Malrotation and volvulus — branching viva

Opening question

A three-day-old term neonate who fed and stooled normally has just vomited bright green bile. The baby is alert with a soft abdomen and the plain abdominal radiograph is reported as normal. What is the governing rule that drives this baby's management, what is the immediate plan, and why does neither the well-looking baby nor the normal film reassure you? [1] [2]

Branch 1 — the investigation and the unstable child

Take the same child. Which investigation confirms the diagnosis, and what are the signs of malrotation and of an actual volvulus on it? What does the ultrasound add? Now the baby becomes lethargic, the abdomen grows tender, and there is blood in the stool — what changes about your plan, and why must a scan never delay this child? [2]

Branch 2 — the operation

You have decided to operate. Describe the Ladd procedure step by step: how you untwist the volvulus, what you do to the bands and the mesentery, and why you remove the appendix. In which direction is the volvulus detorsed, and why? What do you do if bowel viability is borderline? [6]

Branch 3 — the older child and the incidental finding

Now picture a fourteen-year-old with two years of recurrent green vomiting, intermittent central pain and a falling weight centile, labelled as cyclic vomiting. Why has the diagnosis been missed, what lifts it out of the functional bin, and what investigation confirms it? Finally, an asymptomatic two-year-old is found incidentally to have malrotation — must every such child be operated on, and what principle governs the decision? [5] [2]

Closing — the one sentence

In one sentence, what is the reflex that protects the midgut in malrotation and volvulus, and why does time to untwisting outweigh every other consideration in this disease? [2] [1]