Hylke Salverda

54 Chapter 3 Although several devices offering AOC are now commercially available and used in Neonatal Intensive Care Units (NICUs), comparisons between them are lacking. The NICU of the Leiden University Medical Center (LUMC) implemented AOC with the CLiO2 algorithm (Vyaire, Yorba Linda, California, USA) with the AVEA ventilator as routine care in August 2015. We recently replaced the AVEA ventilators with SLE6000 ventilators (SLE Limited, South Croydon, UK), which have the VDL 1.1 algorithm for automated oxygen control embedded as the “OxyGenie” option.17, 25 This provided the unique setting where caregivers were competent to work with both ventilators, thus making feasible a safe comparison between the two oxygen controllers. Based on described differences in the function of algorithms developed for AOC it is likely that they will exhibit differences in performance.17, 25 We recently observed that CLiO2 algorithm was effective mostly in decreasing time above TR, 24 whereas the first clinical study using OxyGenie reported a decrease in both time under and above TR and a virtual elimination of longer episodes outside the TR.23 We therefore hypothesized that the OxyGenie may be more effective than CLiO2 in maintaining SpO2 within the desired TR in preterm infants receiving respiratory support. Methods Study setting We performed a randomised cross-over trial in the NICU of the LUMC, a tertiary level neonatal unit with 25 NICU beds and 850 intensive care admissions per year. The Dutch Central Committee on Research Involving Human Subjects approved the study. Written informed parental consent was acquired prior to participation of each infant in the study. Study population Preterm infants born between 24 weeks up to and including 29 weeks of gestation who were receiving invasive mechanical ventilation or non-invasive respiratory support were assessed for eligibility. Initially, infants were considered eligible if they required supplemental oxygen with an FiO2 ≥0.25 at the time of enrolment and for at least 18 hours of the preceding 24 hours, but as the study progressed an alternative FiO2 eligibility criterion was added (FiO2 coefficient of variation ≥0.1 in the preceding 24 hours) to improve recruitment rate. Infants were excluded in case of major congenital anomalies or acute instability.