Diagnosis is made with blood rheology tests. The examination includes blood rheology examination limb flow diagram renal blood flow renal blood flow (RPF) ventilation to perfusion ratio. It is necessary to identify the increase in resistance caused by various factors and to identify whether it is pathological or not. It should be promptly examined in the surgery of a regular hospital, as well as other diseases to identify. Temperature: The viscosity of the blood increases with decreasing temperature. The surface temperature of the body is lower than the deep temperature, so the viscosity of the blood increases as it flows through the surface portion of the body. If the fingers are immersed in ice water, the local blood viscosity can increase twofold. The increase of blood flow resistance is influenced by the viscosity of blood, while the increase of blood viscosity is manifested by the increase of blood flow resistance, slowing down the flow, especially on small arteries and capillaries and microcirculation, resulting in the reduction of blood perfusion to tissues and producing symptoms of ischemia and hypoxia. Such as headache, vertigo, neck strength, tinnitus, visual disturbance, numbness and swelling of the extremities, and then may produce dysfunction of the heart, brain, kidneys and other organs. Early manifestations: 1. dizziness in the morning, awake at night; 2. sleepiness after lunch; 3. shortness of breath while squatting; 4. paroxysmal blurring of vision; 5. during the blood test, the needle tip is often blocked and the blood is quickly clotted in the syringe, and the blood viscosity is “++++” or higher when the blood rheology is measured, and the other indices are also significantly higher. Blood viscosity: It is one of the factors that determine the resistance to blood flow. The viscosity of whole blood is 4-5 times higher than that of water. Erythrocyte specific volume Generally speaking, the erythrocyte specific volume is the most important factor in determining the viscosity of blood. The larger the erythrocyte volume, the higher the viscosity of blood. Vascular caliber: When blood flows in thicker blood vessels, the caliber of the blood vessel does not affect the blood viscosity. However, when blood flows in micro-arteries less than 0.2-0.3 mm in diameter, blood viscosity becomes lower as the vessel caliber becomes smaller, as long as the cut rate is high enough. The reason for this phenomenon is not fully understood, but there are clear benefits to the organism. Without this response, the resistance of blood flow in small vessels would be much higher.