Spasmodic croup in the adult

Area of Science:

• Respirology
• Otolaryngology
• Pulmonary Medicine

Background:

• Recurrent inspiratory stridor without an apparent organic cause poses a significant clinical challenge.
• Understanding the pathophysiology of such stridor is crucial for effective management.

Observation:

• Fiberoptic bronchoscopy visualized glottic aperture changes during the respiratory cycle in a patient with recurrent inspiratory stridor.
• Observations were made when the patient was asymptomatic, during spontaneous stridor attacks, and after histamine aerosol induction.

Findings:

• Stridor was associated with marked inspiratory glottic constriction and reversed vocal cord movement.
• Intermittent positive pressure ventilation (IPPV) and continuous positive airway pressure (CPAP) alleviated glottic narrowing.
• Inspiratory pulmonary resistance was elevated during stridor and normalized with IPPV/CPAP.

Implications:

• Stridor in this case resulted from dynamic inspiratory vocal cord constriction, potentially triggered by factors like histamine.
• Non-invasive positive airway pressure therapies can reverse stridor by preventing dynamic airway collapse.
• Accurate diagnosis of dynamic vocal cord dysfunction is essential to avoid unnecessary or harmful interventions.