[Study of bronchial reactivity using dry, cold air and eucapnic hyperventilation]

The paper is concerned with diagnostic value provocation test with cold dry air and eucapnic hyperventilation for testing bronchial reactivity. Forty healthy subjects, 90 patients with bronchial asthma, 20 with chronic bronchitis, 2 with sarcoidosis, 14 with pollenosis, one with mucoviscidosis and 22 with dispnoa or long-lasting dry cough were tested. The total of 149 provocations have been carried out in patients and 40 in healthy subjects. Airways resistance after provocation with cold dry air and eucapnic hyperventilation in patients with bronchial asthma is increased over 100% in 13 (14%), over 200% in 12 (13%), over 300% in 25 (26%) and over 500% in 40 (47%) patients. Less intensive asthmatic attack was provoked in 14 (15%), moderate attack in 18 (20%) and severe attack in 58 (65%) patients with asthma. Provocation time lasted from 2 to 9.9 min. Inspired air temperature ranged from -23 degrees C to -26 degrees C. Airway resistance was measured before and after provocation by means of Bronchoscreen. Central airway resistance was increased in 2 patients, peripheral resistance in 78, and both resistances in 10 patients with bronchial asthma. The results pointed out that provocation with cold dry air and eucapnic hyperventilation resulted in bronchial hyperreactivity exclusively in patients with bronchial asthma, and the test was positive in 100% of patients with bronchial asthma.