支气管激发试验与小气道功能的改变

Bronchial prevocational test and change of small airway function

目的 探讨支气管气道高反应性测定中小气道功能的变化情况。方法 以组织胺为激发源 ,经定量雾化吸入器吸入 ,对 6 6例慢性咳嗽患者进行非特异性激发试验 ,同时观察试验前后FEV1,MEF50 及R0 的变化情况 ,并进行分析。结果 在 6 6例患者中 ,FEV1下降超过 2 0 %的阳性率为 5 0 % ,MEF50 下降超过 2 0 %的阳性率为 71% ,MEF50 与FEV1下降比例有明显相关性 ,MEF50 下降百分比 (MEF50 % )与试验前后R0 的差值 (R0 -d)亦有相关性 ,但是FEV1下降百分比 (FEV1% )与R0 -d无明显相关性。同时 ,激发阳性患者的MEF50 与R0 在试验前即与阴性组患者有明显差异性 ,而两组的基础FEV1,R4及R16无差异。另外 ,两组患者激发前后R4的差值 (R4-d)有差异性 ,而R16-d无显著差异。结论 在可疑哮喘患者的常规肺功能检查中 ,MEF50 及R0 比FEV1更敏感 ,更能提示早期小气道的病变。同时在激发试验中 ,应结合小气道功能指标进行结果判定 ,以提高试验的敏感性及特异性。

Objective It is to investigate the change of small airway function in bronchial provocation test. Methods 66 patients with chronic cough were selected for non specific bronchial provocation test. As the provocation substance, histamine was administrated through flow controlled (fixed quantity) nebulizer system. The change of FEV 1, MEF 50 and R 0 were observed. Results FEV 1 of 50% patients decreased more than 20 %, while 71% patients' MEF 50 decreased more than 20%, and the descent ratio of FEV 1 and MEF 50 was significantly correlated. The change of R 0 was related to the percentage FEF decreased, but not related to FEV 1. Before test, MEF 50 and R 0 were significantly different between the positive patients and negative patients. Conclusion When routine lung function examination is performed in suspected asthma patients, the indices of small airway function such as MEF 50 and R 0 are more sensitive than FEV 1. So in order to increase sensitive of BPT, small airway functional indices should be considered besides FEV 1 and PEF.