[Response to bronchodilators among patients with bronchial asthma]

The response to bronchodilators was evaluated in 295 spirometric studies performed in 82 patients with asthma (defined according to ATS criteria, with at least one previous basal test with 20% of change in FEV1 compared with the present test). The response to bronchodilators (Bd) was measured fifteen minutes after the inhalation of salbutamol 200 mcg by metered dose inhaler and in the absence of Bd inhalation in the previous six hours. Sixty-eight spirometries (23%) were classified as with no response to Bd (NR) (absolute delta FEVI[delta abs] < 200 ml, delta FEV1 in percentage of initial FEVI[delta%] < 15%, delta FVC in percentage of the initial [delta FVC] < 15% and delta FEF 25-75% in percentage of the initial [delta FEF] < 25%). Only 23% (n = 16) of them showed an initial FEVI greater than 80% of predicted. In this group 4 tests (5% of NR, 1.3% of the whole) showed delta abs > 150 ml and 1 (1.5% of NR, 0.3% of whole) delta% > 12%. Thirty six percent of the whole population (n = 109) would have been classified as NR taking as unique criterion delta VEF1% < 15%, 24 of which (8% of whole population) showed delta VEF1 abs > 200 ml (initial FEVI 2.48 +/- 0.60 l) (Table 3). On the other hand, 94 spirometries (31% of the whole) would have been classified as NR taking as unique criterion delta abs < 200 ml. twelve of which (4% of the whole) showed delta% > 15% (initial FEVI 0.81 +/- 0.171) (Table 2).(ABSTRACT TRUNCATED AT 250 WORDS)