探讨新生儿重型胎粪吸入综合征(MAS)合并急性肺损伤(ALI)的临床特点及其相关防治措施，以利于进一步降低新生儿病死率。

选择2009年9月至2011年3月在本院新生儿科住院治疗的56例重型MAS合并ALI患儿为研究对象。按照动脉血氧分压(PaO₂)与吸入氧气分数(FiO₂)比值(PaO₂/FiO₂)，将其分为PaO₂/FiO₂≤100组(n＝13)和PaO₂/FiO₂>100组(n＝43)。对两组进行对比分析(本研究遵循的程序符合本院人体试验委员会制定的伦理学标准，得到该委员会批准，分组征得受试对象监护人的知情同意，并与其签署临床研究知情同意书)。两组患儿分娩方式、性别分布、出生体重等比较，差异无统计学意义(χ²＝1.5, 2.7, 1.9；P>0.05)。

重型MAS合并ALI患儿中，两组患儿上机时间比较[(4.92±5.22) h vs. (3.43±3.24) h]，差异无统计学意义(P>0.05)；而PaO₂/FiO₂≤100组患儿依赖呼吸机治疗时间比较[(62.15±27.61) h vs. (42.12±19.62) h]，差异有统计学意义(P<0.05)。PaO₂/FiO₂≤100组存在更严重的低氧血症、高碳酸血症及明显的肺顺应性下降(P<0.01)，X射线胸部摄片常见双肺透亮度下降(χ²＝5.28，r＝1；P<0.05)，甚至出现支气管充气征，更易合并新生儿持续性肺动脉高压(PPHN)(P＝0.01)。重型MAS合并ALI患儿中，PaO₂/FiO₂≤100组入院后，均予高频振荡通气(HFOV)治疗，10例(76.9%，10/13)接受气管内注入猪肺磷脂肺表面活性物质(PS)治疗，3例(23.1%，3/13)接受吸入一氧化氮(iNO)治疗，上机治疗(8~12)h后血气分析结果显示氧合、通气功能得到明显改善(P<0.001)。

MAS合并ALI患儿存在严重的通气、氧合功能障碍。对其联合HFOV，注入PS和iNO治疗，可更有效地改善氧合。但是否为其最有前景的治疗模式，尚需多中心、大样本的随机对照研究进一步证实。

To investigate clinical characteristics of severe meconium aspiration syndrome (MAS) complicated with acute lung injury (ALI) and measures for the prevention and treatment of MAS complicated with ALI in order to reduce mortality.

A total of 56 neonates with a diagnosis of severe MAS complicated with ALI were admitted to our Neonatal Department from September 2009 to March 2011 and divided into two groups based on PaO₂/FiO₂ level: PaO₂/FiO₂≤100 group (n=13) and PaO₂/FiO₂>100 group (n=43). The study protocol was approved by the Ethical Review Board of Investigation in Human Being of Maternal and Child Health Hospital of Xiamen City. Informed consent was obtained from the parents of each participating neonate. No significant differences were found between two groups in the methods of delivery, gender distribution and birth weight of neonate (χ²=1.5, 2.7, 1.9; P>0.05).

Hypoxemia, hypercapnia and decreased lung compliance occurred more serious in neonates of severe MAS complicated with ALI(PaO₂/FiO₂≤100 group vs. PaO₂/FiO₂≥100 group)(P<0.001). Chest radiographs commonly indicated pulmonary parenchymal opacities and air bronchograms(χ²=5.28, r=1; P<0.05). These cases required long-term ventilator therapy [(62.15±27.61) h vs. (42.12±19.62) h, P<0.05] and often complicated with persistent pulmonary hypertension of the newborn(PPHN)(P=0.01). The 13 neonates of severe MAS complicated with ALI(PaO₂/FiO₂≤100 group) were treated with high frequency oscillatory ventilation (HFOV) after admission.Among them, 10 cases(76.9%, 10/13) were treated with PS by endotracheal intubation and 3 (23.1%, 3/13)were treated with inhalation nitrogen monoxide(iNO). After 8-12 hours' treatment with ventilation, arterial blood analysis showed significantly improved oxygenation and alveolar ventilation(P<0.001).

The newborns of severe MAS complicated with ALI showed severe hypoventilation and dysfunction of oxygenation. Combined application of HFOV, PS and iNO strategy can effectively improve oxygenation. But whether it could be the most promising treatment for severe MAS complicated with ALI, it still need multi-center, large-sample random control trials to confirm.