[19] Volvulus Flashcards
(54 cards)
What is a volvulus?
The twisting of a loop of intestine around its mesenteric attachment, resulting in a closed loop obstruction
What happens to the affected bowel in a volvulus?
It can often become ischaemic due to a compromised blood supply, rapidly leading to bowel necrosis and perforation
Where do most volvuli occur?
At the sigmoid colon
What is the importance of volvuli?
It is the leading cause of bowel obstruction in many developing countries, and is tUKhe third most common cause in the UK and USA
What are the most common causes of bowel obstruction in the UK?
Maligancy and diverticular disease
Where else can volvuli occur?
Stomach
Small intestine
Caecum
Transverse colon
Why is the sigmoid colon most likely to get a volvulus?
Because the long mesentery of the sigmoid colon means that this segment of bowel is prone to twisting on its mesenteric base to form a volvulus
What are the risk factors for developing a volvulus?
Neuropsychiatric conditions Resident in nursing home Advanced age Chronic constipation or laxative Male gender Previous abdominal surgeries Diabetes mellitus
How will patients with a volvulus present?
With the clinical features of a bowel obstruction
How can the recurring nature of volvuli be relevant?
Means that the patient may have had a previous history of volvulus formation
What is the result of the distal location of the sigmoid colon on the presentation of a volvulus?
Vomiting is usually a late sign
Colicky pain, abdominal distention, and absolute constipation occur earlier
What will be found on examination in a volvulus?
The abdomen will be markedly distended, with increased bowel sounds and tympanic percussion
What should you be sure to examine for with a suspected volvulus?
Signs of perforation or generalised peritonism
Why is it important to examine for signs of perforation or generalised peritonism in a suspected volvulus?
As this is a surgical emergency
What are the main differential diagnoses to consider in a suspected volvulus?
Other causes of bowel obstruction, as well as severe constipation, pseudo-obstruction, and severe sigmoid diverticular disease
What investigations should be done in suspected volvulus?
Routine bloods
Imaging
What bloods should be checked in suspected volvulus?
Electrolytes
Calcium
TFTs
What is the purpose of checking TFTs in a suspected volvulus?
To exclude any pseudo-obstruction
What is the most decisive initial investigation for a suspected sigmoid volvulus?
An abdominal x-ray
What will be shown on abdominal x-ray in volvulus?
Will classically show a ‘coffee-bean sign’, arising from the left iliac fossa
What % of cases of volvulus have the coffee bean sign?
60-75% cases
What will be seen on a AXR in volvulus if the ileocaecal valve is incompetent?
There will be signs of small bowel dilation
When might a CT scan be warranted in suspected volvulus?
If the diagnosis remains unclear, or clinical features suggest a potential bowel ischaemia developing
What will CT imaging classically show with a volvulus?
A ‘whirl sign’ from the twisting mesentery around it’s base
