哮喘联盟

   摘要
   背景：呼吸专业领域建议在成人及儿童中使用标准的方法测定FeNO，然而在学龄前儿童中的可行性仍是个问题。获得稳态FeNO所需要的呼气时间尚不清楚。本文主要旨在研究一种采用年龄校正的呼气次数的改良单次呼吸FeNO测定方法的可行性。本文同时研究到达NO稳态水平的时间和高度之间的关系，以及FeNO与哮喘及当前吸入性糖皮质激素（ICS）治疗的关系。
   方法：63例年龄3～10岁的儿童使用含有新开发的气流控制单元的手持式电化学装置接受FeNO测定。呼气次数预先与年龄相适应。运用化学发光分析仪即时取样呼出气体，以测定达到稳态NO水平的时间。
   结果：81%的受试儿童至少有一次被认可的测定结果。4岁以上成功率高（96%）.3～4岁儿童达到稳态[NO]时间（均数和四分位区间）为2.5（2.4-3.5）秒，5～6岁儿童为3.5（2.7-3.8）秒.高度与达到稳态时间有关（r2=0.13, p=0.02）。未使用ICS的哮喘儿童（n=19）FeNO（几何均数（95%CI）15.9 ppb (12.2-20.9高于健康对照组 (n=8) 9.1 ppb (6.6-12.4) 及哮喘治疗组(n=24) 11.5 ppb (9.7-13.6)。
   结论：研究发现该运用年龄校正呼气次数的改良单次呼吸测定方法在年龄4～10岁的儿童中可行性很高。未使用ICS的哮喘儿童FeNO水平低于当前指南的截断值（20 ppb），突出了在设定参考值纳入年龄因素的重要性。本文受版权保护。保留所有权利。
 

（杨冬 审校）
Pediatr Allergy Immunol. 2015 Jul 16.doi: 10.1111/pai.12447. [Epub ahead of print]

 

New method for single-breath FeNO measurement with improved feasibility in preschool children with asthma.
 

Heijkenskjöld-Rentzhog C1, Kalm-Stephens P1, Nordvall L1, Malinovschi A2, Alving K1.
 

Abstract
BACKGROUND:Respiratory societies recommend use of standardized methodologies for FeNO measurements in adults and children, but in pre-schoolers, feasibility remains a problem. The exhalation time needed to obtain steady-state FeNO is unclear. Our primary aim was to study the feasibility of an adapted single-breath FeNO method with age-adjusted exhalation times. We also studied the association between time to steady-state NO level and height, as well as FeNO in relation to asthma and current treatment with inhaled corticosteroids (ICS).
METHODS:Sixty-three children aged 3-10 years performed FeNO measurements with a hand-held electrochemical device with a newly developed flow-control unit. Exhalation times were pre-adapted to age. Exhaled air was simultaneously sampled to a chemiluminescence analyser to measure time to steady-state NO level.
RESULTS:Eighty-one percent of the children achieved at least one approved measurement. From 4 years upwards, success rate was high (96%). Time to steady-state [NO] (median and interquartile range) was 2.5 s (2.4-3.5) at age 3-4 years and 3.5 s (2.7-3.8) at 5-6 years. Height was associated with time to steady-state (r2=0.13, p=0.02). FeNO (geometric mean (95% CI)) was higher in ICS-naïve asthmatic children (n=19): 15.9 ppb (12.2-20.9), than in both healthy controls (n=8) 9.1 ppb (6.6-12.4) and asthmatic subjects on treatment (n=24) 11.5 ppb (9.7-13.6).
CONCLUSION:We found this adapted single-breath method with age-adjusted exhalation times highly feasible for children aged 4-10 years. ICS-naïve asthmatic children had FeNO levels under the current guideline cut-off level (20 ppb), highlighting the importance of taking age into account when setting reference values. This article is protected by copyright. All rights reserved.
 

Pediatr Allergy Immunol. 2015 Jul 16.doi: 10.1111/pai.12447. [Epub ahead of print]