1/2 The Diaphragmatic Initiated Ventilatory Assist (DIVA) Trial

支气管肺发育不良（BPD）是早产最常见的并发症，也是儿童发病的主要呼吸道原因。BPD给家庭带来了沉重的负担，并增加了医疗保健的利用率。仅在美国，BPD每年的医疗费用就超过24亿美元。呼吸机诱导的肺损伤（VILI）是公认的BPD的重要因素。暴露于氧气和正压通气可导致未成熟早产儿肺发育停止和实质损伤。因为即使是短暂的正压通气也是有害的，避免有创插管机械通气是预防VILI和BPD长期后遗症的最广泛认可的策略。因此，使用呼吸机的时间和拔管成功率是治疗的重要终点。肺保护策略优先考虑对呼吸衰竭的早产儿进行无创呼吸支持，但持续气道正压通气（CPAP）治疗的失败率很高。在现有试验的荟萃分析中，同步和非同步无创正压通气（NIPPV）在预防早产儿拔管失败方面都优于CPAP。同步NIPPV与CPAP的效应值比非同步NIPPV与CPAP的效应值更强。然而，直到最近，在美国还没有FDA批准的为早产儿提供同步NIPPV的可靠方法，神经调节通气辅助（NAVA）是一种FDA批准的技术，是一种同步通气支持与婴儿呼吸驱动的新方法。这种有效的非侵入性同步与电膈活动相匹配，以提供与神经信号成比例的同步和准确的潮汐量。迄今为止，非侵入性NAVA （NIV-NAVA）对早产儿临床结局的临床影响尚未确定。在这些UG3/UH3和U24的集群应用中，我们提出了一项实用的、非盲的III期临床试验，在478名胎龄为24 0/7- 27 6/7周的极早产儿中进行，以确定与非同步NIPPV相比，NIV-NAVA是否能在机械通气拔管后5天内防止拔管失败。

Bronchopulmonary dysplasia (BPD) is the most common complication of prematurity and is the leading respiratory cause of childhood morbidity. BPD results in a significant burden to families and increased health care utilization. In the United States alone BPD accounts for over $2.4 billion in healthcare costs annually. Ventilator induced lung injury (VILI) an accepted and important contributor to BPD. Exposure to oxygen and positive pressure ventilation leads to developmental arrest and parenchymal injury in the immature preterm lung. Because even brief exposure to positive pressure ventilation is injurious, avoiding invasive intubated mechanical ventilation is the most widely acknowledged strategy to prevent VILI and the long-term sequela of BPD. Therefore, time on ventilators and rates of successful extubation are important endpoints of therapy. Lung protective strategies prioritize non-invasive respiratory support for preterm infants with respiratory failure, but failure rates of continuous positive airway pressure (CPAP) therapy are high. In meta-analysis of available trials, both synchronized and non-synchronized non-invasive positive pressure ventilation (NIPPV) are superior to CPAP for preventing extubation failure in preterm infants. A stronger effect size was observed for synchronized NIPPV vs. CPAP than for non-synchronized NIPPV vs. CPAP. However, until recently no FDA-approved reliable methods to provide synchronized NIPPV for preterm infants were available in the US Neurally Adjusted Ventilatory Assist (NAVA), an FDA approved technology, is a novel method to synchronize ventilatory support with infant respiratory drive. This effective non-invasive synchronization matches electrical diaphragmatic activity to deliver synchronized and accurate tidal volumes in proportion to the neural signal. To date, the clinical impact of non-invasive NAVA (NIV-NAVA) on clinical outcomes in preterm infants has not been established. In these clustered UG3/UH3 and U24 applications, we propose a pragmatic, unblinded, phase III clinical trial in 478 extremely preterm infants of 24 0/7- 27 6/7 weeks gestational age to determine if NIV-NAVA, compared with non-synchronized NIPPV, prevents extubation failure within 5 days of extubation from mechanical ventilation.