Department of Anesthesia and Intensive Care, Copenhagen University Hospital-North Zealand, Hilleroed, Denmark.
Department of Clinical Microbiology, Copenhagen University Hospital-Rigshospitalet, Copenhagen, Denmark.
J Breath Res. 2023 Sep 25;17(4). doi: 10.1088/1752-7163/acf607.
It can be a clinical challenge to distinguish inflammation from infection in critically ill patients. Therefore, valid and conclusive surrogate markers for infections are desired. Nitric oxide (NO) might be that marker since concentrations of exhaled NO have shown to change in the presence of various diseases. This observational, prospective, single-center feasibility study aimed to investigate if fractional exhaled NO (FeNO) can be measured in intubated patients with or without infection, pneumonia and septic shock in a standardized, reliable setting. 20 intubated patients in the intensive care unit (ICU) were included for analysis. FeNO mean values were measured in the endotracheal tube via the suction channel using a chemiluminescence based analyzer. We developed a pragmatic method to measure FeNO repeatedly and reliably in intubated patients using a chemiluminescence based analyzer. We found a median of 0.98 (0.59-1.44) FeNO mean (ppb) in exhaled breath from all 20 intubated patient. Intubated patient with suspected infection had a significantly lower median FeNO mean compared with the intubated patients without suspected infection. Similarly did patients with septic shock demonstrate a significantly lower median FeNO mean than without septic shock. We found no statistical difference in median FeNO mean for intubated patients with pneumonia. It was feasible to measure FeNO in intubated patients in the ICU. Our results indicate decreased levels of FeNO in infected intubated patients in the ICU. The study was not powered to provide firm conclusions, so larger trials are needed to confirm the results and to prove FeNO as a useful biomarker for distinguishment between infection and inflammation in the ICU.
在危重病患者中区分炎症和感染可能具有临床挑战性。因此，需要有效的、明确的感染替代标志物。一氧化氮（NO）可能就是这样的标志物，因为呼气中 NO 的浓度已被证明在存在各种疾病时会发生变化。这项观察性、前瞻性、单中心可行性研究旨在调查在标准化、可靠的环境中，是否可以在有或没有感染、肺炎和感染性休克的气管插管患者中测量呼出气中 NO 分数（FeNO）。共纳入 20 名 ICU 中的气管插管患者进行分析。使用基于化学发光的分析仪通过抽吸通道在气管内导管中测量 FeNO 平均值。我们开发了一种实用的方法，使用基于化学发光的分析仪在气管插管患者中反复、可靠地测量 FeNO。我们发现所有 20 名气管插管患者的呼气中 FeNO 平均值中位数为 0.98（0.59-1.44）（ppb）。与无疑似感染的气管插管患者相比，疑似感染的气管插管患者的 FeNO 平均值中位数显著降低。同样，患有感染性休克的患者的 FeNO 平均值中位数也显著低于无感染性休克的患者。我们发现肺炎气管插管患者的 FeNO 平均值中位数无统计学差异。在 ICU 中测量气管插管患者的 FeNO 是可行的。我们的结果表明，ICU 中感染的气管插管患者的 FeNO 水平降低。该研究没有足够的能力提供确凿的结论，因此需要更大的试验来证实这些结果，并证明 FeNO 作为区分 ICU 中感染和炎症的有用生物标志物的作用。
