Bowel Obstruction

Question 1

What are the 3 main causes of bowel obstruction?

Answer 1

Adhesions (small bowel)
Hernias (small bowel)
Malignancy (large bowel)

Question 2

What is the presentation of bowel obstruction? (4)

Answer 2

Green bilious vomit
Abdominal distension
Diffuse abdominal pain
Absolute constipation and lack of flatulance

Question 3

What are the upper limits for normal bowel diameter in the small bowel, colon and caecum?

Answer 3

Small bowel up to 3cm
Colon up to 6cm
Caecum up to 9cm

Question 4

What is the difference between valvulae coniventes and haustra and where are they both found?

Answer 4

VC extends full width of bowel, Haustra do not

VC in small bowel
Haustra in large bowel

Question 5

What are the common abnormalities seen in bowel obstruction and what blood tests can you do to discover these (3)

Answer 5

Electrolyte disturbances (U+E)

Metabolic alkalosis due to vomiting (VBG)

Bowel Ischaemia (VBG)

Question 6

What is the initial management of bowel obstruction? (3)

Answer 6

“Drip and suck”

Nil by mouth

IV fluids

NG tube with free drainage

Question 7

What is the initial scan done in a bowel obstruction and what scan confirms the diagnosis

Answer 7

AXR initially

CT abdo confirms diagnosis