Study objectives: Despite the widespread use of short-acting, inhaled β2-agonists in acute exacerbations of COPD (AECOPDs), little is known about their optimal dose. The aims of this study are to compare the bronchodilator response to incremental doses of inhaled albuterol during and after recovery from an AECOPD, and to compare the effects of regular nebulized albuterol, 2.5 mg and 5 mg, on the speed of recovery.
Methods: Eighty-six patients admitted with an AECOPD were recruited. Each patient was administered incremental doses of inhaled albuterol on hospital admission and following recovery. Dose-response curves were constructed based on FEV1 and peak expiratory flow rate (PEFR) recorded after each incremental dose. Patients were then randomized in a double-blind fashion to receive 2.5 mg or 5 mg of nebulized albuterol q4h until recovery. Twice-daily PEFR, the number of extra doses of bronchodilators, and side effects reported were recorded.
Results: Maximal bronchodilation (Emax) FEV1 (maximal bronchodilatory response to albuterol) increased from 0.64 ± 0.27 L/min during the exacerbation to 0.94 ± 0.38 L/min during recovery (p < 0.001). The Emax PEFR increased from 147.53 ± 62.46 L/min to 222.94 ± 73.82 L/min after recovery (p = <0.001). There was no significant difference in rate of recovery of PEFR (p = 0.684), duration of hospital stay (p = 0.084), or side effects (p = 0.506) between the groups receiving 2.5 mg or 5 mg of nebulized albuterol.
Conclusions: There was significant improvement in Emax to inhaled albuterol as the COPD exacerbation resolved. There was no significant difference in outcomes including length of hospital stay or recovery of lung function between patients treated with regular 2.5 mg vs 5 mg of nebulized albuterol during an AECOPD.