Marotta Alex, Klinnert Mary D, Price Marcella R, Larsen Gary L, Liu Andrew H
Division of Pediatric Allergy and Immunology, National Jewish Medical and Research Center, and the Department of Pediatrics, University of Colorado Health Sciences Center, Denver, 80206, USA.
J Allergy Clin Immunol. 2003 Aug;112(2):317-22. doi: 10.1067/mai.2003.1627.
Objective lung function measurements are routinely used to diagnose and manage asthma, but their utility for young children has not been defined.
Bronchodilator responses were measured by means of impulse oscillometry (IOS) and compared with conventional spirometry to determine the value of lung function measures in 4-year-old asthma-prone children.
The study participants were in the Childhood Asthma Prevention Study (National Institute of Health/National Institute of Allergy and Infectious Diseases) and at risk for asthma. At age 4 years, concurrent asthma was determined by using a previously validated modified American Thoracic Society questionnaire. Children performed IOS and spirometry before and after albuterol administration and underwent skin prick testing to 13 common allergens to assess atopy. IOS measures were as follows: airways resistance at 5 Hz and 10 Hz, airways reactance at 5 Hz and 10 Hz, and resonant frequency.
Asthmatic patients versus nonasthmatic patients significantly differed in their IOS-assessed bronchodilator responses through Delta resistance at 5 Hz (medians, 27% vs 17%; P =.02) and Delta resistance at 10 Hz (24% vs 16%; P =.03). Because atopic children who have frequent wheezing are at risk for persistent asthma, the data were analyzed in regard to atopic patients with or without asthma. IOS strongly distinguished atopic asthmatic children through Delta resistance at 5 Hz (36% vs 13%, P =.007), Delta resistance at 10 Hz (25% vs 11%, P =.02), and Delta reactance at 10 Hz (47% vs 12%, P =.03). Conventional spirometry did not establish similar statistically significant findings.
IOS bronchodilator responses are remarkably abnormal in 4-year-old children, who are most likely to have persistent asthma. IOS is a useful diagnostic tool in early asthma development and might be a helpful objective outcome measure of early interventions.
客观肺功能测量常用于哮喘的诊断和管理，但对幼儿的效用尚未明确。
通过脉冲振荡法（IOS）测量支气管扩张剂反应，并与传统肺量计进行比较，以确定4岁易患哮喘儿童肺功能测量的价值。
研究参与者来自儿童哮喘预防研究（美国国立卫生研究院/国立过敏与传染病研究所），有哮喘风险。4岁时，使用先前验证的改良美国胸科学会问卷确定并发哮喘情况。儿童在使用沙丁胺醇前后进行IOS和肺量计检查，并接受针对13种常见过敏原的皮肤点刺试验以评估特应性。IOS测量指标如下：5Hz和10Hz时的气道阻力、5Hz和10Hz时的气道电抗以及共振频率。
哮喘患者与非哮喘患者在IOS评估的支气管扩张剂反应方面存在显著差异，5Hz时的Δ阻力（中位数分别为27%对17%；P = 0.02）和10Hz时的Δ阻力（24%对16%；P = 0.03）。由于频繁喘息的特应性儿童有患持续性哮喘的风险，因此对有或无哮喘的特应性患者的数据进行了分析。IOS通过5Hz时的Δ阻力（36%对13%，P = 0.007）、10Hz时的Δ阻力（25%对11%，P = 0.02）和10Hz时的Δ电抗（47%对12%，P = 0.03）有力地区分了特应性哮喘儿童。传统肺量计未得出类似的统计学显著结果。
IOS支气管扩张剂反应在4岁儿童中异常明显，这些儿童最有可能患持续性哮喘。IOS是早期哮喘发展中有用的诊断工具，可能是早期干预的有益客观结果指标。
