Unexpected Subglottic Stenosis Detected During Difficult Intubation for the Induction of General Anesthesia: A Case Report

Subglottic stenosis presents with a wide spectrum of symptoms depending on the severity of the stenosis, which may remain completely asymptomatic and therefore escape routine preoperative evaluation. We report a seven-month-old girl who experienced unanticipated failed tracheal intubation despite an optimal Cormack-Lehane grade I laryngoscopic view. Multiple cuffless endotracheal tubes of progressively smaller sizes encountered identical resistance immediately below the vocal cords, while oxygenation and ventilation remained adequate. Recognizing the possibility of a fixed subglottic lesion, further intubation attempts were avoided. Airway management was safely achieved using a supraglottic airway device, allowing the procedure to proceed without hypoxemia or airway trauma. Postoperative bronchoscopic examination revealed whitish membranous stenosis in the subglottic area. This case underscores that optimal glottic visualization does not guarantee successful intubation in infants and highlights the importance of early recognition of fixed subglottic resistance, timely transition to supraglottic airway devices to prevent airway injury, and prompt bronchoscopic evaluation in unexpected pediatric difficult airways.