Bowel obstruction

Question 1

What are the symptoms of obstruction?

Answer 1

4 cardinal features;

• Vomitting
  
  • Faecalant vomitting (faecal is caused by fistula)
• Colic
• Constipation (not always absolute)
• Distension

Other;

• Anorexia
• Tinkling bowel sounds

Question 2

What are the differences of small & large bowel obstruction?

Answer 2

• Small bowel
  
  • Ealier vomiting
  • Less distension
  • More pain
  • AXR
    
    • Central gas shadows with valvulae conniventes (cross the lumen)
• Large bowel
  
  • Constant pain
  • AXR
    
    • Peripher gas shadows proximal to blockage (caecum) [not rectum]
    • Haustra do not cross lumen width

Question 3

What is an ileus? And what is the difference between an ileus and mechanical obstruction?

Answer 3

Ilius is the loss of GI motility.

• Only refers to loss of peristalisis (not obstruction generally)

Differenes between ilius and obstruction;

• Ilius has no pain
• Ilius has absent bowels sound

Question 4

What is the definition and differences between simple, closed lopp and strangulated obstructed bowel?

Answer 4

1. Simple
   
   • 1 obstructing point & no vascular compromise
2. Closed-loop
   
   • 2 obstruction points
   • forming loop of grossly distended bowel at risk of perforation
3. Strangulated
   
   • Compromised blood supply
   • Sharper, more constant, localized pain than the central colic of obstruction
   • Peritonism is cardinal sign
   • Fever, inc. WBC and other signs of mesenteric ischaemia

Question 5

What are the typical and rarer causes of obstruction?

Differentiate large & small bowel causes.

Answer 5

1. Constipation (large)
2. Hernias (both)
3. Adhesions (small)
4. Tumours (both)

Others;

• Crohn’s
• Gallstone ileus (small)
• Intussusception (small)
• Diverticular stricture (large)
• Volvulus (SI, caecum, sigmoid, colon..)
• Foreign body (small usually)