Growth restriction and gender influence cerebral oxygenation in preterm neonates

Objective To investigate the effect of fetal growth restriction and gender on cerebral oxygenation in preterm neonates during the first 3 days of life. Design Case-control study. Setting Neonatal Intensive Care Unit of the Wilhelmina Children's Hospital, The Netherlands. Patients 68 (41 males) small for gestational age (SGA) (birth weight <10th percentile) and 136 (82 males) appropriate for gestational age (AGA) (birth weight 20th-80th percentile) neonates, matched for gender, gestational age, ventilatory and blood pressure support. Methods Regional cerebral oxygen saturation (rScO2) and cerebral fractional tissue oxygen extraction (cFTOE) as measured by near-infrared spectroscopy throughout the first 72 h of life were compared between SGA and AGA neonates. The effect of gender was also explored within these comparisons. Results SGA neonates demonstrated higher rScO(2) (71% SEM 0.2 vs 68% SEM 0.2) and lower cFTOE (0.25 SEM 0.002 vs 0.29 SEM 0.002) than AGA neonates. There was an independent effect of gender on rScO(2) and cFTOE, resulting in the finding that SGA males displayed highest rScO(2) and lowest cFTOE (73% SEM 0.3 respectively 0.24 SEM 0.003). AGA males and SGA females showed comparable rScO(2) (69% SEM 0.2 vs 69% SEM 0.4) and cFTOE (0.28 SEM 0.002 vs 0.28 SEM 0.004). AGA females showed lowest rScO(2) and highest cFTOE (66% SEM 0.2 respectively 0.30 SEM 0.002). Conclusions Growth restriction and gender influence cerebral oxygenation and oxygen extraction in preterm neonates throughout the first 3 days of life.