What is a common cause of acquired subglottic stenosis?

• A. Prolonged Intubation
• B. Congenital Defect
• C. Allergic Reaction
• D. Viral Infection

Answer: (A)

Prolonged intubation is the most common cause of acquired subglottic stenosis because extended pressure from the endotracheal tube injures the subglottic mucosa. This injury leads to inflammation, granulation tissue, and then fibrotic scar formation that narrows the airway at the subglottic level. This process occurs after airway instrumentation or trauma, which defines it as acquired rather than congenital.

Congenital defects cause stenosis present at birth due to developmental abnormalities, not from an injury sustained after the airway has formed. Allergic reactions and viral infections can cause swelling, but they typically produce reversible edema rather than a persistent, scarred narrowing of the subglottic space, so they don’t account for the fixed obstruction seen in acquired stenosis.