Makindo Medical Notes

🩸 Ischaemic Colitis is the most common form of intestinal ischaemia. It usually resolves with supportive management, but careful observation is vital as it can progress to gangrene, peritonitis, or stricture formation. It is most commonly seen in older adults (60s–70s) with vascular risk factors.

📖 About

• Ischaemia of the colon due to impaired blood supply.
• Ranges from superficial mucosal injury → full-thickness necrosis.
• Blood supply: superior mesenteric artery (SMA) & inferior mesenteric artery (IMA).
• Watershed areas (esp. splenic flexure & rectosigmoid) are most vulnerable.

⚠️ Aetiology

• Occlusive causes: thrombosis, embolism, vasculitis.
• Non-occlusive causes: low-flow states, vasospasm (shock, hypotension, cardiac failure).
• Risk factors: atrial fibrillation, atherosclerosis, previous MI, recent surgery (esp. aortic aneurysm repair).
• Pathology: mucosal ischaemia → inflammation → necrosis → perforation if severe.

🔎 Key features: Bloody diarrhoea, left-sided abdominal pain, raised lactate/WCC in elderly patients.

🩺 Clinical Presentation

• Sudden crampy abdominal pain (often left-sided).
• Bloody diarrhoea ± vomiting.
• History of hypotension (MI, shock, post-surgery).
• Abdominal distension, fever, tachycardia.
• Localised peritonism on exam.
• Subacute cases: colonic “claudication” with post-prandial pain and diarrhoea.

⚡ Complications

• Acute: Sepsis, perforation, peritonitis, toxic megacolon.
• Chronic: Stricture formation (classically at splenic flexure).

🔬 Investigations

• Bloods: ↑ WCC, CRP, lactate, LDH; metabolic acidosis on ABG.
• AXR: Nonspecific; may show “thumbprinting” (submucosal oedema/haemorrhage).
• CXR: Free air under diaphragm if perforation.
• CT Abdomen (with contrast): Colonic wall thickening, fat stranding, pneumatosis, or portal venous gas in advanced cases.
• Colonoscopy: Gold standard (done without prep) – shows mucosal oedema, erythema, ulceration, and necrosis if advanced.
• Stool cultures: To exclude infective colitis if uncertain.

💊 Management

• 🏥 Admit, resuscitate, and monitor closely (ABC approach).
• Supportive: IV fluids, oxygen, NBM + NG tube, analgesia.
• Antibiotics: Broad-spectrum IV cover for bacterial translocation.
• Anticoagulation: Consider UFH if thrombotic cause suspected.
• Surgery: For peritonitis, gangrene, perforation, or severe ischaemia. → Laparotomy + resection ± stoma (primary anastomosis usually contraindicated). Mortality remains high in advanced disease.

📝 Summary

Ischaemic colitis is common in elderly patients with vascular risk factors. Most cases resolve with supportive care, but progression to full-thickness necrosis carries high mortality. The splenic flexure (Griffith’s point) and rectosigmoid junction (Sudeck’s point) are classic watershed sites. 🚨