Bowel ischaemia Flashcards
What is ischaemic colitis?
Ischaemia of colonic arterial supply causing colon inflammation due to hypoperfusion
What are causes of ischaemia within the IMA (inferior mesenteric artery) to cause ischaemic colitis?
Thrombosis
Emboli
Decreased cardiac output and arrhythmias/ history of AF
COCP
What are the most commonly affected sites in ischaemic colitis?
Watershed areas (regions in colon between 2 major arteries):
Splenic flexure
Sigmoid colon
Caecum
What are symptoms of ischemic colitis?
LLQ pain and bright bloody stool
May have signs of hypovolemic shock
How do you diagnose ischaemic colitis?
Gold standard = Colonoscopy and biopsy
(only do this after patient recovered to prevent strictures forming)
Rule out other causes eg. stool sample for H pylori
What is treatment for ischaemic colitis?
If symptomatic: IV fluid and prophylactic antibiotics
If gangrenous (infarcted colon): only surgery
What are complications of ischaemic colitis?
Perforation (causing SBP)
Strictures ( causing obstruction)
What is mesenteric ischaemia?
Ischemia of the small intestine
Can be acute or chronic
What is AMI and how is it described?
Acute mesenteric ischaemia, acute attack.
“Abdominal MI”
What is CMI and how is it described?
Chronic mesenteric ischaemia, longer lasting over months
“Abdominal angina”
What are causes of mesenteric ischaemia?
SMA (superior mesenteric artery is hypoperfused):
Thrombosis
Emboli (often due to AF)
What are the triad of symptoms for mesenteric ischaemia?
Central / right iliac fossa acute severe abdominal pain
No abdominal signs on exam (guarding, rebound tenderness)
Rapid hypovolemic shock
How is mesenteric ischaemia diagnosed?
CT angiogram
FBC and ABG shows persistent metabolic acidosis
Why is there metabolic acidosis in mesenteric ischaemia?
There is an overgrowth of bacterial flora which release D-lactate into circulation, lowering pH and causing metabolic acidosis
how is mesenteric ischaemia treated?
Fluid replacement
Antibiotics
IV heparin (prevents clots forming/ getting larger)
Surgery for any infarcted bowel
