O3285: Trends in Outborn Periviable Infants Transported to a Single Center

Background: The survival of periviable infants born < 25+6 weeks gestation has significantly improved over the past 50 years. Historically infants born at 22-23 weeks gestation were considered nonviable and were not offered active resuscitation, however, recently there have been centers reporting >50% survival for infants born at 22-23 weeks gestation. Our institution has shifted our practice to offer more active resuscitation to 22-week infants. We hypothesize that as we expand our resuscitation practices to inborn patients, that we have also seen an increase in the number of requests to transport periviable infants from level I and II nurseries to our level IV NICU.

Methods: This is a retrospective review of periviable infants born between 22+0 to 25+6 weeks gestational age infants born at the Monroe Carrell Jr Children’s Hospital at Vanderbilt (MCJCHV) and those transported in the first 24-hours of life to MCJCHV by our Neonatal Transport Team from 2015-2022. There were 291 inborn infants and 76 outborn infants who met criteria. Trends over time were compared using the Mann-Kendall trend test.

Results: Of the 291 inborn infants, there was a significant increase in the number of 22-week infants over time (p 0.025). The number of 23, 24, and 25-week infants remained stable with p values of 0.530, 0.308, and 0.167 respectively. Among the outborn patients, there was a significant increase in both 23-week (p 0.026, Figure 1) and 24-week (p 0.015, Figure 2) infants transported to our facility, while no difference was noted in the 22-week (p 1.00) and 25-week (0.667) population.

Conclusion: We have seen a significant increase in periviable infants transferred to our NICU over time. Before 2019 we performed approximately 6 transports/year of infants born < 25+6 weeks gestation; since 2019 we have been performing up to 17 periviable transports/year. While our single center numbers are small, we demonstrate an important trend in periviable practices in our community. There are a number of potential reasons for this trend. One consideration is decreased number of maternal transports, potentially due to decreased EMS availability in recent years. However, we saw no change in the number of infants transported at 25 weeks which could indicate the same access to maternal transport in the community. We therefore hypothesize that as experienced NICUs continue to offer and improve resuscitation techniques and the standard of care shifts toward resuscitating infants as young as 22 weeks, that we are seeing a change in community practice toward this new norm as well. This emphasizes the importance of developing protocols for the resuscitation and transport of periviable infants to improve outcomes as outborn premature infants are at higher risk for complications of prematurity including death, sepsis, chronic lung disease, and intraventricular hemorrhage.