Bronchial challenge, assessed with forced expiratory manoeuvres and airway impedance

Conclusion: Measuring PC40_Rrs6 shortens the challenge test and lowers the concentrations of bronchoconstrictor agents as compared to measurements of PC20_FEV1. The FOT-method was less strenuous for patients. In spite of the fact that the reproducibility is two-fold worse than measuring PC20_FEV1,it still remains quite acceptable at a mean of 0.3 doubling dose. The respiratory muscle strength was deteriorated after the challenge test.