Divisions of Neonatal Medicine and
Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota; and.
Pediatrics. 2018 Mar;141(3). doi: 10.1542/peds.2017-3108. Epub 2018 Feb 9.
Inhaled nitric oxide (iNO) is increasingly prescribed to extremely premature neonates with respiratory distress syndrome (RDS). Most of this off-label use occurs during the first week of life. We studied this practice, hypothesizing that it would not be associated with improved survival.
We queried the Pediatrix Medical Group Clinical Data Warehouse to identify all neonates born at 22 to 29 weeks' gestation from 2004 to 2014. In our study sample, we included singletons who required mechanical ventilation for treatment of RDS and excluded those with anomalies. The primary outcome was death before discharge. Through a sequential risk set approach, each patient who received iNO during the first 7 days of life ("case patient") was matched by using propensity scores to a patient who had not received iNO at a chronological age before the case patient's iNO initiation age (defined as the index age for the matched pair). The association between iNO status and in-hospital mortality was evaluated in a Cox proportional hazards regression model by using age as the time scale with patients entering the risk set at their respective index age.
Among 37 909 neonates in our study sample, we identified 993 (2.6%) who received iNO. The 2 matched cohorts each contained 971 patients. We did not observe a significant association between iNO exposure and mortality (hazard ratio, 1.08; 95% confidence interval, 0.94-1.25; = .29).
Off-label prescription of iNO is not associated with reduced in-hospital mortality among extremely premature neonates with RDS.
吸入一氧化氮（iNO）越来越多地用于治疗患有呼吸窘迫综合征（RDS）的极早产儿。这种超说明书使用大多发生在生命的第一周。我们研究了这种做法，假设它不会与存活率提高相关。
我们查询了 Pediatrix Medical Group 临床数据仓库，以确定 2004 年至 2014 年间出生在 22 至 29 周之间的所有新生儿。在我们的研究样本中，我们纳入了需要机械通气治疗 RDS 的单胎新生儿，并排除了有异常的新生儿。主要结局是出院前死亡。通过连续风险集方法，在生命的前 7 天内接受 iNO 的每位患者（“病例患者”）都与未在病例患者的 iNO 起始年龄之前（定义为配对患者的索引年龄）接受 iNO 的患者通过倾向评分进行匹配。使用年龄作为时间尺度，在各自的索引年龄时进入风险集，在 Cox 比例风险回归模型中评估 iNO 状态与住院死亡率之间的关联。
在我们的研究样本中，有 37909 名新生儿，其中 993 名（2.6%）接受了 iNO。两组匹配队列各包含 971 名患者。我们没有观察到 iNO 暴露与死亡率之间存在显著关联（风险比，1.08；95%置信区间，0.94-1.25； =.29）。
对于患有 RDS 的极早产儿，超说明书使用 iNO 与降低住院死亡率无关。
