Levodopa reverse stridor and prevent subsequent endotracheal intubation in Parkinson disease patients with bilateral vocal cord palsy

BACKGROUND Respiratory abnormalities are often overlooked; however, because of their potential comorbidity, they must be analyzed to determine the most effective treatment for patients with Parkinson disease (PD). Among various theories on respiratory abnormalities in PD, "upper airway obstruction" and "restrictive respiratory disorders" are 2 of the most accepted etiologies; both appear to be related to basal ganglia dysfunction. Complex vocal cord muscle dysfunction contributes to stridor, which can be a manifestation of nigrostriatal dopaminergic dysfunction. Stridor is a lethal form of upper airway obstruction in PD patients; its most frequent causes are bilateral vocal cord palsy, laryngeal spasms, and dystonia of the supra-laryngeal muscle. Several previous studies have suggested that levodopa administration induces a significant improvement of both lung function and symptoms of parkinsonian syndrome. CASE SUMMARY We reported a 77-year-old gentleman PD patient admitted for acute levodopa-responsive stridor resulting from bilateral vocal cord palsy. Dopaminergic therapy prevented the need for subsequent endotracheal intubation and tracheostomy treatment. CONCLUSION It is vital to understand that complex vocal cord muscle dysfunction may be related to nigrostriatal dopaminergic dysfunction in PD patients. The strategy of levodopa up-titration should be considered an option because it may be beneficial in relieving both stridor and parkinsonian syndrome, and in preventing respiratory failure.