呼出气的电子鼻分析用于诊断呼吸机相关性肺炎。

Electronic nose analysis of exhaled breath to diagnose ventilator-associated pneumonia.

作者信息

Schnabel R M, Boumans M L L, Smolinska A, Stobberingh E E, Kaufmann R, Roekaerts P M H J, Bergmans D C J J

机构信息

Departments of Intensive Care Medicine, Maastricht University Medical Centre, The Netherlands.

Medical Microbiology, Maastricht University Medical Centre, The Netherlands.

出版信息

Respir Med. 2015 Nov;109(11):1454-9. doi: 10.1016/j.rmed.2015.09.014. Epub 2015 Sep 30.

DOI:10.1016/j.rmed.2015.09.014

PMID:26440675

Abstract

BACKGROUND

Exhaled breath analysis is an emerging technology in respiratory disease and infection. Electronic nose devices (e-nose) are small and portable with a potential for point of care application. Ventilator-associated pneumonia (VAP) is a common nosocomial infection occurring in the intensive care unit (ICU). The current best diagnostic approach is based on clinical criteria combined with bronchoalveolar lavage (BAL) and subsequent bacterial culture analysis. BAL is invasive, laborious and time consuming. Exhaled breath analysis by e-nose is non-invasive, easy to perform and could reduce diagnostic time. Aim of this study was to explore whether an e-nose can be used as a non-invasive in vivo diagnostic tool for VAP.

METHODS

Seventy-two patients met the clinical diagnostic criteria of VAP and underwent BAL. In thirty-three patients BAL analysis confirmed the diagnosis of VAP [BAL+(VAP+)], in thirty-nine patients the diagnosis was rejected [BAL-]. Before BAL was performed, exhaled breath was sampled from the expiratory limb of the ventilator into sterile Tedlar bags and subsequently analysed by an e-nose with metal oxide sensors (DiagNose, C-it, Zutphen, The Netherlands). From further fifty-three patients without clinical suspicion of VAP or signs of respiratory disease exhaled breath was collected to serve as a control group [control(VAP-]). The e-nose data from exhaled breath were analysed using logistic regression.

RESULTS

The ROC curve comparing [BAL+(VAP+)] and [control(VAP-)] patients had an area under the curve (AUC) of 0.82 (95% CI 0.73-0.9). The sensitivity was 88% with a specificity of 66%. The comparison of [BAL+(VAP+)] and [BAL-] patients revealed an AUC of 0.69; 95% CI 0.57-0.81) with a sensitivity of 76% with a specificity of 56%.

CONCLUSION

E-nose lacked sensitivity and specificity in the diagnosis of VAP in the present study for current clinical application. Further investigation into this field is warranted to explore the diagnostic possibilities of this promising new technique.

摘要

背景

呼出气分析是呼吸系统疾病和感染领域的一项新兴技术。电子鼻设备体积小且便于携带，具有床旁应用的潜力。呼吸机相关性肺炎（VAP）是重症监护病房（ICU）常见的医院感染。目前最佳的诊断方法是基于临床标准，结合支气管肺泡灌洗（BAL）及后续的细菌培养分析。BAL具有侵入性、操作繁琐且耗时。电子鼻进行呼出气分析是非侵入性的，易于操作且可缩短诊断时间。本研究的目的是探讨电子鼻能否作为VAP的非侵入性体内诊断工具。

方法

72例符合VAP临床诊断标准的患者接受了BAL。33例患者的BAL分析确诊为VAP[BAL+(VAP+)]，39例患者的诊断被排除[BAL-]。在进行BAL之前，从呼吸机呼气端采集呼出气样本至无菌泰德拉袋中，随后用带有金属氧化物传感器的电子鼻（DiagNose，C-it，荷兰聚特芬）进行分析。另外从53例无VAP临床怀疑或呼吸系统疾病体征的患者中采集呼出气作为对照组[对照组(VAP-)]。使用逻辑回归分析呼出气的电子鼻数据。

结果

比较[BAL+(VAP+)]组和[对照组(VAP-)]组患者的ROC曲线下面积（AUC）为0.82（95%CI 0.73 - 0.9）。灵敏度为88%，特异性为66%。比较[BAL+(VAP+)]组和[BAL-]组患者的AUC为0.69；95%CI 0.57 - 0.81），灵敏度为76%，特异性为56%。