Increasing Visibility of Oxygen Concentrator Performance Using an Embedded Purity Display

Abstract

Oxygen concentrators have and will continue to play an essential role in healthcare delivery in low- and middle-income countries (LMICs). Performance degrades over time resulting in reduced oxygen concentration, which has less therapeutic benefit for the patient. The World Health Organization recommends oxygen concentration of at least 82% for patient care. Oxygen concentrator manufacturers implement visible and audible alarms to indicate low oxygen concentration. However, the alarm thresholds vary widely, from 65% to 85%, and there is no consistency in the implementation of alarms across manufacturers. We propose the addition of a display that shows the actual oxygen concentration being generated. We believe this will allow clinicians, who are the primary users of oxygen concentrators in LMICs settings, to make more informed decisions. We tapped into the serial data communication for the diagnostic port of a DeVilbiss oxygen concentrator to intercept oxygen concentration levels, and displayed them on a clearly visible two-digit display. We developed a working oxygen concentration display, which we embedded into the front panel of a DeVilbiss oxygen concentrator. Serial data was decoded and formatted for display purposes using a microcontroller. The display digits were green and measured 0.8 inches (21 mm) in height. The display blinks once per second when oxygen concentration drops below 82%, making it more noticeable than the small, continuously lit visible indicators used by most manufacturers. The entire electronics cost less than USD 10, using parts we had available in-house. Our proof of concept allowed us to demonstrate the feasibility of the idea and think through the challenges and potential costs associated with this intervention. We recommend formal usability testing in the hope that it will reduce uncertainty around the potential risks and benefits of giving clinicians access to the actual concentration of oxygen being generated.