Twisting of the intestine Flashcards
Types
Volvulus
Midgut malrotation
What is volvulus twisting
Complete twisting of a loop of intestine around its mesenteric attachment site
Where can a volvulus occur
Stomach SI Caecum Transverse colon Sigmoid colon
Clinical presentation of volvulus
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.
Pathophysiology of volvulus
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.
Aetiology of volvulus
Tends to develop in long-standing constipation with large, elongated, relatively atonic colon (particularly in the sigmoid)
Epidemiology of volvulus
More common in the elderly.
Rare in infants and children (when not with a malrotation)
Diagnosis fo volvulus
Plain abdominal X ray
Treatment of volvulus
(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.
Complications of volvulus
Recurrence.
If untreated: Perforation and peritonitis (life threatening)
What is midgut rotation
Twisting of the entire midgut about the axis of the superior mesenteric artery
Clinical presentation of midgut rotation
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.
Pathophysiology of midgut rotation
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.
Aetiology of midgut rotation
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.
Epidemiology of midgut rotation
1/500 live births.
90% are diagnosed within first year of life