University Of Bath Engineer Shares DIY Instructions For 3D Printed Blood Oxygen Sensor

University of Bath engineer shares DIY instructions for 3D printed blood oxygen sensor

Engineers at the University of Bath have shared the design of a low-cost 3D-printed blood oxygen sensor to help monitor COVID-19 symptoms.

Anyone with a 3D printer and basic electronics can build this "open oximeter" sensor designed by a team of engineers and scientists. For less than £10, it can accurately monitor a person's blood oxygen levels. Decreased blood oxygen level is the main symptom of new coronary pneumonia. Based on the existing blood oxygen sensor, the oximeter measures the reflection of light of different wavelengths by clipping on the fingernail, so as to track the heart rate and blood oxygen saturation of the measurer.

The design, which includes sensors, readout electronics and software, has been published in the Open Hardware Journal. Design files have been shared on GitLab. It was created in response to the first wave of the Covid-19 pandemic in 2020, during which time staff at the University of Bath's School of Engineering and Design produced over 200,000 PPE for local healthcare workers, while local companies produced another 200,000 of its designs. Various PPEs.

"This project was initiated in response to a potential shortage of pulse oximeters because of the large number of patients requiring oxygen saturation measurements," said Dr Pejman Lavaney, senior lecturer in mechanical engineering.

Professor Peter Wilson, from Bath's Department of Electrical and Electronic Engineering, added: "During the Covid-19 pandemic, monitoring blood oxygen saturation has become a critical part of patient care, especially early warning of serious illness. Hence the need for pulse oximeters worldwide. The demand is increasing and the demand is huge. We hope that by sharing this open source design, medical device providers will be able to quickly produce more oximetry instruments at a reasonable cost."

The NHS recently issued guidelines for monitoring blood oxygen saturation levels in patients with Covid-19 using a pulse oximeter at home. Scientists are trying to understand why the oxygen levels in the blood of Covid-19 patients suddenly drop without them noticing. They call this phenomenon "silent hypoxia."

Plans to Improve Calibration and Eliminate Racial Bias

The team is currently working with the University of Cambridge to develop low-cost "phantoms" (artificial fingers) that can be used to calibrate and validate oximeters. These will also help address racial bias in oximeters, which are more accurate for people with lighter skin.

Lecturer Dr Ben Metcalfe added: "Accurate measurement is a top priority for oximeters. A recent study published in the New England Journal of Medicine's Improving Calibration and Eliminating Racial Bias program clearly shows that race Bias exists in current oximetry instruments. It is concerning that patients who are identified as black have higher blood oxygen saturation than they actually are. It is well known that the calibration of pulse oximeters (especially seen in many Covid-19 patients) low oxygen saturation levels) are technically challenging. By creating 3D printed materials with known optical properties, we can develop phantoms that can be calibrated at these lower oxygen levels."