With the social and economic development, people's living standards are improving day by day, and the attention to their own health status is also increasing, in addition to the new crown epidemic that has had a profound impact on the world in the past two years, the monitoring needs for common chronic diseases and human sub-health conditions have also made people pursue more simple and close monitoring equipment.
At present, the most commonly used and effective way is still to go to hospitals and other health institutions for regular physical examinations, but the aging of the population, uneven medical resources and other factors are promoting the transformation of traditional medical methods, mobility and portability have become the key factors in the development of the medical electronics industry, the original can only be used in the hospital fixed equipment, functions, will gradually be more miniaturized, low-cost way to achieve.
In recent years, smart wearable devices such as smart watches and bracelets are becoming the best carriers for health monitoring functions, so that the characteristics of carrying and directly touching the human body meet the key needs of such devices, and with the continuous development of mobile communications, big data, artificial intelligence and other technologies.
So, how do smart wearable devices monitor health? Can it achieve perfect health management functions? To clarify these two problems, we need to introduce the PPG and ECG that have become the mainstream functions of smart watches and bracelets.
The full name of PPG is photoplethysmography. In principle, it emits a beam of light of a certain wavelength (generally green light) to the skin, and then receives it by the photoelectric receiver by projection or reflection, and processes and displays the periodic light intensity changes detected during this process due to blood circulation, resulting in pulse data.
PPG can also be used to measure blood oxygen values, the principle is that the oxygen content of different blood reflectivity is different, the same can be detected by the photoelectric receiver its change, and then through the algorithm to process and estimate, to obtain blood oxygen values.
It is easy to find that the data used in the PPG principle comes entirely from the light signal transmitted or reflected by the human body, and thus can be deduced from the pulse, blood oxygen, and even blood pressure. Its advantages are obvious, that is, it does not require any invasive or sampling detection methods, that is, as a watch does not need to prick you with a needle, it is very suitable for daily wear; The disadvantages are also obvious: the value is estimated by the algorithm and is susceptible to environmental interference, such as the wearer's own movement, body surface sweat and other factors that affect photoelectric detection.
Let's talk about ECG, which is commonly used in the medical field, as a relatively professional health monitoring method, mainly appears in some high-end smart watches. The principle lies in the collection of bioelectric signals, and the potential difference and changes in different parts of the human body can be restored to a variety of values, including heart rate, after being processed by algorithms (yes, or algorithm estimation).
In hospitals, electrocardiograms generally place multiple patch electrodes in the chest and abdomen, etc., in order to read the strongest signal possible far enough from the heart, but the watch is only a device fixed on the wrist, how to achieve this condition? The mainstream solution is to make the non-wearable hand touch the crown of the watch when measuring, that is, to measure the potential difference from the worn wrist to the tip of the non-wearing fingertip.
The measurement method of ecg principle on smart wearable devices is more accurate than PPG, but the coverage is relatively small, and the electrocardiogram itself can reflect a considerable amount of human health data, but the current application on smart watches obviously cannot reach the sensitivity and processing power of hospital professional equipment. Therefore, ECG is more accurate and can only refer to the heart rate, how each smart wearable brand to integrate the value of PPG and ECG to obtain a health management plan, depends on their respective algorithm level.
In the final analysis, smart wearable devices can not break through the physical limitations of size, in the health monitoring function must rely on algorithm supplements, in our health management status is also based on real-time monitoring and early warning, more prominent all-weather and portability rather than professionalism.
However, we have recently seen in some new products that such smart wearable devices are helping consumers "make decisions", such as the product itself is defined as a "wrist ECG blood pressure recorder" rather than a "smart watch" of a brand WATCH D, this product can be equipped with high-performance PPG, ECG and blood pressure measurement special airbag data, heart health, vascular health, sleep breathing, body temperature and other research, and through the sports health APP and third-party platform to provide 7* 24-hour consultation and other health consultation services.
This shows that smart wearable devices are developing from simple portable monitoring devices to actively influencing our lives, which is an inevitable trend from an intelligent point of view, and it is also beneficial to users as a whole, but the development of portable monitoring technology and algorithms still needs our continuous attention. Under the premise that there are still many interfering factors and the monitoring results cannot guarantee that everything is foolproof, is it too early to give the "decision-making power" of health management to smart wearable devices?