the mode of delivery may ultimately be individualized based on obstetric considerations.
• The overarching treatment goal is reduction of the herniated intestinal contents into the abdominal cavity, followed by closure of the fascial and skin defects.
• Management strategies are influenced by several factors, including the size and type of the defect, the size and gestational maturity of the infant, and the presence of associated comorbidities.
• Immediately after delivery, the exposed bowel is typically covered with sterile saline-soaked dressings and enclosed in a clear plastic wrap or silo. This approach helps maintain moisture and normothermia while allowing continuous visual assessment of the herniated intestines.
• Management includes either a surgical approach vs staged approach
  • In a primary surgical approach, the bowel is carefully evaluated for evidence of atresia, necrosis, or vascular compromise before being reduced into the abdominal cavity. In some cases, the umbilical cord may be utilized as a biologic dressing to facilitate closure.
  • In a staged approach, a silo is placed over the herniated viscera, allowing for gradual, serial reduction of the bowel into the abdominal cavity over several days prior to definitive closure.

Anesthetic Considerations

Preoperative

• Obtain a CBC, CMP and T&S
  • Blood loss is typically unexpected however there will be lots of evaporative losses than sometimes may be best treated with blood
  • Evaluate whether there are any electrolyte issues
• NGT placement to decompress the stomach and decrease the risk of aspiration
• Address any other comorbidities (VACTERL) associated with the pathology

Intraoperative

• Standard ASA Monitors
  • Temperature will be particularly important given the large amount of heat loss from the open abdomen
• Induction
  • Position the patient in reverse trendelenberg to minimize the pressure from the abdominal contents on the lungs
  • RSI to minimize aspiration risk
• Lines
  • PIVs for resuscitation
  • Arterial Line
  • Central Lines for CVP monitoring and postoperative parenteral nutrition administration
• Maintenance
  • Patient can be maintained w/ either volatile or IV anesthetics
  • Avoid N2O due to risk of bowel distension
  • Maintain paralysis to help with abdominal closure
  • When surgical team is closing the abdomen, have close discussion with surgical team as this may cause decreased diaphragmatic excursion, compression of the lungs, increased airway pressures.
    • If at any point there are an increase in the peak inspiratory pressures > 35 or intra-abdominal pressure > 20, there should be an active discussion with the surgical team about reopening and performing a staged repair.

Postoperative

• Disposition to the NICU
• Anticipate post operative ventilation requirements
• Continue to monitor intra-abdominal pressures
• Early enteral feeding and TPN discontinuation can decrease length of stay and infection risk

Resources

• Gropper M, et al. Miller's Anesthesia. Chapter 77: Pediatric Anesthesia. Section: Omphalocele and Gastroschisis. 9th ed.
• Ledbetter DJ. Gastroschisis and Omphalocele. Surg Clin North Am. 2006;86(2):249-60. PubMed