Pediatric Airway and Laryngology
The anatomic ladder
Pediatric airway questions test whether you can localize obstruction by history and physical before endoscopy. Congenital stridor is laryngomalacia until proven otherwise (inspiratory, worse supine, improves with prone and time). Biphasic stridor suggests fixed or subglottic lesions; expiratory stridor suggests tracheobronchial disease. Hoarseness in a neonate raises recurrent laryngeal nerve injury, vocal fold paralysis, or laryngeal web. Understand subglottic stenosis grading (Myer-Cotton: grade I <50%, II 51–70%, III 71–99%, IV no lumen) and that grade and symptom severity, not grade alone, drive surgery.
Concepts to master
Recurrent respiratory papillomatosis (HPV 6/11, juvenile onset, aggressive course, adjuvant bevacizumab or cidofovir for frequent recurrence); subglottic hemangioma (biphasic stridor, cutaneous hemangioma clue, propranolol first-line); laryngeal clefts (aspiration, recurrent pneumonia, classify by extent); tracheomalacia and vascular compression; foreign body aspiration (sudden choking, unilateral wheeze, radiolucent). Know tracheostomy indications and pediatric-specific complications (granulation, suprastomal collapse, accidental decannulation).
Traps
Do not assume croup when stridor is atypical or recurrent - question the diagnosis. Beware attributing persistent hoarseness to benign causes without visualizing the larynx. Flexible endoscopy in a child with severe distress can precipitate obstruction; the operating room with anesthesia backup is sometimes the right venue. Also: a normal lateral neck radiograph does not exclude foreign body.
Rule of thumb
Match stridor phase to lesion level: inspiratory = larynx/supraglottic; expiratory = tracheobronchial; biphasic = fixed glottic/subglottic. Then choose the least invasive confirmatory test.
Worked example
A 4-month-old with worsening biphasic stridor and a small facial hemangioma: subglottic hemangioma. Propranolol is first-line; endoscopy confirms; reserve laser/surgery for refractory cases.