What is the range of pulse oxygen saturation in normal people? Pulse oxygen saturation is the percentage of the capacity of oxygenated hemoglobin bound by oxygen in the blood to the capacity of all binding hemoglobin, that is, the concentration of blood oxygen in the blood. It is an important parameter of the respiratory system. So what is the range of normal pulse oxygen saturation? Let's have a look
What is the range of normal pulse oxygen saturation?
The oxygen saturation of normal human arterial blood is 98% and that of venous blood is 75%. It is generally believed that SpO2 should not be lower than 94% when it is normal, and oxygen supply is insufficient when it is lower than 94%.
Clinical significance: decrease of blood oxygen saturation: it can be seen in hypoxic lung diseases such as emphysema, circulating hypoxia and tissue hypoxia. Elevated: seen in hyperbaric oxygen therapy. Oxygen saturation, the oxygen saturation in your blood, can reflect whether you lack oxygen. Whether oxygen therapy is needed.
Detection method of blood oxygen saturation
Methods: the equipment of pulse oxygen saturation meter, which is specially designed to measure the patient's blood oxygen level. This small instrument is connected to the finger tip or earlobe, and then emits different light colors. For pediatric patients, you can also pin the pulse oximeter on your toes. It can measure blood oxygen saturation and display the reading on a small screen. If the reading is between 96-100%, it means normal.
What about low blood oxygen saturation?
1. Oxygen therapy: the purpose of oxygen therapy is to improve arterial oxygen partial pressure, oxygen saturation and oxygen content, so as to correct hypoxemia, ensure oxygen supply to tissues and alleviate tissue hypoxia.
2. Hyperbaric oxygen chamber treatment
3. Relieving bronchospasm mainly uses phosphodiesterase inhibitors such as aminophylline and dihydroxypropyltheophylline, which can relax airway smooth muscle and inhibit histamine release.
Reasons for low blood oxygen saturation:
1. Check whether the oxygen partial pressure of suction gas is too low. When the oxygen content of inhaled gas is insufficient, it can cause the decrease of blood oxygen saturation. In combination with the medical history, ask whether the patient has been to the plateau above 3000 m, high-altitude flight, rise after diving, and poorly ventilated mines.
2. Whether there is airflow blockage. It is necessary to consider whether there is obstructive ventilation deficiency caused by asthma, COPD, falling back of the root of the tongue, obstruction of foreign bodies in respiratory secretions and other diseases.
3. Whether there is ventilation dysfunction. We should consider whether the patient has severe pneumonia, severe pulmonary tuberculosis, diffuse pulmonary interstitial fibrosis, pulmonary edema, pulmonary embolism and other diseases that affect the ventilation function.
4. What is the quality and quantity of HB transporting oxygen in the blood. The emergence of abnormal substances, such as CO poisoning, nitrite poisoning and abnormal hemoglobin, not only seriously affects the transport of oxygen in the blood, but also seriously affects the release of oxygen.
5. Whether the patient has appropriate colloidal osmotic pressure and blood volume. Proper colloidal osmotic pressure and adequate blood volume are one of the key factors to maintain normal oxygen saturation.
6. What is the patient's cardiac output. To maintain the normal oxygen delivery of organs, there should be enough cardiac output to support it.
7. Microcirculation of tissues and organs. Whether the proper oxygen and can be maintained is also related to the body's metabolism. When the body's metabolism is too large, the oxygen content of venous blood will be significantly reduced, and the shunt pulmonary circulation of venous blood will lead to more serious hypoxia.
8. Utilization of oxygen in surrounding tissues. Tissue cells can only use free oxygen, and the oxygen bound to Hb can only be released for tissue use. The changes of pH and 2,3-DPG affect the dissociation of oxygen from Hb.
9. After excluding all the above factors, don't forget that the decrease of oxygen saturation may be caused by instrument failure.