Inhaled dopamine induces bronchodilatation in patients with bronchial asthma.
OBJECTIVE
To determine the probable bronchodilating effect of dopamine administered by inhalation route in patients with crisis of bronchial asthma and the effect of dopamine on bronchial motor tone.


METHODS
We have studied eighteen (18) patients with crisis of bronchial asthma, ten (10) subjects with bronchial hyperreactivity and ten (10) healthy subjects. Patients with other pulmonary or cardiac disease were excluded. All received by inhalation placebo (0.9% saline solution), dopamine at 0.5 microg/kg/min (controlled by heart rate and arterial pressure with a dynamap), and placebo. Respiratory parameters: forced vital capacity (FVC), forced expiratory volume at the first second (FEV1), forced maximal expiratory flow (FEFmax) and forced expiratory flow at the 50% of vital capacity (FEF50) were measured in each protocol period. Student's paired t test, Wilcoxon and Mann Whitney analysis were performed.


RESULTS
After dopamine inhalation, there was an increase of FVC by 23% (p<0.001); an increase of FEV1 by 39% (p<0.0001); an increase of FEF50 by 33% (p<0.001) and an increase of FEFmax by 31% (p<0.001). There were no respiratory parameter changes in both, subjects with bronchial hyperreactivity and normal after dopamine inhalation.


CONCLUSIONS
Inhaled dopamine induces bronchodilatation in patients with crisis of bronchial asthma. Inhaled dopamine neither alters basal bronchial tone in healthy subjects nor in subjects with bronchial hyperreactivity.
Cabezas
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Department of Physiology, José M. Vargas Medical School, Central, University of Venezuela, Caracas.
Lezama
Y
Y
Vidal
A
A
Velasco
M
M
D000280:Administration, Inhalation; D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000188:drug therapy / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D004298:Dopamine / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009330:Nebulizers and Vaporizers
D001993:Bronchodilator Agents; D004298:Dopamine