Increased hemoglobin means increased hemoglobin concentration, which is 120-160 g/L for adult males and 110-150 g/L for adult females, and is commonly seen in two situations: the first is when the body is severely dehydrated, resulting in a relative increase in hemoglobin, such as severe diarrhea and vomiting, which causes a relative increase in hemoglobin concentration. Relatively high hemoglobin concentration. The second condition, high hemoglobin concentration caused by absolute increase in the number of red blood cells, such as chronic obstructive pulmonary disease, congenital cyanotic heart disease and residents of highland areas, is caused by long-term hypoxia, resulting in high hemoglobin concentration due to the increase in the reactivity of red blood cells. In addition, clinically high hemoglobin concentration caused by myeloproliferative disorders, such as true erythrocytosis and primary hemoglobin, can be seen. The high hemoglobin concentration is caused by an abnormally high number of red blood cells.