Intestinal Ischaemia

Question 1

ESSENCE

Answer 1

Mesenteric ischaemia caused by lack of blood flow through mesenteric vessels supplying intestines, resulting in intestinal ischaemia

Question 2

CLASSIFICATION

Answer 2

Acute or chronic

Question 3

ANATOMY

Blood vessels of gut

Answer 3

• Branches of abdominal aorta
  
  • Coeliac artery supplies foregut
  • Superior mesenteric artery supplies midgut
  • Inferior mesenteric artery supplies hindgut

Question 4

ANATOMY

Foregut includes

Answer 4

• Stomach and part of duodenum, biliary system, liver, pancreas and spleen

Question 5

ANATOMY

Midgut includes

Answer 5

Distal part of duodenum to first third transverse colon

Question 6

ANATOMY

Hindgut includes

Answer 6

Second two thirds transverse colon to rectum

Question 7

What is chronic mesenertic ischaemia also called

Answer 7

Intestinal angina

Question 8

AETIOLOGY

Chronic main cause

Answer 8

• Narrowing of mesenteric vessels by atherosclerosis

Question 9

AETIOLOGY

Risk factors chronic

Answer 9

• Age
• FH
• Smoking
• Diabetes
• Hypertension
• Raised cholesterol

Question 10

CLINICAL FEATURES

Presentation chronic

Answer 10

• Classic triad of
  
  • Central colicky abdominal pain after eating (starting around 30 mins after and lasting 1-2 hours)
  • Weight loss
  • Abdominal bruit

Question 11

INVESTIGATION

First choice

Answer 11

CT angiography - diagnosis and first choice

Question 12

MANAGEMENT

General principles chronic

Answer 12

• Reduce modifiable risk factors
• Secondary prevention
• Revascularisation

Question 13

MANAGEMENT

Secondary prevention chronic

Answer 13

• Statins and antiplatelet medications

Question 14

MANAGEMENT

Revasculaturisation options chronic

Answer 14

• Endovascular procedures first line (ie percutaneous mesenteric artery stenting)
• Open surgery (eg endarectomy, re-implantation or bypass grafting)

Question 15

AETIOLOGY

Main cause acute

Answer 15

• Rapid blockage in blood flow due to thrombus or embolus

Question 16

AETIOLOGY

Risk factors acute

Answer 16

• Key risk factor is atrial fibulation
• Same as for acute

Question 17

CLINICAL FEATURES

Presentation acute

Answer 17

• Acute, non-specific abdominal pain
  
  • Dispraportionate to examination findings
• Can go on to develop shock, peritonitis and sepsis
• Over time ischaemia results in necrosis of bowel tissue and perforation

Question 18

INVESTIGATIONS

How are blood gases changes in ischaemia

Answer 18

• Metabolic acidosis and raised lactate

Question 19

MANAGEMENT

General principles acute

Answer 19

• Need surgery to
  
  • Remove necrotic bowel
  • Remove or bypass thrombus in blood vessel (open surgery or endovascular procedures may be used)