Effectiveness of salmeterol in stable COPD.

Thirty patients of stable chronic obstructive pulmonary disease (COPD) were studied for evaluation of effectiveness of inhaled salmeterol in a double blind, randomised, placebo controlled trial for seven days. Baseline spirometery and breathlessness score after 6 minutes walk test were assessed in all patients. Bronchial asthma was excluded in each patient by reversibility test with 200 ug of salbutamol inhalation. After inhalation of two puffs from a given inhaler through spacer device in the morning, spirometery was carried out 1, 3, 6 and 12 hrs after inhalation on day 1, 3 and 7 of trial. Six minutes walk test and breathlessness score were assessed after 3 hrs of inhalation on days 1, 3 and 7. The maximum bronchodilator response to salmeterol was observed on 7th day at three hours after inhalation. The mean increase in FEV1 was 29.2% of baseline value, which was significant as compared to placebo where the mean increase in FEV1 was 3.3% of the baseline value. The peak rise in FEV1 was observed at three hours after inhalation on all the three days. The bronchodilator effect of salmeterol persisted for upto 12 hours. The mean maximum increase in walking distance in 6 minutes walk test was observed on 7th day in salmeterol group, which was 50.7 metres whereas in placebo group it was 12.2 meters. The patients in salmeterol group perceived less breathlessness after the six minutes walk test. The study concluded that salmeterol 50 micrograms twice a day is effective in improving lung functions in patients with stable COPD and can be recommended as maintenance therapy for stable COPD patients.