From the Guidelines
Mesenteric ischemia requires prompt diagnosis and treatment to reduce high mortality rates, and the most appropriate initial imaging evaluation is CTA of the abdomen and pelvis, as recommended by the American College of Radiology Appropriateness Criteria 1.
Diagnosis and Treatment
Mesenteric ischemia is a serious condition characterized by reduced blood flow to the intestines, potentially leading to tissue damage and death. The underlying pathophysiology involves either arterial occlusion (embolism or thrombosis), venous thrombosis, or non-occlusive causes like low cardiac output states. Risk factors include atherosclerosis, cardiac arrhythmias, hypercoagulable states, and recent major cardiovascular surgery.
- Key considerations in diagnosis include:
- Clinical presentation: abdominal pain, nausea, vomiting, and bloody stools
- Laboratory tests: complete blood count, electrolyte panel, and liver function tests
- Imaging studies: CTA of the abdomen and pelvis, as recommended by the American College of Radiology Appropriateness Criteria 1
Management
Treatment depends on the cause and severity but typically involves restoring blood flow through surgery or endovascular procedures.
- For acute mesenteric ischemia, immediate surgical intervention is often necessary, including:
- Embolectomy
- Bypass grafting
- Resection of necrotic bowel
- Anticoagulation with heparin (initial bolus of 5,000-10,000 units followed by continuous infusion) should be started immediately upon diagnosis, as recommended by the World Society of Emergency Surgery 1.
- Broad-spectrum antibiotics (such as piperacillin-tazobactam 3.375g IV every 6 hours or meropenem 1g IV every 8 hours) are recommended to prevent bacterial translocation.
- Fluid resuscitation and correction of electrolyte imbalances are crucial supportive measures.
Chronic Mesenteric Ischemia
For chronic mesenteric ischemia, endovascular stenting or surgical revascularization may be performed electively.
- The goal of treatment is to restore blood flow to the affected area and prevent further ischemia.
- Treatment options include:
- Endovascular stenting
- Surgical revascularization
- Medical management: antiplatelet therapy, statins, and lifestyle modifications. Early recognition and treatment of mesenteric ischemia are critical to reducing mortality rates, which can range from 30% to 90% in acute settings 1.
From the Research
Definition and Classification of Mesenteric Ischemia
- Mesenteric ischemia is a rare, frequently misdiagnosed, serious condition that carries with it a high rate of morbidity and mortality 2.
- It is classified as either acute or chronic, with acute mesenteric ischemia being a life-threatening emergency 3.
- The most common causes of acute mesenteric ischemia are arterial embolism, arterial thrombosis, nonocclusive mesenteric ischemia, and mesenteric venous thrombosis 3.
Risk Factors and Presentation
- Mesenteric ischemia is associated with a variety of risk factors including older age, cardiovascular disease, hypercoagulable state, and end-stage renal disease 2.
- The presentation depends on the underlying pathophysiology, with arterial embolic disease presenting with sudden, severe pain, and other forms presenting with vague symptoms such as generalized abdominal pain, weight loss, vomiting, and diarrhea 2.
Diagnosis and Imaging
- Laboratory testing can suggest the disease with leukocytosis and elevated lactate, but normal values should not be used to exclude the diagnosis 2.
- The imaging modality of choice is triple phase computed tomography with non-contrast, arterial, and delayed phases 2.
- Biphasic contrast-enhanced computerized tomography is also a diagnostic tool of choice for the detection of arterial or venous occlusion 4.
Treatment and Management
- The initial emergency department management includes 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 is necessary for definitive treatment 2.
- Endovascular therapy has become an important alternative, especially in patients with acute thrombotic superior mesenteric artery occlusion 5, 6.
- Laparotomy is needed to evaluate the extent and severity of visceral organ ischemia, which is treated according to the principles of damage control surgery 5, 6.