Reference Ranges for Regional Cerebral Oxygen Saturation with Masimo O3 after Birth and Differences with Other Devices

Abstract

- Objective: Cerebral oximetry using near-infrared spectroscopy (NIRS) is a non invasive optical technology widely used in neonatology. Aim of the present studio was to define reference ranges for cerebral tissue oxygen saturation (crSO2) with a new 4 wavelength NIRS device, Masimo O3® oxymeter, during inmediate transition after birth and compare values with those obtained previously with NIRO 200NX®. -Study design: This was a prospective observational study using Masimo O3 device to measure crSO2 and regional cerebral fractional tissue oxygen extraction (cFTOE) in healthy term newborns delivered by primary cesarean section, during the 15 minutes after cord clamping. The neonates who required any medical support were excluded. The NIRS-sensor was placed in the right forehead. Peripheral oxygen saturation and heart rate were continuously measured by pulse oximetry. Previous studies which established centiles for crSO2 with NIRO 200 NX were used to compare. -Results: A total of 44 newborns were included. The median crSO2 and cFTOE (interquartile range) at 2, 5 and 7 minutes was 54% (49-54); 71% (64-86) and 79% (73-84) and 0,25 (0,18-0,33); 0,19 (0,15-0,23) and 0,16 (0,12-0,21), respectively ,with no further changes afterwards. The crSO2 measurements were significantly higher with Masimo O3 compared NIRO-200NX. -Conclusion: The present observational study presented reference ranges for crSO2 and cFTOE measured with Masimo O3 oxymeter during the inmediate neonatal transition. Values obtained with O3 were higher than those obtained with others oxymeters. For this reason, crSO2 is device-specific so it must be known reference values for each oxymeter to define therapeutic interventions based on crSO2 and asses cerebral oxygenation clinical studies.