[Study of bronchial reactivity by means of cold air inhalation].

In 24 children with bronchial asthma and 16 children of a control group provocation by three-minute inhalation of cold air was applied under eucapnic condition on a RHES apparatus (E. Jaeger, GFR). After hyperventilation changes in the resistance of the airways were investigated by the occlusion method and repeatedly parameters of ventilation were examined by the flow-volume loop method. In the group of asthmatic children a significantly increased resistance was recorded after provocation with an onset already during the first minute after completed hyperventilation, and it persisted to the 9th minute. In the investigated parameters of the flow-volume loop (FEV 1, MEF 25/75) the maximum drop was recorded between the 3rd and 5th minute after provocation. In the control group no significant changes developed after provocation. Provocation by eucapnic hyperventilation of cold air is in particular in paediatric pneumological and allergological diagnosis a perspective method which does not cause discomfort to the patient and is well tolerated.