Using Pulse Oximetry Measurements for Disease Monitoring

Introduction

Inside the field of health, there are many ways to classify the different diseases suffered by humans. Chronic disease can be defined as a disease that has no cure and patients have to get different medications to alleviate it. Additionally, in most cases, patients require medical devices to follow the disease evolution. So, medical devices are essential tools or instruments for diagnosing, treating, and rehabilitating diseases. Moreover, mobile phones can be useful devices to control human activity (Lopes et al., 2011) and human body evolution (Rghioui et al., 2016). As a result, the manufacturing process, the experimentation to create useful products, and the distribution process are very rigorous. Even that, they are essential to ensure quality, accuracy in measurements, ergonomics, and compatibility with the environments in which they have to be used. In order to permit the widespread use of those devices, there is an increasing research activity amount to design and create medical devices as cheap as possible while ensuring their reliability.

On February 21, 2019, a report published by the WHO indicated that health spending had reached 10% of global gross domestic product (GDP), growing faster than the rest of the economy. This spending on health, which comes from governments, health insurance, citizens, and NGOs is remarkable according to the agency in the middle- or low-income countries where GDP grows 6% per year while in rich countries, the GDP grows by 4% (WHO, 2019). According to (WHO, 2022), most of the health expenditure goes to Primary Care. This indicates that with an improvement in this sector by investing in Research, Development, and technological innovation (R+D+i), a significant amount of money could be saved. With low-cost devices, hospitals could cover a greater number of patients without collapsing the health system since the low price of those devices permits the acquisition of more units to assist more patients and users.

Considering the reports provided by the WHO, mainly five diseases have been considered as chronic diseases. These are diabetes, cardiovascular diseases, cancer, chronic respiratory diseases, and mental disorders. People with lung conditions, such as asthma, allergies, chronic obstructive pulmonary disease (COPD) which can generate chronic inflammatory lung diseases that obstruct the lungs, or people who smoke that can suffer pneumonia, lung cancer, or other conditions can benefit from continuous monitoring of their vital signs. Older and elderly people can also suffer diseases that sometimes need to be monitored. The great importance of this type of disease leads the WHO/Europe to address risk factors and develop tools and public health guidance to help countries with less access to health (WHO, 2021). One of the main problems that this type of disease presents is that the patient is forced to go constantly to hospital consultations for both treatment and monitoring of the condition. This fact is translated into a personal and economic expense both for the patient and for the health system. In addition, a slowdown in the attention to consultations can create the worsening of pathologies that will inevitably worsen the well-being of people and, even the death of that patient (El-Rashidy et al., 2021).

On the other hand, it is worth highlighting that situation such as the one that lived due to the pandemic that began at the end of 2019, generated by the SARS‐CoV‐2 coronavirus (COVID19), are unexpected and undesirable situations out of control for most of the countries (at least in the first months). COVID-19 generated in patients a respiratory disease caused that affected the lungs (Malik et al., 2020). In the most severe cases, COVID-19 produces severe episodes of pneumonia. In extreme cases, there are cases of chronic coronavirus where many characteristic symptoms of that disease remain in the patient for a long time, even several months after the initial infection (Baig, 2020). One of the most mysterious clinical cases, of COVID-19-based diseases, was silent hypoxemia whose patients suffered a low level of oxygen in the blood and a clear respiratory difficulty. This affection could be easily detected by a simple pulse oximeter.