Decreased skin temperature is the clinical manifestation of arterial embolism. Arterial embolism is a pathological process in which an embolus is dislodged from the wall of the heart or proximal artery, or enters the artery from outside and is pushed distally by the blood flow, blocking the arterial blood flow and causing ischemia and even necrosis of the limb or internal organs. When peripheral artery embolism occurs, the affected limb has pain, pallor, loss of distal arterial pulsation, coldness, numbness and motor impairment. The onset of the disease is rapid and the limb and even life is threatened after the onset of the disease, so it is important to diagnose the disease early and administer appropriate treatment in a timely manner. The main symptoms are severe pain, numbness, dyskinesia, waxy pale skin, cold skin, decrease in skin temperature by 3-5°C, and loss or weakening of the arterial pulse. Diagnosis of arterial embolism caused by decreased skin temperature: 1.General examination: lipid measurement, electrocardiogram, cardiac function and fundus examination, etc. 2.Non-invasive vascular examination: ultrasonic Doppler flow examination and segmental arterial pressure measurement, electrical impedance volume tracing or photoelectric volume tracing, etc., to understand the blood flow condition of the affected limb. Ultrasound Doppler imaging can show the lumen pattern and blood flow condition. 3.X-ray radiography: Sometimes irregular calcification of the diseased arterial segment and degenerative changes such as osteoporosis in the distal segment of the affected limb can be seen. 4.Arteriography: It can accurately show the location, extent, degree of lesion, side branches and occlusion of the distal arterial trunk, which is important for the selection of surgical methods. Both magnetic resonance angiography (MRA) and digital subtraction angiography (DSA) can achieve the purpose of diagnosis and guiding treatment.