Synopsis
Recognise colonic hypoperfusion early, distinguish transient mucosal disease from gangrene and acute mesenteric ischaemia, and coordinate supportive, endoscopic and surgical management according to severity.
- Ischaemic colitis usually presents with sudden cramping abdominal pain followed within hours by rectal blood or bloody diarrhoea after a low-flow or vascular insult.
- The left colon and watershed zones are frequently affected, but isolated right-colon involvement carries greater severity and should lower the threshold for urgent surgical review.
- Risk factors include older age, atherosclerosis, heart failure, hypotension, dehydration, recent major surgery, dialysis, thrombophilia and vasoconstricting or constipating medicines.
Key red flags
Right abdominal pain, little or no bleeding, kidney failure or shock and CT involvement of the ascending colon predicts a worse course and can overlap acute mesenteric ischaemia.
Investigation priorities
Map colonic distribution, grade mural injury and detect perforation, obstruction, malignancy or another cause of acute colitis.
Management branches
Acute pain and rectal blood suggest ischaemic colitis.
- Perform ABCDE, establish onset and pain-before-blood sequence, seek shock or vascular triggers and review cardiac, surgical, dialysis and medicine history.
- Examine repeatedly for focal versus generalised tenderness, distension and perfusion, sending bloods, lactate and stool tests without using normal results to dismiss the diagnosis.
Key medicines
Intravenous crystalloidGive cautious reassessed boluses under the current resuscitation protocol, then replace ongoing deficits according to perfusion, cardiac reserve, renal function and urine output.
Broad-spectrum antibioticFor moderate, severe or surgically threatened disease, use the locally approved intravenous colonic-sepsis regimen and review daily against cultures, source control and recovery.