University of Otago, Christchurch, New Zealand.
J Breath Res. 2009 Mar;3(1):016001. doi: 10.1088/1752-7155/3/1/016001. Epub 2009 Jan 8.
The measurement of volatile organic compounds in exhaled breath is becoming recognized as a method of disease diagnosis and therapeutic monitoring. The aim of this study was to validate the collection of breath from intubated patients in the intensive care setting. This was done by assembling a system of ventilators and humidification to emulate the human respiratory system. A known concentration of acetone was spiked into the system to simulate alveolar and dead-space 'breath'. Selected-ion flow tube mass spectrometry (SIFT-MS) was used to directly measure gas at two separate points (headspace, distal circuit end) and from Tedlar bags collected using a remote breath fractionator. The mean acetone concentration for headspace, distal circuit end and Tedlar bag concentrations were calculated. The fractionator was effective in separating the early (dead space) and late phases of exhaled breath. Results from the late Tedlar bag samples collected by the remote breath fractionator showed a clear correlation with headspace and distal circuit end acetone concentrations. The collection for remote analysis of breath samples from immobile patients is made possible using the breath fractionator in conjunction with SIFT-MS analysis.
呼气中挥发性有机化合物的测量正逐渐被认为是一种疾病诊断和治疗监测的方法。本研究的目的是验证在重症监护环境下对插管患者采集呼气的方法。这是通过组装一个呼吸机和加湿系统来模拟人体呼吸系统来实现的。将已知浓度的丙酮注入系统中，以模拟肺泡和死腔“呼气”。使用选择离子流管质谱（SIFT-MS）直接测量两个不同点（顶部空间、远端回路末端）和使用远程呼气分离器收集的特德纶袋中的气体。计算了顶部空间、远端回路末端和特德纶袋浓度的丙酮平均浓度。分离器有效地分离了呼气的早期（死腔）和晚期阶段。使用远程呼吸分离器收集的晚期特德纶袋样本的结果与顶部空间和远端回路末端丙酮浓度显示出明显的相关性。使用呼吸分离器结合 SIFT-MS 分析，可对不能移动的患者进行远程呼气样本采集。
