Small and large bowel obstruction

Question 1

What is the definition of a bowel obstruction?

Answer 1

Mechanical or functional obstruction of the intestines that prevents normal movement of products of digestion

Question 2

Bowel obstructions make up what % of all acute abdominal diseases?

Answer 2

5% of all acute abdomen diseases

Question 3

What is the pathology of bowel obstruction?

Answer 3

• Mechanical: Physical blockage causes dilatation of proximal bowel due to ↑ secretions and swallowed air
• Bowel dilatation causes fluid accumulation
• Increase in intraluminal pressure proximally = vomiting
Functional: occurs with a paralytic ileus
Often seen after abdominal operations or opiate treatment
Nerves and muscles of the intestine are damaged = intesttinal pseudo obstruction

Question 4

What are the risk factors/aetiology of bowel obstruction?

Answer 4

• Postoperative adhesions
• Malignancy (ovarian and colonic)
• Crohns disease
• Hernias
• Gallstones
• Volvulus
• Diverticular disease
• Intussusception – one section of intestine collapses into the other

Question 5

What are the signs/symptoms of bowel obstruction?

Answer 5

• Intermittent crampy/colicky abdominal pain
• Nausea/bilious vomiting – small bowel, more profuse if upper gut obstruction
• Diarrhoea – earlier symptom, partial obstruction
• Constipation – later symptom, complete obstruction
• Decreased appetite
• Abdominal swelling
• Lack of passing wind
• Pyrexia - strangulation
• Tachycardia - strangulation

Question 6

What diseases present similarly to bowel obstruction?

Answer 6

• Hepatic disease

* Biliary disease

Question 7

What investigations are conducted for suspected bowel obstruction?

Answer 7

• Blood urea nitrogen (BUN) level
• Creatinine
• FBC, U&E’s
• Lactate dehydrogenase
• Urinalysis
• X-ray (with/without contrast)
• CT – if tachycardic, fever, abdo pain or leukocytosis
• US
• Colonoscopy

Question 8

What are the surgical treatments for bowel obstruction?

Answer 8

• Nasogastric intubation – remove fluid/gas
• Malignancy: removal/stents
• Colostomy – critically ill patients
• Sigmoid volvulus – insertion of flexible sigmoidoscope/rectal tube to unkink the bowel
• Stricturoplasty
• Bowel resection
• CT guided drainage – if abscess present
• Hernia repair

Question 9

What are the pharmacological treatments for bowel obstruction?

Answer 9

• Chemotherapy/radiation
• Steroids – IBD
• Fluids
• Anti-emetics
• Antibiotics
• Analgesia

Question 10

What are the non pharmacological treatments for bowel obstruction?

Answer 10

None as MEDICAL EMERGENCY