Volvulus

Question 1

Definition of volvulus

Answer 1

A volvulus can be defined as a rotation of a loop of bowel around the axis of its mesentery that results in compromised blood flow and closed loop bowel obstruction which can lead to ischaemia

Question 2

Aetiology of volvulus

Answer 2

• The areas usually affected:
• SIGMOID volvulus (80% of cases):
◦ Large bowel obstruction caused by sigmoid colon twisting on sigmoid mesocolon

					• Caecal volvulus (20% of cases):
						◦  Usually due to developmental failure that increases risk of caecal volvulus

Question 3

Risk factors for sigmoid volvulus

Answer 3

◦ Older patients
◦ Chronic constipation
◦ Neurological conditions (e.g Parkinson’s)
◦ Chagas’ disease
◦ Long mesentery/ long sigmoid colon

Question 4

Risk factors for caecal volvulus

Answer 4

◦ All ages
◦ Adhesions
◦ Pregnancy
◦ Mobile caecum

Question 5

Pathophysiology of volvulus

Answer 5

• The bowel twisting upon its own mesentery can reduce the blood flow to the bowel and greatly increase the risk of bowel ischaemia
• Moreover, it would create a strangulating closed loop bowel obstruction

• If the twisting of the colon also affects the superior mesenteric artery, the small intestine and a portion of the colon can become ischaemic

Question 6

History and Examination of volvulus

Answer 6

• Absolute constipation: earlier sign if large bowel affected
• Nausea/vomiting: earlier sign of small bowel volvulus (can be bilious)
• Abdominal pain: SEVERE and SUDDEN onset, can be colicky
• Abdominal distention
• Abdominal tenderness
• Tachycardic
• May have absent or tinkling bowel sounds

Question 7

Investigations for volvulus

Answer 7

• FBC
• U&Es
• CT scan Abdomen and Pelvis with contrast:
◦ Can identify the site and cause +more sensitive
◦ Would show dilated sigmoid colon with ‘whirl sign’ due to twisting of mesentery around base

• Abdominal X-Ray: Likely to show large, dilated loop of colon. Can see a COFFEE-BEAN sign arising from left iliac fossa

Question 8

Treatment of volvulus

Answer 8

Stable patient:
1) Treat conservatively initially:
◦ Most patients treated conservatively with DECOMPRESSION by rigid sigmoidoscopy and insertion of a flatus tube (left in situ for up to 24 hours)

+ Supportive care: NG tube, IV fluid resuscitation

Obstruction with ischaemia (unstable):
◦ If unstable, suspected ischaemia, failed conservative management etc
◦ OPEN LAPAROTOMY: with Hartman’s procedure, check for ischaemic bowel and remove

+ Supportive care: NG Tube and aggressive IV fluid resuscitation

Question 9

Complications of volvulus

Answer 9

• Bowel ischaemia leading to necrosis, perforation and fatal peritonitis
• Bowel resection related short gut syndrome: due to loss of bowel
• Adhesions due to surgery

Question 10

Prognosis of volvulus

Answer 10

Prognosis depends on degree of intestinal ischaemia and necrosis
There is a slight risk of recurrence