The feature of brain oxygenation in the sleep cycle of healthy newborn babies

Abstract

Noninvasive monitoring brain oxygenation with near-infrared spectroscopy (NIRS) is becoming a widely used in neonatology for determine the optimal target oxygen saturation during resuscitation of newborns, but its use in clinical practice for diagnostics and prognosis perinatal pathology is limited because intra and especially interpatient variability are too large for this aim. This study aimed to determine cerebral oximetry values during the sleep cycle and wakefulness in healthy full term newborns. 38 newborns (gestational age 38 weeks were included in this study (22 after normal birth I group and 16 after cesarean section). Near-infrared spectroscopy (CrSO2) from left fronto-parietal region was recorded in synchrony with polysomnography. Continuous cerebral CrSO2 were measured using near-infrared spectroscopy (Somanetic INVOS 5100C, USA). Fraction tissue oxygen extraction (FTOE) was calculated using SaO2 (pulse oximeter Radical Masimo) and CrSO2 (FTOE = (SаO2 CrSO2)/SаO2). CrSO2 and SаO2 were analyzed during 15 minutes polysomnography-defined quiet, active sleep and wakefulness (defined according to standard guidelines). The results: cerebral oxygen saturation varies with sleep-wake states: during active sleep (74,18 0,75%) was similar to the value in wakefulness (75,6 1,0%) and smaller than in quiet sleep (81,93 1,74%, р 0,001), but FTOE during active sleep was significantly higher (0,221 0,008% and 0,129 0,005%, p 0,001). There were no differences of rates between groups. The high oxygen consumption during REM sleep supports its role during postnatal brain functional development. The use of NIRS taking into account sleep structure will be new method for diagnostic and prognosis perinatal pathology CNS.