The 36-hour-old with bilious vomiting and a normal abdominal film
A 2.6 kg term male, born by spontaneous vaginal delivery at 39 weeks with Apgar 9/10, is now 36 hours old. He fed well initially but over the last 6 hours has had three episodes of green-tinged emesis and now refuses feeds. He is lethargic, has a sunken fontanelle, capillary refill of 4 seconds, heart rate 178/min, and a capillary glucose of 2.1 mmol/L. His abdomen is mildly distended but soft and non-tender; there is no guarding. A supine abdominal radiograph shows a few non-specific gas-filled loops without dilated bowel, no free air, and no pneumatosis. His mother is G2P2, and the pregnancy was uncomplicated with no polyhydramnios. His weight is 8% below birth weight.
1. What is your leading diagnosis, and why does the radiograph not exclude it?
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The leading diagnosis is malrotation with midgut volvulus. Bilious emesis in any neonate is a surgical emergency until proven otherwise, and the timing (day 2, after a period of normal feeding) fits volvulus or obstruction rather than duodenal atresia (which usually presents on day 1 with no prior tolerance of feeds and often with polyhydramnios).
The normal radiograph is not reassuring: in early or intermittent volvulus the bowel distal to the twist may still contain gas, and the plain film can be entirely non-specific or even normal in up to a quarter of cases. The absence of dilated loops, free air, or pneumatosis does not exclude ischaemia or a closed-loop obstruction.
The next step is an urgent upper GI contrast study (not a barium enema, which is for suspected intussusception or Hirschsprung work-up). The classical finding is a spiral/corkscrew duodenal course with the duodenojejunal flexure displaced to the right of the midline and below the level of the pylorus. If the child is unstable or the study cannot be obtained promptly, proceed to laparotomy - do not delay for imaging in a shocked infant.
2. Prioritise your immediate management in the first hour, before imaging.
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Resuscitate and decompress, then image:
- Airway/breathing - assess; the child is lethargic with tachycardia, so give oxygen and monitor.
- Circulation - two large-bore IV accesses; 10–20 mL/kg crystalloid bolus and reassess (he is 8% down with delayed refill and a sunken fontanelle).
- Glucose - 2.1 mmol/L is hypoglycaemia; give 2 mL/kg of 10% dextrose IV and start a maintenance glucose-containing infusion.
- Decompression - insert a nasogastric tube on free drainage (do not clamp) and record the aspirate volume and colour.
- Investigations - full blood count, electrolytes, blood gas with lactate, blood culture, cross-match.
- Antibiotics - broad-spectrum cover for possible ischaemia/translocation once cultures are taken.
- Surgical referral immediately and arrange the upper GI study as a priority while resuscitation continues in parallel.
Avoid giving enteral feeds or antiemetics, and do not give opioids before surgical review as they may mask deterioration.
3. The upper GI study confirms malrotation with a corkscrew appearance. At laparotomy there is 20 cm of frankly necrotic midgut. Discuss the intraoperative decision-making and the long-term nutritional consequence.
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Intraoperative decisions:
- Detorse the volvulus in a counter-clockwise direction and assess viability.
- Resect only clearly non-viable bowel; use a second-look laparotomy at 24–48 hours rather than resecting borderline bowel at the first operation. This preserves length in a neonate where every centimetre matters.
- Perform a Ladd procedure: divide Ladd's bands, widen the mesenteric base, place the caecum in the left upper quadrant, and appendicectomy (to avoid future diagnostic confusion).
- Do not attempt primary anastomosis in the presence of ischaemia or instability; consider a temporary stoma.
Long-term consequence: loss of a substantial length of midgut risks short bowel syndrome. In a 2.6 kg neonate, residual small bowel of ~20–25 cm with an intact ileocaecal valve may still permit enteral autonomy, but the child will need long-term parenteral nutrition, careful monitoring for cholestasis and intestinal failure-associated liver disease, micronutrient surveillance (B12, fat-soluble vitamins, zinc, iron), and gradual enteral advancement. Prognosis depends on the length and function of the remaining bowel, the presence of the ileocaecal valve and colon, and prevention of catheter-related sepsis.