Early diagnosis and timely surgical intervention are the cornerstones of modern treatment and are essential to reduce the high mortality associated with this entity.
- Superior mesenteric artery is most vulnerable
- Embolism from AF or LV thrombus
- Thrombosis in situ
- Venous thrombosis
- Superior mesenteric artery (SMA) is the primary blood supply for the small bowel with some collateral flow from the coeliac arterial system
- This is via the superior and inferior pancreaticoduodenal arteries, as well as from the inferior mesenteric artery
- The SMA is particularly vulnerable because of its relatively large diameter and low takeoff angle from the aorta.
- The majority of emboli lodge 3 to 10 cm distal to the origin of the SMA, thus classically sparing the proximal jejunum and colon
- Acute severe abdominal pain but can be minimal
- Older patients or those on steroids may present atypically
- Some may have acute on chronic ischaemia with food induced abdominal pain
- Peritonism suggests irreversible intestinal ischaemia with bowel necrosis
- FBC: WCC rise. U&E may see AKI
- ABG: Metabolic acidosis with elevated lactate level. Indeed lactic acidosis in a combination of abdominal pain when the patient may not otherwise appear clinically ill should lead to consideration for early CTA.
- ECG : ? AF? MI? LVH
- AXR: only becomes positive when bowel infarction has developed an intestinal perforation manifests as free intraperitoneal air.
- CT/Angiogram Abdomen: irreversible ischaemia (intestinal dilatation and thickness, reduction or absence of visceral enhancement, pneumatosis intestinalis, and portal venous gas) and free intraperitoneal air
- ABC, Oxygen. IV fluids. Correct electrolytes. NBM and NG suction
- Broad-spectrum antibiotics should be administered immediately.
- Unless contraindicated, patients should be anticoagulated with intravenous unfractionacted Heparin
- Prompt laparotomy should be done for patients with overt peritonitis.
- Mesenteric venous thrombosis can often be successfully treated with a continuous infusion of unfractionated Heparin
- Close cooperation between acute care surgeons, radiologists, anesthetists, and the vascular surgeons is essential.