Oxygen at birth and prolonged cerebral vasoconstriction in preterm infants.

To determine if the use of oxygen in the delivery room influences subsequent global cerebral blood flow (CBF), 70 infants of gestational age of less than 33 completed weeks were randomly assigned to receive room air (group I) or 80% oxygen (group II) during the initial stabilisation at birth. In group I supplemental oxygen was administered on clinical indications, when required. After being admitted to the neonatal intensive care unit all infants were treated according to our normal practice. At a postnatal age of 2 hours CBF was measured by xenon clearance. Seventy four per cent of the infants in group I were successfully stabilised without the need for supplemental oxygen. CBF was significantly higher in group I than in group II (CBF median (interquartile range): 15.9 (13.6-21.9) v 12.2 (10.7-13.8) ml/100 g/minute). Differences in oxygen exposure seemed to be the only explanation for the differences in CBF. No differences in short term outcome were found between the groups.