Reactivity of the bronchi as a function of their initial state in children with asthma

: The aim of the study was to assess the effect of peripheral bronchial base-line status on the result of the bronchial provocation test. The study was carried out on a group of 65 children with bronchial asthma. Bronchial reactivity was assessed utilizing the carbachol provocation test. Higher reactivity was seen in children with initially lower indices of peripheral bronchial flow (MEF50, MEF25) (PC20 = 3,789 +/- 0.014 mg/ml) in comparison with children with normal indices (PC20 = 74,608 +/- 0,038 mg/ml) (p < 0.001). A linear correlation was found between the results of bronchial provocation (PC) and initial standardized small airway flow values (MEF50 - r = 0.56, p < 0.001; MEF25 - r = 0.49, p < 0.001). The correlation between bronchial provocation and initial FEV1/VC was weaker (r = 0.39 p < 0.01). The authors conclude that demonstration of decreased flow in peripheral, small airways utilizing MEF values enable to predict a positive result of bronchial provocation tests.