Volvulus

Question 1

What is volvulus?

Answer 1

Rotation of a loop of bowel around the axis of its mesentery that results in bowel obstruction + potential ischaemia.

Question 2

Which areas are commonly affected in volvulus?

Answer 2

Sigmoid colon: 80% (long mesentery)

Caecum: 20%

Volvulus Neonatorum: occurs in neonates, normally midgut

Question 3

Why is caecal volvulus less common?

Answer 3

In most people (80%) the caecum is a retroperitoneal structure so not at risk of twisting

Question 4

What obstruction is caused by caecal volvulus?

Answer 4

Most proximal part of large bowel hence will not really cause LBO but may cause SBO

Question 5

List 5 risk factors for sigmoid volvulus

Answer 5

Elderly
Chronic constipation
Neurological disorders (PD, DMD)
Psychiatric disease (those on anti-psychotics)
Chagas disease (parasite)/ other Parasitic infections

Question 6

What increases risk of sigmoid volvulus?

Answer 6

RFs increase chance of having chronic constipation + slow transit
Results in development of redundant sigmoid colon which becomes prone to twisting

Question 7

Give 3 caecal volvulus associations

Answer 7

All ages
Adhesions
Pregnancy

Question 8

How does volvulus differ from other causes of bowel obstruction?

Answer 8

Rapidity of onset (few hours)
+
Degree of abdominal distension

Question 9

What causes volvulus in neonates?

Answer 9

Malrotation: incomplete rotation of the midgut causing a failure in the attachment of the caecum to the posterior abdominal wall

Question 10

List 4 symptoms of volvulus

Answer 10

Absolute constipation
Abdominal bloating
Abdominal pain
Vomiting (late, secondary to BO)

Question 11

List 2 signs of volvulus

Answer 11

Abdominal distension (tympanic to percussion)
Tinkling bowel sounds (intestinal obstruction)

Question 12

What is seen on abdominal x-ray in sigmoid volvulus?

Answer 12

Coffee bean sign
LBO (large, dilated loop of colon, often with air-fluid levels)

Question 13

What is seen on abdominal x-ray in caecal volvulus?

Answer 13

Embryo sign
SBO

Question 14

What is first line imaging in volvulus?

Answer 14

AXR

Question 15

What imaging provides a definitive diagnosis of sigmoid volvulus? What is seen?

Answer 15

CT AP with contrast
Whirl sign

Question 16

What bloods should be performed in suspected volvulus?

Answer 16

FBC
U+Es
CRP
Clotting
VBG: pH + serum lactate in context of potential bowel ischaemia

Question 17

Describe initial management of sigmoid volvulus

Answer 17

Insert NG tube + urinary catheter
IV fluids
Analgesia

Question 18

Describe conservative management of sigmoid volvulus

Answer 18

Decompression by sigmoidoscope + insertion of flatus tube

Question 19

Describe sigmoidoscope decompression

Answer 19

1. Patient in left lateral position, lubricated sigmoidoscope inserted into rectum
2. Manoeuvred to locate twisted bowel + with gentle pressure volvulus untwisted
3. Once sigmoidoscope in correct position there will be a rush of air + liquid faeces as obstruction is relieved

Question 20

Describe use of a flatus tube

Answer 20

Flatus tube often left in situ (up to 24h) after initial decompression to allow continued passage of contents + aid recovery of affected area

Question 21

When is emergency surgery indicated for sigmoid volvulus?

Answer 21

If evidence of bowel ischaemia or perforation
If repeat failed endoscopic decompression

Question 22

What surgery is usually performed if required for sigmoid volvulus?

Answer 22

Sigmoid colectomy
Often as a laparotomy + Hartmann’s procedure

Question 23

What may patients with recurrent volvulus choose to undergo?

Answer 23

Elective procedure
Either sigmoid colectomy with primary anastomosis or end colostomy

Question 24

Give 2 complications of sigmoid volvulus

Answer 24

Bowel ischaemia + perforation
Recurrence

Question 25

What is seen on CT in caecal volvulus?

Answer 25

Distended caecum
Mesenteric swirl
SBO

Question 26

Describe management of caecal volvulus

Answer 26

Bowel resection, typically high hemicolectomy

Question 27

What triad of symptoms characterise gastric volvulus?

Answer 27

Borchardt’s triad
Severe epigastric pain
Retching
Inability to pass an NG tube