北京地区学龄儿童呼出气一氧化氮调查分析

目的 了解北京地区学龄儿童呼出气一氧化氮(eNO)水平.方法 选择北京市11-18岁在校学生,采用过敏件疾病与哮喘的国际间对比研究调查问卷,通过填写问卷及现场体检对儿童进行分组(正常儿童组及曾患不同疾病儿童组),检测eNO水平、峰流速及过敏原.结果 共筛选出正常儿童395名,男177名,女218名.不同性别正常儿童eNO差异无统计学意义(P均>0.05),但与其年龄呈正相关(男性P=0.008,女性P=0.05),在男性与其身高呈正相关(P=0.02).11～14岁、14～18岁正常儿童eNO几何均数(G)分别为11.22、14.13 ppb(ppb=10~9),其95%正常值范围分别为4.17～30.20 ppb、5.50～36.31 ppb.曾患哮喘/喘息(68例)和曾患过敏性鼻炎(96例)儿童eNO几何均数分别是19.05 ppb、14.79 ppb,与正常儿童差异有统计学意义(P分别为0.001、0.008).过敏原皮肤点刺检查阳性与阴性儿童eNO几何均数分别为16.98 ppb、11.75 ppb,两组间差异有统计学意义(P=0.001).结论 北京地区11～18岁正常学龄儿童eNO随年龄波动于10.72～13.80ppb,与年龄、身高呈正相关,与性别无关.喘息性疾病、过敏性鼻炎患儿以及特应性个体eNO水平显著增加.     

哮喘患儿呼出气一氧化氮及外周血嗜酸粒细胞的变化

目的：检测支气管哮喘（AS）,AS合并过敏性鼻炎（AS/AR）及慢性咳嗽变异性哮喘（CVA）患儿中呼出气一氧化氮（eNO）和外周血嗜酸粒细胞（EOS）的水平及两者的相关性,以探讨eNOS检测在AS儿童中的应用。方法：采用电化学法对5～14岁患有AS（n=12）、AS/AR（n=29）、CVA（n=10）的患儿进行eNO测定,同时测定EOS及一秒钟用力呼气容积占预计值百分比（FEV1％）。30例无特异性疾病史和家族过敏史,且近两周无急性呼吸道感染史的儿童作为对照组。结果：AS,AS/AR,CVA 3组eNO和EOS水平均高于对照组（P＜0.01）;AS/AR组eNO（50.3±6.7 ppb）和EOS水平（5.9±4.2×109）高于AS组（30.5±8.8 ppb,4.2±3.2×109）及CVA组（26.0±3.2 ppb,3.7±6.9×109）（均P＜0.05）,而AS、CVA组间差异无显著性;AS组eNO与EOS呈正相关（r＝0.51,P＜0.05）,但与FEV1无相关性（r＝0.144,P＞0.05）。结论：eNO在过敏性体质中高表达,且eNO可以反映AS患者气道嗜酸性炎症水平。［中国当代儿科杂志,2009,11（12）：986-988］     

在社区儿童哮喘诊断与管理中呼出气一氧化氮测定应用研究

目的 探讨呼出气一氧化氮（exhaled nitric oxide, eNO）体积分数在社区儿童的改变及对哮喘诊断与管理的价值。方法 2011年10月至2011年12月对来自北京西城区小学的7~12岁132例非哮喘儿童和93例哮喘儿童进行eNO测定、肺功能检测、过敏原皮肤点刺检查（skin prick test, SPT）以及病史询问和常规体检,观察eNO在社区非哮喘儿童和哮喘儿童的改变、影响因素及与临床情况的相关性。结果 非哮喘儿童与哮喘儿童eNO体积分数分别为（11.63±1.88）×10-9和（19.68±2.31）×10-9,其差异有统计学意义（P < 0.01）。在非哮喘儿童中,有鼻炎儿童的eNO为（17.49±2.02）×10-9,显著高于无鼻炎儿童（10.42±1.76）×10-9;特应性儿童的eNO为（16.12±1.98）×10-9,显著高于非特应性儿童（9.60±1.66）×10-9,差异均有统计学意义（P均 < 0.01）。在哮喘儿童中,伴有鼻炎与不伴有鼻炎儿童,其eNO水平分别为（19.54±2.31）×10-9、（20.09±2.25）×10-9,差异无统计学意义;但特应性儿童eNO水平显著高于非特应性儿童［分别为（23.06±2.18）×10-9、（8.75±1.86）×10-9,P < 0.01］;哮喘未控制儿童eNO为（25.09±2.31）×10-9,显著高于哮喘控制儿童［（17.21±2.22）×10-9,P < 0.05］;曾使用吸入激素与未曾使用吸入激素儿童,其eNO水平差异无统计学意义。无论是非哮喘儿童,还是哮喘儿童,其eNO水平与肺功能各参数间均无相关性。结论 eNO在社区特应性哮喘儿童中显著升高,并与哮喘控制与否有关。特应性是影响eNO水平的突出因素。在社区儿童中测定eNO有利于对儿童哮喘的进行早期诊断和分型,全面了解其过敏情况,从而改善哮喘的管理。     

以225名健康儿童建立呼出气一氧化氮正常值

目的：探讨6~14岁儿童呼出气一氧化氮（FeNO）正常值范围及其影响因素。方法：选取苏州市6~14岁在校儿童进行问卷调查及FeNO、肺功能、外周血嗜酸粒细胞（EOS）计数的检测,筛选出健康儿童建立FeNO正常值。FeNO的测定采用电化学法,根据美国胸科学会/欧洲呼吸学会指南进行操作。分析性别、年龄、身高、体重、外周血EOS计数、肺功能和FeNO的相关性。结果：参与调查的450名儿童中符合纳入标准者225名（男生107名,女生118名）进入分析。FeNO值呈偏态分布,经自然对数转换后呈正态分布。FeNO平均值为11 ppb(95%CI:5~28 ppb）,最小值<5 ppb,最大值为83 ppb。男生FeNO平均值为11 ppb(95%CI:5~31 ppb）,女生FeNO平均值为11 ppb(95%CI:5~25 ppb）。FeNO与外周血EOS计数相关性最为显著（r=0.291,P<0.001）,与身高（r=0.148, P=0.027）和FEV1（r=0.138, P=0.038）显著相关;>9岁儿童FeNO显著高于≤9岁儿童（P=0.002）;FeNO与性别、体重、BMI、FEV1/FVC无显著相关性。结论：苏州地区6~14岁儿童FeNO正常参考值为5~28 ppb;FeNO水平与外周血EOS计数、身高、FEV1显著相关。     

不同控制水平的哮喘患儿呼出气一氧化氮浓度水平及其临床意义

目的：研究呼出气一氧化氮浓度（fractional nitric oxide concentration in exhaled breath, FeNO）测定技术在辅助评价儿童哮喘控制水平方面的应用价值。方法：将226例哮喘患儿分为哮喘控制组（n=86）、部分控制组（n=63）和未控制组（n=77）,90例健康儿童为对照组。采用瑞典尼尔斯（NIOX）呼出一氧化氮测定仪测定哮喘患儿和健康对照儿童FeNO浓度。结果：对照组儿童FeNO浓度为14±6 ppb,控制组为29±26 ppb,部分控制组为32±30 ppb,未控制组为40±32 ppb,3组哮喘患儿的FeNO浓度均高于对照组（P<0.05）;哮喘未控制组患儿FeNO浓度高于控制组（P<0.05）;哮喘部分控制组FeNO浓度与未控制和控制组之间差异无统计学意义。结论：哮喘患儿FeNO水平显著高于健康儿童,且与哮喘控制程度相关。     

122例门诊儿童哮喘临床分析

目的：了解深圳地区儿童哮喘发病情况和过敏原及肺功能变化。方法：应用皮肤点刺试验测定儿童哮喘患者的过敏原。应用F2600和303型肺功能仪分别测定不同年龄组哮喘儿童发作期的肺功能变化。结果：122例患者中过敏原测定96例呈阳性反应，阳性率78.7%，对屋尘过敏者81例，占84.4%，对尘螨过敏者63例，占65.6%，对多价昆虫过敏者49例，占51.0%。0～3岁组哮喘发作时75%潮气量与最高呼气流速之比(25/PF)值为(0.4637±0.0969)，潮气量与最高呼气流速之比(%V-PF)值为(0.1579±0.1000)，吸气时间与总呼吸时间之比(Ti/Tt)值为(0.3760±0.0377)，中期呼气流速与中期吸气流速之比(Me/Mi)值为(0.6437±0.1308)，与正常值比较均有显著差异，P<0.01。4～6岁组和7岁以上组哮喘发作期用力肺活量(FVC)、1秒钟用力呼气量(FEV1)、FEV1/FVC、最大呼气中期流量(PEF 25%～75%)与正常预计值比较有显著性差异，均P<0.01。结论：深圳地区儿童哮喘与外源性过敏原密切相关，肺功能仪测定儿童哮喘的肺功能变化有助于评估哮喘的发病情况。     

呼出气一氧化氮浓度测定在儿童支气管哮喘和咳嗽变异性哮喘中的诊断价值

目的 分析呼出气一氧化氮(FeNO)对于支气管哮喘和咳嗽变异性哮喘的诊断价值,并探讨能否应用FeNO区分支气管哮喘和咳嗽变异性哮喘。方法 选取2012年6月至2014年6月150例初诊为支气管哮喘的患儿以及120例初诊为咳嗽变异性哮喘的患儿为研究对象,对两组患儿进行FeNO检测、肺功能检查以及支气管激发试验;同期选取150例健康儿童为对照组,对对照组儿童行FeNO检测。采用受试者工作特征曲线(ROC)分析FeNO对于支气管哮喘和咳嗽变异性哮喘的诊断价值。结果 支气管哮喘和咳嗽变异性哮喘组患儿的FeNO值均高于对照组(P< 0.01),支气管哮喘组的FeNO值显著高于咳嗽变异性哮喘组(P< 0.01);支气管哮喘组FEV1/FVC%、FEV1%pred、PD20较咳嗽变异性哮喘组均降低(P< 0.01)。FeNO诊断支气管哮喘的最佳阈值为19.5 ppb,敏感度为83.3%,特异度为86.7%;FeNO诊断咳嗽变异性哮喘的最佳阈值为15.5 ppb,敏感度为67.5%,特异度为78.0%;FeNO区别支气管哮喘和咳嗽变异性哮喘的最佳阈值为28.5 ppb,敏感度为60.7%,特异度为82.5%。结论 FeNO测定可用于支气管哮喘和咳嗽变异性哮喘的诊断和鉴别诊断。     

肺炎支原体感染对哮喘儿童呼出气一氧化氮及肺功能影响的研究

目的 探讨肺炎支原体(Mycoplasma pneumoniae,MP)感染对哮喘患儿呼出气一氧化氮(fractional exhaled nitric oxide,FeNO)和肺功能水平的影响,分析呼出气一氧化氮与肺功能的相关性,为哮喘患儿的治疗和监测提供客观依据.方法 收集2011年6月至2013年1月在中国医科大学附属盛京医院小儿呼吸内科住院及门诊5~13岁急性轻、中度发作的哮喘患儿68例,于入组次日清晨检测MP-IgG抗体、MP-IgM抗体、或者MP-DNA、血清总IgE,同时进行FeNO和肺功能检查,根据病原学检查结果将患儿分为哮喘肺炎支原体感染组(哮喘MP感染组)36例,哮喘非肺炎支原体感染组(哮喘非MP感染组)32例,对比分析两组患儿FeNO和肺功能水平的差异,并进一步分析MP感染后FeNO和肺功能相关性.结果 哮喘MP感染组患儿FeNO值较哮喘非MP感染组明显升高,MP感染激素治疗组患儿FeNO水平比非MP感染激素治疗组升高,差异有统计学意义(P<0.05);两组患儿肺功能FVC、FEV1、FEV1/Vcmax、MEF25、MEF50之间比较差异无统计学意义(P>0.05),但MEF75、PEF比较有显著性差异(P<0.05);FeNO与肺功能(FVC、FEV1、FEV1/Vcmax、MEF50、MEF25、MEF75、PEF)之间比较无明显相关性(P>0.05).结论 哮喘儿童MP感染后FeNO值明显升高,MP感染后哮喘患儿FeNO水平与肺功能无显著相关性.     

呼出气一氧化氮在儿童哮喘中的临床价值

哮喘是一种气道慢性炎症性疾病,已成为儿童中最常见的慢性疾病之一.临床上对哮喘的诊断及治疗主要依据临床表现及肺功能,但两者并不能反映气道炎症.呼出气一氧化氮(exhaled nitric oxide,eNO)作为气道炎症的标志物,与气道炎症有显著相关性.eNO检测方法具有无创、简单、方便、特异性好等优点,在临床应用方面具有明显优势.该文介绍了NO在气道中的代谢及其作用,并从哮喘的诊断及鉴别诊断、哮喘管理方面阐述eNO检测在儿童哮喘临床应用中的研究进展.     

白三烯与一氧化氮在哮喘中关系的研究进展

一氧化氮(NO)是近年来研究较多的一种生物活性物质,在哮喘发病机制中具重要作用。而目前认为呼出气中NO(eNO)测定是反映哮喘气道炎症的新型无创伤性、极敏感的生物指标。eNO浓度在哮喘早期即增加,在哮喘恶化时进一步升高。白三烯是哮喘发病机制中又一重要的内源性炎性介质,与NO存在复杂的相互作用,而白三烯受体拮抗剂可降低哮喘患者的eNO浓度,其机制尚有待阐明。     

急性发作期哮喘患儿诱导痰中白细胞介素-5水平变化及其临床意义

目的　观察急性发作期哮喘患儿诱导痰中白细胞介素 5 (IL 5 )水平变化及其与哮喘发作期病情分度的关系 ,探讨其在哮喘发病机制中的作用和在临床诊治中的意义。方法　按随机分层设计 ,6 5例急性发作期哮喘患儿被分为轻、中、重度发作组 ,34例健康儿童作为对照组。采用超声雾化高渗盐水诱导痰液 ,以酶联免疫法(ELISA)测定诱导痰中IL 5水平 ,同时进行诱导痰中嗜酸细胞 (EOS)计数 ,测定用力呼气比值 (FEV1)。结果　哮喘急性发作期患儿诱导痰中EOS计数、IL 5水平均高于健康儿童组 ,FEV1则低于健康儿童组 ,差异均具有显著性(P <0 .0 1)。急性发作期哮喘患儿轻、中、重度各组间诱导痰中EOS逐渐增高 ,但差异无显著性 (P >0 .0 5 ) ;而IL 5水平随发作程度的加重而明显升高 ,轻、中、重度发作各组间两两比较差异均有显著性 (P <0 .0 5 ) ;重度哮喘患儿FEV1低于轻、中度哮喘 (P <0 .0 5 )。痰液中IL 5水平与EOS计数之间呈显著正相关 (r =0 .4 82 ,P <0 .0 5 ) ,与FEV1值之间呈显著负相关 (r =- 0 .6 4 7,P <0 .0 1)。结论　诱导痰中IL 5水平可能较EOS计数更能准确反映哮喘患儿气道炎症和哮喘发作时的病情程度 ,可以作为临床评价哮喘病情和药物疗效的准确灵敏的指标。     

Exhaled nitric oxide in childhood asthma

Endogenous synthesis of nitric oxide (NO) and its presence in exhaled air was observed in various species including humans. Particularly high levels were found in adults with bronchial asthma, possibly because of the underlying pulmonary inflammatory activity. We studied oral and nasal exhaled NO by chemiluminescence in 47 children aged between 6 and 10 years. Thirty children had bronchial asthma, 17 were healthy controls. In asthmatic children oral exhaled NO was 13.4±1.4 parts per billion (ppb) (mean±SEM), nasal exhaled NO was 21.7±1.5 ppb. In healthy controls oral exhaled NO was 7.2±1.0 ppb, nasal exhaled NO was 18.2±2.2 ppb. Oral exhaled NO was significantly higher in asthmatic children compared to healthy controls (P=0.0017). Nasal exhaled NO did not differ significantly in the two groups. There was a significant negative correlation between oral exhaled NO and forced expiratory volume in 1 s (FeV₁). No significant correlation between oral or nasal exhaled NO and other markers of obstructive lung function impairment, oral minute ventilation, the body mass index and the presence of upper respiratory tract infection could be found.     

Exhaled carbon monoxide in childhood asthma.

OBJECTIVES: Oxidative stress and inflammation induce the expression of heme oxygenase-1, which produces carbon monoxide (CO), and nitric oxide synthase, which produces nitric oxide (NO). Exhaled CO and NO levels are elevated in asthmatic patients and are decreased after corticosteroid treatment, suggesting that they may be useful as noninvasive markers of airway inflammation. STUDY DESIGN: We measured forced expiratory volume in the first second, PC(20), and exhaled CO and NO levels in 29 children (18 boys, mean age 11.5 +/- 0.53 years) with asthma of different severity and 40 nonsmoking children without asthma (21 boys, mean age 8.1 +/- 0.35 years). We also studied whether upper respiratory tract infections were associated with elevated exhaled CO. RESULTS: Exhaled CO levels (ppm) were significantly higher (2.17 +/- 0.21) in children with persistent asthma compared with those in children with infrequent episodic asthma (1.39 +/- 0.18, P <.05) and healthy children (1.01 +/- 0.12, P <.001). The CO levels in children with infrequent episodic asthma and the normal control group, however, were not different. In contrast, exhaled NO levels (ppb) were higher in children with persistent asthma (24.2 +/- 5.9, P <.001) and infrequent episodic asthma (14.5 +/- 3.73, P <.05) than in normal subjects (5.1 +/- 0.24), but no significant difference was seen between the 2 asthmatic groups. In healthy children with upper respiratory tract infections (n = 12), exhaled CO concentrations were significantly elevated (2.16 +/- 0.33) during the acute symptomatic phase. No correlation was found between exhaled CO and forced expiratory volume in the first second or PC(20). CONCLUSIONS: Noninvasive measurement of exhaled CO may provide complementary data for assessment of asthma control in children. However, elevated CO levels are nonspecific and may be found in association with an acute viral illness.     

Exhaled nitric oxide measurements in childhood asthma: comparison of two sampling techniques

Nitric oxide (NO) is being increasingly used to assess airway inflammation in childhood. The method recommended by the American Thoracic Society workshop is for a prolonged expiration against a resistance. However, this is very difficult to apply in young children. As a result there have been a number of studies in which mixed expired gas has been collected and analyzed for NO content as this requires very little cooperation. This method has, however, yet to be fully validated. The aims of this study were to compare the two sampling techniques of exhaled NO concentrations in asthmatic and healthy children and to assess the correlation between NO levels and spirometry values in asthmatic children We studied 25 control children, mean age 11.5 y, and 20 asthmatics, mean age 12 y. The exhaled NO was sampled using both the single breath technique (SB) and by measuring the NO content in mixed expired air after 1 min tidal breathing (ME). Forced expiratory volume in 1 s (FEV(1)) and expiratory flow rates at 25%, 50%, and 75% of vital capacity (FEF(25), FEF(50), FEF(75), respectively) were measured by compact II spirometer (best of three) in the 20 asthmatic children. The NO level was significantly higher in the asthmatics versus the control children when measured by SB (p = 0.0015) but not when measured by ME (p = 0.1913). The NO results measured by SB were significantly higher than ME results in the asthmatic children (p = 0.008). The NO levels were negatively correlated to FEV(1), FEF(25), FEF(50), and FEV(75) when measured by SB (p < 0.02) but not when measured by ME. The SB but not the ME method for measuring expired NO discriminates between asthmatic and control children and correlates well with the degree of airway obstruction. The use of the ME technique remains unproven.     

Exhaled nitric oxide in paediatric asthma and cystic fibrosis

Nitric oxide (NO) is present in exhaled air of humans. This NO is mostly produced in the upper airways, whereas basal NO excretion in the lower airways is low. Children with Kartagener's syndrome have an almost total lack of NO in nasally derived air, whereas adult asthmatics have increased NO in orally exhaled air. NO excretion was measured in the nasal cavity and in orally exhaled air in 19 healthy children, in 36 age matched subjects with asthma, and in eight children with cystic fibrosis. NO levels in orally exhaled air were similar in controls and in children with cystic fibrosis, at 4.8 (SD 1.2) v 5.8 (0.8) parts per billion (ppb), but were increased in asthmatic children who were untreated or were being treated only with low doses of inhaled steroids (13.8 (2.5) ppb). Nasal NO levels were reduced by about 70% in children with cystic fibrosis compared to controls and asthmatics. Measurements of airway NO release in different parts of the airways may be useful in non-invasive diagnosis and monitoring of inflammatory airway diseases.     

Spirometry‐adjusted fraction of exhaled nitric oxide increases accuracy for assessment of asthma control in children

Spirometry and exhaled nitric oxide are two important complimentary tools to identify and assess asthma control in children. We aimed to determine the ability of a new suggested spirometry‐adjusted fraction of exhaled nitric oxide (NO) index in doing that. A random sample of 1602 schoolchildren were screened by a health questionnaire, skin prick tests, spirometry with bronchodilation and exhaled NO. A total of 662 children were included with median (IQR) exhaled NO 11(14) ppb. Receiver operating characteristic (ROC) curves using exhaled NO equations from Malmberg, Kovesi and Buchvald, and spirometry‐adjusted fraction of exhaled NO values were applied to identify asthmatic children and uncontrolled asthma. Receiver operating characteristic (ROC) curves failed to identify asthmatic children (all AUC < 0.700). Spirometry‐adjusted fraction of exhaled NO/FEV₁ (AUC = 0.712; P = .010) and NO/FEF_25%‐75% (AUC = 0.735 P = .004) had a fair and increased ability to identify uncontrolled disease compared with exhaled NO (AUC = 0.707; P = .011) or the Malmberg equation (AUC = 0.701; P = .014). Sensitivity and specificity identifying non‐controlled asthma were 59% and 81%, respectively, for the cut‐off value of 9.7 ppb/L for exhaled NO/FEV₁, and 40% and 100% for 15.7 ppb/L/s for exhaled NO/FEF_25%‐75%. Exhaled NO did not allow to identify childhood asthma. Spirometry‐adjusted fraction of exhaled NO performed better‐assessing asthma control in children. Thus, although more validation studies are needed, we suggest its use in epidemiological studies to assess asthma control.     

CMV和HCV肝炎婴儿血清IFN-α,IL-8,TNF-α和NO的水平变化

目的　了解巨细胞病毒肝炎 (CMV IgM抗体阳性 )和丙型肝炎 (HCV IgM抗体阳性 ) 1～ 6月的婴儿患者血清中某些炎性介质的异常变化。方法　应用ELISA法和硝酸还原酶法 ,分别检测了 5 6例CMV抗体和6 7例HCV抗体阳性婴儿肝炎综合征 (婴肝 )患儿及正常对照组 5 8例小儿的血清干扰素α (IFN α) ,白细胞介素 8(IL 8) ,肿瘤坏死因子 α (TNF α)和一氧化氮 (NO)的含量。结果　正常对照组 5 8例血清IFN α ,IL 8,TNF α ,NO含量分别为 2 2 6 .74± 73.82ng/L ,13.2 4± 5 .36ng/L ,2 17.14± 76 .30ng/L ,2 5 .98± 8.70 μmol/L。CMV抗体阳性婴肝组血清IFN α ,IL 8,TNF α和NO的含量分别为 5 82 .2 6± 131.72ng/L ,75 .2 8± 33.5 7ng/L ,42 9.46± 15 6 .32ng/L和5 9.87± 16 .42 μmol/L ,明显高于正常对照组 (P <0 .0 1) ;HCV抗体阳性婴肝组上述四项指标含量分别为5 5 8.32± 114.6 4ng/L ,71.34± 2 7.6 4ng/L ,374.35± 138.4ng/L和 6 2 .2 4± 2 1.38μmol/L ,其含量亦明显高于正常对照组 (P <0 .0 0 1)。CMV与HCV抗体阳性婴肝组比较 ,无明显差异 (P >0 .0 5 )。TNF α和NO在这两组婴肝中分别呈正相关 (r1=0 .6 2 ,r2 =0 .5 7,P<0 .0 1)。结论　CMV和HCV抗体阳性婴肝急性期患儿 ,血清TNF α,IL 8,IFN     

普米克气雾剂治疗儿童哮喘疗效观察

目的　观察普米克气雾剂治疗儿童哮喘前后的最高呼气峰流速值 (PEF)及血清嗜酸细胞阳离子蛋白 (ECP)的变化。方法　对 113例儿童哮喘病人 ,使用普米克气雾剂 [(2 0 0～ 80 0 ) μg/d],3月～ 1年。采用峰流速仪监测PEF ,并用荧光免疫法 ,使用PharmaciaCAP系统 (瑞典 )测定部分病儿治疗前后的血清ECP。结果　使用普米克治疗后 ,PEF明显增高 ,3个月、6个月、1年的PEF占预计值的百分比 (PEF % )分别为 (93.6± 5 .4) ,(93.0± 4.2 ) ,(94.5± 4.5 ) ,与治疗前 (70 .4± 19.1)比较 ,差异有显著性 ,P <0 .0 1。治疗后ECP为 (7.5± 2 .7)μg/L ,比治疗前 (2 4.0± 17.1) μg/L明显下降 ,P <0 .0 1,差异有显著性。结论　普米克气雾剂治疗儿童哮喘副作用小、安全有效、方法简便 ,用于儿童哮喘的中、长期防治 ,值得推广。     

Nitric oxide airway diffusing capacity and mucosal concentration in asthmatic schoolchildren

Asthmatic patients show increased concentrations of nitric oxide (NO) in exhaled air (Feno). The diffusing capacity of NO in the airways (Dawno), the NO concentrations in the alveoli and the airway wall, and the maximal airway NO diffusion rate have previously been estimated noninvasively by measuring Feno at different exhalation flow rates in adults. We investigated these variables in 15 asthmatic schoolchildren (8-18 y) and 15 age-matched control subjects, with focus on their relation to exhaled NO at the recommended exhalation flow rate of 0.05 L/s (Feno0.05), age, and volume of the respiratory anatomic dead space. NO was measured on-line by chemiluminescence according to the European Respiratory Society's guidelines, and the NO plateau values at three different exhalation flow rates (11, 99, and 382 mL/s) were incorporated in a two-compartment model for NO diffusion. The NO concentration in the airway wall (p < 0.001), Dawno (p < 0.01), and the maximal airway NO diffusion rate (p < 0.001) were all higher in the asthmatic children than in control children. In contrast, there was no difference in the NO concentration in the alveoli (p = 0.13) between the groups. A positive correlation was seen between the volume of the respiratory anatomic dead space and Feno0.05 (r = 0.68, p < 0.01), the maximal airway NO diffusion rate (r = 0.71, p < 0.01), and Dawno (r = 0.56, p < 0.01) in control children, but not in asthmatic children. Feno0.05 correlated better with Dawno in asthmatic children (r = 0.65, p < 0.01) and with the NO concentration in the airway wall in control subjects (r < 0.77, p < 0.001) than vice versa. We conclude that Feno0.05 increases with increasing volume of the respiratory anatomic dead space in healthy children, suggesting that normal values for Feno0.05 should be related to age or body weight in this age group. Furthermore, the elevated Feno0.05 seen in asthmatic children is related to an increase in both Dawno and NO concentration in the airway wall. Because Dawno correlates with the volume of the respiratory anatomic dead space in control subjects and Feno0.05 correlates with Dawno in asthmatic children, we suggest that Dawno partly reflects the total NO-producing surface area and that a larger part of the bronchial tree produces NO in asthmatic children than in control children.