The development of low-cost systems for measuring medical parameters is currently an important issue since this type of system ensures that any sector of the population can access these technologies. Likewise, pandemic situations, such as the one experienced some months ago due to SARS-CoV-2, require the rapid availability of diagnostic devices. One of the devices, which has turned out to be the most relevant in the early detection of respiratory problems, is the finger pulse oximeter. However, the default information that these devices offer is limited. This paper presents the process carried out to analyze the data measured by a commercial pulse oximeter and takes advantage of them to extract relevant information about the vital parameters of the patient that is being monitored, such as peripheral oxygen saturation (SpO₂), pulse rate (bpm) (PR), respiratory rate (RR/min), perfusion index (%) (Pi), plethysmography wave, plethysmographic variation index (%) (PVi), the shape of the dicrotic fissure, and the area under the curve. To do this, the Bluetooth frames generated by the device are analyzed through reverse engineering and processed to obtain the aforementioned parameters. Finally, an application for Android devices is developed in order to facilitate the collection and reading of the parameters. The system is tested with different patients whose results are validated by a physician.

中文翻译：

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低成本脉搏血氧仪的开发，用于获取医学科学参数以监测远程患者

开发用于测量医疗参数的低成本系统目前是一个重要问题，因为这种类型的系统可确保人口中的任何部分都可以使用这些技术。同样，大流行情况，例如几个月前由于 SARS-CoV-2 而经历的情况，需要快速提供诊断设备。手指脉搏血氧仪是一种被证明与早期发现呼吸问题最相关的设备。但是，这些设备提供的默认信息是有限的。本文介绍了分析商用脉搏血氧仪测量数据的过程，并利用它们提取有关被监测患者生命参数的相关信息，例如外周血氧饱和度 (SpO ₂)、脉率 (bpm) (PR)、呼吸频率 (RR/min)、灌注指数 (%) (Pi)、体积描记波、体积描记变化指数 (%) (PVi)、重肌裂的形状和曲线下的面积。为此，通过逆向工程分析设备生成的蓝牙帧并进行处理以获得上述参数。最后，为了方便参数的收集和读取，开发了一个Android设备的应用程序。该系统使用不同的患者进行测试，其结果由医生验证。