Cerebral oxygenation during the first days of life in preterm and term neonates: differences between different brain regions.

Near-infrared spectroscopy is a noninvasive method for monitoring brain oxygenation. The aim of the study was to investigate differences between cerebral oxygenation in different brain regions in newborns. In a prospective study, we monitored simultaneously left and right frontoparietal and temporo-occipital regional cerebral oxygen saturation (rScO2) and cerebral fractional tissue extraction (cFTOE: (arterial oxygen saturation (SaO2) - rScO2)/SaO2) using near-infrared spectroscopy. A 2-h measurement was performed on d 1, 3, and 7. We included 10 very preterm (GA <32 wk), 10 preterm (GA: 32-37 wk), and 10 term (GA ≥37 wk) neonates. Limits of agreement for difference of the measurements between different places were determined using the Bland-Altman method. In all subgroups, the rScO2 and cFTOE values at different regions were not different. Limits of agreement were between ±14 and ±18% for all subgroups. Left-to-right differences were small between different postnatal and GAs. A decrease and increase over time for rScO2 and cFTOE values was detected for all four brain regions, most pronounced for infants with GA <32 wk. Cerebral oxygenation in stable preterm and term neonates seems not to differ between different regions of the brain during the early neonatal period. However, variability of individual measurements was quite high as indicated by large limits of agreement.