Aikio O, Pokela M L, Hallman M
Department of Pediatrics, University of Oulu, Finland.
Acta Paediatr. 2002;91(10):1078-86. doi: 10.1080/080352502760311584.
Nitric oxide (NO) is an important mediator required for neonatal pulmonary circulatory adaptation and for pulmonary defence. Both deficient and excessive NO production have been proposed to play a role in neonatal lung disease. This study aimed to establish a method that allows direct measurement of exhaled and nasal NO concentrations in newborn infants who require intubation and ventilation.
A rapid-response chemiluminescence NO analyser was used. Gas was sampled from the endotracheal intubation tube, and tidal volumes and flow rates were measured. The nasal NO was sampled from the non-intubated nostril. The accuracy of the method was validated using a lung model. NO levels from six preterm and six term/near-term newborns were studied. Measurements were performed on a daily basis during the first week.
An expiration >0.2 s in duration with a flow rate >1.7 ml s(-1) could be accurately analysed for the presence of >1 parts per billion of NO. The very preterm infants with neonatal lung disease had a different postnatal NO output pattern from the lower and upper airways compared with the ventilated term/near-term infants.
A novel method for measurement of exhaled NO of an intubated newborn is presented. The possible association of exhaled NO concentration with the development of chronic lung disease remains to be studied.
一氧化氮（NO）是新生儿肺循环适应和肺部防御所需的重要介质。NO生成不足和过量均被认为与新生儿肺部疾病有关。本研究旨在建立一种方法，用于直接测量需要插管和通气的新生儿呼出气体和鼻腔内的NO浓度。
使用快速响应化学发光NO分析仪。从气管内插管采集气体，并测量潮气量和流速。从未插管的鼻孔采集鼻腔内的NO。使用肺部模型验证该方法的准确性。研究了6例早产儿和6例足月儿/近足月儿的NO水平。在第一周内每天进行测量。
对于持续时间>0.2秒且流速>1.7毫升/秒的呼气，能够准确分析其中十亿分之一以上的NO的存在情况。与接受通气的足月儿/近足月儿相比，患有新生儿肺部疾病的极早产儿出生后下呼吸道和上呼吸道的NO输出模式有所不同。
提出了一种测量插管新生儿呼出气体中NO的新方法。呼出气体中NO浓度与慢性肺部疾病发展之间的可能关联仍有待研究。
