呼出气分析在预测和(或)早期诊断急性呼吸窘迫综合征中的研究进展

Prediction and early diagnosis of acute respiratory distress syndrome by exhaled breath analysis

急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)是多种危重疾病的并发症,其病理特征为急性起病、大量蛋白聚集、弥漫性肺水肿。目前,采取避免机械通气所致肺损伤的无创通气方式是治疗的首选策略。提前预测或早期识别是预防ARDS发生的关键,可大大降低发病率和病死率。呼出气中含有多种挥发性有机物(volatile organic compounds,VOCs),包含数百种和生理病理相关的小分子物质。在一些研究中,通过色谱和质谱(gas-chromatography and mass-spectrometry,GS-MS)分析呼出气可以对ARDS进行预测和早期诊断。许多呼出气标志物与脂质过氧化反应有关。辛烷在ARDS期间含量增加,已被确定为ARDS的典型标志物。目前,没有一种可行的呼出气检测方法可直接应用于临床,因为在允许呼出气检测技术应用于ICU前必须要完成两个关键步骤。首先,任何呼出气标志物必须在体外多个研究中心得到确认,且呼出气测试结果应超过临床预测评分;其次,呼出气测试技术应在ICU内分散实验室进行,检测时间应尽量缩短,且需经过培训的护士操作。大多数呼出气标志物与脂质过氧化反应有关,辛烷作为ARDS的典型标志物在体外群组研究中得以证实。通过不断的实验研究及探索,呼出气分析技术应用于ARDS的预测和早期诊断未来可望实现。

The acute respiratory distress syndrome (ARDS) is a complication of critical illness that is characterized by acute onset, protein rich, pulmonary edema.There is no treatment for ARDS, other than the reduction of additional ventilator induced lung injury. Prediction or early recognition is the key to prevent the occurrence of ARDS and it can reduce the rate of mortality and morbidity.Exhaled breath contains volatile organic compounds (VOCs),it contains hundreds of small molecules linked to several physiological and pathophysiological processes.Analysis of exhaled breath through gas-chromatography and mass-spectrometry (GC-MS) has resulted in an accurate diagnosis of ARDS in several studies .Most identified markers are linked to lipid peroxidation.Octane is one of the few markers that was validated as a marker of ARDS and is pathophysiologically likely to be increased in ARDS.None of the currently studied breath analysis methods is directly applicable in clinical practice.Two steps have to be taken before any breath test can be allowed into the intensive care unit.First,external validation in a multi-center study is a prerequisite for any of the candidate breath markers and the breath test should outperform clinical prediction scores.Second,the technology for breath analysis should be adapted so that it is available at a decentralized lab inside the intensive care unit and can be operated by trained nurses,in order to reduce the analysis time.In conclusion,exhaled analysis might be used for the early diagnosis and prediction of ARDS in the near future but several obstacles have to be taken in the coming years.Most of the candidate markers can be linked to lipid peroxidation.Through constant exprimental research and exploration,the application of exhalation analysis technolosy to the prediction and early diagnosis of ARDS will soon be realized.