Automation control algorithms in gas mixture for preterm infant oxygen therapy

Abstract

Pre-term infants often suffered from immature lung development, which caused oxygen saturation (SpO2) to be fewer than 90% (98-100% for normal infants). Oxygen therapy was an essential treatment - supply right proportional air-oxygen gas content called a fractional of inspired oxygen (FiO2) via nasal cannula - to control SpO2 in a range of 90-95% and to maintain life. Registered nurses (RN) were routinely responsible for adjusting FiO2 between 21-100% according to a current SpO2 and a doctor's order. The objective was to supply FiO2 as low as possible while maintaining SpO2 in a suitable range. However, manual adjustments were not in real time (normal every 20-30 minutes) which could introduce risk of either oxygen toxicity from too high SpO2 or hypoxia from too low SpO2. This research was to develop an automatically control of FiO2 according to an order SpO2 by medical doctors. The result of this research could reduce risk of blindness from oxygen toxicity as well as mortality from hypoxia in pre-term infants. The system also allowed medical doctors to use recorded data for future care plan in oxygen therapy. This research introduced two different algorithms for such purposes and described a design of such system.