Vocal Cord Dysfunction Mimics Asthma and May Respond to Heliox

Abstract

Vocal cord dysfunction (VCD), an under appreciated cause of wheezing, may be mistaken for or coexist with asthma. The vocal cords involuntarily adduct during inspiration, leading to inspiratory or biphasic wheezing. Asthma therapy offers no benefit and may result in injury. Proof of diagnosis requires endoscopy during an episode. Definitive therapy involves voice training by a speech pathologist, but heliox (20% to 40% oxygen in helium) has been used to reduce symptoms, resulting in dramatic improvement in wheezing and less anxiety. A retrospective review of recent experience with heliox treatment for patients with VCD was conducted, using a search of computerized inpatient and outpatient physician dictation reporting at Scott & White Memorial Hospital and Clinic. Five patients age 10 to 15 years were treated with a favorable response in four. There were no complications of therapy. A high index of suspicion can lead to the diagnosis of VCD, avoiding expensive, inappropriate, and harmful therapy. A trial of heliox inhalation for patients with symptomatic VCD may prove beneficial, analogous to the "reliever" role of β agonists for asthma. Home or school use of heliox may reduce acute care visits, while voice training ("controller" therapy) is instituted.