Supplementary Material for: Introduction of a Quality Improvement Bundle Is Associated with Reduced Exposure to Mechanical Ventilation in Very Preterm Infants

<b><i>Introduction:</i></b> Exposure to mechanical ventilation (MV) is a risk factor for bronchopulmonary dysplasia (BPD) in very preterm infants (VPTIs). We assessed the impact of a quality improvement (QI) bundle in VPTIs (&lt;32 week gestation) on exposure to MV. <b><i>Methods:</i></b> We introduced a QI bundle consisting of deferred cord clamping (DCC), nasal bubble continuous positive airway pressure (bCPAP) in the delivery room (DR), and minimally invasive surfactant therapy (MIST). We compared respiratory outcomes and neonatal morbidity in historical pre-QI (July–December 2017) and prospective post-QI (February–July 2019) cohorts (QICs) of VPTIs. We pre-specified an adjusted analysis to account for the effects of gestational age, sex, antenatal steroids, and any demographic data that significantly differed between cohorts. <b><i>Results:</i></b> The pre-QI and post-QICs included 87 and 98 VPTIs, respectively. The post-QIC had decreased rates of MV in the DR (adjusted odds ratio [aOR] 0.26, 95% confidence interval [CI] 0.09–0.71), in the first 72 h of life (aOR 0.27, 95% CI 0.11–0.62) and during admission (aOR 0.28, 95% CI 0.12–0.66). Rates of BPD, combined BPD/death, and BPD severity were similar. The post-QIC was less likely to be discharged with home oxygen (aOR 0.27, 95% CI 0.08–0.91). Necrotising enterocolitis grade ≥2 increased (aOR 19.01, 95% CI 1.93–188.6) in the post-QIC. <b><i>Conclusion:</i></b> In this rapid-cycle QI study, implementation of a QI bundle consisting of DCC, early nasal bCPAP, and MIST in VPTIs was associated with reduced rates of MV in the DR, in the first 72 h of life and during admission, and reduced need for home oxygen.

## 引言：
机械通气（Mechanical Ventilation, MV）暴露是极早早产儿（Very Preterm Infants, VPTIs）罹患支气管肺发育不良（Bronchopulmonary Dysplasia, BPD）的危险因素。本研究评估了质量改进（Quality Improvement, QI）包对妊娠<32周极早早产儿机械通气暴露的影响。

## 方法：
本研究引入了一套涵盖延迟脐带结扎（Deferred Cord Clamping, DCC）、产房（Delivery Room, DR）内经鼻气泡式持续气道正压通气（Nasal Bubble Continuous Positive Airway Pressure, bCPAP）与微创表面活性物质治疗（Minimally Invasive Surfactant Therapy, MIST）的质量改进方案。我们纳入极早早产儿的历史性前质量改进队列（2017年7月—12月）与前瞻性后质量改进队列（2019年2月—7月，QICs），对比两组的呼吸结局与新生儿发病情况。本研究预先设定校正分析模型，以控制胎龄、性别、产前糖皮质激素应用以及两组间存在显著差异的人口学特征的混杂影响。

## 结果：
前质量改进队列与后质量改进队列分别纳入87例和98例极早早产儿。后质量改进队列的产房机械通气率（校正比值比[adjusted odds ratio, aOR] 0.26，95%置信区间[confidence interval, CI] 0.09–0.71）、出生后最初72小时机械通气率（aOR 0.27，95%CI 0.11–0.62）以及住院期间机械通气率（aOR 0.28，95%CI 0.12–0.66）均显著降低。两组的支气管肺发育不良发生率、支气管肺发育不良/死亡联合结局发生率以及支气管肺发育不良严重程度均无显著差异。后质量改进队列出院时需家庭氧疗的比例显著更低（aOR 0.27，95%CI 0.08–0.91）。但后质量改进队列的≥2级坏死性小肠结肠炎发生率显著升高（aOR 19.01，95%CI 1.93–188.6）。

## 结论：
在这项快速循环质量改进研究中，为极早早产儿实施包含延迟脐带结扎、早期经鼻气泡式持续气道正压通气与微创表面活性物质治疗的质量改进方案，可显著降低产房、出生后最初72小时及住院期间的机械通气使用率，并减少家庭氧疗需求。