Abstract
This study evaluates the effect of three different bronchodilators (beta 2-adrenergic, anticholinergic and methylxanthine) alone and in randomized sequence, during an exacerbation in thirteen patients with chronic obstructive pulmonary disease. Dose-response curves were obtained for inhaled salbutamol and inhaled ipratropium bromide. The bronchodilator effect of a perfusion of aminophylline was also assessed. When a plateau of bronchodilatation was achieved with one agent, one dose of a second bronchodilator was administered to see whether additional bronchodilation could be achieved. The increments in FEV1 and FVC were similar with the three agents. The addition of a second bronchodilator did not result in significant increments in most of the patients. In at least half of the patients the doses of salbutamol and ipratropium that produced the maximal bronchodilatation were twice that currently employed.
