Mercier J C, Lacaze T, Storme L, Rozé J C, Dinh-Xuan A T, Dehan M
Department of Pediatrics, Hôpital Robert-Debré, Paris, France.
Eur J Pediatr. 1998 Sep;157(9):747-52. doi: 10.1007/s004310050928.
Inhaled nitric oxide (iNO) has been shown to improve oxygenation in severe persistent pulmonary hypertension of the newborn (PPHN). However, PPHN is often associated with various lung diseases. Thus, response to iNO may depend upon the aetiology of neonatal acute respiratory failure. A total of 150 (29 preterm and 121 term) newborns with PPHN were prospectively enrolled on the basis of oxygenation index (OI) higher than 30 and 40, respectively. NO dosage was stepwise increased (10-80 ppm) during conventional mechanical or high-frequency oscillatory ventilation while monitoring the oxygenation. Effective dosages ranged from 5 to 20 ppm in the responders, whereas iNO levels were unsuccessfully increased up to 80 ppm in the nonresponders. Within 30 min of iNO therapy, OI was significantly reduced in either preterm neonates (51+/-21 vs 23+/-17, P < .0001) or term infants with idiopathic or acute respiratory distress syndrome (45+/-20 vs 20+/-17, P < .0001), 'idiopathic' PPHN (39+/-14 vs 14+/-9, P < .0001), and sepsis (55+/-25 vs 26+/-20, P < .0001) provided there was no associated refractory shock. Improvement in oxygenation was less significant and sustained (OI=41+/-16 vs 28+/-18, P < .001) in term neonates with meconium aspiration syndrome and much less (OI=58+/-25 vs 46+/-32, P < .01) in those with congenital diaphragmatic hernia. Only 21 of the 129 term newborns (16%) required extracorporeal membrane oxygenation (57% survival). Survival was significantly associated with the magnitude in the reduction in OI at 30 min of iNO therapy, a gestational age > or =34 weeks, and associated diagnosis other than congenital diaphragmatic hernia. Conclusion, iNO improves the oxygenation in most newborns with severe hypoxaemic respiratory failure including preterm neonates. However, response to iNO is disease-specific. Furthermore, iNO when combined with adequate alveolar recruitment and limited barotrauma using exogenous surfactant and HFOV may obviate the need for extracorporeal membrane oxygenation in many term infants.
吸入一氧化氮（iNO）已被证明可改善新生儿重症持续性肺动脉高压（PPHN）的氧合情况。然而，PPHN常与多种肺部疾病相关。因此，对iNO的反应可能取决于新生儿急性呼吸衰竭的病因。共有150例（29例早产儿和121例足月儿）PPHN新生儿根据氧合指数（OI）分别高于30和40被前瞻性纳入研究。在常规机械通气或高频振荡通气期间，逐步增加NO剂量（10 - 80 ppm），同时监测氧合情况。有反应者的有效剂量范围为5至20 ppm，而无反应者的iNO水平即使增至80 ppm也未成功改善。在iNO治疗30分钟内，无论是早产儿（51±21对23±17，P <.0001），还是患有特发性或急性呼吸窘迫综合征的足月儿（45±20对20±17，P <.0001）、“特发性”PPHN（39±14对14±9，P <.0001）和败血症（55±25对26±20，P <.0001），只要没有相关的难治性休克，OI均显著降低。胎粪吸入综合征的足月儿氧合改善不太显著且持续时间较短（OI = 41±16对28±18，P <.001），先天性膈疝患儿的改善则更不明显（OI = 58±25对46±32，P <.01）。129例足月儿中只有21例（16%）需要体外膜肺氧合（存活率为57%）。存活率与iNO治疗30分钟时OI降低的幅度、胎龄≥34周以及除先天性膈疝以外的相关诊断显著相关。结论，iNO可改善大多数患有严重低氧性呼吸衰竭的新生儿（包括早产儿）的氧合情况。然而，对iNO的反应具有疾病特异性。此外，iNO与使用外源性表面活性剂和高频振荡通气进行充分的肺泡复张及有限的气压伤相结合，可能使许多足月儿无需进行体外膜肺氧合。
