Capacity of using DPIs during COPD exacerbations

Abstract

Background: During COPD exacerbations(ECOPD) treatment with long acting bronchodilators(LABs) is replaced by short acting agents via nebulizers or spacers due to the belief that patients cannot use dry powder inhalers(DPIs) The aim of the study was to test whether patients hospitalized for ECOPD are able use DPIs.

Methods: Inspiratory flow (IF) was measured daily with a portable handheld inspiratory flow meter (In-Check Oral inhaler assessment kit), containing a series of adapters that simulate the resistance of 4 DPIs [Handinhaler(HH), Breezhaler/Aerolizer(B/F), Discus(A/A/D) and Turbohaler(T)]. Dyspnea, spirometry, ABGs and the ability to achieve the minimum and the optimal required IF for each DPI were recorded daily. All measurements were examined as possible predictors of achievement the minimum and optimal IF for each DPI.

Results: 16 patients (14 male, mean age 73.5±7.4) were included. On admission, minimum IF was achieved in 87.5%, 68.8%, 87.5% and 68.6% and optimal IF in 12.5%, 0%, 87.5% and 68.8% of patients for T, B/F, A/A/D and HH respectively. On discharge minimum IF was achieved in 100%, 81.3% 93.8%, and 93.8% while optimal IF in 31.3%, 6.3%, 93.8%, and 93.8% of patients for T, B/F, A/A/D and HH respectively. No parameter predicted achievement of minimum IF. Dyspnea [AUC 0.877 95%CI(0.810, 0.927) and 0.729(0.645, 0.802)] and FEV₁[0.870(0.801, 0.922) and 0.805(0.728, 0.868)] were predictors of achievement of optimal IF for B/F and T respectively. PO₂/FiO₂ ratio was a predictor of achievement of optimal IF for B/F [0.921(0.862, 0.961)]

Conclusions: Most patients are able to use DPIs during ECOPD. The possible effects of the continuation of LABs during ECOPD in patients able to receive them should be evaluated in the future.