Feasibility and Effect of Physiological-Based CPAP in Preterm Infants at Birth.

Preterm infants are commonly supported with 5-8 cmHO CPAP. However, animal studies demonstrate that high initial CPAP levels (12-15 cmHO) which are then reduced (termed physiological based (PB)-CPAP), improve lung aeration without adversely affecting cardiovascular function. We investigated the feasibility of PB-CPAP and the effect in preterm infants at birth. Preterm infants (24-30 weeks gestation) were randomized to PB-CPAP or 5-8 cmHO CPAP for the first 10 min after birth. PB-CPAP consisted of 15 cmHO CPAP that was decreased when infants were stabilized (heart rate ≥100 bpm, SpO ≥85%, FiO ≤ 0.4, spontaneous breathing) to 8 cmHO with steps of ~2/3 cmHO/min. Primary outcomes were feasibility and SpO in the first 5 min after birth. Secondary outcomes included physiological and breathing parameters and short-term neonatal outcomes. Planned enrollment was 42 infants. The trial was stopped after enrolling 31 infants due to a low inclusion rate and recent changes in the local resuscitation guideline that conflict with the study protocol. Measurements were available for analysis in 28 infants (PB-CPAP = 8, 5-8 cmHO = 20). Protocol deviations in the PB-CPAP group included one infant receiving 3 inflations with 15 cmHO PEEP and two infants in which CPAP levels were decreased faster than described in the study protocol. In the 5-8 cmHO CPAP group, three infants received 4, 10, and 12 cmHO CPAP. During evaluations, caregivers indicated that the current PB-CPAP protocol was difficult to execute. The SpO in the first 5 min after birth was not different [61 (49-70) vs. 64 (47-74), = 0.973]. However, infants receiving PB-CPAP achieved higher heart rates [121 (111-130) vs. 97 (82-119) bpm, = 0.016] and duration of mask ventilation was shorter [0:42 (0:34-2:22) vs. 2:58 (1:36-6:03) min, = 0.020]. Infants in the PB-CPAP group required 6:36 (5:49-11:03) min to stabilize, compared to 9:57 (6:58-15:06) min in the 5-8 cmH2O CPAP group ( = 0.256). There were no differences in short-term outcomes. Stabilization of preterm infants with PB-CPAP is feasible but tailoring CPAP appeared challenging. PB-CPAP did not lead to higher SpO but increased heart rate and shortened the duration of mask ventilation, which may reflect faster lung aeration.