A clinical approach to acute mesenteric ischemia

Abstract

Purpose of review To summarize current evidence on acute mesenteric ischemia (AMI) in critically ill patients, addressing pathophysiology, definition, diagnosis and management. Recent findings A few recent studies showed that a multidiscipliary approach in specialized centers can improve the outcome of AMI. Such approach incorporates current knowledge in pathophysiology, early diagnosis with triphasic computed tomography (CT)-angiography, immediate endovascular or surgical restoration of mesenteric perfusion, and damage control surgery if transmural bowel infarction is present. No specific biomarkers are available to detect early mucosal injury in clinical setting. Nonocclusive mesenteric ischemia presents particular challenges, as the diagnosis based on CT-findings as well as vascular management is more difficult; some recent evidence suggests a possible role of potentially treatable stenosis of superior mesenteric artery and beneficial effect of vasodilator therapy (intravenous or local intra-arterial). Medical management of AMI is supportive, including aiming of euvolemia and balanced systemic oxygen demand/delivery. Enteral nutrition should be withheld during ongoing ischemia-reperfusion injury and be started at low rate after revascularization of the (remaining) bowel is convincingly achieved. Summary Clinical suspicion leading to tri-phasic CT-angiography is a mainstay for diagnosis. Diagnosis of nonocclusive mesenteric ischemia and early intestinal injury remains challenging. Multidisciplinary team effort may improve the outcome of AMI.

Non-occlusive mesenteric ischemia: Diagnostic challenges and perspectives in the era of artificial intelligence

“…The pathophysiological mechanical concept of AMI relies on an imbalance between oxygen supply and demand of the intestinal tissues. Ischemic lesions first begin to appear in the intestinal mucosa and subsequently may progress to irreversible transmural necrosis[ 22 , 23 ]. Complications include intestinal perforation, peritonitis, bacteriemia due to rupture of the gut barrier, inflammation leading to further non-mesenteric organ dysfunction, and shock.…”

“…Hence, given the numerous pitfalls of the current diagnostic approach for the diagnosis of NOMI, a high index of suspicion is required in populations at risk, such as post cardiac or aortic surgery, hemodialyzed patients, and critically ill patients[ 23 , 73 ]. Research is encouraged to identify or validate new biomarkers and imagery tools and increase knowledge on the pathophysiological understanding of NOMI genesis, especially in critically ill patients[ 36 ].…”

Acute mesenteric ischemia: updated guidelines of the World Society of Emergency Surgery

“…Recent published evidence suggests that treatment of occlusive AMI in “intestine stroke centers” using a multidisciplinary approach improves outcomes [ 142 , 143 ]. Improving survival rates can be obtained if mesenteric ischemia is diagnosed and treated early.…”

Intraluminal oxygen mitigates acute mesenteric ischaemia: a systematic review of methods and outcomes in animal studies

“…Diagnosis of AMI is challenging, as the presenting symptoms and signs are non‐specific, and there are no perfect biomarkers 8 . CT angiography is valuable, and identifies vessel occlusion or local complications requiring surgical intervention 9 . Treatment depends on the aetiology, but common principles include restoration of blood supply and surgical control of ischaemic complications.…”