Lázár Zsófia, Horváth Péter, Puskás Rita, Gálffy Gabriella, Losonczy György, Horváth Ildikó, Bikov András
a Department of Pulmonology , Semmelweis University , 1/c Diós árok.
b National Korányi Institute of Pulmonology , 1 Pihenő Street , Budapest , Hungary.
J Asthma. 2019 Jun;56(6):584-593. doi: 10.1080/02770903.2018.1477957. Epub 2018 Oct 30.
Extended nitric oxide (NO) analysis offers the partitioned monitoring of inflammation in central and peripheral airways. Different mathematical models are used to estimate pulmonary NO dynamics in asthma with variable results and limitations. We aimed to establish a protocol for extended NO analysis in patients with differing asthma severity.
Forty patients with stable asthma and 25 matched control subjects were recruited. Exhaled NO was measured at constant flow rates between 10 and 300 mL/s. Twelve controls performed NO measurements weekly for 4 weeks.
The proportions of patients with technically acceptable measurements at 10-30-50-100-150-200-250-300 mL/s exhalation flow rates were 8-58-100-98-98-95-90-80%, respectively. Alveolar NO (CANO) and total flux of NO in the conducting airways (JawNO) were calculated with the linear method from NO values measured at 100-150-200-250 mL/s exhalation flows. The mean intrasubject bias for JawNO and CANO in controls was 0.16 nL/s and 0.85 ppb, respectively. Both JawNO (1.31/0.83-2.97/vs. 0.70/0.54-0.87/nL/s, p < 0.001) and CANO (4.08/2.63-7.16/vs. 2.42/1.83-2.89/ppb, p < 0.001) were increased in patients with asthma compared to controls. In patients, CANO correlated with RV/TLC (r = 0.58, p < 0.001), FEF (p = 0.02, r = -0.36) and DL,CO (r = -0.46, p = 0.004). JawNO was not related to lung function parameters.
Calculation of alveolar NO concentration with the linear method from values obtained at medium flow rates (100-250 mL/s) is feasible even in asthmatic patients with severe airflow limitation and may provide information on small airways dysfunction in asthma.
扩展一氧化氮（NO）分析可对中央气道和外周气道的炎症进行分区监测。不同的数学模型用于估计哮喘患者的肺一氧化氮动力学，结果各异且存在局限性。我们旨在建立一套针对不同哮喘严重程度患者的扩展NO分析方案。
招募了40例稳定期哮喘患者和25名匹配的对照受试者。在10至300毫升/秒的恒定流速下测量呼出的NO。12名对照受试者每周进行4周的NO测量。
在呼气流量为10 - 30 - 50 - 100 - 150 - 200 - 250 - 300毫升/秒时，测量技术上可接受的患者比例分别为8% - 58% - 100% - 98% - 98% - 95% - 90% - 80%。采用线性方法根据在100 - 150 - 200 - 250毫升/秒呼气流量下测得的NO值计算肺泡NO（CANO）和传导气道中NO的总通量（JawNO）。对照受试者中JawNO和CANO的平均受试者内偏差分别为0.16纳升/秒和0.85 ppb。与对照相比，哮喘患者的JawNO（1.31/0.83 - 2.97/对比0.70/0.54 - 0.87/纳升/秒，p < 0.001）和CANO（4.08/2.63 - 7.16/对比2.42/1.83 - 2.89/ppb，p < 0.001）均升高。在患者中，CANO与残气量/肺总量（RV/TLC）相关（r = 0.58，p < 0.001），与用力呼气流量（FEF）相关（p = 0.02，r = -0.36），与一氧化碳弥散量（DL,CO）相关（r = -0.46，p = 0.004）。JawNO与肺功能参数无关。
即使在气流严重受限的哮喘患者中，采用线性方法根据中等流速（100 - 250毫升/秒）下获得的值计算肺泡NO浓度也是可行的，并且可能为哮喘患者小气道功能障碍提供信息。
