What is the most appropriate next step for a newborn with abdominal distention, tenderness upon palpation, absent bowel sounds, and no meconium passage for 48 hours?

Immediate Pediatric Surgical Referral

The most appropriate next step is B - Refer to pediatric surgery immediately, as this newborn presents with signs of a surgical emergency requiring urgent evaluation before any diagnostic imaging. 1

Clinical Reasoning

This newborn presents with the classic tetrad of neonatal intestinal obstruction:

• Abdominal distention
• Tenderness upon palpation (suggesting peritonitis or bowel compromise)
• Absent bowel sounds
• Failure to pass meconium for 48 hours 2

The combination of absent bowel sounds with abdominal tenderness mandates immediate surgical evaluation before any diagnostic imaging, as this suggests peritonitis or bowel compromise. 1

Why Immediate Surgical Referral Takes Priority

Life-Threatening Differential Diagnoses

The American College of Radiology emphasizes that this clinical presentation may indicate several surgical emergencies: 1

• Midgut volvulus with malrotation: 20% of neonates with bilious vomiting in the first 72 hours have midgut volvulus requiring urgent surgery 1
• Intestinal atresia (duodenal, jejunal, or ileal)
• Hirschsprung disease with complications
• Necrotizing enterocolitis 3

Critical Timing Considerations

Never delay surgical consultation for imaging studies in a neonate with peritoneal signs (tenderness and absent bowel sounds), as this can lead to significant morbidity and mortality. 1 The presence of abdominal tenderness with absent bowel sounds suggests bowel compromise that may progress rapidly to perforation or necrosis. 1

Why Not the Other Options First?

Barium Enema Study (Option A)

• While contrast enema is the diagnostic imaging procedure of choice for suspected distal obstruction, it should only be performed after surgical consultation in a patient with peritoneal signs 1, 4
• Contrast enema can be both diagnostic and therapeutic for conditions like meconium plug syndrome, but requires surgical backup 5
• The presence of tenderness and absent bowel sounds suggests a more urgent situation than simple meconium plug 1

Rectal Suction Biopsy (Option C)

• This is the definitive diagnostic test for Hirschsprung disease, but is not the immediate next step in an acutely ill neonate with peritoneal signs 1
• Hirschsprung disease is in the differential, but the acute presentation with tenderness requires surgical evaluation first 3
• This diagnostic procedure can be performed after stabilization and surgical assessment

Appropriate Diagnostic Sequence After Surgical Consultation

Once pediatric surgery is involved, the typical algorithm proceeds as follows:

1. Plain abdominal radiographs as the first imaging study to demonstrate dilated bowel loops, air-fluid levels, and presence/absence of distal gas 1, 4
2. Contrast enema if distal obstruction is suspected and the patient is stable enough for the procedure 1, 4
3. Upper GI series if malrotation/volvulus remains a concern 4

Common Pitfall to Avoid

The most critical error would be delaying surgical consultation to pursue diagnostic imaging first. 1 In neonatal intestinal obstruction with peritoneal signs, surgical evaluation must occur simultaneously with or before diagnostic workup, as 11% of neonates with lower GI causes require urgent intervention. 1