S100B protein and near infrared spectroscopy in preterm and term newborns.

Cerebral monitoring constitutes an emerging issue in perinatal medicine. Near Infrared Spectroscopy (NIRS) monitors brain oxygenation status in sick infants although data in healthy infants are lacking. The present study investigates whether NIRS parameters change according to gestational age and correlate with S100B protein. We recruited 64 healthy newborns (weeks' gestation: 30-42 wks) in which we performed in the first 6-hours after birth routine clinical, radiological and laboratory variables, cerebral oxygen saturation (rSO2), fractional cerebral tissue oxygen extraction (FTOE) values and S100B urine assessment. rSO2 and FTOE correlated (R=-0.73; R=0.51; P less than 0.01, for both) with gestational age. Highest rSO2 and the lowest FTOE peaks (P less than 0.001) were found at 30-33 wks. From 34 wks onwards, rSO2 progressively decreased and FTOE increased reaching their lower dip/peak (P less than 0.001) at 38-39 weeks. A significant correlation between S100B and NIRS parameters (rSO2: r=0.77; FTOE: r=-0.69; P less than 0.01) has been found. The present study shows that NIRS parameters and S100B protein correlation may be of help in brain function monitoring.