Volvulus

Question 1

A … is the twisting of a loop of intestine* around its mesenteric attachment, resulting in a closed loop bowel obstruction. The affected bowel can become ischaemic due to a compromised blood supply, rapidly leading to bowel necrosis and perforation.

Answer 1

A volvulus is the twisting of a loop of intestine* around its mesenteric attachment, resulting in a closed loop bowel obstruction. The affected bowel can become ischaemic due to a compromised blood supply, rapidly leading to bowel necrosis and perforation.

Question 2

Most volvuli occur at the … colon and are a common cause of large bowel obstruction in many countries (after malignancy and diverticular disease). They can also occur at the stomach, caecum, small intestine and transverse colon, but are much rarer.

Answer 2

Most volvuli occur at the sigmoid colon and are a common cause of large bowel obstruction in many countries (after malignancy and diverticular disease). They can also occur at the stomach, caecum, small intestine and transverse colon, but are much rarer.

Question 3

Most volvuli occur at the sigmoid colon and are a common cause of … bowel obstruction in many countries (after malignancy and diverticular disease). They can also occur at the stomach, caecum, small intestine and transverse colon, but are much rarer.

Answer 3

Most volvuli occur at the sigmoid colon and are a common cause of large bowel obstruction in many countries (after malignancy and diverticular disease). They can also occur at the stomach, caecum, small intestine and transverse colon, but are much rarer.

Question 4

The long … of the sigmoid colon (which increases with age) means that this segment bowel is more prone to twisting on its … base (Fig. 1) to form a volvulus than any other region. As such, this article will mainly focus on the risk factors, clinical presentation, and management of a sigmoid volvulus.

Answer 4

The long mesentery of the sigmoid colon (which increases with age) means that this segment bowel is more prone to twisting on its mesenteric base (Fig. 1) to form a volvulus than any other region. As such, this article will mainly focus on the risk factors, clinical presentation, and management of a sigmoid volvulus.

Question 5

*The word volvulus derives from the Latin ‘to …’

Answer 5

*The word volvulus derives from the Latin ‘to twist’

Question 6

The risk factors for developing a volvulus include: (6)

Answer 6

Increasing age
Neuropsychiatric disorders
Resident in a nursing home
Chronic constipation or laxative use
Male gender
Previous abdominal operations

Question 7

Clinical Features - volvulus

Answer 7

Patients with a volvulus will present with the clinical features of bowel obstruction.

As the sigmoid colon is located distally in the GI tract,vomiting is usually a late sign, whilst the colicky pain, abdominal distension, and absolute constipation occur earlier on in the clinical course.

Particularly noteworthy in cases of volvulus, compared to other causes of bowel obstruction, is the rapidity of onset (over a few hours) and degree of abdominal distension.

On examination, the abdomen is often very tympanic to percussion. Ensure to examine for signs of perforation or peritonism, as this indicates ischaemia or perforation and is a surgical emergency.

Question 8

Particularly noteworthy in cases of …, compared to other causes of bowel obstruction, is the rapidity of onset (over a few hours) and degree of abdominal distension.

Answer 8

Particularly noteworthy in cases of volvulus, compared to other causes of bowel obstruction, is the rapidity of onset (over a few hours) and degree of abdominal distension.

Question 9

Differential Diagnosis for volvulus?

Answer 9

The main differential diagnoses to consider are the alternative causes for bowel obstruction, as well as severe constipation, pseudo-obstruction, and severe sigmoid diverticular disease.

Question 10

Investigations for bowel obstruction presentation

Answer 10

All patients presenting with clinical features of bowel obstruction should be investigated accordingly. Routine bloods should be taken, including electrolytes, Ca2+, and TFTs to exclude any potential pseudo-obstruction.

The initial investigation for suspected bowel obstruction is a CT scan abdomen-pelvis with contrast, as this is much more sensitive and specific for bowel obstruction and also identifies the site and cause. CT imaging classically will demonstrate a very dilated sigmoid colon with a ‘whirl sign’, from the twisting mesentery around its base.

Some centres will perform an abdominal radiograph (AXR). This will classically show (in around 60-75% cases) a “coffee-bean sign” arising from the left iliac fossa (Fig. 2); if the ileocaecal valve is incompetent, the AXR will also show signs of small bowel dilatation.

Question 11

Some centres will perform an abdominal radiograph (AXR) in a bowel obstruction presentation

This will classically show (in around 60-75% cases) a “…-… sign” arising from the left iliac fossa (Fig. 2); if the ileocaecal valve is incompetent, the AXR will also show signs of small bowel dilatation.

Answer 11

Some centres will perform an abdominal radiograph (AXR). This will classically show (in around 60-75% cases) a “coffee-bean sign” arising from the left iliac fossa (Fig. 2); if the ileocaecal valve is incompetent, the AXR will also show signs of small bowel dilatation.

Question 12

All patients admitted with suspected sigmoid volvulus should be managed initially as per any patient with bowel obstruction. In particular, they should be examined for any signs of … and given …

Answer 12

All patients admitted with suspected sigmoid volvulus should be managed initially as per any patient with bowel obstruction. In particular, they should be examined for any signs of ischaemia and given fluid resuscitation.

Question 13

Conservative Management for sigmoid volvulus

Answer 13

Most patients with sigmoid volvulus are treated conservatively initially with decompression by sigmoidoscope and insertion of a flatus tube.

In sigmoidoscope decompression, the patient is placed in the left lateral position and a lubricated sigmoidoscope gently guided into the rectum. It is manoeuvred to locate the twisted bowel and once the sigmoidoscope is in the correct position, there will be a rush of air and liquid faeces as the obstruction is relieved.

A flatus tube is often left in situ for a period of time (up to 24 hours) after initial decompression to allow for the continued passage of contents and aid recovery of the affected area. In 25-50% of patients, this approach is unsuccessful and a formal decompression with a flexible sigmoidoscope is required.

Question 14

Most patients with sigmoid volvulus are treated conservatively initially with decompression by … and insertion of a flatus tube.

Answer 14

Most patients with sigmoid volvulus are treated conservatively initially with decompression by sigmoidoscope and insertion of a flatus tube.

Question 15

In sigmoidoscope …., the patient is placed in the … lateral position and a lubricated sigmoidoscope gently guided into the rectum. It is manoeuvred to locate the twisted bowel and once the sigmoidoscope is in the correct position, there will be a rush of air and liquid faeces as the obstruction is relieved.

Answer 15

In sigmoidoscope decompression, the patient is placed in the left lateral position and a lubricated sigmoidoscope gently guided into the rectum. It is manoeuvred to locate the twisted bowel and once the sigmoidoscope is in the correct position, there will be a rush of air and liquid faeces as the obstruction is relieved.

Question 16

A flatus tube is often left in situ for a period of time (up to 24 hours) after initial decompression to allow for the continued passage of contents and aid recovery of the affected area. In 25-50% of patients, this approach is unsuccessful and a formal decompression with a … … is required.

Answer 16

A flatus tube is often left in situ for a period of time (up to 24 hours) after initial decompression to allow for the continued passage of contents and aid recovery of the affected area. In 25-50% of patients, this approach is unsuccessful and a formal decompression with a flexible sigmoidoscope is required.

Question 17

The indications for surgery in sigmoid volvulus (which is usually a laparotomy for a Hartmann’s procedure) are: (3)

Answer 17

Colonic ischaemia or perforation
Repeated failed attempts at decompression
Necrotic bowel noted at endoscopy

The decision on which operation to perform will depend on the patient’s nutritional status, adequacy of blood supply, haemodynamic stability, and the presence of any perforation or peritonitis.

Patients with recurrent volvulus who are otherwise healthy may choose to have an elective procedure (most commonly sigmoidectomy with primary anastomosis) to prevent further recurrence.

Question 18

Patients with recurrent volvulus who are otherwise healthy may choose to have an elective procedure (most commonly … with primary anastomosis) to prevent further recurrence.

Answer 18

Patients with recurrent volvulus who are otherwise healthy may choose to have an elective procedure (most commonly sigmoidectomy with primary anastomosis) to prevent further recurrence.

Question 19

The main immediate complication of a sigmoid volvulus is of … and …. Longer term complications are mainly the risk of recurrence (occurring in up to 90% of patients) and complications from a stoma if placed.

Answer 19

The main immediate complication of a sigmoid volvulus is of bowel ischaemia and perforation. Longer term complications are mainly the risk of recurrence (occurring in up to 90% of patients) and complications from a stoma if placed.

Question 20

Overall mortality from surgery (for volvulus)

Answer 20

Overall mortality from surgery in these patients is high as they are generally old, frail and with multiple co-morbidities. There is also often a delay in getting these patients to theatre which contributes to their physiological compromise and high mortality.

Question 21

The second most common site for a volvulus to occur is at the …, accounting for around 25-40% of all colonic volvulus. There is a bimodal age of onset, in the 10-29 year group and then again in the 60-79 year group.

Answer 21

The second most common site for a volvulus to occur is at the caecum, accounting for around 25-40% of all colonic volvulus. There is a bimodal age of onset, in the 10-29 year group and then again in the 60-79 year group.

Question 22

Caecal volvulus:

Those in the younger group may have intestinal … or excessive … as the predisposing cause, whilst in older patients it is more associated with chronic …, distal …, or dementia.

Answer 22

Caecal volvulus:

Those in the younger group may have intestinal malformation or excessive exercise as the predisposing cause, whilst in older patients it is more associated with chronic constipation, distal obstruction, or dementia.

Question 23

Diagnosis is once again made on CT imaging, which shows a very distended caecum, a mesenteric “swirl” and small bowel obstruction. The management of a caecal volvulus is always … and … resection (assuming the patient is well enough).

Answer 23

Diagnosis is once again made on CT imaging, which shows a very distended caecum, a mesenteric “swirl” and small bowel obstruction. The management of a caecal volvulus is always laparotomy and ileocaecal resection (assuming the patient is well enough).

Question 24

Key points for volvulus …

Answer 24

Sigmoid volvulus are common in those from a nursing home, have dementia, or suffer with chronic constipation
Patients will present with features of bowel obstruction, in particular with a very distended and tympanic abdomen
Always assess for evidence of ischaemia or perforation, as mortality from surgery in these patients is high
In the absence of perforation or ischaemia, most patients can be treated with flatus tube decompression

Question 25

… volvulus: typical ‘coffee bean’ sign is described. Arises from left lower quadrant, haustra cannot be identified. Multiple air-fluid levels may be seen. Classical appearances often not present and a simple x-ray may not be diagnostic.

Answer 25

Sigmoid volvulus: typical ‘coffee bean’ sign is described. Arises from left lower quadrant, haustra cannot be identified. Multiple air-fluid levels may be seen. Classical appearances often not present and a simple x-ray may not be diagnostic.

Question 26

… volvulus: arises from the right lower quadrant, haustral pattern tends to be maintained. One air-fluid level seen. Classical appearances often not present and a simple x-ray may not be diagnostic.

Answer 26

Caecal volvulus: arises from the right lower quadrant, haustral pattern tends to be maintained. One air-fluid level seen. Classical appearances often not present and a simple x-ray may not be diagnostic.

Question 27

3, 6, 9 rule: As a general rule of thumb, dilatation of the … bowel > 3cm, the … bowel > 6cm or the … > 9 cm, is suggestive of abnormal dilatation.

Answer 27

3, 6, 9 rule: As a general rule of thumb, dilatation of the small bowel > 3cm, the large bowel > 6cm or the caecum > 9 cm, is suggestive of abnormal dilatation.

Question 28

Large bowel: Identification of the large bowel is based on the presence of …. These give the large intestines its sacculated appearance. On radiograph, these are seen as white lines, which do not cross the lumen of the large bowel.

Answer 28

Large bowel: Identification of the large bowel is based on the presence of haustra. These give the large intestines its sacculated appearance. On radiograph, these are seen as white lines, which do not cross the lumen of the large bowel.

Question 29

Small bowel: Identification of the small bowel is based on the presence of the valvulae …. These are circular folds, which help increase the surface area of the small intestines. On radiograph, these are seen as white lines which cross the lumen of the small bowel.

Answer 29

Small bowel: Identification of the small bowel is based on the presence of the valvulae conniventes. These are circular folds, which help increase the surface area of the small intestines. On radiograph, these are seen as white lines which cross the lumen of the small bowel.

Question 30

A sigmoid volvulus may resolve with a promptly placed … tube. Following this the patient should be considered for a definitive surgical procedure particularly if recurrent.

… volvulus more commonly requires immediate surgical intervention.

Immediate surgical intervention is also indicated if there is evidence of … or ischaemia.

Answer 30

A sigmoid volvulus may resolve with a promptly placed flatus tube. Following this the patient should be considered for a definitive surgical procedure particularly if recurrent. Caecal volvulus more commonly requires immediate surgical intervention. Immediate surgical intervention is also indicated if there is evidence of perforation or ischaemia.