Long term mild hypoxia, heart, brain and other oxygen consuming organs function will gradually decline. Severe hypoxia, will occur "myocardial infarction", "cerebral infarction", not timely oxygen first aid, will cause sudden death. Therefore, the long-term use of pulse oxygen detection in patients with cardio cerebrovascular disease can effectively prevent the occurrence of risk. If there is hypoxia, the first time oxygen supplement can greatly reduce the chance of disease attack. People with respiratory diseases (asthma, tracheitis, chronic bronchitis, cor pulmonale, COPD...) On the one hand, dyspnea will lead to insufficient oxygen intake, on the other hand, the persistence of asthma will also block the small branch organs, making it difficult to exchange gas, leading to hypoxia, causing varying degrees of damage to the heart, lung, brain and even kidney. Therefore, the blood oxygen content is detected by pulse oximetry, which greatly reduces the incidence rate of respiratory tract. Elderly people over 60 years old have physiological aging of heart and lung organs, insufficient oxygen intake and poor oxygen supply. The human body relies on blood to transmit oxygen. If there is less blood, there will be less oxygen naturally. With less oxygen, the physical condition will naturally decline. Therefore, the elderly should use pulse oxygen to detect the blood oxygen content every day. Once the blood oxygen is lower than the warning level, they need to supplement oxygen as soon as possible. The brain oxygen consumption of people who work more than 12 hours a day increases, and the oxygen supply can not meet the consumption. The brain oxygen consumption accounts for 20% of the total body oxygen consumption. With the transition of mental work, the brain oxygen consumption is bound to rise. But the human body can take in limited oxygen, consume more, take in less. In addition to causing dizziness, fatigue, poor memory, slow reflection and other problems, it will also cause serious damage to the brain and myocardium. Even death from overwork. Therefore, people who study or work 12 hours a day must use pulse blood oxygen to detect the blood oxygen content every day, and constantly monitor the blood oxygen health, so as to ensure the heart and brain health. Blood oxygen monitoring in extreme sports and high altitude hypoxia environment is helpful to understand the blood circulation of athletes after a large amount of exercise, so as to guide the formulation of the amount of exercise. The reporter needs to carry out blood oxygen detection, through the monitoring of blood oxygen, we can find out the problem of blood oxygen carrying or supplying in advance, so as to avoid cyanosis caused by high mountain reflection, which is harmful to the body. Long term alcoholics need three units of oxygen for each unit of alcohol completely decomposed into water and carbon dioxide. Therefore, hypoxia is one of the important manifestations of drunkenness. However, the long-term alcoholics have developed a certain tolerance to alcohol and hypoxia, and can't be detected when they are slightly drunk. Therefore, carry a blood oxygen meter with you to know the physical condition and degree of drunkenness of alcoholics in time, so as to avoid the occurrence of alcoholism.