Baraldi E, Dario C, Ongaro R, Scollo M, Azzolin N M, Panza N, Paganini N, Zacchello F
Departments of Pediatrics and Anesthesia and Intensive Care, University of Padova, School of Medicine, Padova, Italy.
Am J Respir Crit Care Med. 1999 Apr;159(4 Pt 1):1284-8. doi: 10.1164/ajrccm.159.4.9807084.
While it is known that exhaled nitric oxide (ENO) is increased in adults and school children with asthma exacerbation probably as an expression of disease activity, no studies have investigated whether this phenomenon also occurs in infants and young children with recurrent wheeze exacerbation. We measured ENO in 13 young children (mean age 20.2 mo) with recurrent wheeze (Group 1) during an acute episode and after 5 d of oral prednisone therapy. ENO was measured also in nine healthy control subjects (Group 2) (mean age 16.9 mo) and in six children with a first-time viral wheezy episode (Group 3) (mean age 11 mo). To measure ENO, infants inhaled NO-free air via a face mask from a reservoir and, through a nonrebreathing valve, exhaled in a collecting bag that was analyzed by chemiluminescence. To address the question of whether the levels of ENO collected in the bag are a reflection of the pulmonary airway, ENO determinations were performed in two healthy infants before and after tracheal intubation for elective surgery. During the acute episode of wheezing the mean (+/- SEM) value of ENO in children with recurrent wheeze (Group 1) was 14.1 +/- 1.8 ppb, almost threefold higher than in healthy control subjects (5.6 +/- 0.5 ppb, p < 0.001). After steroid therapy we found a mean fall of 52% in ENO (5.9 +/- 0.7 ppb, p < 0.01) compared with baseline values. ENO values measured before and after intubation in two infants were 6 ppb and 5 ppb in one child and 7 ppb and 6 ppb in the other one. The mean value of ENO of children with first-time wheeze (Group 3) was 8.3 +/- 1.3 ppb, significantly lower (p < 0.05) than the value of children with recurrent wheeze (Group 1). In conclusion, we describe a method to measure ENO in young children and show that infants with recurrent wheeze have elevated levels of ENO during exacerbation that rapidly decrease after steroid therapy. This suggests that, in these children, airway inflammation could be present at a very early stage.
虽然已知哮喘发作时成人和学龄儿童呼出的一氧化氮（ENO）会增加，这可能是疾病活动的一种表现，但尚无研究调查这种现象是否也发生在反复喘息发作的婴幼儿中。我们测量了13名反复喘息的幼儿（平均年龄20.2个月）（第1组）在急性发作期间以及口服泼尼松治疗5天后的ENO水平。还测量了9名健康对照受试者（第2组）（平均年龄16.9个月）和6名首次出现病毒性喘息发作的儿童（第3组）（平均年龄11个月）的ENO水平。为了测量ENO，婴儿通过面罩从储气罐吸入无NO的空气，并通过一个非重复呼吸阀向一个收集袋呼气，该收集袋通过化学发光法进行分析。为了解决收集袋中收集的ENO水平是否反映肺气道的问题，在两名健康婴儿择期手术气管插管前后进行了ENO测定。在喘息急性发作期间，反复喘息儿童（第1组）的ENO平均（±SEM）值为14.1±1.8 ppb，几乎是健康对照受试者（5.6±0.5 ppb，p<0.001）的三倍。类固醇治疗后，我们发现ENO平均下降了52%（5.9±0.7 ppb，p<0.01），与基线值相比。两名婴儿插管前后测量的ENO值，一名儿童为6 ppb和5 ppb，另一名儿童为7 ppb和6 ppb。首次喘息儿童（第3组）的ENO平均值为8.3±1.3 ppb，显著低于反复喘息儿童（第1组）的值（p<0.05）。总之，我们描述了一种测量幼儿ENO的方法，并表明反复喘息的婴儿在发作期间ENO水平升高，类固醇治疗后迅速下降。这表明，在这些儿童中，气道炎症可能在很早阶段就存在。
