OBJECTIVES Inhaled nitric oxide (iNO) is an effective pulmonary vasodilator. However, the efficacy of iNO in former premature infants with established bronchopulmonary dysplasia (BPD) has not been studied. This study aimed to determine the efficacy of iNO in reducing pulmonary artery pressure in infants with severe BPD as measured by echocardiography. STUDY DESIGN Prospective, observational study enrolling infants born at less than 32 weeks gestation and in whom (1) iNO therapy was initiated after admission to our institution, or (2) at the outside institution less than 48 h before transfer and received an echocardiogram prior to iNO initiation, and (3) had severe BPD. Data were collected at three time-points: (1) before iNO; (2) 12-48 h after initiation of iNO; and (3) 48-168 h after initiation of iNO. The primary outcome was the effect of iNO on pulmonary artery pressure measured by echocardiography in patients with severe BPD between 48 and 168 h after initiating iNO therapy. RESULTS Of 37 enrolled, 81% had echocardiographic evidence of pulmonary arterial hypertension (PAH) before iNO and 56% after 48 h of iNO (p = 0.04). FiO2 requirements were significantly different between time-points (1) and (3) (p = 0.05). There were no significant differences between Tricuspid Annular Plane Systolic Excursion (TAPSE) Z-Scores, time to peak velocity: right ventricular ejection time (TPV:RVET), and ventilator changes. CONCLUSIONS Although we found a statistically significant reduction of PAH between time-point (1) and (3), future trials are needed to further guide clinical care.

中文翻译：

---

严重支气管肺发育不良婴儿吸入一氧化氮后肺动脉高压的超声心动图评估。

目的 吸入一氧化氮 (iNO) 是一种有效的肺血管扩张剂。然而，尚未研究 iNO 对患有支气管肺发育不良 (BPD) 的早产儿的疗效。本研究旨在确定 iNO 在降低超声心动图测量的严重 BPD 婴儿肺动脉压方面的功效。研究设计 前瞻性、观察性研究，纳入妊娠不足 32 周出生的婴儿，其中 (1) 入院后开始 iNO 治疗，或 (2) 在转院前不到 48 小时在外部机构接受超声心动图检查接受 iNO 起始治疗，并且 (3) 患有严重的 BPD。在三个时间点收集数据：（1）iNO 之前；(2) iNO起始后12-48小时；(3) iNO 启动后 48-168 小时。主要结局是 iNO 对开始 iNO 治疗后 48 至 168 小时内通过超声心动图测量的严重 BPD 患者肺动脉压力的影响。结果 在 37 名入组患者中，81% 在 iNO 之前有超声心动图证据显示肺动脉高压 (PAH)，56% 在 iNO 48 小时后有超声心动图证据（p = 0.04）。FiO2 要求在时间点 (1) 和 (3) 之间显着不同 (p = 0.05)。三尖瓣环平面收缩期偏移 (TAPSE) Z 评分、达到峰值速度的时间：右心室射血时间 (TPV:RVET) 和呼吸机变化之间没有显着差异。结论 尽管我们发现在时间点 (1) 和 (3) 之间 PAH 的发生率在统计学上显着降低，但仍需要未来的试验来进一步指导临床护理。