Blood sedimentation is the erythrocyte sedimentation rate (ESR), Weil’s method: adult male 0-15mm/h; adult female 0-20mm/h. Weil’s method blood sedimentation value up to 25mm/h is mildly increased; up to 50mm/h is moderately increased; more than 50mm/h is severely increased. The increase of hematocrit is divided into physiological increase and pathological increase. Physiological increase: up to 30mm/h or more in women during menstruation, more than 3 months of pregnancy to 3 weeks after delivery; over 60 years of age (due to gradual increase in plasma fibrinogen content, etc.) Pathological increase: ① Various inflammatory diseases: acute inflammatory diseases of bacterial origin, increased blood sedimentation can be seen in 2 to 3 days of inflammation. In rheumatic fever and chronic inflammatory diseases such as tuberculosis, the blood sedimentation rate increases significantly. (2) Tissue injury and necrosis: Large surgical trauma can cause increased sedimentation; in myocardial infarction, sedimentation is often increased three to four days after onset and lasts one to three weeks; in angina pectoris, sedimentation is normal. (3) Malignant tumor: It is related to tumor tissue necrosis, secondary infection and cachexia. The blood sedimentation of benign tumors is mostly normal, so it is often used as a screening test for malignant tumors, especially those that cannot be detected by non-surface tumors and general X-ray examination. The blood sedimentation of malignant tumor is normalized by surgical resection or complete chemotherapy or radiotherapy, but it is increased when it recurs or metastasizes. Hyperglobulinemia caused by various reasons: subacute infective endocarditis, black fever, systemic lupus erythematosus; relative globulin increase caused by various reasons such as chronic nephritis, liver cirrhosis. In multiple myeloma, macroglobulinemia, plasma cell malignant proliferative disease with increased blood sedimentation. ⑤ Anemia: In anemia with hemoglobin below 90g/L, the hematocrit increases, and the more severe the anemia, the more pronounced the increase in hematocrit. However, it should be noted that in hypochromic anemia, the sinking is slow due to the small size of red blood cells and insufficient amount of hemoglobin; in hereditary spherocytosis and sickle cell anemia, the morphology of red blood cells is not conducive to coincidental aggregation, and the sinking slows down instead. (6) Hypercholesterolemia: increased sedimentation. Slowed sedimentation: less significant and can be due to a significant increase in the number of red blood cells and a severe decrease in fibrinogen content. It is seen in: dehydrated hemoconcentration due to various causes, true erythrocytosis and diffuse intravascular coagulation.