Leicester NIHR Biomedical Research Centre (Respiratory Theme), Glenfield Hospital, Leicester, UK.
Department of Respiratory Sciences, College of Life Sciences, University of Leicester, Leicester, UK.
BMJ Paediatr Open. 2021 Sep 8;5(1):e001003. doi: 10.1136/bmjpo-2020-001003. eCollection 2021.
Investigating airway inflammation and pathology in wheezy preschool children is both technically and ethically challenging. Identifying and validating non-invasive tests would be a huge clinical advance. Real-time analysis of exhaled volatile organic compounds (VOCs) in adults is established, however, the feasibility of this non-invasive method in young children remains undetermined.
To determine the feasibility and acceptability of obtaining breath samples from preschool children by means of real-time mass spectrometry analysis of exhaled VOCs.
Breath samples from preschool children were collected and analysed in real time by proton transfer reaction-time of flight-mass spectrometry (PTR-TOF-MS) capturing unique breath profiles. Acetone (mass channel m/z 59) was used as a reference profile to investigate the breath cycle in more detail. Dynamic time warping (DTW) was used to compare VOC profiles from adult breath to those we obtained in preschool children.
16 children were recruited in the study, of which eight had acute doctor-diagnosed wheeze (mean (range) age 3.2 (1.9-4.5) years) and eight had no history of wheezing (age 3.3 (2.2-4.1) years). Fully analysable samples were obtained in 11 (68%). DTW was used to ascertain the distance between the time series of mass channel m/z 59 (acetone) and the other 193 channels. Commonality of 12 channels (15, 31, 33, 41, 43, 51, 53, 55, 57, 60, 63 and 77) was established between adult and preschool child samples despite differences in the breathing patterns.
Real-time measurement of exhaled VOCs by means of PTR-MS is feasible and acceptable in preschool children. Commonality in VOC profiles was found between adult and preschool children.
研究喘鸣学龄前儿童的气道炎症和病理学在技术和伦理上都具有挑战性。识别和验证非侵入性测试将是一个巨大的临床进步。实时分析成年人呼出的挥发性有机化合物（VOC）已经建立，然而，这种非侵入性方法在幼儿中的可行性仍未确定。
确定通过实时质子转移反应-飞行时间质谱分析（PTR-TOF-MS）分析呼出 VOC 来从学龄前儿童中获取呼吸样本的可行性和可接受性。
通过 PTR-TOF-MS 实时采集和分析学龄前儿童的呼吸样本，捕获独特的呼吸谱。使用丙酮（质量通道 m/z 59）作为参考谱，更详细地研究呼吸周期。动态时间规整（DTW）用于比较成人呼吸和我们在学龄前儿童中获得的 VOC 谱。
研究共招募了 16 名儿童，其中 8 名患有急性医生诊断的喘鸣（平均（范围）年龄 3.2（1.9-4.5）岁），8 名无喘鸣史（年龄 3.3（2.2-4.1）岁）。获得了 11 个（68%）可完全分析的样本。DTW 用于确定质量通道 m/z 59（丙酮）和其他 193 个通道的时间序列之间的距离。尽管呼吸模式存在差异，但在成人和学龄前儿童样本之间建立了 12 个通道（15、31、33、41、43、51、53、55、57、60、63 和 77）的共性。
通过 PTR-MS 实时测量呼出 VOC 在学龄前儿童中是可行且可接受的。在成人和学龄前儿童之间发现了 VOC 谱的共性。
