Clinical use of cerebral oximetry in extremely preterm infants is feasible

INTRODUCTION: The research programme Safeguarding the Brains of our smallest Children (SafeBoosC) aims to test the benefits and harms of cerebral near-infrared spectroscopy (NIRS) oximetry in infants born before 28 weeks of gestation. In a phase II trial, infants will be randomised to visible cerebral NIRS oximetry with pre-specified treatment guidelines compared to standard care with blinded NIRS-monitoring. The primary outcome is duration multiplied with the extent outside the normal range of regional tissue oxygen saturation of haemoglobin (rStO(2)) of 55 to 85% in percentage hours (burden). This study was a pilot of the Visible Oximetry Group. MATERIAL AND METHODS: This was an observational study including ten infants. RESULTS: The median gestational age was 26 weeks + three days, and the median start-up time was 133 minutes after delivery. The median recording time was 69.7 hours, mean rStO(2) was 64.2 +/- 4.5%, median burden of hyper- and hypoxia was 30.3% hours (range 2.8-112.3). Clinical staff responded to an out of range value 29 times - only once to values above 85%. In comparison, there were 83 periods of more than ten minutes with an rStO(2) below 55% and four episodes with an rStO(2) above 85%. These periods accounted for 72% of the total hypoxia burden. A total of 18 of the 29 interventions were adjustments of FiO(2) which in 13 of the 18 times resulted in an out-of-range SpO(2). Two infants suffered second-degree burns from the sensor. Five infants died. In all cases, this was unrelated to NIRS monitoring and treatment. CONCLUSION: The intervention of early cerebral NIRS monitoring proved feasible, but prolonged periods of hypoxia went untreated. Thus, a revision of the treatment guideline and an alarm system is required.