Respiratory support prior to cord clamping in very preterm infants: a narrative review with pooled results from recent studies.

Background: Whether very preterm infants benefit from provision of respiratory support prior to cord clamping has been an important knowledge gap. Four randomised controlled trials have recently been published on this topic and have provided new insights. These 4 studies and 2 previous ones included preterm infants less than 32 weeks gestational age receiving deferred cord clamping (DCC). The intervention consisted of providing respiratory support in the form of Continuous Positive Airways Pressure (CPAP) or positive pressure ventilation via T piece. The intervention group had cord clamping performed when pre-set stability criteria were met in one study or after an elapsed time of up to 120s was achieved in the other 5 studies (50 to 120s range). The control group had time-based cord clamping after 30 to 60 s without respiratory support (5 studies) or cord milking (1 study).

Summary: Outcome measures based on important neonatal outcomes such as death, severe intraventricular haemorrhage (sIVH) and bronchopulmonary dysplasia (BPD) were reported as were other outcomes such as admission temperature and transfusions. Overall outcomes (death, sIVH and BPD) were similar in intervention and control groups in these studies with moderate certainty of evidence to conclude there was no benefit for these outcomes. Maintaining normothermia was difficult and the mean difference in admission temperature was significantly lower in the intervention group, although hypothermia was generally mild.

Key Message: Overall, the provision of respiratory support during DCC did not improve important neonatal outcomes (moderate certainty of evidence). Although we do not currently recommend the procedure as routine practice, we acknowledge there is room for further studies.