Vocal cord dysfunction in patients hospitalized with symptoms of acute asthma exacerbation

Vocal cord dysfunction (VCD), also called inducible laryngeal obstruction, is characterized by inspiratory closure of the vocal cords associated with paradoxical vocal cord movement. During expiration, closure of the vocal cords is a normal phenomenon precluding a reliable diagnosis of VCD. Diagnosis is made by laryngoscopy upon detection of paradoxical vocal cord movement and a diamond-shaped “chink” during inspiration. VCD was initially considered exclusively as a mimic of asthma, but subsequent studies suggested that it frequently coexists with asthma. Newman and coworkers detected VCD in more than 50%of subjects with severe asthma, and in a previous study we detected VCD in approximately 35% of patients with severe symptomatic asthma and almost 20% of patients with milder disease.