In addition to the invasive test in the hospital, most of the blood oxygen test or pulse oximeter to carry out, and the principle of the oximeter is through the red LED + infrared LED emission of specific wavelengths of light, and then by the device to receive the reflected or projected light, the finger clip type oximeter used by the projected, and smart watches and smart bracelets such as the wrist device, taking into account the transmittance and the watch band The smartwatch and smart bracelet wrist devices, considering the transmittance and strap reasons, naturally not good to use the projected type, so they all use the reflective type.
But there are still differences in the accuracy of the two, we take Apple's Apple Watch as an example, we can see when we look at the parameters, Apple's heart rate monitoring function is over the U.S. FDA certification, but its oxygen saturation monitoring is not certified, and most of the smart wearable devices this function has not been certified by the FDA. This can also be seen in the domestic devices, such as Huawei's Watch GT 3 Pro ECG ECG analysis through the national NMPA Class II medical device certification, but through the certification of the wrist oximeter is almost nothing, even if there is also unrelated to smart wearable devices. You can see the smart wearable device program, to reach the medical level of blood oxygen measurement is still difficult.
In contrast, the transmissive finger-clip oximeters have a large number of FDA-approved and NMPA-approved, and the accuracy is generally able to reach ±2% or less. This is because these finger-clip oximeters tend to completely wrap around the test site to avoid interference from other external factors, such as light, wearing looseness, and skin thickness. These certified oximeters can be used in hospitals. In contrast, other OTC oximeters, especially smart wearable devices, are still mainly used in general health and exercise scenarios, and are not suitable for patient use, which is why such devices all state in the product interface that their oximetry data is not intended for diagnostic or medical use.
Introduction of blood oxygen monitoring
The blood oxygen monitoring function on smartwatches is mainly used to determine whether the human body is healthy or not by monitoring human arterial blood oxygen saturation. Blood oxygen saturation is the percentage of hemoglobin content in the blood that is bound to oxygen, i.e. the concentration of blood oxygen in the blood. Oxygen saturation is an important measure of human health.
The role of the oxygen monitoring function
When engaging in outdoor sports such as mountaineering
The higher the altitude, the thinner the air, and the lower the blood oxygen saturation level of the human body. When engaging in outdoor activities at high altitude, monitoring blood oxygen saturation can be used to assess your physical condition in real time, so that you can adjust the intensity of your exercise.
When drinking alcohol
The human body needs three units of oxygen to completely break down one unit of alcohol. Therefore, lack of oxygen is one of the most important signs of intoxication. But people who have been drinking heavily for a long time have a hard time noticing when they are slightly drunk because of their body's tolerance. Such people need to pay more attention to monitoring changes in blood oxygen while drinking.
High-intensity mental labor
The brain's oxygen consumption accounts for 20 percent of the total body's oxygen intake, and the brain's oxygen consumption rises with high-intensity mental labor. People who study or work long hours every day need to monitor their oxygen saturation levels.
Introduction of blood oxygen
Blood oxygen refers to the oxygen in the blood, and the normal oxygen content of the human body is about 90%. The higher the oxygen level in the blood, the better the person's metabolism. Of course, high blood oxygen content is not a good phenomenon, the body's blood oxygen is a certain degree of saturation, too low will cause the body to supply insufficient oxygen, too high will lead to the body of cellular aging. It is generally believed that the blood oxygen saturation should be no less than 94% normal, below 94% for insufficient oxygen supply.