BACKGROUND: Desaturation episodes occur commonly in ventilated preterm infants. It is not clear how best to reduce the frequency and duration of desaturation. OBJECTIVE: To study the management of desaturation episodes using two bedside algorithms. METHODS: Using a randomised crossover design, over two 8-hour periods, episodes were managed with either titration of inspired oxygen (FiO(2)) alone or adjustment to ventilator pressures with smaller changes to FiO(2). Functional oxygen saturation and heart rate were downloaded from the bedside monitor. Ventilator parameters were captured simultaneously. The primary outcome was the proportion of time in the target saturation band. A cumulative measure of desaturation and oversaturation was also developed to compare groups. RESULTS: 33 studies were performed in 23 ventilated infants <32 weeks' gestation. Infants spent 51% of the time with saturations in the target band. There were more changes in ventilator pressure when the second algorithm was in use. There was no difference in the proportion of time within the saturation target, in the frequency and duration of desaturation episodes, or in the desaturation/oversaturation index between the two algorithms. CONCLUSIONS: Further study is required to determine the best way to manage desaturation in ventilated preterm infants. (c) 2008 S. Karger AG, Basel.