Bowel Infarction

Question 1

What is infarction?

Answer 1

Tissue necrosis due to interference with the blood supply

Question 2

What are the main causes of bowel infarction?

Answer 2

• Strangulating bowel obstruction
• Occlusion of mesenteric artery by embolus
• Occlusion of mesenteric artery by thrombus
• Occlusion of mesenteric artery by neighbouring aortic dissection
• Compression of mesenteric veins
• Occlusion of mesenteric veins by thrombus
• Vasculitis
• Hypo-perfusion due to low CO

Question 3

What are the different locations a thromboemboli can form to go onto occlude the mesenteric artery?

Answer 3

• In the left atrium during AF
• Mural thrombus secondary to MI
• Vegetation on a heart valve in infective endocarditis
• Rupture of atherosclerotic plaque in the aorta

Question 4

What causes intestinal angina?

Answer 4

• Also known as Chronic Mesenteric Ischaemia
• Caused by gradual onset less severe interference with the blood supply
• Sees severe, colicky intermittent abdominal pain, fear of eating and hence rapid loss of weight

Question 5

What are the clinical features of bowel infarction?

Answer 5

• Acute colicky pain
• Rectal bleeding
• Shock

=> May produce similar signs to peritonitis

Question 6

What is the management of bowel infarction?

Answer 6

• IV fluids
• Borad spectrum antibiotics
• Urgent laparotomy
• Revascularisation by embolectomy or bypass

Question 7

What 3 main conditions come under ischaemia of the lower GI tract?

Answer 7

• Acute mesenteric ischaemia
• Chronic mesenteric ischaemia
• Ischaemic colitis

Question 8

What are the common risk factors of all conditions that come under ischaemia of the lower GI tract?

Answer 8

• Increasing age
• AF
• Other embolic causes: IE, malignancy
• CVD risk factors: smoking, diabetes, hypertension
• Cocaine use

Question 9

What are the common features of Bowel ischaemia?

Answer 9

• Abdominal pain (varies in nature depending on what type of bowel ischaemia)
• Rectal bleeding
• Diarrhoea
• Fever
• Bloods show raised WBC and lactic acidosis

Question 10

What are the differences between Mesenteric Ischaemia and Ischaemic Colitis?

Answer 10

• Mesenteric Ischaemia typically affects the small bowel, Ischaemic Colitis affects the large bowel
• Mesenteric Ischaemia typically has embolic cause where as Ischaemic Colitis is multifactorial
• Mesenteric Ischaemia presents with a sudden onset of severe symptoms where as Ischaemic Colitis presents less severe, BUT WITH BLOODY DIARRHOEA

Question 11

What is the investigation of choice to diagnose bowel ischaemia?

Answer 11

CT

Question 12

What is the management of Acute Mesenteric Ischaemia?

Answer 12

Urgent surgery

Question 13

What region is most commonly affected by Ischaemic Colitis?

Answer 13

Splenic Flexure

Question 14

What is the investigation to identify Ischaemic Colitis and its management?

Answer 14

=> AXR
Thumbprinting

=> Management:
- Largely supportive