Purpose: The physiologic transition from a fetus to a neonate is composed of a series of complex processes that include changes in cerebral tissue oxygenation saturation (cSO₂). Monitoring this process is of great importance. This study aimed to define the cSO₂ reference interval in neonates without medical support, extending the measurements until 1 hour after birth, and to determine the incidence of abnormally low or high regional cerebral oxygenation during the neonatal transition.
Patients and Methods: A total of 418 neonates delivered by cesarean section were enrolled. Near-infrared spectroscopy was used to monitor cerebral oxygenation.
Results: We found that cSO₂ of the non-oxygen-inhaled intrathecal anesthesia in neonates without medical support increased from about 49.0% in the second minute. Most of them reached cSO₂ relative stabilization at 55.7– 81.0% between 7 and 8 minutes after birth. One hour after birth, newborn cSO₂ was maintained at 78.0– 87.0%. The low cSO₂ rate among babies born under intrathecal anesthesia with and without maternal oxygen inhalation during cesarean sections was approximately 4.5% and 9.0%, respectively.
Conclusion: We reported the trend in cSO₂ from 2 minutes after birth to 1 hour in the neonatal nursing room and determined the incidence of abnormal regional cSO₂ during this neonatal transition period. Anesthesiologists should pay special attention to the risk of cSO₂ abnormalities in newborns when managing pregnant women with comorbidities.
Keywords: cerebral oxygenation saturation, transitional period after birth, cesarean section, anesthetic monitoring