Acute Limb Ischemia.

Acute limb ischemia (ALI) is a rapid decrease in lower limb blood flow due to acute occlusion of peripheral artery or bypass graft, and in ALI not only limbs but also life prognosis will be poor unless quick and appropriate treatment is given. The etiology is broadly divided into embolism and thrombosis with various comorbidities. The symptoms of ALI are abrupt with pain, numbness, and coldness of lower limb, and paresthesia, contracture, and irreversible purpura will appear with the exacerbation of ischemia. Severity and treatment strategy should be determined based on physical findings and image findings. Considering life prognosis, limb amputation should be done without hesitation when the limb was diagnosed as irreversible. ALI can be treated by means of open surgical revascularization, endovascular, or hybrid approach with rapid systemic administration of heparin. In any cases, evaluating the lesions by intraoperative angiography and appropriate additional treatment are important. ALI is a serious disease requiring urgent treatment, and it is essential to promptly perform the best initial treatment that can be performed at each facility. (This is a translation of Jpn J Vasc Surg 2018; 27: 109-114.).