Initial CPAP of 5 versus 8 cmH2O during delivery room stabilisation of very preterm infants: the PHILODENDROOM pilot randomised trial

Abstract The objective was to evaluate the feasibility and safety of conducting a randomised controlled trial comparing two initial continuous positive airway pressure (CPAP) levels during delivery room (DR) stabilisation of very preterm infants at risk for respiratory distress syndrome (RDS) and to explore their early physiological respiratory effects. In this pilot randomised controlled trial conducted at a tertiary neonatal intensive care unit, preterm infants born between 26 + 0 and 29 + 6 weeks’ gestation requiring respiratory support at birth were randomised to receive CPAP at either 5 cmH 2 O or 8 cmH 2 O via face mask and T-piece resuscitator during the first 15 minutes of life. The primary objective was to assess trial feasibility and safety. Pre-specified exploratory outcomes included the preductal SpO 2 /FiO 2 (S/F) ratio at 15 minutes after birth, need for positive pressure ventilation (PPV), surfactant administration, respiratory support requirements and respiratory morbidity. Fifty-six infants were enrolled and equally randomised between groups. The pre-defined sample size was achieved, protocol adherence was completed, and no participant was lost to follow-up, confirming the feasibility of trial conduct. Baseline characteristics were comparable. No significant differences were observed in pre-defined safety outcomes, including pneumothorax, pulmonary interstitial emphysema, or DR intubation. The S/F ratio at 15 min was similar between groups (271 ± 101 vs. 269 ± 111; p = 0.95). The proportion of infants requiring PPV was identical in both groups (35%). Although the overall surfactant administration rate did not differ, infants receiving 5 cmH 2 O reached surfactant treatment threshold earlier than those receiving 8 cmH 2 O (2.2 ± 1.7 vs 3.5 ± 2.1 h; p = 0.03). Trends towards shorter MV duration and lower BPD incidence were observed in the 8 cmH 2 O group, without statistical significance. Conclusion : This pilot randomised trial demonstrated that comparing two initial CPAP strategies during DR stabilisation of very preterm infants is feasible and no significant adverse events have been reported. While higher initial CPAP was associated with delayed achievement of the FiO 2 threshold for surfactant administration, exploratory physiological and clinical findings should be considered hypothesis-generating. Adequately powered multicentre trials incorporating physiological bedside assessment of lung aeration are needed to determine the optimal initial CPAP strategy during neonatal transition. What is Known: • CPAP is a cornerstone of respiratory support for very preterm infants in the DR, but the optimal initial distending pressure remains uncertain. • Higher CPAP levels may improve lung recruitment, although concerns persist regarding air leaks and potential harm. What is New: • In this pilot trial, both 5 and 8 cmH2O initial CPAP levels were feasible and safe during DR stabilisation of very preterm infants. • Higher initial CPAP was associated with delayed surfactant threshold achievement, highlighting the potential role of additional tools such as lung ultrasound to tailor and guide individualised respiratory support.