Oximeters and Ventilators (Seminar)

Jones Seminar on Science, Technology, and Society.
"Oximeters and Ventilators for Battling COVID-19."
Yasser Khan, Postdoctoral Scholar, Stanford University.
October 30, 2020.

Coronavirus disease 2019 (COVID-19), being a respiratory illness, has created an unprecedented need for blood-oxygen monitoring and breathing-assistance devices. Hence, oximeters and ventilators are two of the most important medical devices for battling COVID-19. In this two-part talk, I will first focus on low-cost large-area sensors for oximetry. Conventional oximeters use expensive and rigid optoelectronic components that restrict sensing locations to fingertips or earlobes. To address these limitations, we demonstrated an all-organic optoelectronic sensor for transmission- and reflection-mode oximetry. I will discuss the design, sensing methodology, and fabrication of a flexible and printed sensor array, which senses reflected light from tissue. Due to the mechanical flexibility, 2D oxygenation mapping capability, and the ability to place the sensor in diverse places, the sensor is promising for mapping oxygenation in tissues, wounds, or transplanted organs.

In the second part of the talk, I will present a low-cost (less than $200), portable (fits in an 8”x8”x4” box), non-invasive ventilator (NIV), designed to provide relief to early-stage COVID-19 patients in low-resource settings. Our design supports continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BiPAP) modes. A common concern of using CPAP or BiPAP for treating COVID-19 patients is the aerosolization of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We used a helmet-based solution that contains the spread of the virus. Our end-to-end solution is compact, low-cost (less than $400 including the helmet, viral filters, and a valve), and easy-to-use. Our NIV provides 0-20 cmH2O pressure with flow rates of 60-180 Lmin−1. Finally, I will wrap up by presenting the preliminary data of our helmet-based NIV clinical trial on COVID-19 patients.