Twisting of the intestine

Question 1

Types

Answer 1

Volvulus

Midgut malrotation

Question 2

What is volvulus twisting

Answer 2

Complete twisting of a loop of intestine around its mesenteric attachment site

Question 3

Where can a volvulus occur

Answer 3

Stomach
SI
Caecum
Transverse colon
Sigmoid colon

Question 4

Clinical presentation of volvulus

Answer 4

Rapid onset and bilious vomiting
Possible palpable abdominal mass
Ischaemia can lead to acute abdominal pain, abdominal distention and peritonitis.
Blood may pass per rectum.

Question 5

Pathophysiology of volvulus

Answer 5

Sections of colon filled with faeces and distended with gas can twist on its mesenteric pedicle to create closed loop obstruction.
This can cause backing of GI tract -> Vomiting and bleeding.
Bile from the bile duct is also backed up, hence the bilious vomiting.

Question 6

Aetiology of volvulus

Answer 6

Tends to develop in long-standing constipation with large, elongated, relatively atonic colon (particularly in the sigmoid)

Question 7

Epidemiology of volvulus

Answer 7

More common in the elderly.

Rare in infants and children (when not with a malrotation)

Question 8

Diagnosis fo volvulus

Answer 8

Plain abdominal X ray

Question 9

Treatment of volvulus

Answer 9

(Sigmoid) Decompression - sigmoidoscope is passed into the loop and a flatus tube alongside it. This produces a rush of liquid faeces and flatus and relief.
Surgery - Resection may be required in frequent recurrence.

Question 10

Complications of volvulus

Answer 10

Recurrence.

If untreated: Perforation and peritonitis (life threatening)

Question 11

What is midgut rotation

Answer 11

Twisting of the entire midgut about the axis of the superior mesenteric artery

Question 12

Clinical presentation of midgut rotation

Answer 12

Can be asymptomatic.
Intermittent intestinal obstruction.
If a volvulus develops, the obstruction will be complete. Bilious vomiting (green/yellow vomit).
Failure to thrive, anorexia, constipation and bloody stool.
Older children: Recurrent abdominal pain, cyclical vomiting.

Question 13

Pathophysiology of midgut rotation

Answer 13

A twisting of the midgut causes the passage of faecal matter to be slowed and obstructed.
This causes backing up of GI tract -> vomiting and bleeding.
Bile from the bile duct is also backed up, hence the bilious vomiting.

Question 14

Aetiology of midgut rotation

Answer 14

Congenital
At the 4th week of gestation, the GI tract is a straight tube in the abdomen. In the next 8 weeks, the midgut rotates and becomes fixed to the posterior abdominal wall. Arrest of development at any stage narrows the mesenteric base and impairs fixation.
This creates high risk of volvulus.

Question 15

Epidemiology of midgut rotation

Answer 15

1/500 live births.

90% are diagnosed within first year of life

Question 16

*Diagnosis of midgut rotation

Answer 16

Contrast studies:

Duodenojejunal junction is misplaced either at or to the right of the midline

Question 17

Treatment of midgut rotation

Answer 17

Surgery: Volvulus is a devastating complication, so corrected even if asymptomatic

Question 18

Complications of midgut rotation

Answer 18

Volvulus can develop

Leading to complete bowel obstruction and potentially a rupture -> life threatening peritonitis