Research for the relationship between threshold of viability and fetal lung structure, and mechanism of fetal hypoplastic lungs

在日本及西方国家，20世纪90年代随着表面活性剂治疗、以高频振荡通气（HFO）为代表的新型机械通气方法、产前类固醇治疗等新的治疗方法的普及，极早产儿（ELBW）和甚早产儿（VLBW）的生存率得到了提高。日本儿科学会新生儿委员会每隔5年对日本新生儿重症监护室现状和新生儿死亡率的报告进行了全国范围内的ELBW和VLBW结果调查。在过去二十年中，出生时体重不足1,000克的婴儿死亡率从1980年的55.3%和1990年的28.2%显著下降到2000年的17.8%。有鉴于此，日本政府厚生劳动省于1991年1月将《产妇保护法》中关于生存能力门槛的定义从妊娠24周改为妊娠22周。在这一变化之后，日本的新生儿科医生越来越多地干预妊娠22-23周的分娩。迄今为止，自对妊娠22周出生的婴儿进行重症监护以来已经过去了15年，日本正在继续努力改善这类婴儿的预后。这个项目的目的是：1；为验证孕22周为生存能力阈值的试验1)孕21周流产胎儿肺成熟度分析2)孕22-23周出生婴儿短期预后的全国调查3)出生体重小于500克婴儿短期预后的全国调查4)早产儿和足月婴儿尿液类固醇谱分析。实验分析1)宫内感染与体外KL-6生成的关系2)气管内给药乳铁蛋白预防肺炎假单胞菌

In Japan as well as western countries, the survival rate of extremely premature infants (ELBW) and very premature infants (VLBW) improved in the 1990s with the spread of new treatment methods such as surfactant therapy, new methods of mechanical ventilation represented by high frequency oscillatory ventilation (HFO), and prenatal steroid therapy. The Committee on Newborn Infants, Japan Society of Pediatrics has performed nation-wide surveys on the outcomes of ELBW and VLBW for reports on the current status of NICU and neonatal mortality in Japan at 5-year intervals. The mortality rate of infants weighing less than 1,000 g at birth significantly declined in the previous two decades from 55.3% in 1980 and 28.2% in 1990 to 17.8% in 2000. In view of this, the Ministry of Health, Labour and Welfare of the Japanese government changed the definition of the threshold of viability in the Maternal Protection Law from 24 weeks of gestation to 22 weeks of gestation in January, 1991. After this change, neonatologists in Japan have increasingly intervened in deliveries at 22-23 weeks' of gestation. To date, 15years have passed since intensive care for infants born at 22weeks' gestation was undertaken and efforts to improve the prognosis of such infants are continuing in Japan. The purpose of this project was as follows :1.For test to validate 22 weeks gestation as threshold of viability1)the analysis lung maturation of fetuses aborted at 21 weeks gestation2)nation wide survey of short term prognosis born at 22-23 weeks gestation3)nation wide survey of short term outcome of infants born weighing less than 500 grams4)the analysis of urine steroid profile of preterm and term infants2.experimental analysis1)the relationship between intrauterine infection and KL-6 production in vitro2)intaratracheal administration of lactoferrin to prevent pseudomonas pneumonia