Pale blue face or black face, mostly for real cold evidence, severe pain. Cold is the main attraction, and its nature is Yin condensation, cold condensation and Qi stagnation, menstrual vessels are constricted, blood flow is not smooth, stasis color is exposed, so the blue color is seen. Severe pain, resulting in constriction of the meridians and poor blood flow, can also be seen as cyanosis. The following diseases are also common causes of cyanosis: 1. Pregnancy fever Pregnancy fever is the equivalent of Western medicine’s premature miscarriage and stillbirth in the middle and late stages of pregnancy. The fetal death is one of the common clinical diseases and should be treated promptly after diagnosis. The stillborn fetus stays in the uterine cavity for too long and is prone to coagulation mechanism disorders, leading to diffuse intravascular coagulation, which can endanger the life of the pregnant woman. 2, acute left heart failure in the elderly Acute left heart failure is a clinical syndrome caused by a significant decrease in myocardial contractility and/or a significant increase in cardiac load within a short period of time, resulting in a sharp decrease in cardiac blood output and a sharp increase in pulmonary circulation pressure. The clinical manifestations are acute pulmonary edema, severe dyspnea, cyanosis, coughing pink foamy sputum, critical condition, cardiogenic shock, coma and death can occur rapidly. 3. Non-dependent substances with dependence Non-dependent substances with dependence refers to alcohol dependence, alcohol intoxication opioids, sedative-anesthetics narcotics, stimulants, and application of other psychoactive substances (pesticides carbon monoxide, heavy metals, and other substances poisoning) with associated mental disorders, followed by psychological and physiological symptoms, changes in behavior or reactions (nausea, vomiting, palpitations, inattention, pain dulling, etc.), and at the same time, psychological and physiological symptoms. pain dullness, etc.), while causing a significant decrease in mental activity or a significant decrease in social function. Acute intoxication or withdrawal may result in disorders of consciousness or psychotic states. Chronic intoxication may result in personality changes, amnesia syndrome, and dementia.