What is the treatment algorithm for mesenteric ischemia?

From the Guidelines

The treatment algorithm for mesenteric ischemia begins with prompt diagnosis and immediate intervention to restore blood flow and prevent bowel necrosis, with the most recent guidelines from 2022 recommending a multidisciplinary approach based on early diagnosis and individualized treatment 1. Initial management includes:

• Fluid resuscitation with isotonic crystalloids
• Correction of electrolyte abnormalities
• Broad-spectrum antibiotics, such as piperacillin-tazobactam 3.375g IV every 6 hours or meropenem 1g IV every 8 hours
• Anticoagulation with unfractionated heparin, with an initial bolus of 80 units/kg followed by continuous infusion at 18 units/kg/hr, titrated to aPTT of 60-80 seconds Pain control should be addressed with opioid analgesics as needed. For acute arterial occlusion, revascularization is crucial and may be achieved through:
• Endovascular approaches, such as angioplasty, stenting, or thrombolysis
• Open surgical techniques, such as embolectomy, bypass, or endarterectomy In non-occlusive mesenteric ischemia, intra-arterial vasodilators like papaverine (30-60 mg/hr) may be administered. Surgical exploration is necessary when peritoneal signs are present or if clinical deterioration occurs despite medical therapy. During surgery, non-viable bowel is resected, and a second-look laparotomy is often planned within 24-48 hours to reassess bowel viability. Post-intervention care includes continued anticoagulation, nutritional support, and treatment of underlying conditions, as recommended by the most recent guidelines from the American College of Radiology in 2022 1. This aggressive approach is essential because mesenteric ischemia carries high mortality rates due to the rapid progression from ischemia to irreversible bowel necrosis, sepsis, and multi-organ failure if blood flow is not promptly restored, with mortality rates approaching 60% if left untreated 1. The use of endovascular approaches has been associated with a decrease in the amount of bowel resected, lower incidence of concomitant renal or respiratory failure, lower subsequent incidence of short bowel syndrome, and lower mortality, as reported in a study from 2017 1. The World Society of Emergency Surgery also recommends a focused multidisciplinary approach based on early diagnosis and individualized treatment, with the prompt use of CT angiography to establish the diagnosis, evaluation of the potential for revascularization, resection of necrotic intestine, and use of damage control techniques when appropriate 1.

From the Research

Mesenteric Ischemia Treatment Algorithm

The treatment algorithm for mesenteric ischemia involves a multidisciplinary approach, including:

• Initial management in the emergency department (ED) with fluid resuscitation, symptomatic therapy, broad-spectrum antibiotics, and anticoagulation 2
• Emergent consultation with a multidisciplinary team, including diagnostic and interventional radiologists, and cardiovascular and general surgeons 2
• Restoration of perfusion to ischemic bowel and resection of any necrotic intestine 3
• Use of endovascular intervention and surgery as complementary approaches to treat mesenteric ischemia 3, 4
• Consideration of antibiotic use, although the evidence is limited and more studies are needed to determine its effectiveness in improving outcomes 5

Treatment Options

The treatment options for mesenteric ischemia include:

• Endovascular recanalization and stenting for patients with acute and chronic thrombotic superior mesenteric artery (SMA) occlusion 4
• Aspiration embolectomy, thrombolysis, and open surgical embolectomy for embolic SMA occlusion 4
• Endovascular therapy for patients with mesenteric venous thrombosis who do not respond to anticoagulation therapy 4
• Damage-control surgery after intestinal revascularization 4
• Intestinal revascularization to reduce bowel morbidity and mortality in patients with arterial occlusive mesenteric ischemia 4

Diagnostic Approach

The diagnostic approach for mesenteric ischemia includes:

• Laboratory testing, such as leukocytosis and elevated lactate, although normal values should not be used to exclude the diagnosis 2
• Imaging modalities, such as triple phase computed tomography with non-contrast, arterial, and delayed phases 2
• Modern computed tomography (CT) with intravenous contrast enhancement and imaging in the arterial and/or portal venous phase 4