A comparison between different methods for detecting bronchial hyperreactivity. Bronchial hyperreactivity: methods of study.

The authors evaluated bronchial hyperreactivity comparing two different methods for aspecific bronchostimulation (H2O ultrasonic mist and free running) and a bronchodilation test. The investigation had been carried out on three groups of subjects. The first included 15 nonsmoking normal subjects, the second 23 asthmatic patients and the third 16 rhinitic patients. All subjects were submitted to bronchodynamic tests in three different ways. The ventilatory parameters were FVC, FEV1, MMEF and Vmax25. In normal subjects no significant changes were found. In asthmatic patients the bronchodilation test was positive in 65% of the cases, regarding FEV1 and in 87% regarding the forced flows. The running test was positive in 26% of the cases (FEV1) and in 61% of the cases (forced flows). The ultrasonic mist caused a significant drop in FEV1 in 17% of the cases, while flows were significantly reduced in 30% of the cases. In rhinitic patients the bronchodilation test was positive in 25% of the cases both considering FEV1 and forced expiratory flows. Ultrasonic mist never induced a decrease of FEV1, while flows decreased in 12.5% of the cases. The free running test was positive in 12% of the cases regarding FEV1 and in 25% regarding forced flows.