Bowel Obstruction

Question 1

Define bowel obstruction

Answer 1

Mechanical blockage of the bowel - structural pathology physically blocks the passage of intestinal contents

Question 2

What does bowel obstruction lead to?

Answer 2

Gross dilation of proximal limb
Increased peristalsis of bowel
Secretion of large volumes of electrolyte-rich fluid into bowel

Question 3

Common causes of bowel obstruction

Answer 3

Small bowel
- adhesions
- herniae
Large bowel
- malignancy
- diverticular disease
- volvus

Question 4

Clinical features of bowel obstruction

Answer 4

Abdominal pain - colicky
Vomiting - gastric contents, bilous then faeculent
Abdominal distention
Absolute constipation

Question 5

Bowel obstruction investigations

Answer 5

Bloods - FBC, CRP, U+Es, LFTs and G&S
Venous blood gas - ischaemia (high lactate)
CT scan with IV contract

Question 6

Findings of bowel obstruction on plain abdominal radiograph

Answer 6

Small bowel
- dilated bowel > 3cm
- central abdominal location
- valvulae conniventes visible
Large bowel
- dilated bowel > 6cm
- peripheral location
- haustral lines visible

Question 7

Conservative management of bowel obstruction

Answer 7

NBM and insert nasogastric tube
Start IV fluids - correct electrolyte balance
Urinary catheter and fluid balance
Analgesia

Question 8

Surgical intervention indicated in bowel obstruction patients with

Answer 8

Suspicion of intestinal ischaemia or closed loop bowel obstruction
Small bowel obstruction in patient with virgin abdomen
Cause that requires surgical correction
Patient fails to improve with conservative measures

Question 9

Complications of bowel obstruction

Answer 9

Bowel ischaemia
Bowel perforation -> peritonitis
Dehydration and renal impairment