Enhanced Pulse Oximetry Systems: Design, Signal Processing, and Clinical Validation

Ahmed Thamer Saud Faisal; Anas Ahmed Noaman  Turki; Ayham Mahmoud Taha  Hussein; Mohammed Hussein Ahmed  Jaaid

doi:10.51699/cajmns.v7i1.3028

Ahmed Thamer Saud Faisal Al-Farahidi University, Medical Technical College, Medical Devices Technologies Engineering, Iraq
Anas Ahmed Noaman Turki Al-Farahidi University, Medical Technical College, Medical Devices Technologies Engineering, Iraq
Ayham Mahmoud Taha Hussein Al-Farahidi University, Medical Technical College, Medical Devices Technologies Engineering, Iraq
Mohammed Hussein Ahmed Jaaid Al-Isra University, Medical Technical College, Medical Devices Technologies Engineering, Iraq

DOI: https://doi.org/10.51699/cajmns.v7i1.3028

Keywords: Pulse Oximetry, Photoplethysmography, SpO₂ Measurement, Medical Device Design

Abstract

This in-depth study delves into the basics, hardware design, and clinical trials of contemporary pulse oximetry technology. By thoroughly analyzing photoplethysmographic signal processing, we designed and evaluated a transmission-mode pulse oximeter that used dual-wavelength optical sensing at 660 nm (red) and 940 nm (infrared).The research goes beyond accuracy issues raised by the FDA due to changes in skin pigmentation and focuses primarily on removing bias in populations with melanin-rich skin. Our prototype features a top-notch analog front-end (AFE4403) combined with adaptive filtering algorithms and hence, it achieves an accuracy root mean square (ARMS) of 1.8% in the 70-100% SpO₂ range. The clinical validation included 150 subjects who were categorized according to the Fitzpatrick skin type's I-VI. It was found that the device performance for the darkly pigmented population was significantly better than that of the baseline instruments (bias changed from +3.2% to +0.8%).The apparatus reveals a reaction time of fewer than 5 seconds, a noise from motion removal capability of over 90% and an energy consumption of 45 mW, thus, it can be used in both clinical and home monitoring settings. Such results constitute a significant step towards the elimination of racial and ethnic disparities in the performance of medical devices while at the same time, fulfilling the diagnostic accuracy requirements for critical care decision-making.

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