Blood leaving the veins is the clinical manifestation of crush syndrome. Crush syndrome is a series of pathological changes in the body caused after a person is crushed by a stone and earth, especially a muscular limb is crushed for more than one hour (e.g. thigh). Due to damage to the skin and flesh, blood leaving the veins, stasis of blood, stagnation of qi and blood, and occlusion of meridians, localized pain, swelling of the limb, indentation and hardening of the skin, subcutaneous stasis of blood, and increased skin tension. What are the examination methods for extrusion syndrome? 1.Urinal examination Early urine volume is low, specific gravity is above 1.020, urine sodium is less than 60mmol/L, urea is more than 0.333mmol/L. In the oliguric or anuric phase, urine volume is low or urine is closed, urine specific gravity is low, fixed at about 1.010, urine myoglobin is positive, urine contains protein, red blood cells or see tube type. Urinary sodium is more than 60mmol/L, urea is less than 0.1665mmol/L, the ratio of urinary urea nitrogen to blood urea nitrogen is less than 10:1, the ratio of urinary creatinine to blood creatinine is less than 20:1. urinary specific gravity is still low until the polyuria period and recovery period, urinary routine can gradually return to normal. 2. Hematocrit, red blood cell count and red blood cell pressure to estimate the degree of blood loss, loss of plasma components, anemia or water retention during oliguria. Platelets and clotting time can indicate abnormalities in coagulation and fibrinolytic mechanism of the body. 4.Glutamic oxalacetic transaminase (GOT), creatine phosphokinase (CPK) Determination of muscle ischemic necrosis released by the enzyme, can understand the degree of muscle necrosis and its pattern of growth and decline. 5.Blood potassium, blood magnesium, blood myoglobin measurement Can understand the severity of the patient’s condition. Due to the damage of flesh and skin, blood leaving the veins and blood stagnation, stagnation of qi and blood, meridian occlusion, local pain, limb swelling, skin indentation, hardening, subcutaneous bruising, increased skin tension, blister formation around the compressed skin, when checking the blood circulation status of the limb, it is worth noting that if the distal pulse of the limb does not weaken, the muscle tissue is still at risk of ischemic necrosis, pay attention to check the muscle and Nerve function, active activity and passive pulling can cause pain, which is helpful in determining the muscle groups involved in the fascial interval zone.