A comparison of responses to bronchodilator drugs in chronic bronchitis and chronic asthma

Abstract

Isoprenaline by inhalation, adrenaline by inhalation, subcutaneous adrenaline, intravenous aminophylline, and subcutaneous atropine were administered to two groups of 18 patients suffering from either chronic bronchitis or chronic asthma using a Latin square design. Prednisolone was then given to both groups of patients for six days. The responses to the drugs were assessed by recording the F.E.V._1·0 before and 20 minutes after the administration of the short-acting drugs and daily during the period of prednisolone therapy. No significant differences were found between the responses to the short-acting antispasmodic drugs in the group of patients suffering from chronic bronchitis and only an insignificant improvement in the mean F.E.V._1·0 occurred during the period of prednisolone administration. Significant differences between mean responses to the anti-spasmodic drugs of the group of patients suffering from chronic asthma were observed. The mean F.E.V._1·0 response following subcutaneous adrenaline was 44%, which was significantly better than the 23·7% improvement after adrenaline inhalation (p=0·005) and the mean improvement in F.E.V._1·0 of 17·1% after subcutaneous atropine sulphate (p=0·001). A dramatic improvement in the mean F.E.V._1·0 of 49·5% occurred after six days of prednisolone administration. It is tentatively suggested that a good response to subcutaneous adrenaline and a poor response to subcutaneous atropine, as judged by improvement in the F.E.V._1·0, may be an indication that a good response to prednisolone can be expected in wheezy patients.