see: [Dunn - Mesenteric ischaemia](x-devonthink-item://B37312F3-20F1-4B43-9A2F-06F9F5FD94E9), [Rosen - Acute mesenteric ischemia](x-devonthink-item://FF7B8689-9B69-44CD-B8D6-F751D37D7073?page=5) **causes** - arterial obstruction 90% - embolism - thrombosis - venous ischaemia 10% - usually secondary to other pathology: - hyperviscosity - pro-coagulant state - pancreatitis - diverticulitis - nephrotic syndrome - abdominal infection - *prior VTE in 50% of these* - heart failure - haemodialysis **Risk factors** - cardiovascular disease (IHD, PVD, diabetes, HTN) - [[Atrial fibrillation]] → source of systemic embolism - [[Endocarditis]] - transmural MI - cardiomyopathy - age > 50 risk for mesenteric arterial thrombosis: - atherosclerosis (advanced age, HTN, diabetes, tobacco use) **Types** Acute - superior mesenteric artery occlusion: - embolus - thrombus - [[Aortic dissection]] - superior mesenteric vein occlusion - [[Bowel obstruction|small bowel obstruction]] - non-occlusive mesenteric ischaemia (eg shocked state) - small vessel involvement - vasculitis - chemotherapy - radiation enteritis subacute / chronic - atherosclerotic stenosis of superior mesenteric artery (eg mesenteric angina) - chronic radiation enteritis ## pneumatosis intestinalis - presence of extraluminal gas in the submucosal and/or subserosal layers of bowel wall - 85% of cases from mesenteric ischaemia - *poor prognosis when present* # management - ceftriaxone + metronidazole - gen surg + vascular (endovascular vs open resection of ischaemia) - if mesenteric venous thrombosis → heparin