Oxygen Saturation and Heart Rate Ranges in Very Preterm Infants Requiring Respiratory Support at Birth

Objective To evaluate the changes in preductal oxygen saturation (SpO(2)) and heart rate in preterm infants receiving continuous positive airway pressure (CPAP) and/or positive-pressure ventilation (PPV) at birth. Study design A prospective observational study at birth of infants aged <32 weeks separated into 2 gestational age (GA) groups: 23(0/7)-27(6/7) weeks (group 1) and 28(0/7)-31(6/7) weeks (group 2). Infants received delayed cord clamping (DCC) in accordance with institutional protocol. CPAP and/or PPV was applied at the clinical team's discretion. SpO(2) and heart rate were recorded every minute for 10 minutes. Preductal SpO(2) was targeted according to published nomograms. For heart rate, the goal was to maintain a stable heart rate >100 bpm. Results The study cohort comprised 96 group 1 infants (mean GA, 26 +/- 1 weeks; mean birth weight, 818 +/- 208 g) and 173 group 2 infants (mean GA, 30 +/- 1 weeks; mean birth weight, 1438 +/- 374 g). In general, infants requiring respiratory support reached target values for heart rate and SpO2 more slowly than the published nomograms for spontaneously breathing preterm infants without respiratory support. Infants receiving CPAP reached SpO2 and heart rate targets faster than infants receiving PPV. In group 1, but not group 2 infants, DCC resulted in higher SpO(2) and heart rate. Conclusion SpO(2) and heart rate do not quickly and reliably reach the values achieved by spontaneously breathing preterm infants not requiring respiratory support.