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BackgroundThe use of Nasal Continuous Positive Airway Pressure Ventilation (NCPAP) has begun to increase and is progressively replacing conventional mechanical ventilation (MV), becoming the cornerstone treatment for newborn respiratory distress syndrome (RDS). Howerver, NCPAP use in Lower-Middle Income Countries (LMICs) is poor. Moreover, bubble NCPAP (bNCPAP), for efficacy, cost effectiveness, and ease of use, should be the primary assistance technique employed in newborns with RDS.Objective: To measure the impact on in-hospital newborn mortality of using a bNCPAP device as the first intervention on newborns requiring ventilatory assistance.MethodsDesign: Prospective pre-intervention and post-intervention study.Setting: The largest Neonatal Intensive Care Unit (NICU) in Nicaragua.Participants: In all, 230 (2006) and 383 (2008) patients were included.Intervention: In May 2006, a strategy was introduced to promote the systematic use of bNCPAP to avoid intubation and MV in newborns requiring ventilatory assistance. Data regarding gestation, delivery, postnatal course, mortality, length of hospitalisation, and duration of ventilatory assistance were collected for infants assisted between May and December 2006, before the project began, and between May and December 2008, two years afterwards.Outcome measures: The pre- vs post-intervention proportion of newborns who died in-hospital was the primary end point. Secondary endpoints included rate of intubation and duration of NICU stay.ResultsSignificant differences were found in the rate of intubation (72 vs 39%; p < 0.0001) and the proportion of patients treated exclusively with bNCPAP (27% vs 61%; p <0.0001). Mortality rate was significantly reduced (40 vs 23%; p < 0.0001); however, an increase in the mean duration of NICU stay was observed (14.6 days in 2006 and 17.5 days in 2008, p = 0.0481).The findings contribute to the evidence that NCPAP, particularly bNCPAP, is the first-line standard of care for efficacy, cost effectiveness, and ease of use in newborns with respiratory distress in LMICs.ConclusionsThis is the first extensive survey performed in a large NICU from a LMICs, proving the efficacy of the systematic use of a bNCPAP device in reducing newborn mortality. These findings are an incentive for considering bNCPAP as an elective strategy to treat newborns with respiratory insufficiency in LMICs.

We asked 1) whether newborn rats respond to chronic hypercapnia with a persistent increase in ventilation and 2) whether changes in lung mass were accompanying the respiratory adaptation to chronic hypercapnia, as previously observed during neonatal chronic hypoxia. Five litters of rats were kept in 7% CO2 (with 21% O2) from day 1 to 7 after birth (CO2exp) and compared with six litters of control rats growing in normocapnia-normoxia (C). Body weight was similar between the two groups. Ventilation, measured by flow plethysmography, increased in CO2exp from day 2 and remained steadily elevated, and at day 7 it almost doubled (174%) the C value because of the large increase in tidal volume and mean inspiratory flow (192 and 189%, respectively) with no changes in respiratory frequency. Two days after return to normocapnia, ventilation was still 33% higher than in C; at this time, acute exposure to hypercapnia increased ventilation relatively less in the CO2exp than in C because of a lower increase in tidal volume. Neither the lung weight-to-body weight nor the heart weight-to-body weight ratios increased in CO2exp. We conclude that 1) chronic hypercapnia in newborn rats induces a steady increase in ventilation, which persists at least 2 days after return to normocapnia with a reduction in the acute response to CO2, and 2) hyperventilation per se is not the cause of the increased lung mass observed during chronic neonatal hypoxia.