Compared with T-piece systems, the new system had a marked reduction in iWOB in bench tests. The feasibility trial did not reveal problems with usability or safety.

IntroductionAccess to inexpensive respiratory support to newborn infants improves survival in low-income countries. Standard bubble continuous positive airway pressure (CPAP) has been extensively used worldwide for more than 30 years. One project aimed at providing affordable CPAP is the Pumani system developed by Rice 360°. Compared to standard bubble CPAP the system has an unconventional design. The aim was to compare the Pumani system with two traditional bubble CPAP systems, focusing on in-vitro performance and safety.MethodsThe Pumani system was compared to traditional bubble CPAP from Fisher & Paykel (Auckland, New Zealand) and Diamedica (Devon, United Kingdom). The systems were tested using static flow resistance and simulated breathing for a range of fresh gas flows and submersion levels.ResultsThere were large differences between the Pumani CPAP and the conventional bubble CPAP systems. The Pumani system was not pressure stable, had high resistance and high imposed work of breathing. It was not possible to use submersion depth to adjust CPAP without accounting for fresh gas flow.DiscussionThe Pumani design is novel and not similar to any previously described CPAP system. The main mechanism for CPAP generation was resistance, not submersion depth. The system should therefore not be referred to as bubble CPAP. The clinical consequences of its pressure instability and high imposed work of breathing are not known and trials on outcome and safety are needed.

BackgroundThe original bubble continuous positive airway pressure (bCPAP) design has wide-bore tubing and a low-resistance interface. This creates a stable airway pressure that is reflected by the submersion depth of the expiratory tubing. Several systems with alterations to the original bCPAP design are now available. Most of these are aimed for use in low-income and middle-income countries and have not been compared with the original design.ObjectiveWe identified three major alterations to the original bCPAP design: (1) resistance of nasal interface, (2) volume of dead space and (3) diameter of expiratory tubing. Our aim was to study the effect of these alterations on CPAP delivery and work of breathing in a mechanical lung model. Dead space should always be avoided and was not further tested.MethodsThe effect of nasal interface resistance and expiratory tubing diameter was evaluated with simulated breathing in a mechanical lung model without interface leakage. The main outcome was delivered CPAP and imposed work of breathing.ResultsHigh-resistance interfaces and narrow expiratory tubing increased the work of breathing. Additionally, narrow expiratory tubing resulted in higher CPAP levels than indicated by the submersion depth.ConclusionOur study shows the significant effect on CPAP delivery and imposed work of breathing when using high-resistance interfaces and narrow expiratory tubing in bCPAP systems. New systems should include low-resistance interfaces and wide-bore tubing and be compared with the original bCPAP. Referring to all systems that bubble as bCPAP is misleading and potentially hazardous.

IMPORTANCEEstablishing stable breathing is a key event for preterm infants after birth. Delivery of pressure-stable continuous positive airway pressure and avoiding face mask use could be of importance in the delivery room.OBJECTIVE To determine whether using a new respiratory support system with low imposed work of breathing and short binasal prongs decreases delivery room intubations or death compared with a standard T-piece system with a face mask. DESIGN, SETTING, AND PARTICIPANTSIn this unblinded randomized clinical trial, mothers threatening preterm delivery before week 28 of gestation were screened. A total of 365 mothers were enrolled, and 250 infants were randomized before birth and 246 liveborn infants were treated. The trial was conducted in 7 neonatal intensive care units in 5 European countries from March 2016 to May 2020. The follow-up period was 72 hours after intervention.INTERVENTIONS Infants were randomized to either the new respiratory support system with short binasal prongs (n = 124 infants) or the standard T-piece system with face mask (n = 122 infants). The intervention was providing continuous positive airway pressure for 10 to 30 minutes and positive pressure ventilation, if needed, with the randomized system. MAIN OUTCOMES AND MEASURESThe primary outcome was delivery room intubation or death within 30 minutes of birth. Secondary outcomes included respiratory and safety variables. RESULTSOf 246 liveborn infants treated, the mean (SD) gestational age was 25.9 (1.3) weeks, and 127 (51.6%) were female. A total of 41 infants (33.1%) receiving the new respiratory support system were intubated or died in the delivery room compared with 55 infants (45.1%) receiving standard care. The adjusted odds ratio was statistically significant after adjusting for stratification variables (adjusted odds ratio, 0.53; 95% CI, 0.30-0.94; P = .03). No significant differences were seen in secondary outcomes or safety variables. CONCLUSIONS AND RELEVANCEIn this study, using the new respiratory support system reduced delivery room intubation in extremely preterm infants. Stabilizing preterm infants with a system that has low imposed work of breathing and binasal prongs as interface is safe and feasible.