Malrotation/ Vulvulus

Question 1

Causes

Answer 1

At 4 weeks gestation, the GI system is a straight tube centrally located in the abdomen. During the ensuing eight weeks, the midgut rotates and becomes fixed to the posterior abdominal wall.

During rotation of the small bowel in foetal life, if the mesentery is NOT fixed at the duodenojejunal junction or the ileocaecal region, its base may be SHORTER and narrower than normal and is predisposed to volvulus.

Question 2

Presentation

Answer 2

Usually diagnosed within the first month of life

The TWO main presentations of malrotation:

• Obstruction
• Obstruction with compromised blood supply (ischaemia/ necrosis) -> This is when you get bloody stool

1. Obstruction with bilious vomiting within the first few days of life (usually 1-3 days) but it can occur later
2. Bilious vomiting
3. Abdominal pain
4. Tenderness from peritonitis or ischaemic bowel
5. Palpable mass is sometimes felt

NOTE: Non-rotation may be asymptomatic and be detected as an incidental finding during GI imaging for some other purpose. Malrotation may cause intermittent symptoms of intestinal obstruction but if a volvulus develops, the obstruction is typically complete

Question 3

Investigation

Answer 3

Abdominal examination

Basic observations

Bloods- FBC, U&Es, LFTs, glucose

URGENT GI contrast study (barium swallow) - any child with dark green vomiting needs this to assess intestinal rotation

Question 4

Management

Answer 4

NOTE: If there are signs of vascular compromise, an URGENT LAPAROTOMY is needed
* This is a SURGICAL EMERGENCY
* When a volvulus occurs, the superior mesenteric arterial blood supply to the small intestine and proximal large intestine is compromised (can lead to infarction)

Ladd procedure- detorting the bowel and surgically dividing the Ladd bands
* This is either done laparoscopically (if elective or non-urgent) OR during open laparotomy (emergency or urgent)
* Untwist volvulus, mobilize duodenum, place bowel in non-rotated position and remove necrotic bowel

The bowel is placed in the non-rotated position with the duodenojejunal flexure on the RIGHT and the caecum and appendix on the LEFT

NOTE: the appendix is usually removed to avoid diagnostic confusion in case the child presents again with an acute abdomen

Antibiotics (cefazolin)

Question 5

Complications

Answer 5

Bowel infarction and necrosis

Short gut syndrome (related to bowel resection)

Ladd procedure-related volvulus or adhesion small bowel obstruction

Prognosis

Mortality is determined by bowel necrosis