An Efficacy Study of BCS Clearing the Oral Colonized Bacterium in Hospitalized Patients With COPD

This a randomized, double-blind, parallel, single-center, exploratory trial. 60 patients will be randomized to two treatments: benzalkonium chloride solution treatment or normal saline treatment.The purpose of study is to evaluate the efficacy and safety of benzalkonium chloride solution clearing the oral colonized bacterium in hospitalized patients with COPD.