BACKGROUND AND OBJECTIVE In preterm infants receiving supplemental oxygen, routine manual control (RMC) of the fraction of inspired oxygen (FiO2) is often difficult and time consuming. The investigators developed a system for closed-loop automatic control (SPOC) of the FiO2. The objective of this study is to test a revised, new algorithm with 3 adaptions against the former old algorithm and against RMC. The 3 adaptions are:~Faster re-adjustment to baseline-FiO2 (baseline FiO2: mean FiO2 during the previous 5min)~Delayed reduction of FiO2 below baseline FiO2~Maximum FiO2 adjustable by user~The first primary hypothesis is, that the application of SPOCnew in addition to RMC results in more time within arterial oxygen saturation (SpO2) target range compared to RMC only. The a-priori subordinate hypothesis is, that the revised algorithm is more effective as the old algorithm to maintain the SpO2 in the target range.~The second primary hypothesis is, that the shortening of averaging time used for the SpO2 Signal from 8 seconds to 2 seconds results in more time within SpO2 target range for both, SPOCnew and SPOCold.~Further hypotheses for exploratory testing are, that the SPOC new algorithm will achieve a lower proportion of time with SpO2 above and below the target range, hyper- and hypoxia and an improved stability of cerebral oxygenation (measured as rcStO2 and rcFtO2E determined by Near-infrared spectroscopy) compared with SPOCold and RMC. Reduction of staff workload (estimated by number of manual adjustments per hour) by SPOC. Validation of a clinical scoring tool to monitor severity of apnea of prematurity.~STUDY DESIGN The Study is designed as a single-center, randomized controlled, cross-over clinical trial in preterm infants receiving mechanical ventilation or nasal continuous positive airway pressure or non-invasive ventilation and supplemental oxygen (FiO2 above 0.21). Within a 30-hour period the investigators will compare 6 hours of RMC with 12-hour periods of RMC supported by SPOCnew algorithm or SPOCold algorithm, respectively. During intervals with SPOC control the SpO2 Signal averaging time will be 2 second or 8seconds , respectively, for 6 hours each.
Single-center, randomised controlled, cross-over clinical trial in preterm infants born at gestational age below 34+1/7 weeks receiving supplemental oxygen and respiratory support (continous positive airway pressure (CPAP) or non-invasive ventilation (NIV) or invasive ventilation (IV)). Routine manual control (RMC) of the fraction of inspired oxygen (FiO2) will be tested against RMC supported by automatic control (SPOC) with old-algorithm and RMC supported by CLAC with new-algorithm.~The first primary hypothesis is, that the use of the new algorithm results in more time within arterial oxygen saturation (SpO2) target range compared to RMC only. The a-priori subordinate hypothesis is, that the new algorithm results in more time within SpO2 target range compared to SPOCold.~The second primary hypothesis is, that the use of 2 seconds averaging time of the SpO2 Signal results in more time within arterial oxygen saturation (SpO2) target range compared to the use of 8 seconds averaging interval of the SpO2 signal.