NECROTIZING ENTEROCOLITIS PROCEDURES

necrotizing enterocolitis procedures:
• Upper GI (with or without) small bowel follow-through
o This procedure is a definitive way to diagnose the presence or absence of intestinal volvulus.
o Always consider intestinal volvulus if bilious vomiting is present, especially in the term infant.
o Because the presence of volvulus is a surgical emergency, it is an important diagnosis to exclude in a neonate with abdominal symptoms.
o Perform before contrast enema because the presence of contrast in the colon can obscure pertinent findings.

• Contrast enema
o This procedure is a definitive way to diagnose a distal obstruction.
o Always use a water-soluble contrast agent because of the risk of perforation. Contrast enemas are contraindicated in the presence of perforation. Consider carefully the clinical risks and benefits before undertaking this evaluation in the unstable and/or acutely ill infant.
o Contrast enema findings are important for the differential diagnosis of intestinal abnormalities because distal obstructions, such as meconium plug, small left colon syndrome, and Hirschsprung disease, may cause symptoms in the baby without fulminant systemic collapse.

• Rectal biopsy
o This procedure is the criterion standard for diagnosing Hirschsprung disease.
o This biopsy is a pediatric surgical procedure that is performed either as a bedside suction biopsy or as an open biopsy.
o Ganglion cells in the biopsied specimen definitively rule out the diagnosis. The absence of cells, while suspicious for disease, merely may be the result found in the particular specimen obtained and is not 100% conclusive.

• Placement of a peripheral arterial line may be helpful at the beginning of the patient's evaluation to facilitate serial arterial blood sampling and invasive monitoring.

• If the baby is deteriorating rapidly, with apnea and/or signs of impending circulatory and respiratory collapse, airway control and initiation of mechanical ventilation is indicated.

• Abdominal decompression
o Decompression is essential at the first sign of abdominal pathology.
o If possible, use a large-bore catheter with multiple side holes to prevent vacuum attachment to the stomach mucosa.
o Set the catheter for low continuous suction and monitor output.
o If copious amounts of gastric/intestinal secretions are removed, consider IV replacement with a physiologically similar solution, such as lactated Ringer solution.

• Paracentesis
o Ascites can develop during fulminant NEC and can compromise respiratory function. Remove ascites using intermittent paracentesis.
o Ultrasonographic guidance can facilitate paracentesis.
o After completing the procedure, significant fluid shifts between the intravascular and extravascular spaces are possible, so avoid removing large amounts of fluid at one time.

• Place an intra-abdominal drain as an alternative to laparotomy if the baby is not a surgical candidate.

Histologic Findings:
Inspecting the affected bowel reveals mucosal ischemia, progressing to cell death and sloughing. Necrosis can be limited to the mucosal layer, observed radiographically as pneumatosis, or it can affect the full wall, resulting in perforation with subsequent peritonitis. Necrotic and/or perforated intestine must be resected.