A randomized, placebo-controlled study to evaluate the role of salmeterol in the in-hospital management of asthma

Study objectives: To assess the safety and efficacy of salmeterol xinafoate as an adjunct to conventional therapy for the in-hospital management of acute asthma. Design: A prospective, double-blind, randomized placebo-controlled trial. Setting: Medical wards of a large university-based hospital. Patients: Forty-three patients admitted for an acute exacerbation of asthma. Interventions: Salmeterol (42 μg) or two puffs of placebo every 12 h in addition to standard therapy (short-acting β-agonists, corticosteroids, and anticholinergic agents). Results: No clinically adverse effects were seen with the addition of salmeterol to conventional therapy. After salmeterol, there was no difference in pulse, respiratory rate, oxygen saturation by pulse oximetry, severity of symptoms, or dyspnea score. Patients receiving salmeterol had greater FEV₁ percent improvements than the placebo group at 12, 24, 36, and 48 h. These findings were not statistically significant. By paired Student's t tests, there were significant improvements in FEV₁ (p = 0.03) and FVC (p = 0.03) in the salmeterol group after 48 h of treatment with no comparable improvement in the placebo group. In a subgroup analysis of patients with an initial FEV₁ ≤ 1.5 L, the absolute FEV₁ percent improvement for salmeterol vs placebo was 51% vs 16% at 24 h and 54% vs 40% at 48 h. The relative FEV₁ percent improvement for salmeterol vs placebo was 17% vs 8% at 24 h and 18% vs 14% at 48 h. Conclusion: The addition of salmeterol to conventional therapy is safe and may benefit hospitalized patients with asthma. Further studies are needed to clarify its role in the treatment of acute exacerbation of asthma.