466 - Comparison of Clinical Variables in Extremely Preterm Infants Enrolled versus Not Enrolled in the VentFirst RCT of Assisted Ventilation Prior to Cord Clamping

Publication Number: 1448.466

Karen Fairchild, University of Virginia School of Medicine, Charlottesville, VA, United States; Jennifer L. Fang, Mayo Clinic Children's Center, Rochester, MN, United States; Justin Josephsen, Saint Louis University School of Medicine, Saint Louis, MO, United States

Background: In the VentFirst RCT of infants < 29 weeks gestation, antenatal informed consent was required. Consented mothers were randomized prior to delivery to their infant receiving assisted ventilation prior to cord clamping at 120 seconds (intervention) or up to 60 seconds of delayed cord clamping followed by assisted ventilation (control). Given the time required for consent, randomization and equipment set-up, VentFirst-enrolled infants were likely to have a less emergent delivery. We hypothesized that infants enrolled in VentFirst would have different clinical characteristics and outcomes compared to non-enrolled < 29 week gestation inborn infants.

Objective: Compare clinical characteristics and outcomes of infants enrolled versus not enrolled in VentFirst.

Design/Methods: In this observational study, we identified infants born at 23 0/7 to 28 6/7 weeks gestation at two VentFirst sites during the years of the VentFirst trial (2016-2022). Data were extracted from the VentFirst database for enrolled (VF) infants and from electronic health records for non-enrolled (NE) infants. For the combined site cohorts, VF and NE infant data were compared using Mann-Whitney U tests for continuous variables and Fisher's exact tests for categorical variables.

Results: Data were analyzed for 150 VF and 321 NE infants. Gestational age, birthweight, NICU admission temperature, and incidence of any grade IVH were similar for the two groups (Table 1). Cord clamping time was significantly longer for VF versus NE infants (median [IQR] 60 [26, 106] vs. 10 [10, 60] seconds, p< 0.001). Cord milking was performed in no VF infants (per study protocol) versus 14% of NE infants (p < 0.001). Severe IVH occurred significantly less frequently in VF compared to NE infants (6.7% vs. 13.5%, p=0.037).

Conclusion(s): In this ongoing observational study, data from two sites show that infants enrolled in the VentFirst RCT were significantly less likely to have severe IVH compared to < 29 week gestation non-enrolled infants. Comparison of VF and NE data from other VentFirst sites will be complete in early 2026. Consideration should be given to alternatives to traditional informed consent in resuscitation research in order to improve the generalizability of study findings.

Table 1
Two-site comparison of infants enrolled in the VentFirst RCT versus <29 week GA inborn infants not enrolled