[Association between time of birth and resuscitation outcomes in extremely preterm infants]

To study whether there are differences in the resuscitation process and early outcomes between the extremely preterm infants delivered on off-hours (6 pm to 8 am of working days, weekends, and national holidays) and those delivered on working hours.

A retrospective analysis was performed on the medical data of extremely preterm infants who were born in the Peking University Third Hospital from January 1, 2010 to December 31, 2020 and transferred to the neonatal intensive care unit (NICU). According to the time of birth, they were divided into two groups:working hours (n=77) and off-hours (n=98). The resuscitation process and early outcomes were compared between the two groups.

Compared with the working hours group, the off-hours group had a significantly lower proportion of infants with the use of full-dose dexamethasone before delivery (P < 0.05) and a significantly higher proportion of infants with a 1-minute Apgar score of < 7, positive pressure ventilation, or tracheal intubation (P < 0.05). The incidence rates of neonatal respiratory distress syndrome and intrauterine pneumonia in the off-hours group were significantly higher than those in the working hours group (P < 0.05).

Extremely preterm infants delivered on off-hours tend to have a low Apgar score at 1 minute after birth, with a higher proportion of infants requiring positive pressure ventilation or tracheal intubation during resuscitation than those delivered on working hours, and they tend to develop neonatal respiratory distress syndrome and intrauterine pneumonia. This suggests that it is important to make adequate preparations in terms of personnel and supplies for resuscitation of extremely preterm infants after birth and that NICUs should develop a detailed management plan for extremely preterm infants at each period of time before, during, and after birth.