Valletta E A, Piacentini G L, Del Col G, Boner A L
Paediatric Clinic, University of Verona, Italy.
J Asthma. 1997;34(2):127-31. doi: 10.3109/02770909709075657.
Sensitivity of forced expiratory flow between 25% and 75% of the vital capacity (FEF25-75) in detecting airway obstruction was investigated in 14 children with mild-moderate asthma, allergic to house dust mites, while at high altitude (1756 m). Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), FEF25-75, and peak expiratory flow (PEF) were measured every 2 weeks for 12 weeks (total, 84 measurements). The presence or absence of wheezing at the chest auscultation was ascertained before each test. During the study period, a significant improvement of both mean (SD) FEF25-75 [61 (12)% vs. 68 (11)% of the predicted value, p = 0.005] and PEF [95 (16)% vs. 103 (13)%, p = 0.002] was observed. FEV1 changed only marginally [82 (7)% vs. 86 (6)%, p = 0.05]. Wheezing was present on 12/84 occasions. Wheezing was associated with abnormal FEF25-75 values on most occasions but not with abnormal FEV1 or PEF. FEF25-75 was decreased on 51% of days in which wheezing was absent. FEV1 and PEF were, respectively, normal in 69% (p < 0.0001) and 92% (p < 0.0001) of measurements in which FEF25-75 was abnormal. These results suggest that FEF25-75 may be considered a good indicator of airflow obstruction and a sensitive marker of respiratory improvement in asthmatic children during reduced antigen exposure.
对14名对屋尘螨过敏的轻中度哮喘儿童在高海拔地区（1756米）时，用力肺活量25%至75%之间的用力呼气流量（FEF25 - 75）检测气道阻塞的敏感性进行了研究。在12周内每2周测量一次用力肺活量（FVC）、第1秒用力呼气量（FEV1）、FEF25 - 75和呼气峰值流量（PEF）（共84次测量）。每次测试前确定胸部听诊时是否有哮鸣音。在研究期间，观察到平均（标准差）FEF25 - 75 [预测值的61（12）%对68（11）%，p = 0.005]和PEF [95（16）%对103（13）%，p = 0.002]均有显著改善。FEV1仅有轻微变化[82（7）%对86（6）%，p = 0.05]。84次测量中有12次出现哮鸣音。大多数情况下，哮鸣音与FEF25 - 75值异常相关，但与FEV1或PEF异常无关。在无哮鸣音的日子里，51%的时间FEF25 - 75降低。在FEF25 - 75异常的测量中，FEV1和PEF分别在69%（p < 0.0001）和92%（p < 0.0001）的测量中正常。这些结果表明，在减少抗原暴露期间，FEF25 - 75可被视为气流阻塞的良好指标和哮喘儿童呼吸改善的敏感标志物。
