Administration of 100% Oxygen during Deferred Cord Clamping Does Not Cause Systemic Hyperoxia in Infants Born Extremely Preterm.

Abstract

To evaluate cerebral oxygenation and hemodynamic changes in infants born extremely preterm receiving 100% oxygen compared with 30% during deferred cord clamping (DCC). Infants born at 22^0/7 to 28^6/7 weeks received DCC for 90 seconds in conjunction with 30% (LO group) or 100% (HI group) oxygen. After cord clamping, infants were resuscitated per current guidelines (30% oxygen and titration based on peripheral atrial oxygen saturation, SpO₂). Heart rate, mean airway pressure (MAP), SpO₂ and inspired fraction of oxygen (FiO₂) were collected for 10 minutes. Blood pressure and cerebral tissue oxygenation were collected for 24 hours. Longitudinal models were used to compare effects of high vs low oxygen. Seventy-four infants had detailed monitoring at birth (72 infants had 24-hour cerebral monitoring). There was no difference between groups across the first 10 minutes in MAP, FiO₂, blood pressure, heart rate, or cerebral tissue oxygenation. Infants in the LO group had lower SpO₂ at 4, 5, and 6 minutes (P < .05). Cord arterial PO2 (PaO₂) was similar in both groups. The duration of hyperoxemia (SpO₂ >95th percentile on Dawson curves, HI 156 ± 145 vs LO 103 ± 122 seconds, P = .18) or hypoxemia (<25^th percentile, HI: 127 ± 89 vs LO: 121 ± 79 seconds, P = .89) were similar between the groups. Providing high oxygen during DCC transiently improves SpO₂ without causing hyperoxia or changes in MAP or FiO₂. A large, randomized controlled trial is needed to determine if 100% oxygen during DCC improves survival and reduces longer-term morbidities in infants born extremely preterm.