OBJECTIVES: To determine whether nasal continuous positive airway pressure (NCPAP), applied immediately after extubation of preterm infants, reduces the incidence of extubation failure and the need for additional ventilatory support, without clinically important adverse events.

SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, and trial registries on 22 September 2023 using a revised strategy. We searched conference abstracts and the reference lists of included studies and relevant systematic reviews.

SELECTION CRITERIA: Eligible trials employed random or quasi-random allocation of preterm infants undergoing extubation. Eligible comparisons were NCPAP (delivered by any device and interface) versus head box oxygen, extubation to room air, or any other form of low-pressure supplemental oxygen. We grouped the comparators under the term no continuous positive airway pressure (no CPAP).

DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the risk of bias and extracted data from the included studies. Where studies were sufficiently similar, we performed a meta-analysis, calculating risk ratios (RRs) with their 95% confidence intervals (CIs) for dichotomous data. For the primary outcomes that showed an effect, we calculated the number needed to treat for an additional beneficial outcome (NNTB). We used the GRADE approach to assess the certainty of the evidence for clinically important outcomes.

MAIN RESULTS: We included nine trials (with 726 infants) in the quantitative synthesis of this updated review. Eight studies were conducted in high-income countries between 1982 and 2005. One study was conducted in Chile, which was classified as upper-middle income at the time of the study. All studies used head box oxygen in the control arm. Risk of bias was generally low. However, due to the inherent nature of the intervention, no studies incorporated blinding. Consequently, the neonatal intensive care unit staff were aware of the assigned group for each infant, and we judged all studies at high risk of performance bias. However, we assessed blinding of the outcome assessor (detection bias) as low risk for seven studies because they used objective criteria to define both primary outcomes. NCPAP compared with no CPAP may reduce the risk of extubation failure (RR 0.62, 95% CI 0.51 to 0.76; risk difference (RD) -0.17, 95% -0.23 to -0.10; NNTB 6, 95% CI 4 to 10; I2 = 55%; 9 studies, 726 infants; low-certainty evidence) and endotracheal reintubation (RR 0.79, 95% 0.64 to 0.98; RD -0.07, 95% CI -0.14 to -0.01; NNTB 15, 95% CI 8 to 100; I2 = 65%; 9 studies; 726 infants; very low-certainty evidence), though the evidence for endotracheal reintubation is very uncertain. NCPAP compared with no CPAP may have little or no effect on bronchopulmonary dysplasia, but the evidence is very uncertain (RR 0.89, 95% CI 0.47 to 1.68; RD -0.03, 95% CI -0.22 to 0.15; 1 study, 92 infants; very low-certainty evidence). No study reported neurodevelopmental outcomes.

DISCUSSION: This review presents the significant clinical aspects and variables of ventilation management, the potential risks associated with suboptimal ventilation management, and a review of the major recent attempts to improve ventilation in the context of these variables. The unique aspect of this review is a focus on these key elements relevant to engineering new approaches. In particular, the need for ventilation strategies which consider, and directly account for, the significant differences in patient condition, disease etiology, and progression within patients is demonstrated with the subsequent requirement for optimal ventilation strategies to titrate for patient- and time-specific conditions.

METHODS AND DESIGN: The CURE RCT compares two groups of patients requiring invasive MV with a partial pressure of arterial oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio ≤ 200; one criterion of the Berlin consensus definition of moderate (≤ 200) or severe (≤ 100) ARDS. All patients are ventilated using pressure controlled (bi-level) ventilation with tidal volume = 6-8 ml/kg. Patients randomised to the control group will have PEEP selected per standard practice (SPV). Patients randomised to the intervention will have PEEP selected based on a minimal elastance using a model-based computerised method. The CURE RCT is a single-centre trial in the intensive care unit (ICU) of Christchurch hospital, New Zealand, with a target sample size of 320 patients over a maximum of 3 years. The primary outcome is the area under the curve (AUC) ratio of arterial blood oxygenation to the fraction of inspired oxygen over time. Secondary outcomes include length of time of MV, ventilator-free days (VFD) up to 28 days, ICU and hospital length of stay, AUC of oxygen saturation (SpO2)/FiO2 during MV, number of desaturation events (SpO2 oxygenation) and hospital and 90-day mortality.

DISCUSSION: The CURE RCT is the first trial comparing significant clinical outcomes in patients with ARDS in whom PEEP is selected at minimum elastance using an objective model-based method able to quantify and consider both inter-patient and intra-patient variability. CURE aims to demonstrate the hypothesized benefit of patient-specific PEEP and attest to the significance of real-time monitoring and decision-support for MV in the critical care environment.

Methods: This study was carried out at the Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia, between June 2016 and July 2017. Bone marrow cells were isolated from nine mice and cultured in a growth medium. Various concentrations of NAC between 0.125-2 μM were added to the culture for 48 hours; these cells were then compared to non-supplemented cells harvested from the remaining three mice as the control group. A trypan blue exclusion test was performed to determine cell viability, while intracellular ROS levels and genotoxicity were determined by hydroethidine staining and comet assay, respectively. The lineage commitment potential of erythroid, myeloid and pre-B-lymphoid progenitor cells was evaluated via colony-forming cell assay.

Results: NAC supplementation at 0.25, 0.5 and 2 μM significantly increased cell viability (P <0.050), while intracellular ROS levels significantly decreased at 0.25 and 0.5 μM (P <0.050). Moreover, DNA damage was significantly reduced at all NAC concentrations (P <0.050). Finally, the potential lineage commitment of the cells was not significantly affected by NAC supplementation (P >0.050).